Control Method of the Three-Phase Four-Leg Shunt Active Power Filter

This paper presents a novel all-digital approach applied to three-phase four-wire active power filter (APF), which is made up of three-phase four-leg voltage source converters. The controller just detects the main current and DC side capacitor voltage. Calculation method of the switch duty cycle is deducted on the base of mathematics model formed. This controller has fewer measurement, higher robustness and simpler calculation as comparing to traditional controllers. Simulation verify that the APF with proposed controller can compensate the harmonics effectively. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of the organizing committee of 2nd International Conference on Advances in Energy Engineering (ICAEE).