The EMI improvement on active filter using common-mode noise circuits balanced method

This paper presents the electromagnetic interference (EMI) improvement on active filter using common-mode noise circuits balanced method. The main objective is to reduce the electromagnetic interference (EMI) by reducing the common-mode noise current being generated from the effect of PWM signal of active filter. For this reason, this common-mode noise current flows through the reference ground and generates the conducted noise emission flowing around the circuit. Thus, this paper suggests the common-mode circuit balanced method by modifying the impedance of common-mode circuit impedance. The result shows that the common-mode currents is cancelled themselves. From the experimental results, both the spectrum of conductive noise before and after improving is compared.