An Integrated Multiport Power Converter With Small Capacitance Requirement for Switched Reluctance Motor Drive

This paper presents an integrated multiport converter with capacitance reduction for a switched reluctance machine (SRM). The conventional drive for the SRM is based on an asymmetrical H-bridge which needs large capacitor on the dc bus to absorb the transient energy caused by current commutation. The proposed topology consists of a multiport converter which introduces the dc bus capacitor as an extra port in addition to the input port and is integrated based on the switch multiplexing technique. With such a converter, the required capacitance can be reduced significantly by allowing an increase of the voltage ripple on the dc bus. In addition, the current commutation process can be accelerated with the high-voltage dc bus because the dc bus voltage is adjustable. The requirement of capacitance in an asymmetrical H-bridge and the proposed topology is analyzed in detail. The corresponding control method for the presented converter is introduced briefly as well. Simulation results in MATLAB/Simulink and experimental waveforms verified the feasibility of the proposed topology and its superior performance as compared with the asymmetrical H-bridge converter.