A lower switching noise two-legs three-phase inverter applying new type modulation scheme

Abstract

This paper mentions about a lower switching noise control method for two-legs three-phase inverter. Usually, six switch devices are necessary to construct three-phase inverter, one of two-legs type inverter can generate three-phase voltage. This type inverter uses voltage divide capacitors, and often uses rectified voltage source with ripple component. To switch control of the inverter, PWM method is generally used. But in the case of PWM measure, large switching noise peak components appear on the multiple numbers of the carrier frequency, and this causes noise interference problem to the peripheral equipment. For the purpose of reducing large switching noise components of two-legs three-phase inverter, this paper proposes a novel type switch control scheme. The proposed method improves delta-sigma modulator and also removes input voltage fluctuation effect simultaneously.