Common Mode Voltage (CMV) in Three level NPC VSI using Advanced Bus clamping methods:A Study

PWM inverters are highly used in motor drive applications in industries. The PWM switching produces common mode voltage (CMV) which in terms produces Common Mode current (CMC). This CMC can cause many adverse effects like EMI and bearing current. The different switching sequences have varying magnitude of common mode voltages. In this paper a comparative study of common mode voltage values of double bus clamping and hybrid bus clamping switching methods are made with conventional CMV in a Three level VSI. This comparative study further indicates an insight of CMV performance of various switching sequences. The Validation of the study is done using MATLAB simulation platform.