A novel buck-boost power converter is proposed to improve the performance of switched reluctance generator (SRG) system in an electric vehicle. In the proposed topology, the energy conversion part is formed by a buck-boost circuit and additional switches, with which, it is flexible to significantly boost the magnetization voltage and demagnetization voltage, thereby the output power range is improved and the power losses are reduced. The basic structure of the proposed converter is presented first and the attached operating modes are analyzed. The control strategy of the SRG system is then made to control the output voltage and the boost capacitor voltage. The simulation results show that compared to the conventional buck-boost converter, the proposed converter enhances the efficiency and reduces the power losses.

In this paper, a novel improved buck-boost power converter is proposed to improve the performance of SRG system. This new power converter originated from a conventional buck-boost converter. In the proposed converter, a buck-boost part and additional switches form a buck-boost energy conversion stage. With this energy conversion stage, it is flexible to significantly boost the magnetization voltage and demagnetization voltage thereby improving output power range and reducing power loss. Firstly, the basic structure of the proposed converter is presented and its several operating modes are analyzed. Then the control strategy of the SRG system is made to control the output voltage and the boost capacitor voltage. In the end, the simulation results on a three-phase 12/8 SRG drive demonstrate the eligibility of the proposed power converter and the feasibility of the control scheme. Compared to the conventional buck-boost converter, this improved buck-boost converter accelerates the excitation process and reduces the power loss.