Mitigation of Common Mode Voltage in Induction Motor Employing Multilevel Inverter

Abstract

Induction motor (IM) is a usually a constant speed motor. The Basic technique used to control and run the machine in variable speed drive application can be obtained by two level inverters, which can be controlled digitally with the help of microcontroller using sinusoidal pulse width modulation method. Thereby at the star terminal point of the load there is a voltage existed with respect to system ground. Hence it is defined as “common mode voltage”. Due to the common mode voltage, there is an electromagnetic interference that is induced. Thereby it causes lot of disturbance to the communication and electronic equipment’s, which are nearby to the system. The common mode voltage can be reduced with the help of high-level inverter that can be used for example two-level, three-level, four-level inverters etc. In this proposed system we are reducing the common mode voltage by using two level inverter & three level inverter. In this paper, mitigation of CMV is simulated through MATLAB and implemented by hardware setup.