A reduced switch extendable-level inverter-fed open-end winding PMSM drive

The advancement of multilevel inverters has led to an increase in efficiency and reliability. This paper demonstrates the design and implementation of a reduced switch extendable-level inverter-fed open-end winding permanent magnet synchronous motor (PMSM) drive. Unlike traditional multilevel inverter topologies, output voltage levels in the proposed inverter depend on the operating frequency of the switches. As the frequency of operation is very high, the levels in the output voltage reach infinity and hence the term extendable-level inverter. It achieves infinite voltage output levels, with a reduced component count. The configuration of the open-end winding enables the application of the AC voltage directly to the independent motor phases and hence achieves the merits of operation at a reduced input DC voltage. The proposed drive achieves a very high DC-link voltage utilization, reduced inverter switching losses, enhanced power quality, and excellent dynamic response using a single DC source and a minimum number of components. A comparative analysis of the proposed drive with different MLI-fed OEWPMSM drives in terms of the component count and total harmonic distortion is provided. FPGA-based improved sinusoidal PWM control of the proposed drive reduces execution time and enhances the control performance of the inverter. Dynamic characteristics of the proposed drive are provided for analyzing the dynamic response of the drive to a step change in load torque. The proposed drive is simulated using MATLAB/Simulink platform for theoretical analysis and evaluation. The experimental prototype is designed and implemented for validating the proposed drive operation.