Common-Mode Voltage-Reduction Method of 7-Phase BLDC Motor Control System

• Published in: Energies (Basel) Vol. 16; no. 5; p. 2097
• Main Authors: Son, Yung-Deug, Kim, Dong-Youn, Kim, Hyeong-Jin, Kim, Jang-Mok
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-03-2023
• Subjects: BLDC motor; Brushless motors; common-mode voltage; conducted EMI; Control methods; Control systems; Coordinate transformations; D C motors; Design and construction; Direct current electric motors; Electric inverters; Electric motors; Electric potential; interleaving PWM; Methods; Modulation (Electronics); Motor task performance; seven-phase motor; switching frequency; Voltage; South Korea
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en16052097

This paper describes a method for reducing the common-mode voltage in a seven-phase brushless DC motor (BLDC) drive. The conventional interleaved method used in the three-phase inverter system is extended and applied. The proposed phase-phase interleaved method is studied to apply the six-phase excitation method for controlling the seven-phase BLDC. The six-phase switching functions related with modulation index (MI) and interleaved angle are obtained, and the average of the common-mode voltage is derived mathematically. The proposed control method reduces the common-mode voltage generation by applying the optimal interleaved angle according to MI. The proposed method is verified by experimental results.