Efficient multiple-reference-frame controller for current-harmonic suppression with a shunt active power filter

This paper presents a control method based on multiple reference frames for tracking or rejecting periodic signals in the context of shunt active power filters in power systems. The proposed scheme allows recursive calculation when referring signals to reference frames rotating synchronously with harmonic space vectors; giving an accurate and efficient harmonic controller and avoiding most of the trigonometric functions. The description in this paper will focus on the controller basics, its implementation aspects and its performance. The scenario with grid-frequency variations will be considered to evaluate its adaptation capability.