A fast current control strategy of a PWM inverter used for static VAr compensation

This paper deals with the modelling and control of an advanced static VAr compensator (ASVC) system with a self-controlled DC bus which employs a three-phase PWM voltage source inverter. The ASVC system is modelled using the d-q transform and employs a programmed PWM voltage waveshaping pattern stored in an EPROM to simplify the logic software and hardware requirements. The inverter system can compensate leading and lagging reactive power supplied by the load connected to the supply. This model is used to design an efficient control strategy based on the control of the phase angle of the switching pattern. Simulated results obtained with Matlab are also presented and discussed to validate the model.