Science and Development Network (SciDev.Net)
Power quality is nowadays a major topic because of its significant impact on industrial and commercial power distribution systems. Most of the industrial and domestic devices are sources of power-quality degradation. They cause the current to vary disproportionately with the voltage and are therefore classified as nonlinear loads. As a result, the power utility supplying nonlinear loads has to meet required amount of reactive power serious problems associated with harmonics. In many commercial and industrial installations, electric power is distributed through a there phase four wire system with incorrectly distributed or uncompensated loads. Such systems may suffer from excessive neutral currents caused by nonlinear or unbalanced loads. This type of system has a problem.