Fuzzy logic controlled shunt active power filter for power quality improvement

TLDR

Fuzzy control offers a linguistic approach that eliminates the need for a mathematical model. The study evaluates a fuzzy logic controlled, three‑phase shunt active power filter for compensating harmonics and reactive power in nonlinear loads to improve power quality. The filter uses an INTEL 8031 microcontroller to implement fuzzy logic that senses line currents, generates carrierless‑hysteresis PWM, and is benchmarked against a conventional PI controller. The fuzzy controller outperforms the PI controller in dynamic response, as confirmed by simulation and experimental results under steady‑state and transient conditions.

Abstract

The simulation and experimental study of a fuzzy logic controlled, three-phase shunt active power filter to improve power quality by compensating harmonics and reactive power required by a nonlinear load. The advantage of fuzzy control is that it is based on a linguistic description and does not require a mathematical model of the system. The fuzzy control scheme is realised on an inexpensive dedicated micro-controller (INTEL 8031) based system. The compensation process is based on sensing line currents only, an approach different from conventional methods, which require harmonics or reactive volt-ampere requirement of the load. The performance of the fuzzy logic controller is compared with a conventional PI controller. The dynamic behavior of the fuzzy controller is found to be better than the conventional PI controller. PWM pattern generation is based on carrierless hysteresis based current control to obtain the switching signals. Various simulation and experimental results are presented under steady state and transient conditions.