Control and performance of a fully-digital-controlled shunt active filter for installation on a power distribution system

TLDR

Digital controllers can suffer time and phase delays that may degrade harmonic‑damping performance, despite their advantages over analog controllers. The study aims to design and implement a fully‑digital‑controlled shunt active filter based on voltage detection to damp harmonic propagation from line inductors and shunt capacitors, rather than compensate current harmonics. The authors develop a digital controller for a shunt active filter that uses voltage detection to terminate harmonics in a power distribution system. Laboratory experiments confirm the viability and effectiveness of the fully‑digital‑controlled active filter.

Abstract

This paper presents a fully-digital-controlled shunt active filter for harmonic termination of a power distribution system. The main purpose of the active filter based on voltage detection is not to compensate for current harmonics but to damp out harmonic propagation caused by line inductors and shunt capacitors for power factor correction. However, time and phase delays inherent in digital controllers might lead to unsatisfactory harmonic-damping performance although digital controllers are preferable to analog controllers. This paper deals with the design and implementation of a digital controller for a shunt active filter based on voltage detection. Experimental results obtained from a laboratory system developed in this paper verify the viability and effectiveness of the fully-digital-controlled active filter.