Reducing Switching Losses in Brushless DC Motor Drive System by a Novel Soft Switching Inverter

In recent decades, brushless DC motors (BLDCM) have found increasing use in various industrial applications such as Electric Vehicles, Industrial Automation, Aerospace and Defense, Medical Equipment, and Renewable Energy Systems. This is primarily due to the numerous advantages offered by BLDCMs, including efficiency, reliability, low inertia, precise control, and high power density. However, traditional BLDCM drive systems powered by hard-switching pulse-width modulation suffer from multiple drawbacks, including Switching power losses, Electromagnetic interference (i) (EMI), Voltage and current stress, acoustic noise, and increased electromagnetic interferences. To overcome these issues, researchers have developed soft-switching inverters as an alternative. Unfortunately, these inverters come with their own set of drawbacks, like for example high voltage stress on the device, a large ripple of DC source voltage, and complicated control schemes. In the current paper, a novel inverter, which is resonant pole type, specifically designed for BLDCM drive systems is proposed. This inverter offers several benefits, including low switching power losses, reduced switching noise, a simplified scheme of the control system, and the absence of neutral-point voltage unbalancing issues. The operational principle of the proposed inverter is thoroughly studied, and simulation results are presented to validate the theoretical studies. This research aims to provide a more efficient and reliable solution for driving BLDCMs in various industrial applications.