Implementation of a New Electro MagneticInterference Filters Design to Diminish CMNoise

Abstract

This paper mainly deals with the Electro Magnetic Interference (EMI) in switching power supplies. The EMI consists of two sources of noise namely common mode and differential mode noises. Due to interference, the efficiency of the equipment reduces and sometimes the equipment may be damaged. To avoid this effect EMI filters are designed like Active and passive filters. Passive Electromagnetic Interference (EMI) filters are replaced by active EMI filters to deal with high-frequency noise interference. Based on the measurement of noise EMI filter is designed to avoid interference. Peak current mode control is mostly used for power factor correction. The constant output voltage is also maintained. The EMI filter together with the boost inductor has to attenuate the high frequency (HF) voltage component to the mains side of the converter. With it, the optimum switching frequency and ratio of the ripple and fundamental current amplitude with respect to volume and losses are found. Procedure for designing ac line EMI filters is presented. This procedure is based on the analysis of conducted EM1 problems and the use of a noise separator. Design of active EMI filters leads to optimal component values and eliminates CM noise over a wider frequency range.