Energy converter for a renewable energy generator

An energy converter comprising:

• a first battery string and a second battery string, the first battery string including a plurality of battery switch modules configured for controlling connection of a plurality of battery modules to the first battery string, and the second battery string including a plurality of battery switch modules configured for controlling connection of a plurality of battery modules to the second battery string,
• wherein a first terminal of the first battery string is configured for being connected to a positive rail of a DC link of a power converter of a renewable energy generator via a first converter terminal,
• wherein a second terminal of the battery string is connected to a first terminal of the second battery string,
• wherein a second terminal of the second battery string is configured for being connected to a negative potential of the DC link via a second converter terminal,
• wherein a maximum sum of a voltage of the battery modules of the first and second battery strings is at least equal to a DC link voltage limit,
• wherein the battery switch module comprises at least two semiconductor switches configured for controlling connectivity of individual battery modules to the first or second battery string respectively,
• wherein a battery string controller is configured for controlling a status of the at least two semiconductor switches of the battery switch module, and
• wherein an output voltage of the first and second battery strings is configured for being controlled by one or more battery string controllers.

A method of controlling a DCDC converter connecting a DC power sources to one or more DC loads via a high frequency transformer, said DCDC converter comprising:

• a first converter module including at least two individually controllable battery modules electrically connecting said DC source to a first side of said high frequency transformer,
• a second converter module including a battery string including a plurality of individually controllable battery modules electrically connecting said one or more DC loads to a second side of said high frequency transformer,
• a converter controller providing control references to a string controller based on which said string controller is controlling connectivity of said plurality of battery modules of said second converter modules to said battery string,
• wherein said connectivity is established by controlling semiconductor switches in a battery switch module of the individual battery module of said plurality of battery modules.

A DCDC converter configured for connecting one or more DC power sources to one or more DC loads, said DCDC converter comprising:

• a first converter module comprising a plurality of first converter module switching modules configured for connecting a first set of converter terminals to a first side of a high frequency transformer;
• a second converter module comprising one or more second converter switching modules each electrically connected a second side of said high frequency transformer, the one or more second converter switching modules being electrically connected to at least one second converter terminal set;
• and
• a converter controller configured for controlling said first and second converter switching modules,
• wherein at least one converter switching module of at least one of said first and second converter modules is implemented as a one or more battery strings,
• wherein said one or more battery strings each comprises a plurality of series connected battery modules,
• wherein said battery modules comprising a plurality of connected battery cells and a battery switch module,
• wherein said battery switch module comprises at least two semiconductor switches configured for controlling connectivity of said battery module to said battery string, and
• wherein a battery string controller is configured for controlling said four semiconductor switches of said battery switch module.