Investigation Of Switched Reluctance Generator In Wind Power

With the development of economy and technology, power and environment problems are increasingly urgent. Renewable energy becomes a future trend. Wind power gets more attention as one of the clean and renewable energy. Under this background, wind power technology has become a research focus and an increasing number of countries devote to wind power research. Wind power generation uses nature resources efficiently as well as not pollutes the environment, so it’s a kind of ideal power generation sources. This paper introduces current state and prospect of wind power generation, compares different types of wind power generation system, makes sure the advantage of using SRG (Switched Reluctance Generator) in wind power generation.SRG, as a kind of new power generation equipments, has characteristics of simple structure, low cost, high-temperature resistance, fault-tolerant ability and good low speed direct-driven performance. It has great practical value in low speed direct-driven wind power generation. This paper mainly focuses on the application of SRG in wind power generation, which includes theoretical analysis and simulation research. Main work of this paper are listed as following.Firstly, this paper introduces SRG’s basic structure and operation principle, analyses the excitation and power generation process of SRG in detail, especially the expressions of phase current. Self excited SRG and separately excited SRG are compared. Based on the theoretical analysis, control methods of SRG are summarized.Secondly, magnetization curves corresponding to different stator and rotor position are achieved by using finite element method in electromagnetic field. Accoding to these curves, linear mathematical model of exterior rotor switched SRG is built based on Matlab/Simulink. Every module’s function and structure is studied in detail. By using, the simulation model of exterior rotor switched SRG is verified. Exterior rotor switched SRG’s power generation process is simulated as well, which is used to verify the correctness of Matlab/Simulink simulation model.Then, steady performance and transient performance of exterior rotor switched SRG are simulated based on the simulation model. Control strategy and output characteristics are studied. SRG’s power generation process and voltage stability might be influenced by some factors,such as exciting voltage, turn-on angle, turn-off angle motor speed and stabilizing capacitor. Influences from these factors are discussed. Meanwhile, SRG’s winding fault and winding phase fault are simulated, which helps to develop fault-tolerant ability.Finally, based on the simulation work, driving and controlling sample system of exterior rotor switched SRG is developed. Experiment platform is built and some research is finished. TMS320F2812 chip from TI company is the core of the designed driving and controlling system. Design of this system includes hardware circuit design and software design. Hardware design includes power converter, position sensor and controller circuit design. Software design mainly concentrates on DSP controlling program development. Hardware circuit and controlling software constitutes the driving and controlling sample system of exterior rotor switched SRG and controls the power generation system together. Related signals test, function test and power generation experiment are finished based on the exterior rotor switched SRG power generation platform. The correctness of theoretical research and developed experimental platform is verified based on the research results.