Three-Phase Four-Leg Drive for DC-Biased Sinusoidal Current Vernier Reluctance Machine

• Published in: IEEE transactions on industry applications Vol. 55; no. 3; pp. 2758 - 2769
• Main Authors: Li, An, Jiang, Dong, Gao, Zihan, Kong, Wubin, Jia, Shaofeng, Qu, Ronghai
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.05.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Carrier-based pulsewidth modulation (PWM); Circuits; Copper loss; Data buses; dc-biased sinusoidal current vernier reluctance machine (DC-VRM); Direct current; DPWM; Electronic devices; Equivalence; Inverters; motor drive; Power efficiency; Power loss; Pulse duration modulation; Reluctance machinery; Short circuits; SVPWM; three-phase four-leg inverter; Topology
• DOI: 10.1109/TIA.2019.2896851
• ISSN: 0093-9994

This paper proposes a three-phase four-leg drive for dc-biased sinusoidal current vernier reluctance machine (DC-VRM). By adding an asymmetrical neutral leg to the conventional three-phase inverter, the dc field excitation current can be generated. Compared to the open-winding inverter (conventional drive topology), the three-phase four-leg inverter greatly reduces the number of power devices, and the asymmetrical neutral leg does not have short-circuit straight-through risk. The topology ensures that the stator current can flow in both directions and maximum torque per copper loss can be obtained in DC-VRM. Equivalent carrier-based pulsewidth modulation (PWM) strategy is proposed to produce the dc-biased sinusoidal current and maximize the dc bus utilization. The proposed carrier-based PWM has several different equivalent methods. Compared to the conventional DC-VRM drive, the power loss of the proposed drive with equivalent space vector PWM (SVPWM) can be reduced significantly and can be further reduced by discontinuous PWM minimum (DPWMMIN) in the rated condition. The proposed drive has the characteristics of low cost, high power density, and high efficiency compared to the conventional DC-VRM drive.