Power Quality Improvement Using Active Power Filter

Abstract

Power quality is defined set of parameters defining the properties of power quality as delivered to the user in normal operating conditions in terms of continuity of supply and characteristics of voltage (frequency, magnitude, waveform, symmetry) . Power quality term which is used to assess and maintain good quality of power at the level of generation, transmission, distribution and utilization of electrical power. Due to excessive use of power electronic converters and non-linear loads it is observed that power system voltage and current waveforms become non sinusoidal and thus produce waveform driven power quality issues. The devices at the consumer level draw non-sinusoidal current because of their non-linear characteristic. Some of the problems caused related to the voltage at PCC (point of common coupling) are harmonics, surges, spikes, notches, sag/dip, swell, fluctuations, glitches, flickering etc. Power quality improvement has become an important area of research in engineering especially in utilization system. Out of these problems harmonics is considered as main cause for various power quality issues. newlinePower electronic converters and loads are the main sources of harmonics and reactive power which affect the performance of the power system network. Voltage harmonics and related power distribution problems arise due to current harmonics produced by nonlinear loads. As nonlinear currents flow through electrical system and the distribution-transmission lines, additional voltage distortion is produced due to the impedance associated with the electrical network. The pollution of electrical power is severe at the utilization level and is caused by greater power loss in distribution, interference problem in communication systems, transformer overheating, neutral burning, nuisance tripping of protective device and sometimes result in operation failure of electronic equipment s which are more sensitive because it contains microelectronic controller system which works with very low energy level.