PV Sub-Generator Junction Box, PV Generator Junction Box, and PV Inverter for a PV System, and PV System

A photovoltaic (PV) sub-generator junction box for a PV system, comprising:

• a plurality of electrical terminals for connection to respective PV string lines of at least one series-connected PV module;
• and
• a sub-generator line terminal for connection to one of a PV sub-generator line of a remote central PV inverter and a PV sub-generator line of an intermediate PV generator junction box;
• an electronic control unit connected for data communication to a central control unit of the remote central PV inverter for exchange of data;
• and
• a power line modem configured to read and retrieve the data over the PV sub-generator line.

A photovoltaic (PV) generator junction box for a PV system, comprising:

• a plurality of sub-generator line terminals for connection to respective PV sub-generator lines of PV sub-generator junction boxes;
• a main DC power line terminal for connecting a PV main DC power line of a remote central PV inverter;
• at least one of a main circuit breaker for disconnecting the PV main power line and a collective circuit breaker for disconnecting a respective one of the PV sub-generator lines;
• and
• a data signal coupler connected in parallel to a respective circuit breaker of the at least one of the main circuit breaker and the collective circuit breaker, so that data fed over at least one power line modem into the respective PV sub-generator line and into the PV main DC power line is also able to be forwarded when the respective circuit breaker is in an open state.

A photovoltaic (PV) inverter for a PV system, comprising:

• at least one sub-generator line terminal for connection to at least one of a respective PV sub-generator line of a plurality of PV sub-generator junction boxes and a PV main DC power line of an intermediate PV generator junction box;
• a grid connection for connecting the PV inverter to a power supply grid,
• a central control unit for controlling the PV inverter and for transmitting data to the plurality of PV sub-generator junction boxes connected for data transmission to the central control unit;
• and
• at least one power line modem for feeding and retrieving the transmitted data over the at least one of the respective PV sub-generator line and the PV main DC power line.

A photovoltaic (PV) system, comprising at least one central PV inverter and a plurality of PV sub-generator junction boxes:

• the at least one central PV inverter, comprising:
• a plurality of sub-generator line terminals for connection to respective PV sub-generator lines of said plural PV sub-generator junction boxes;
• a main DC power line terminal for connecting a PV main DC power line of a remote central PV inverter;
• at least one of a main circuit breaker for disconnecting the PV main power line and a collective circuit breaker for disconnecting a respective one of the PV sub-generator lines;
• and
• a data signal coupler connected in parallel to a respective circuit breaker of the at least one of the main circuit breaker and the collective circuit breaker, so that data fed over at least one power line modem into the respective PV sub-generator line and into the PV main DC power line is also able to be forwarded when the respective circuit breaker is in an open state;
• and
• the plurality of PV sub-generator junction boxes, comprising:
• a plurality of electrical terminals for connection to a respective PV string line of at least one series-connected PV module;
• and
• a sub-generator line terminal for connecting one of a PV sub-generator line of the at least one central PV inverter and a PV sub-generator line of an intermediate PV generator junction box;
• an electronic control unit which is connected for data communication to the central control unit of the at least one central PV inverter for exchange of data;
• and
• a power line modem configured to read and retrieve the data over the PV sub-generator line.