Reduced-rating Hybrid Active Power Filter Comprising Zero-sequence Transformer and Three-phase Three-wire Active Power Filter for Three-phase Four-wire Distribution System

A three-phase four-wire active power filter is proposed in this article that consists of a three-phase three-wire active power filter, zero-sequence transformer, and single-phase active power filter. The reference current for tracking the desired source current is based on the neural network (constraint anti-Hebbian rule algorithm). The three-phase three-wire active power filter compensates current harmonics and reactive power requirement of the non-linear load. A zero-sequence transformer and single-phase active power filter are used to mitigate the neutral current. The proposed hybrid scheme (three-phase four-wire active power filter) significantly reduces the volt-ampere rating of the active power filter and improves the performance under different utility voltage conditions. The simulation of the proposed three-phase four-wire active active power filter is carried out for different voltage conditions. Further, the MATLAB-simulated (The MathWorks, Natick, Massachusetts, USA) response of the three-phase four-wire active active power filter has been validated on a prototype of the three-phase four-wire active-active power filter. The experimental result obtained from the prototype verifies the effectiveness and viability of the proposed scheme.