Modular Full-Bridge Converter for Three-Phase Switched Reluctance Motors With Integrated Fault-Tolerance Capability

摘要

In this paper, a novel modular full-bridge converter is proposed for three-phase switched reluctance motors (SRMs), which provides an advanced fault-tolerance solution for both the open- and short-circuit faults in switching devices. The proposed converter is composed of two standard six-pack switch modules, providing great benefits for industrial massive production due to the modular topology. Under normal conditions, bidirectional current excitation is developed in the proposed converter, where all the switching devices are actively involved, which makes full use of the switches and averages the heat dissipation for the heat sink design. When a switch fault occurs, the fault signature can be extracted by detecting the characteristics of phase currents and operation modes, and effective fault-tolerance strategies are further applied to achieve the fault-tolerance operation accordingly. Under switch open- circuit faults, the faulty phase is adjusted to unidirectional current excitation without degrading the motor performance. Under switch short-circuit faults, the motor can still work steadily with a single six-switch inverter module by easily reconstructing the proposed converter, without losing any phase windings. The simulation and experiments on a three-phase 12/8 SRM are carried out to validate the feasibility of the proposed converter and control techniques.