Harmonic reduction in low-cost power supplies

Power electronic loads inject harmonic currents into the utility system. The large increase of power consumption will inevitably lead to deteriorating power quality due to the popularity of switch-mode power electronic equipment. Designers must satisfy two requirements. First obtain nearly sinusoidal line currents to comply with the international standard IEC 1000-3-2, and second achieve low cost, high operating efficiency and reliability to be competitive in the marketplace. In this paper we analyze the way to reduce the size and cost of the passive filters and still provide compliance with the international harmonic reduction regulations for low-power and low-cost applications.