Improved Buck-boost Power Converter of SRG Drive

Abstract 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.