Performance Improvement of Active Power Filter under Distorted and Unbalanced Grid Voltage Conditions

Abstract

In the case of balanced and undistorted supply voltages, shunt APFs can achieve current harmonic cancellation and give unity power factors. However, this is not possible when grid voltage is non-sinusoidal and unbalanced. In this paper, we first show that the harmonic suppression performance of the well-known p-q theory deteriorates in nonideal grid voltage conditions. A technique for alleviating the detrimental effects of a distorted and unbalanced grid voltage is proposed that uses a self-tuning filter with p-q theory. The proposed control technique gives an adequate compensating current reference even for non ideal voltage condition. The results of simulation study are presented to verify the effectiveness of the proposed control technique in this study.

Control of the shunt Active Power Filter under non-ideal grid voltage and unbalanced load conditions

“…STF was first used in order to estimate the phase angle of PWM converter outputs [4] and used in [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. In [6], the transfer function is obtained from the integration of the synchronous reference.…”

Analysis and simulation of line notching attenuation for a static excitation system in a power system

“…If the inductor is such that the voltage drop across it is about 3-4% of the phase voltage at the rated current, it is sufficient to reduce the notches at the transformer's secondary terminals to an acceptable level [6], [7], [11].…”

Design of Unified Power Quality Conditioner for Power Quality Improvement in Distribution Network

“…Some of the examples of implementing STF can be found in [9][10][11][12][13][14][15][16]. STF is mostly used as a filter to extract current harmonics in the controller of SAPF [9][10][11][12][13][14] and hybrid active power filter [15]. It is also proposed in the control of dynamic voltage restorer (DVR) with dc linked storage to improve its performance in case of weak grid condition [16].…”