Three-phase robust series compensator for voltage disturbances

In this paper the problem of voltage disturbances compensation in a three-phase three-wire electrical industrial system is addressed. A robust synchronous-based control algorithm is proposed for both endogenous and exogenous voltage disturbances compensation. The compensator is made of series transformers fed by a PWM-voltage source inverter (VSI). The control system regulates to zero the d- and q- components of the fundamental negative sequence of the supply voltages and compensates their harmonic content, by means of a feed-forward and of a feedback action. The influence of the passive filter for the switching ripple, on the compensator performances, has been investigated. Numerical simulations validate the effectiveness of the proposed compensation strategy.