Study Of Switched Reluctance Generator System Based On Four-Lever Power Converter

Switched reluctance motor (Switched Reluctance Motor, SRM for short) has a number of advantages, such as solid and simple structure, many controllable parameters and good fault-tolerant, and with the development of power electronics technology and the rise of wind power, the switch reluctance motor has been widely used not only in the field of transmission speed, but also has been more and more attention in the field of power generation,and has become a hot research at home and abroad in recent years.The asymmetrical half-bridge power converter is commonly used in switched reluctance generator (Switched Reluctance Generator, SRG for short) system. When the motor speed is low, its back-EMF will be lower than the generation voltage, leading to the phase current can not continue to increase in the power generation stage, and can not get the ideal current waveform, reduce the utilization of the motor and the conversion efficiency of the SRG system.Aiming at the shortcoming of the asymmetrical half-bridge power converter, In order to increase the output power of the SRG system, on the basis of the asymmetric half-bridge power converter, this paper presents a new power converter-a four-level power converter. In the four-lever power converter, the system uses two voltage source excited the motor windings in the excitation stage, while in the power generation stage, chose to use one voltage source or two voltage source based on the specific circumstances. Compared with the asymmetrical half-bridge power converter, when using the APC mode, the four-level power converter can increase the final excitation current of the phase windings, and get the ideal phase current waveform at a relatively low speed; when using the CCC mode, can achieve rapid excitation, reduce the motor excitation time, extend the power generation area of the motor, increase the output power of the switched reluctance generators, and improve the conversion efficiency of the SRG system. The CCC mode is commonly used in the control of SRG, so in this paper, we use the CCC mode.In this paper, the research object is four-phase8/6pole switched reluctance generator system, and simulate the different power converter drive the switched reluctance generator system by the MATLAB/m file simulation software, structure the experimental platform of SRG system based on the four-level power converter. From the simulate results, we can clearly find, when using the CCC mode, Switched reluctance generator driven by the four-level power converter system can reduce the time of the phase winding excitation, achieve rapid excitation, extend the power generation area of the motor, increase the output power of the system, also verify the correctness and the feasibility of the four-level power converter.