A control strategy for shunt active filter

Abstract

This paper describes a novel control strategy for shunt active filters the sinusoidal Fryze currents control strategy. The control strategy considers the presence of harmonics in the system voltage and load current simultaneously. Although the fundaments of the pq theory is used to better explain the proposed control strategy, it is not directly used, since the Clarke transformation (abc to /spl alpha//spl beta/0 transformation) is avoided. In fact, the fundaments of the pq theory is inserted in a minimization method - the generalized Fryze currents, which together with a robust synchronizing circuit (PLL control circuit), form a concise controller for shunt active filter. The shunt active filter provides current compensation, such that the compensated current drawn from the network is sinusoidal and balanced, corresponding to the fundamental positive-sequence component of the load current, plus an additional fundamental positive-sequence component to cover losses in the power circuit of the shunt active filter. Simulation results are presented to validate the control strategy.