New Three-Dimensional Space Vector-Based Switching Signal Generation Technique Without Null Vectors and With Reduced Switching Losses for a Grid-Connected Four-Leg Inverter

Abstract

In this paper, the performance of the new three-dimensional space vector-based switching signal generation technique for a grid-connected four-leg voltage source inverter used as a shunt compensator is proposed. The shunt compensator can be used for reactive power compensation, harmonic elimination, load balancing, and neutral current elimination in a three-phase four-wire grid-connected system. It is shown through experimental studies that switching losses in the four-leg voltage source inverter are appreciably reduced to a maximum of 33% in three-dimensional space vector modulation without NULL vector as the number of switches controlled at any instant of time is six out of eight. The new proposed technique is compared with three-dimensional space vector modulation with null vector. Experimental results are given to show the validity of the proposed switching control strategy.