Power Quality Improvement by Harmonic Reduction Using Three Phase Shunt Active Power Filter with p-q d-q Current Control Strategy

摘要

With the widespread use of power electronics devices such as rectifier, inverter etc. in power system causes serious problem relating to power quality. One of such problem is generation of current and voltage harmonics causing distortion of load waveform, voltage fluctuation, voltage dip, heating of equipment etc. Also presence of non-linear loads such as UPS, SMPS, speed drives etc. causes the generation of current harmonics in power system. They draw reactive power components of current from the AC mains, hence causing disturbance in supply current wave form. Thus to avoid the consequences of harmonics we have to compensate the harmonic component in power utility system. Among various method used, one of the effective method to reduce harmonic in power system is the use of Shunt Active Power Filter (SAPF). This Paper gives detail performance analysis of SAPF under two current control strategy namely, instantaneous active and reactive power theory (p-q) and synchronous frame reference theory (d-q) and their comparative analysis to justify one of the method better over other. In both method a reference current is generated for the filter which compensate either reactive power or harmonic current component in power system. In this paper, a current controller known harmonic current controller is described which is used provide corrective gating sequence of the IGBT inverter and thus helps to remove harmonics component.