8 A distributed power harvesting system comprising:

9 a plurality of DC power sources (301,401,301,601,701);

10 a plurality of converters (305,405,505,605,705), and

11 wherein each of the converters (305,405,505,605,705) comprises:

12 i input terminals (614,616,716) coupled to a respective DC power source (301,401,301,601,701);

13 ii output terminals (610,612,712) coupled in series to the other converters (305,405,505,605,705), thereby forming a serial string; and

14 iii a power conversion portion (604) for converting the power received at the input terminals (614,616) to an output power at the output terminals (610,612,712); and

15 a power delivery device (304,404,504) coupled to the serial string,

19 A method for harvesting power from a distributed power system having a plurality of DC power sources (301,401,301,601,701) and a plurality of DC power converters (305,405,505,605,705), the method comprising:

20 coupling each of the power sources (301,401,301,601,701) to a respective DC power converter (305,405,505,605,705);

21 coupling the power converters (305,405,505,605,705) in series, to thereby form at least one serial string;

22 coupling the serial string to a power delivery device (304,404,504);

23 fixing the input voltage to the power delivery device (304,404,504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301,401,301,601,701); and controlling power output from each power source (301,401,301,601,701) individually and individually varying the input voltage and current to each respective converter (305,405,505,605,705) according to a predetermined criteria,

24 wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614,616,716) of the buck plus boost converters (305,405,505,605,705) according to predetermined criteria,

25 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together.

27 Verteiltes Leistungswandler-System umfassend:

28 eine Vielzahl von Gleichstrom-Leistungsquellen

29 (301, 401, 501, 601, 701);

30 eine Vielzahl von Wandlern (305, 405, 505, 605, 705), worin

31 jeder der Wandler (305, 405, 505, 605, 705) umfasst:

32 i Eingangsanschlüsse (614, 616, 716), die an eine jeweiligen [sic!] Gleichstrom-Leistungsquelle gekoppelt sind;

33 ii Ausgangsanschlüsse (610, 612, 712), die in Reihe mit den Wandlern ((305, 405, 505, 605,705) gekoppelt sind, und dadurch eine Reiheneinschaltungskette bilden; und

34 iii einen Leistungswandlerabschnitt (604) zum Wandeln der an den Eingangsanschlüssen (614,616) empfangenen Leistung in eine Ausgangsleistung an den Ausgangsanschlüssen (610,612,712) umzusetzen; und

35 eine Leistungsabgabeeinrichtung (304, 404, 504), die mit der Reiheneinschaltungskette gekoppelt ist,

39 Verfahren zur Leistungsumwandlung bei einem verteilten Leistungswandlersystem mit einer Vielzahl von Gleichstrom-Leistungsquellen (301, 401, 501,601, 701) und einer Vielzahl von Gleichstrom-Leistungswandlern (305, 405, 505, 605, 705), wobei das Verfahren umfasst:

40 Ankoppeln von jeder der Leistungsquellen (301, 401, 501, 601, 701) an einen jeweiligen Gleichstrom-Leistungswandler (305, 405, 505, 605, 705);

41 Koppen [sic!] der Leistungswandler (305, 405, 505, 605, 705) in Reihe, um dadurch wenigstens eine Reihenschaltungskette zu bilden;

42 Koppeln der Reihenschaltungskette mit einer Leistungsabgabe-einrichtung (304, 404, 504);

43 Fixieren der Eingangsspannung an die Leistungsabgabeeinrich-tung (304,404,504) an einem vorgegebenen Wert, um dadurch zu erzwingen, dass der Strom, der durch die Reihenschaltungskette fließt, entsprechend der Leistung, die durch die Leistungsquellen (301, 401, 501, 601, 701) geliefert wird, variiert; und

44 individuelles Steuern des Leistungsausgangs von jeder Leistungsquelle (301, 401, 501, 601, 701) und individuelles Variieren der Eingangsspannung und des Stroms an jedem entsprechenden Wandler (305, 405, 505, 605, 705) entsprechend vorgegebenen Kriterien,

45 worin Abwärts- plus Aufwärts-Wandler verwendet werden, die jeweils einen Abwärtswandler, einen Aufwärts-Wandler, einen Controller (606) und eine Schaltungsschleife (608, 708) aufweisen, die die Spannung und den Strom an den Eingangsanschlüssen (614, 616, 716) der Abwärts- plus Aufwärts-Wandler (305, 405, 505, 605, 705) nach vorgegebenen Kriterien einstellen,

46 worin der Controller (606) in Antwort auf den MPPT-Teil und den Strom oder die Spannung aus den Ausgangsanschlüssen (610, 612) entweder den Abwärtswandler oder den Aufwärts-Wandler selektiv aktiviert oder den Abwärtswandler und den Aufwärts-Wandler zusammen aktiviert.

72 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

73 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

74 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

75 coupling the serial string to a power delivery device (304, 404, 504);

76 fixing, by the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 501, 601, 701); and

77 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

78 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together.

80 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

81 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

82 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

83 coupling the serial string to a power delivery device (304, 404, 504);

84 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 501, 601, 701); and

85 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

86 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together.

88 A distributed power harvesting system comprising:

89 a plurality of DC power sources (301, 401, 301, 601, 701);

90 a plurality of converters (305, 405, 505, 605, 705), and

91 wherein each of the converters (305, 405, 505, 605, 705) comprises:

92 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

93 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

94 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

95 a power delivery device (304, 404, 504) coupled to the serial string,

99 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

100 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305,405,505,605,705);

101 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

102 coupling the serial string to a power delivery device (304, 404, 504);

103 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

104 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

105 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string.

107 A distributed power harvesting system comprising:

108 a plurality of DC power sources (301, 401, 301, 601, 701);

109 a plurality of converters (305, 405, 505, 605, 705), and

110 wherein each of the converters (305, 405, 505, 605, 705) comprises:

111 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

112 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

113 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

114 a power delivery device (304, 404, 504) coupled to the serial string,

120 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

121 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

122 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

123 coupling the serial string to a power delivery device (304, 404, 504);

124 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

125 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

126 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together, and

129 A distributed power harvesting system comprising:

130 a plurality of DC power sources (301, 401, 301, 601, 701);

131 a plurality of converters (305, 405, 505, 605, 705), and

132 wherein each of the converters (305, 405, 505, 605, 705) comprises:

133 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

134 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

135 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

136 a power delivery device (304, 404, 504) coupled to the serial string,

142 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

143 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

144 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

145 coupling the serial string to a power delivery device (304, 404, 504);

146 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

147 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

148 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together, and

151 A distributed power harvesting system comprising:

152 a plurality of DC power sources (301, 401, 301, 601, 701);

153 a plurality of converters (305, 405, 505, 605, 705), and

154 wherein each of the converters (305, 405, 505, 605, 705) comprises:

155 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

156 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

157 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

158 a power delivery device (304, 404, 504) coupled to the serial string,

162 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

163 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

164 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

165 coupling the serial string to a power delivery device (304, 404, 504);

166 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

167 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

168 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together.

170 A distributed power harvesting system comprising:

171 a plurality of DC power sources (301, 401, 301, 601, 701);

172 a plurality of converters (305, 405, 505, 605, 705), and

173 wherein each of the converters (305, 405, 505, 605, 705) comprises:

174 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

175 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

176 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

177 a power delivery device (304, 404, 504) coupled to the serial string,

181 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

182 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

183 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

184 coupling the serial string to a power delivery device (304, 404, 504);

185 fixing by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

186 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

187 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string.

189 A distributed power harvesting system comprising:

190 a plurality of DC power sources (301, 401, 301, 601, 701);

191 a plurality of converters (305, 405, 505, 605, 705), and

192 wherein each of the converters (305, 405, 505, 605, 705) comprises:

193 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

194 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

195 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

196 a power delivery device (304, 404, 504) coupled to the serial string,

200 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

201 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

202 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

203 coupling the serial string to a power delivery device (304, 404, 504);

204 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

205 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

206 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together.

208 A distributed power harvesting system comprising:

209 a plurality of DC power sources (301, 401, 301, 601, 701);

210 a plurality of converters (305, 405, 505, 605, 705),

211 and

212 wherein each of the converters (305, 405, 505, 605, 705) comprises:

213 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

214 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

215 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

216 a power delivery device (304, 404, 504) coupled to the serial string,

220 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

221 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

222 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

223 coupling the serial string to a power delivery device (304, 404, 504);

224 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

225 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

226 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string.

228 A distributed power harvesting system comprising:

229 a plurality of DC power sources (301, 401, 301, 601, 701);

230 a plurality of converters (305, 405, 505, 605, 705),

231 and

232 wherein each of the converters (305, 405, 505, 605, 705) comprises:

233 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

234 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

235 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

236 a power delivery device (304, 404, 504) coupled to the serial string,

240 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

241 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

242 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

243 coupling the serial string to a power delivery device (304, 404, 504);

244 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

245 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

246 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string.

248 A distributed power harvesting system comprising:

249 a plurality of DC power sources (301, 401, 301, 601, 701);

250 a plurality of converters (305, 405, 505, 605, 705), and

251 wherein each of the converters (305, 405, 505, 605, 705) comprises:

252 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

253 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

254 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

255 a power delivery device (304, 404, 504) coupled to the serial string,

261 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

262 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

263 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

264 coupling the serial string to a power delivery device (304, 404, 504);

265 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

266 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

267 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together, and

270 A distributed power harvesting system comprising:

271 a plurality of DC power sources (301, 401, 301, 601, 701);

272 a plurality of converters (305, 405, 505, 605, 705), and

273 wherein each of the converters (305, 405, 505, 605, 705) comprises:

274 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

275 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

276 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

277 a power delivery device (304, 404, 504) coupled to the serial string,

283 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

284 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

285 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

286 coupling the serial string to a power delivery device (304, 404, 504);

287 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

288 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

289 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

292 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

293 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

294 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

295 coupling the serial string to a power delivery device (304, 404, 504);

296 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

297 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

298 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

301 A distributed power harvesting system comprising:

302 a plurality of DC power sources (301, 401, 301, 601, 701);

303 a plurality of converters (305, 405, 505, 605, 705), and

304 wherein each of the converters (305, 405, 505, 605, 705) comprises:

305 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

306 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

307 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

308 a power delivery device (304, 404, 504) coupled to the serial string,

314 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

315 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

316 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

317 coupling the serial string to a power delivery device (304, 404, 504);

318 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

319 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

320 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together, and

323 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

324 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

325 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

326 coupling the serial string to a power delivery device (304, 404, 504);

327 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

328 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

329 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together, and

332 A distributed power harvesting system comprising:

333 a plurality of DC power sources (301, 401, 301,601, 701);

334 a plurality of converters (305, 405, 505, 605, 705), and

335 wherein each of the converters (305, 405, 505, 605, 705) comprises:

336 i input terminals (614,616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

337 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

338 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

339 a power delivery device (304, 404, 504) coupled to the serial string,

345 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

346 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

347 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

348 coupling the serial string to a power delivery device (304, 404, 504);

349 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

350 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605,705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

351 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

354 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

355 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

356 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

357 coupling the serial string to a power delivery device (304, 404, 504);

358 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

359 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

360 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

363 A distributed power harvesting system comprising:

364 a plurality of DC power sources (301, 401, 301, 601, 701);

365 a plurality of converters (305, 405, 505, 605,705), and

366 wherein each of the converters (305, 405, 505, 605, 705) comprises:

367 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

368 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

369 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

370 a power delivery device (304, 404, 504) coupled to the serial string,

376 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

377 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

378 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

379 coupling the serial string to a power delivery device (304, 404, 504);

380 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

381 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

382 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together, and

385 A distributed power harvesting system comprising:

386 a plurality of DC power sources (301,401,301,601,701);

387 a plurality of converters (305,405,505,605,705), and

388 wherein each of the converters (305,405,505,605,705) comprises:

389 i input terminals (614,616,716) coupled to a respective DC power source (301,401,301,601,701);

390 ii output terminals (610,612,712) coupled in series to the other converters (305,405,505,605,705), thereby forming a serial string; and

391 iii a power conversion portion (604) for converting the power received at the input terminals (614,616) to an output power at the output terminals (610,612,712); and

392 a power delivery device (304,404,504) coupled to the serial string,

398 A method for harvesting power from a distributed power system having a plurality of DC power sources (301,401,301,601,701) and a plurality of DC power converters (305,405,505,605,705), the method comprising:

399 coupling each of the power sources (301,401,301,601,701) to a respective DC power converter (305,405,505,605,705);

400 coupling the power converters (305,405,505,605,705) in series, to thereby form at least one serial string;

401 coupling the serial string to a power delivery device (304,404,504);

402 fixing the input voltage to the power delivery device (304,404,504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301,401,301,601,701); and

403 controlling power output from each power source (301,401,301,601,701) individually and individually varying the input voltage and current to each respective converter (305,405,505,605,705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614,616,716) of the buck plus boost converters (305,405,505,605,705) according to predetermined criteria,

404 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

407 A method for harvesting power from a distributed power system having a plurality of DC power sources (301,401,301,601,701) and a plurality of DC power converters (305,405,505,605,705), the method comprising:

408 coupling each of the power sources (301,401,301,601,701) to a respective DC power converter (305,405,505,605,705);

409 coupling the power converters (305,405,505,605,705) in series, to thereby form at least one serial string;

410 coupling the serial string to a power delivery device (304,404,504);

411 fixing, by a control part of the power delivery device (304,404,504), the input voltage to the power delivery device (304,404,504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301,401,301,601,701); and

412 controlling power output from each power source (301,401,301,601,701) individually and individually varying the input voltage and current to each respective converter (305,405,505,605,705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614,616,716) of the buck plus boost converters (305,405,505,605,705) according to predetermined criteria,

413 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

416 A distributed power harvesting system comprising:

417 a plurality of DC power sources (301,401,301,601,701);

418 a plurality of converters (305,405,505,605,705), and

419 wherein each of the converters (305,405,505,605,705) comprises:

420 i input terminals (614,616,716) coupled to a respective DC power source (301,401,301,601,701);

421 ii output terminals (610,612,712) coupled in series to the other converters (305,405,505,605,705), thereby forming a serial string; and

422 iii a power conversion portion (604) for converting the power received at the input terminals (614,616) to an output power at the output terminals (610,612,712); and

423 a power delivery device (304,404,504) coupled to the serial string,

429 A method for harvesting power from a distributed power system having a plurality of DC power sources (301,401,301,601,701) and a plurality of DC power converters (305,405,505,605,705), the method comprising:

430 coupling each of the power sources (301,401,301,601,701) to a respective DC power converter (305,405,505,605,705);

431 coupling the power converters (305,405,505,605,705) in series, to thereby form at least one serial string;

432 coupling the serial string to a power delivery device (304,404,504);

433 fixing the input voltage to the power delivery device (304,404,504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301,401,301,601,701); and

434 controlling power output from each power source (301,401,301,601,701) individually and individually varying the input voltage and current to each respective converter (305,405,505,605,705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614,616,716) of the buck plus boost converters (305,405,505,605,705) according to predetermined criteria,

435 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together, and

438 A method for harvesting power from a distributed power system having a plurality of DC power sources (301,401,301,601,701) and a plurality of DC power converters (305,405,505,605,705), the method comprising:

439 coupling each of the power sources (301,401,301,601,701) to a respective DC power converter (305,405,505,605,705);

440 coupling the power converters (305,405,505,605,705) in series, to thereby form at least one serial string;

441 coupling the serial string to a power delivery device (304,404,504);

442 fixing, by a control part of the power delivery device (304,404,504), the input voltage to the power delivery device (304,404,504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301,401,301,601,701); and

443 controlling power output from each power source (301,401,301,601,701) individually and individually varying the input voltage and current to each respective converter (305,405,505,605,705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608,708) setting the voltage and current at the input terminals (614,616,716) of the buck plus boost converters (305,405,505,605,705) according to predetermined criteria,

444 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together, and

447 A distributed power harvesting system comprising:

448 a plurality of DC power sources (301, 401, 301, 601, 701);

449 a plurality of converters (305, 405, 505, 605, 705), and

450 wherein each of the converters (305, 405, 505, 605, 705) comprises:

451 i input terminals (614, 616, 716) coupled to a respective DC power source (301, 401, 301, 601, 701);

452 ii output terminals (610, 612, 712) coupled in series to the other converters (305, 405, 505, 605, 705), thereby forming a serial string; and

453 iii a power conversion portion (604) for converting the power received at the input terminals (614, 616) to an output power at the output terminals (610, 612, 712); and

454 a power delivery device (304, 404, 504) coupled to the serial string,

460 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

461 coupling each of the power sources (301, 401, 301, 601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

462 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

463 coupling the serial string to a power delivery device (304, 404, 504);

464 fixing the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

465 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

466 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

469 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301, 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

470 coupling each of the power sources (301, 401, 301,601, 701) to a respective DC power converter (305, 405, 505, 605, 705);

471 coupling the power converters (305, 405, 505, 605, 705) in series, to thereby form at least one serial string;

472 coupling the serial string to a power delivery device (304, 404, 504);

473 fixing, by a control part of the power delivery device (304, 404, 504), the input voltage to the power delivery device (304, 404, 504) to a predetermined value, thereby forcing current flowing through the serial string to vary according to power provided by the power sources (301, 401, 301, 601, 701); and

474 controlling power output from each power source (301, 401, 301, 601, 701) individually and individually varying the input voltage and current to each respective converter (305, 405, 505, 605, 705) according to a predetermined criteria, wherein buck plus boost converters are used each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria,

475 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string, and

484 Hintergrund des Streitpatents sind Photovoltaik-Anlagen, auch wenn in den unabhängigen Patentansprüchen allgemein von Gleichstrom-Leistungsquellen die Rede ist.

485 Eine einzelne Photovoltaikzelle hat eine Ausgangsspannung von 0,5 Volt bis 4 Volt. Erst durch die Reihenschaltung vieler solcher Zellen zu Modulen (laut Absatz 0048 der Streitpatentschrift erzeugt jedes Paneel bzw. Modul 32 Volt) und schließlich zu Anlagen kann eine Systemspannung (Abs. 0048: 400 Volt) erreicht werden, die ein Mehrfaches der Modulspannung beträgt.

486 Gemäß Streitpatentschrift ist jeder einzelnen Gleichspannungsquelle ein separater DC/DC Wandler zugeordnet, wobei die Ausgänge der DC/DC-Wandler in Reihe geschaltet werden, so dass sich die resultierende Systemspannung aus der Summe der Ausgangsspannungen der DC/DC-Wandler ergibt. Über einen Wechselrichter wird dann schließlich in ein Wechselspannungsnetz eingespeist (Figur 3 i. V. m. den Absätzen 0036 und 0037).

487 In der Beschreibungseinleitung (Abs. 0003 bis 0011) ist eine ganze Reihe von Schwierigkeiten aufgelistet, die sich beim Betrieb einer PV-Anlage ergeben würden.

488 In der Beschreibungseinleitung ist angegeben, es bestehe Bedarf an Lösungen für eine effektive Topologie zur Verbindung von mehreren Gleichstrom-Leistungsquellen mit der Last, zum Beispiel Stromnetz, Stromspeicheranordnung usw. (Abs. 0016, letzter Satz).

489 Als für die Lösung der Ausgabe zuständigen Fachmann geht der Senat von einem Diplomingenieur bzw. Master der Fachrichtung Elektrotechnik aus, der über mehrjährige Erfahrung in der Entwicklung von Leistungselektronikschaltungen für Photovoltaikanlagen, insbesondere der dafür erforderlichen Stromrichter verfügt.

490 Gelöst werde die Aufgabe durch ein dezentrales Energieerzeugungssystem gemäß erteiltem Patentanspruch 1 (Hauptantrag), der wie folgt gegliedert werden kann (Übersetzung gemäß Streitpatentschrift EP 2 135 348 B1):

491 A distributed power harvesting system

493 comprising:

509 the converters (305, 405, 505, 605, 705) are buck plus boost converters

511 each comprising a buck converter, a boost converter, a controller (606) and a circuit loop (608, 708) setting the voltage and current at the input terminals (614, 616, 716) of the buck plus boost converters (305, 405, 505, 605, 705) according to predetermined criteria;

513 wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together, and

515 that the power delivery device (304, 404, 504) comprises a control part maintaining the input voltage to the power delivery device (304,404,504) at a predetermined value.

518 A method for harvesting power from a distributed power system having a plurality of DC power sources (301, 401, 301 [sic!], 601, 701) and a plurality of DC power converters (305, 405, 505, 605, 705), the method comprising:

530 wherein buck plus boost converters are used

536 wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or activates the buck converter and the boost converter together.

584 Der Senat legt seiner Entscheidung folgende Überlegungen des Fachmanns zu den Angaben in den Patentansprüchen 1 nach Haupt- und Hilfsanträgen zugrunde:

d)

588 Der Bezeichnung "power conversion portion” (Merkmal 1.1.2.3) sowie der angegebenen Wirkung, an den Eingangsanschlüssen empfangene Leistung in eine Ausgangsleistung an den Ausgangsanschlüssen umzusetzen, entnimmt der Fachmann nicht mehr, als er schon bei dem Begriff DC/DC-Wandler mitliest. Die Leistung

sollte nämlich bis auf die unvermeidbaren Verluste konstant sein. Wird die Spannung verändert, ändert sich zwangsläufig auch der Strom, derart, dass die Leistung konstant bleibt.

j)

597 Da gemäß Merkmal 1.5 die Spannung auf dem DC-Bus, also am Eingang des DC/AC-Wandlers, auf einen konstanten Wert geregelt wird und sich zugleich die Leistung, die über den Bus übertragen wird, durch die Summe der von den einzelnen MPPTs eingestellten Leistungen ergibt, fließt in der ausgangsseitigen Reihenschaltung der DC/DC-Wandler ein quasi-eingeprägter Strom.

598 Die Eingangsleistung der DC/DC-Wandler ist, wie ausgeführt, durch die aktuelle Sonneneinstrahlung gegeben und damit auch deren Ausgangsleistung. Somit ergeben sich die jeweiligen Ausgangsspannungen der einzelnen DC/DC-Wandler aus der Beziehung

, wobei wiederum selbstverständlich die Summe der Ausgangsspannungen der in Reihe geschalteten DC/DC-Wandler gleich der Eingangsspannung des DC/AC-Wandlers ist. Damit wechselwirken bei dem beanspruchten System eine Vielzahl von Regelkreisen, nämlich einer je Kombination DC-Quelle mit DC/DC-Wandler und derjenige des DC/AC-Wandlers.

599 II. Zum geltend gemachten Nichtigkeitsgrund der unzulässigen Erweiterung

600 Der Einwand der Klägerin, die Patentansprüche 1 sowie 8 seien gegenüber der ursprünglichen Anmeldung in unzulässiger Weise erweitert, greift nicht. Dies gilt auch soweit sie behauptet, dass im ursprünglichen Patentanspruch 7 beansprucht worden sei, dass die Steuerung unabhängig voneinander (selectively) entweder den Abwärtswandler oder den Aufwärtswandler aktiviert.

601 Dagegen umfasse das Merkmal 1.4 des erteilten Patentanspruchs 1 zusätzlich die Variante, dass Abwärtswandler und Aufwärtswandler zugleich aktiviert seien.

602 Es ist zwar zutreffend, dass auf die von der Klägerin als unzulässige Erweiterung angegriffene Variante ursprünglich kein Patentanspruch gerichtet war, jedoch ist in der Beschreibung der ursprünglichen Anmeldung WO 2008/132553 A2 (Absatz 0078, letzter Satz) angegeben, dass Ab- und Aufwärtswandler in Betrieb sind, wenn die Ausgangsspannung nahezu gleich der Eingangsspannung des Wandlers ist. Noch allgemeiner steht in Absatz 0079: "In some circumstances both the buck and boost portions may operate together.”

603 Da den ursprünglichen Patentansprüchen keine einschränkende Wirkung zukommt, konnte die Patentinhaberin später auf die Beschreibung zurückgreifen und die lediglich dort erwähnte Variante in die Patentansprüche aufnehmen.

604 Das Weglassen der Bedingung, dass die Ausgangsspannung nahezu gleich der Eingangsspannung sein muss, stellt zudem keine unzulässige Zwischenverallgemeinerung dar, da beide Schaltungsteile nur unter dieser Bedingung gleichzeitig arbeiten können. Zur Überzeugung des Senats ist diese Streichung unschädlich, auch wenn die unabhängigen Patentansprüche dadurch Varianten umfassen, die technisch nicht sinnvoll sind. Im Gegenteil wäre es eine unnötige Überfrachtung der Patentansprüche, wenn darin überflüssige Angaben genannt würden, die der Fachmann stillschweigend voraussetzt.

605 Auch soweit die Klägerin gegenüber den Hilfsanträgen I, Ia, sowie II geltend macht, diese seien unzulässig, da die geänderten Fassungen in den ursprünglichen Unterlagen nicht offenbart seien, führt dies nicht zum Erfolg.

612 Gegenüber dem Hilfsantrag III weist die Klägerin zwar zurecht darauf hin, dass die beanspruchten Bypass-Schalter gemäß den Figuren 9 und 10 nicht in den DC/DC-Wandlern angeordnet sind, sondern in den PV-Paneelen. Jedoch zeigt die Figur 11 eine Anordnung der Bypass-Schalter in einer sogenannten "junction box", die auch die typischen Schaltungselemente des DC/DC-Wandlers aufnimmt. Jedenfalls aus der Figur 11 entnimmt der Fachmann daher eine Anordnung der Bypass-Schalter in den DC/DC-Wandlern.

613 Zudem geht die gegenüber der erteilten Fassung in die unabhängigen Patentansprüche gemäß Hilfsantrag III zusätzlich aufgenommene Formulierung auf den erteilten Patentanspruch 7 (zugleich ursprünglicher Patentanspruch 17) zurück. Wären die Zulässigkeitsbedenken hinsichtlich der mit dem Hilfsantrag III gegenüber der erteilten Fassung vorgenommenen Änderungen berechtigt, wären diese ohnehin unbeachtlich, da sie bereits in den erteilten Ansprüchen vorlagen (BGH Urteil vom 27. Oktober 2015 - X ZR 11/13 "Fugenband").

614 III. Zum geltend gemachten Nichtigkeitsgrund der fehlenden Patentfähigkeit

615 Das Patent ist für nichtig zu erklären, da es in den verteidigten Fassungen nach dem Hauptantrag und nach allen Hilfsanträgen gegenüber dem Stand der Technik gemäß der Druckschrift NK1 (Walker, G. R.; Sernia, P. C.: "Cascaded DC-DC Converter Connection of Photovoltaic Modules”) in Verbindung mit dem Fachwissen des Fachmanns nicht auf einer erfinderischen Tätigkeit beruht (Art. II § 6 Abs. 1 Nr. 1 IntPatÜG i. V. m. Art. 138 Abs. 1 Buchst. a), Art. 52, 56 EPÜ):

616 Hauptantrag

617 Der Gegenstand des erteilten Patentanspruchs 1 ergibt sich für den Fachmann in naheliegender Weise aus der Druckschrift NK1:

618 Aus der Druckschrift NK1 ist hinsichtlich des Gegenstandes des erteilten Patentanspruchs 1 (Hauptantrag) zumindest folgendes bekannt.

619 A distributed power harvesting system

621 comprising:

622 1.1.1 a plurality of DC power sources;

639 the converters are buck - boost converters

641 each comprising a buck - boost converter, a controller and a circuit loop setting the voltage and current at the input terminal of the buck -boost converters according to predetermined criteria;

645 wherein, in response to the MPPT part and current or voltage at the output terminals, the controller activates either the buck converter or the boost converter or activates the buck converter and the boost converter together,

652 Hilfsanträge I sowie Ia

653 Da die Patentansprüche 1 gemäß Hilfsantrag I sowie Hilfsantrag Ia gegenüber dem des Hauptantrags nicht geändert sind, kann auch diesen Hilfsanträgen nicht stattgegeben werden.

654 Hilfsantrag II

655 Der Gegenstand des Patentanspruchs 1 sowie das Verfahren gemäß Patentanspruch 8 gemäß Hilfsantrag II ergeben sich für den Fachmann in naheliegender Weise aus der Druckschrift NK1.

656 Der Patentanspruch 1 gemäß Hilfsantrag II unterscheidet sich von der erteilten Fassung dadurch, dass nach dem Merkmal 1.4 eingefügt ist:

657 1.4a^{Hi II} so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string.

658 Entsprechend folgt gemäß Hilfsantrag II auf das Merkmal 8.3 des Patentanspruchs 8 das Merkmal:

659 8.3a^{Hi II} so that an output current and voltage from the buck plus boost converter (305, 405, 505, 605, 705) are responsive to requirements of the serial string.

660 Wie bereits unter Gliederungspunkt A I 4. k) dargelegt, fließt ausgangsseitig durch alle DC/DC-Wandler derselbe Strom, der sich abhängig von der Summe der aktuellen Summenleistung der in Reihe geschalteten DC/DC-Wandler sowie in Abhängigkeit von der DC-Busspannung ergibt. Die jeweiligen Ausgangsspannungen der einzelnen DC/DC-Wandler ergeben sich in Abhängigkeit von dem gegebenen ausgangsseitigen Strom sowie in Abhängigkeit von dem durch den MPPT des betreffenden DC/DC-Wandlers eingestellten Leistung.

661 Somit stellt die Angabe gemäß Merkmal 1.4a^{Hi II} bzw^. 8.3a^{Hi II} gemäß der erteilten Fassung keine Einschränkung dar. Vielmehr handelt es sich um Wirkungen, die sich aufgrund physikalischer Gegebenheiten von selbst einstellen.

662 Im Übrigen treten die genannten Wirkungen selbstverständlich auch bei dem aus der Druckschrift NK1 bekannten System ein.

663 Hilfsantrag IV

664 Der Gegenstand des Patentanspruchs 1 sowie das Verfahren gemäß Patentanspruch 7 gemäß Hilfsantrag IV ergeben sich für den Fachmann aufgrund seines Fachwissens in naheliegender Weise aus der Druckschrift NK1.

665 Der Patentanspruch 1 gemäß Hilfsantrag IV unterscheidet sich von der erteilten Fassung dadurch, dass das Merkmal 1.5 durch folgende Fassung ersetzt ist:

666 ^{Hi III} and in that the power delivery device (304, 404, 504) comprises a control part maintaining the input voltage to the power delivery device (304,404,504) at a predetermined value,

667 und sich daran folgendes Merkmal anschließt:

668 ^{Hi IV} and in that each of the plurality of buck plus boost converters (305, 405, 505, 605, 705) further comprises a safety module limiting the output to a preset safe value until a predetermined event has occurred.

669 Entsprechend folgt gemäß Hilfsantrag IV auf das Merkmal 8.3 des dortigen Patentanspruchs 7 das Merkmal:

670 ^{Hi IV} and wherein each of the plurality of buck plus boost converters (305, 405, 505, 605, 705) further comprises a safety module limiting the output to a preset safe value until a predetermined event has occurred.

671 Die Formulierung des Merkmals 1.5^{Hi III} stellt gegenüber der erteilten Fassung lediglich eine sprachliche Korrektur dar, die zu keiner von der zum Hauptantrag dargelegten Beurteilung führt.

672 Bei den Sicherheitsmodulen gemäß den Merkmalen 1.7^{Hi IV} sowie 8.5^{Hi IV} handelt es sich um die üblichen Überspannungs- bzw. Überstromschutzvorrichtungen, die der Fachmann zum Schutz von Betriebsmitteln routinemäßig einsetzt. Diese sind zumindest so lange aktiv bis der betreffende Störfall vorüber ist. Im Übrigen würde auch der Austausch eines Überspannungsableiters oder einer Schmelzsicherung die genannte Formulierung "predetermined event" vorwegnehmen.

673 Darüber hinaus handelt es sich bei der Hinzufügung eines Sicherheitsmoduls zu einem System mit den im erteilten Patentanspruch 1 genannten Merkmalen um eine bloße Aggregation, durch die keine über die Summe der Einzelwirkungen hinausgehende Wirkung zustande kommt.

674 Hilfsantrag III

675 Der Gegenstand des Patentanspruchs 1 sowie das Verfahren gemäß Patentanspruch 7 gemäß Hilfsantrag III ergeben sich für den Fachmann aufgrund seines Fachwissens in naheliegender Weise aus der Druckschrift NK1.

676 Der Patentanspruch 1 gemäß Hilfsantrag III unterscheidet sich von der erteilten Fassung dadurch, dass das Merkmal 1.5 durch folgende Fassung ersetzt ist:

677 ^{Hi III} and in that the power delivery device (304, 404, 504) comprises a control part maintaining the input voltage to the power delivery device (304,404,504) at a predetermined value,

678 und sich daran folgendes Merkmal anschließt:

679 ^{Hi III} and in that each of the buck plus boost converters (305, 405, 505, 605, 705) further comprises a plurality of switching devices (925, 1025, 1125), each of the switching devices (925, 1025, 1125) forming a current bypass to at least one DC power source (301, 401, 301, 601, 701).

680 Entsprechend folgt gemäß Hilfsantrag III auf das Merkmal 8.3 des dortigen Patentanspruchs 7 das Merkmal:

681 ^{Hi III} and wherein each of the buck plus boost converters (305, 405, 505, 605, 705) further comprises a plurality of switching devices (925, 1025, 1125), each of the switching devices (925, 1025, 1125) forming a current bypass to at least one DC power source (301, 401, 301, 601, 701).

682 Bei den in den Merkmalen 1.6^{Hi III} sowie 8.4^{Hi III} genannten Stromumleitungen handelt es sich offensichtlich um die üblichen Bypass-Dioden die in PV-Modulen ohnehin vorhanden sind, um zu verhindern, dass der Strom von gut belichteten Solarzellen schwächere oder teilweise beschattete Solarzellen "ausbrennt".

683 Im Übrigen handelt es sich auch bei der Existenz von Bypass-Dioden in einem System mit den im erteilten Patentanspruch 1 genannten Merkmalen um eine bloße Aggregation, durch die keine über die Summe der Einzelwirkungen hinausgehende Wirkung zustande kommt.

684 Hilfsantrag V

685 Auch der Gegenstand des Patentanspruchs 1 sowie das Verfahren gemäß Patentanspruch 7 gemäß Hilfsantrag IV ergeben sich für den Fachmann aufgrund seines Fachwissens in naheliegender Weise aus der Druckschrift NK1.

686 Der Patentanspruch 1 gemäß Hilfsantrag V unterscheidet sich von der erteilten Fassung dadurch, dass das Merkmal 1.4 durch folgende Fassung ersetzt ist:

687 ^{Hi V} wherein, in response to the MPPT part and current or voltage at the output terminals (610,612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together,

688 Entsprechend unterscheidet sich der Patentanspruch 8 gemäß Hilfsantrag von der erteilten Fassung dadurch, dass das Merkmal 8.3 durch folgende Fassung ersetzt ist:

689 ^{Hi V} wherein, in response to the MPPT part and current or voltage at the output terminals (610, 612), the controller (606) either selectively activates either the buck converter or the boost converter or, when a desired voltage at the output terminals (610, 612, 712) is similar to the voltage at the input terminals (614, 616, 716), activates the buck converter and the boost converter together.

690 Bei der durch die Merkmale 1.4^{Hi V} sowie 8.3^{Hi V} vorgenommene Konkretisierung handelt es sich um eine bei einem buck-bust converter selbstverständliche Eigenschaft, die der Fachmann bereits in der erteilten Fassung mitgelesen hat. Daher gelten die Ausführungen zum Hauptantrag auch für den Hilfsantrag V.

691 Hilfsanträge VI bis XXIII

692 Da in den Patentansprüchen 1 gemäß der Hilfsanträge VI bis XVII lediglich die Merkmale 1.4a^{Hi II}, 1.4^{Hi V}, 1.5^{Hi III}, 1.6^{Hi III}, 1.7^{Hi IV}, 1.8 in unterschiedlichen Variationen mit der erteilten Fassung zusammengestellt sind, ohne dass sich dabei eine über die kombinatorische hinausgehende synergetische Wirkung ergeben würde – gleiches gilt für die jeweiligen Verfahrensansprüche – kann keinem dieser Hilfsanträge stattgegeben werden.

693 Zur Begründung wird auf die vorstehenden Ausführungen zu den Hilfsanträgen II bis V verwiesen.

B.

694 Nebenentscheidungen

695 Die Kostenentscheidung beruht auf § 84 Abs. 2 PatG i. V. m. § 91 Abs. 1, 101 Abs. 1 ZPO.

696 Die Beklagte hat dabei auch die Kosten der Nebenintervenientin zu tragen, § 101 Abs. 1 ZPO. Der Beitritt als Streithelferin war zulässig, denn für die Annahme der Zulässigkeit der Nebenintervention im Patentnichtigkeitsverfahren reicht es jedenfalls aus, wenn der Nebenintervenient, wie hier unstreitig, ein Unternehmen ist, das durch das Streitpatent in seinen geschäftlichen Tätigkeiten als Wettbewerber beeinträchtigt werden kann (BGH, Beschluss vom 17. Januar 2006 – X ZR 236/01, GRUR 2006, 438 ff. – Carvedilol). Die Beklagte hat vor dem Landgericht Ansprüche wegen Patentverletzung gegen die Streithelferin geltend gemacht, so dass sie in Folge des Rechtstreits in ihrer geschäftlichen Tätigkeit beeinträchtigt sein kann. Nach der ständigen Rechtsprechung des Bundesgerichtshofs gilt die Streithelferin der Klägerin im Patentnichtigkeitsverfahren als deren Streitgenossin (BGH, Urteil vom 16. Oktober 2007 – X ZR 226/02, GRUR 2008, 60 ff. - Sammelhefter II).

697 Die Entscheidung über die vorläufige Vollstreckbarkeit folgt aus § 99 Abs. 1 PatG i. V. m. § 709 ZPO.