A new control strategy for static VAr compensators for minimum harmonic injection

A firing strategy for the force-commutated, static volt-ampere reactive (VAr) compensator is proposed. Minimization of harmonic currents injected into the AC system is achieved through numerical optimization of the firing angles. Two control methods are discussed and compared. The method is flexible and useful for fairly low switching frequency (about 15 pulses per half cycle). The resulting AC current harmonics are substantially lower than those of a comparable sinusoidal PWM or a programmed harmonic-elimination technique