Better performance for shunt active power filters

This paper proposes a time domain harmonic detection technique which is an improved a-b-c reference frame formula based upon the p-q theory with a positive sequence detector to solve the problem of bad performance of shunt active power filters (SAPF) under non-ideal mains. The improved formula needs fewer calculations than the conventional p-q theory. Moreover, it is very easy to implement this algorithm in a digital signal processor (DSP). Also the proposed method is compared to three detection algorithms which are the instantaneous reactive power theory (IRPT), synchronous reference frame (SRF), and synchronous detection method (SDM). The simulation results show better performance of the shunt active power filter with the proposed algorithm.