Implementation Of Adaptive Filter In Dstatcom

Abstract

Non sinusoidal current in a distribution system is mainly due to nonlinear characteristics of equipment such as adjustable speed drives, switch-mode power supplies, rectifiers, and others such type of loads. In most cases, nonlinear loads are represented either as a harmonic current source or a harmonic voltage source in practical applications and responsible for creating power-quality problems.        Mitigation of power-quality problems can be achieved by using passive or active filters; however, due to certain advantages of active filter (AF) with digital control, it is used for improving power quality. An improved version of a shunt-connected AF used in the distribution system is known as a distribution static compensator (DSTATCOM). It is used for compensation of current-related power-quality problems such as reactive-power compensation, harmonics elimination, and load balancing in power factor correction (PFC) mode and zero voltage regulation (ZVR) mode. Improved responses and capacity for transient overload even at a reduced voltage level are the major advantages of DSTATCOM. Various international standards such as IEEE and IEC have reported the guidelines of harmonics limit at the point of common coupling (PCC).