Research On Technology Of Doubly-fed Wind Power Generator System

With the continuous development of national economy and the continuous environment pollution, the need of renewable energy is increasingly becoming a new developing direction of human society. As with the highest power density, the minimum environment pollution and the widest application area, wind power is more and more becoming the most important part in wind power utilization. It will be of significance to alleviate energy crisis and improve environment by researching wind power generation technology deeply. Among various renewable energy forms, variable speed constant frequency doubly fed generator, which has relatively lower cost, higher power density and efficiency, is gradually becoming the main form in wind power generation area of renewable utilization. Some key technologies of the simulation system of doubly fed generator were deeply studied in this paper.The DC motor speed control system based on buck circuit has been deeply researched in the paper. As the speed input device of the simulation system of doubly fed wind power generation, the DC motor speed control system might be unstable, inaccurate and not quick response, the paper adopted the double closed-loop control strategy based on speed and current feedback, and the correctness was validated in Matlab simulation system.Simultaneously, the control system, including the speed feedback signal dealing circuit based on K80G - 1024 - BMC5, the DC current signal acquisition circuit based on LA-55 P, the optocoupler isolation circuit based on 6N137 and the IGBT drive circuit based on M57962L,was made and tested successfully, that could ensure the DC motor speed control system have a stable, accurate faster response to the given speed.The inverter system based on IPM intelligent power module has been deeply researched in the paper. As the excitation device of the simulation system of doubly fed wind power generation, the inverter system determined the performance of the whole system. Whether the amplitude and the frequency of the excitation current could be accurately output by the inverter system was the key index to measure the performance of the inverter system. The performance of the inverter system can be validated by observing the voltage waveform of the stator-side output. The harmonic could be effectively reduced by using the space voltage vector pulse width modulation technique. The correctness was validated in Matlab simulation system. Simultaneously, the control system, including pulse blocking circuit, pulse interactive-blocking circuit and the intelligent power module interface circuit, was made and tested successfully, that could ensure the inverter system output the excitation voltage accurately and reliably to the given amplitude and frequency at a relatively quick response speed.On the premise of the design of the whole scheme and the specific control strategy, the control system based on DSP whose model is TMS320F28335 was designed by the paper,and the main circuit and the control circuit were designed as modular structure design. The main program, interrupt service subroutine and function subroutine were written by the paper, and test sample of DC motor speed control system based on buck circuit and the inverter system based on IPM intelligent power module were built respectively. At last, the experimental results were analyzed by the paper.