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Indexed by:会议论文

Date of Publication:2017-01-01

Included Journals:EI、CPCI-S、Scopus

Page Number:7364-7369

Key Words:Virtual voltage vector; superposition principle; four-switch three-phase inverter; modulated functions

Abstract:The four-switch three-phase inverter (FSTPI) is the fault-tolerant topology of the six-switch three-phase inverter (SSTPI), and the maximum output voltage is limited in the linear modulation region. Therefore, an overmodulation strategy for FSTPI is presented, based on virtual voltage vector and superposition principle, in order to improve the utilization of the DC voltage, enhance the output capacity of the inverter and extend the operation range of induction motor. Compared with the traditional overmodulation strategy, the proposed strategy can make the inverter transit smoothly from the linear operation to the six-step operation with simple online computation, which is convenient for digital realization and can possess balanced output voltages. Accordingly, the relationship between SVPWM and carrier-based PWM in the overmodulation region for FSTPI is derived. The simulation results illustrate the validity and effectiveness of the theoretical analysis.