Research On Parallel Control Strategy Of Switched Reluctance Generator

Switched reluctance generator(SRG),as a special generator completely free of rare earth materials,has many advantages such as simple and rugged structure and flexible switching between electric and power generation states.The application in power system has captured people’s attention.In many occasions,the electrical energy generated by a generator obviously cannot meet the demand of the load,and multiple generators are often required in parallel to form a large power generation system to ensure sufficient power supply capacity and the reliability of the system.In this regard,based on the analysis of the operation principle and control method of the SRG system,this paper studies the parallel control of SRG from the perspective of power distribution.This paper first obtained the flux linkage curve of SRG by means of experiment and fitting,and verified the built simulation model of SRG system.By analyzing the circuit structure of the parallel system,the influencing factors that caused the uneven output current of generators were obtained.Based on the introduction of common current-sharing control schemes and their basic characteristics,this paper focuses on the simulation analysis of the control effect of three active current sharing methods in parallel SRG system.Finally,the maximum value method is selected as the main current sharing control method,and its steady and dynamic control effect in multi generator parallel system is tested.For generators of different power levels,according to the thought of the average value method and the master-slave method,corresponding control schemes are also given,and the effectiveness of the control strategy is verified by simulation.Secondly,on the basis of the obtained efficiency characteristic curves of each generator,this paper establishes the efficiency expression of the parallel SRG system,and gives an efficiency-optimized current distribution control scheme based on differential evolution algorithm.According to the magnitude of the load current,the reference current of current distribution loop of each generator can be quickly adjusted and then the working point of each generator can be changed to achieve the optimization of the efficiency of parallel system.Compared with the traditional current sharing control scheme,it is found that the scheme makes the overall efficiency of the system improved.At the end of this paper,the experimental platform of the parallel SRG system is established to verify the correctness and effectiveness of the current sharing control and the efficiency optimization strategy.The results show that these two schemes have good control effects and practical significance.In addition,the use of wireless chips as a tool for digital communication between parallel generators,to a certain extent,gets rid of the wired constraints of the traditional CAN bus communication and saves the control cost.There are 67 figures,9 tables and 82 references in this paper.