Performance Analysis of Shunt Active Power Filter (SAPF) using p-q and d-q theories

Abstract

In general, large usage of power electronic based equipment introduces the harmonics in the distribution system. Hence, the nonlinear loads of industrial and domestic introduce the nonlinearity in the distribution system. Because of these nonlinear loads, the system voltage and current waveforms getting distort since the nonlinear loads introduces the harmonic content in the source consequently the power factor of the source reduces. These harmonics along with the less power factor causes various problems such as increases the losses in the transmission, distribution systems, overheating of transformers and motors, flickering effect in florescent tubes and operational failure of protective relaying etc. To reduce the harmonic currents in the power system and maintain the power quality, a Shunt active power filter (SAPF) based on p-q and d-q theories is used. Here, p-q theory has Clarke transformation for extracting the reference currents whereas the d-q theory consists of Park transformation along with the phase locked loop (PLL). The DC link voltage is regulated by using the PI and fuzzy logic controllers. Moreover, hysteresis current control technique is used to drive the voltage source inverter (VSI) and the shunt active power filter based on p-q and d-q theories for different DC link control strategies such as PI and Fuzzy under steady state and load variation is simulated in MATLAB.