GLOBAL SYNCHRONOUS PULSE WIDTH MODULATION SYSTEM AND METHOD FOR DISTRIBUTED GRID-CONNECTED INVERTER SYSTEM

摘要

The global synchronous pulse width modulation system includes main control unit and plurality of grid-connected inverters located at different geographical locations, wherein each grid-connected inverter is connected with a distributed power supply; each grid-connected inverter is connected with a grid through a point of common coupling; main control unit communicates with all grid-connected inverters through communication channels; main control unit receives information of grid-connected inverters and respectively sends a global synchronous signal containing global synchronous strategy to grid-connected inverters after determining global synchronous strategy; grid-connected inverters regulate the phases of their own pulse width modulation waves through global synchronous signal to enable pulse width modulation waves of grid-connected inverters to satisfy a phase difference of harmonic counteraction, so as to counteract harmonic current injected by grid-connected inverters into grid. Advantages include eliminating the disordered superimposition problem of harmonic current of the inverters and mutually counteracting harmonic current between distributed inverters.

主权项

1. A global synchronous pulse width modulation system for a distributed grid-connected inverter system, comprising a main control unit and a plurality of grid-connected inverters located at different geographical locations, wherein each grid-connected inverter is connected with a distributed power supply; each grid-connected inverter is connected with a grid through a point of common coupling; the main control unit communicates with all grid-connected inverters; the main control unit receives the information of the grid-connected inverters and respectively sends a global synchronous signal containing a global synchronous strategy to the grid-connected inverters after determining the global synchronous strategy; and the grid-connected inverters regulate the phases of their own pulse width modulation waves through the global synchronous signal to enable the pulse width modulation waves of the grid-connected inverters to satisfy a phase difference of harmonic counteraction, so as to counteract harmonic current injected by the grid-connected inverters into the grid.