Design and research of three-phase power electronic load

Based on back-to-back structure of two pulse-width modulated (PWM) voltage-source converters (VSC) combined by capacitor of DC side, three-phase power electronic load is presented. These two voltage-source converters are respectively simulation converter which links tested power source as simulated load through direct current control of AC side, and grid connection converter which combines grid to transform power from tested power source back to grid in regenerated model. In this case, besides the capability of simulating majority of practical loads, such as resistive loads, inductive loads, capacitive loads, function of three phase power electronic load has obvious effect of saving energy, moreover, advantages like swift dynamic response, practical utility and convenient management supply wide applicable prospect towards this device. From this paper, the basic topology of three phase power electronic load is described in detail; then control strategies of back-to-back voltage-source converters are presented; eventually simulation waves of both simulation converter and grid connection converter are given to show excellent characteristics of this system.