PSO-infused Speed Controller design for CHB MLI-fed heavy-duty IM drives with CMV and Bearing current mitigative study

The Voltage Source Inverter (VSI) powering the Induction Motor (IM) has become an industry standard over the past two decades due to its numerous advantages. However, these motors are susceptible to bearing currents, leading to premature bearing failures. In any Pulse Width Modulation (PWM) inverter, a definite common-mode voltage is present, primarily responsible for the bearing current. This current flows through parasitic capacitances formed between the motor frame and its winding. Implementing a Multi-level inverter configuration offers a potential solution to mitigate bearing currents by providing multiple voltage levels, thereby limiting the common-mode voltage. Furthermore, a novel PSO-based algorithm is proposed to control the speed of multiple induction motors powered by existing Cascaded H-bridge Multilevel inverters. The algorithm aims to evaluate the extent to which the tuning of the IM speed is achieved. Subsequently, a mitigative study for common-mode voltage and bearing current is presented, highlighting the advantages and limitations associated with the proposed novel speed-tuning algorithm.