Performance evaluation of fuzzy controlled three and four wire shunt active power conditioners

The three phase active power conditioner presented in this paper aims to shape the three phase line currents into sinusoidal balanced waveforms in phase with their corresponding line to neutral voltages under practical operating conditions. A modified synchronous reference frame algorithm is adopted to detect the reference currents for the conditioner. A fuzzy logic based current control strategy is exploited to regulate the conditioner output current. The performance features of both the three and four wire conditioner types are analysed and compared for compensating systems supplying nonlinear loads. The viability and fidelity of the proposed approach is verified via simulation results for a set of operating conditions. The performance of the conditioners is evaluated by a unified power quality index.