| Recently, with the increasingly rigorous problems of energy source consumption and pollution, the employments of renewable energy sources have gradually been the inevitable trend of energy structure. Because of the merits such as convenient, clean, and flexible, wind power can feasibly satisfy the energy desire of the whole society, and the industry of wind power generation is flourishing in our state.The application of SRG in wind power generation occasion is concerned in this paper. And comprehensive investigation is carried out aiming at correlative control technology, including exhaustive theoretical analysis and simulation research.First, the history and development process of wind power utilization based on a large number of reference documents is summarized. And some kinds of samiliar variable-speed wind power generators are introduced. Then, a series of unique advantages of SRG are presented. And the remarkable achievements at home and abroad are proposed in order to clarify the research purpose further.Second, the basic working principle of SRG is described in detail. Deeply analysis of SRG nonlinear characteristic in actual operation is given, and three control modes of PWM, CCC, and APC are printed out. The generation period and voltage establish process of SRG is studied detaily. In addition, this chapter discusses the nonlinear mathematical models of SRG based on Fourier series and its actual working performance, and the simulation models on MATLAB platform are established.Third, the specific simulation researches about the application in current chop control situation of SRG are carried out. The control objective of output voltage ripples reduction is proposed through the comparing the open-loop operation results with closed-loop. And accordingly the design process of voltage feedback control system is exhaustive described. This part adopts classical PID controller and fuzzier PID controller as the voltage feedback controller to stabilize the output voltage and to restrain the ripples with the detailed elaboration of filter capacitor optimization, where the Equivalent Series Resistance is proposed. The simulation results testify that the control scheme with SRG can get ideal voltage quality under low or medium wind velocity range.Fourth, the angle position control method is proposed according to the special single-pulse working environment of SRG, which will cause the fail of fuzzier PID voltage controller. The closed-loop regulation system of excitation angles can control the turn-on and turn-off angles dynamically with the state change of machine, then winding current changes accordingly and hence the stable output voltage also can be guaranteed. Simulation results tesify that the closed-loop control strategy of excitation angles can be effective measures for the special working fields of SRG wind power generation system such as high velocity or heavy loads.Finally, the AC electric energy quality of SRG wind power system is emphasized, and the SVPWM over-modulation skill as technology support of the inverter part is proposed. The DC output terminal can obtain good voltage with the control system above, thus the quality of AC output mainly depends on the performance of inverter circuit. Simulation experiments verify that the SVPWM over-modulation technology can realize steady power supply for its ability of ensuring the excellent static and dynamic characteristics of the whole wind power generation system, in order to feasibly satisfy the user requirements.In this paper, the researches in some extent testify the feasibility and correctness of the whole proposed control methods, and offer the important guidance meaning in SRG wind power generation practical engineering application to some extent.
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