Patent ID: 9124136
Filing Date: 2015-09-01
Classification: H02J,Y02E

Abstract:
1. An inverter for a distributed generation system, the distributed generation system comprising at least one distributed energy source and at least one energy storage, the inverter comprising: a main transformerless DC to AC inverter to be coupled to the at least one distributed energy source, the main transformerless DC to AC inverter to provide a real power of the inverter and to provide a first portion of a reactive power of the inverter, wherein the main transformerless DC to AC inverter switches at a fundamental frequency; and at least one auxiliary transformerless DC to AC inverter in cascade with the main transformerless DC to AC inverter, wherein an output of the main transformerless DC to AC inverter is coupled to an input of the at least one auxiliary transformerless DC to AC inverter, wherein each of the at least one auxiliary transformerless DC to AC inverters to be coupled to one of each of the at least one energy storages and each of the at least one auxiliary transformerless DC to AC inverters to provide a remaining portion of the reactive power of the inverter, wherein the sum of the first portion of the reactive power from the main inverter and each of the remaining portions of the reactive power from each of the auxiliary inverters equals a total reactive power of the inverter for the distributed generation system, wherein the at least one auxiliary transformerless DC to AC inverter switches at a pulse-width-modulated frequency.