A novel compensator for unbalanced three phase distribution feeders

Abstract

A new reactive power compensator to reduce the negative and zero sequence components caused by unbalanced loads and to adjust load bus voltages for three-phase three-wire and three-phase four-wire distribution feeders is presented. The new compensator consists of a three-phase voltage source inverter (to eliminate negative sequence components and adjust the load bus voltages) and a single-phase voltage source inverter (to eliminate zero sequence components). The use of dq phasor transformation control based on instantaneous value and sinusoidal pulse width modulation (SPWM) results in a system with fast dynamic response. The derivations of the mathematical model and computer simulations verify and explain the feasibility of this approach.