Design Aspects of Inverter for 9-φ Pole Phase Modulated Induction Motor Drives

Abstract

In the traction applications, to attain the extended speed and torque ranges, researchers utilize pole-phase modulation (PPM) based MIM, which enables dynamic switching between different configurations like 12 pole, 3-phase for high torque and 4-pole, 9-phase for high speed in 9-φ IM. Despite this, challenges such as torque fluctuations and poor DC link utilization persist, prompting researchers to explore solutions by configuring a multilevel inverter (MLI). However, the focus has mainly been on different inverter configurations rather than on the design aspects. This paper aims to address this gap by presenting the design aspects of inverter configuration for PPM-based MIM drives. To address the torque fluctuations and poor DC link utilization of PPMIM drives the 3- φ SVPWM techniques are implemented in 9- φ IM, which results in the circulating currents. For this, the inverters are designed with bidirectional switches, such that the neutrals are isolated. The main objective of this paper is to give the design considerations of the DC link design, the switch selection of the 9-φ inverter, and the voltage and current rating of bidirectional switches. In addition to this, the switching loss, conduction loss analysis, and efficiency of the inverter are clearly mentioned. The proposed design for a 9- φ PPMIM drive has been implemented using Maxwell 2-D FEM analysis and Simplorer, incorporating a 5 hp motor model. To confirm the effectiveness of this design, a laboratory prototype of the 9-φ 5 hp PPMIM drive has been created. The drive is controlled by a TMS320F28379D microcontroller board, with the switching algorithm developed using DSP codes. © 2025 Elsevier B.V., All rights reserved.