| Doubly fed wind power generation system is increasingly concerned for its superior performance. The PWM converter which provides a suitable excitation current for the generator is one of the key components of doubly fed wind power generation system.Dual PWM converter in doubly fed wind power generation system is the research object of this paper. Firstly the mathematical model of DFIG is established. Based on the mathematical model and the control objective, control strategy for rotor side PWM converter is proposed, including voltage control strategy pre-grid and PQ decoupling control strategy in grid-connected operation mode. Based on an overall consideration of control objective and mathematical model, control strategy for grid side PWM converter is proposed.The hardware of dual PWM converter is designed. Allocation of DSP resources and interface between different hardware circuits is illustrated.Software design of the control system is explained in detail, including overall structure, flow charts and detail problem during the process of realizing the control strategy. Method for grid phase detection, stator flux observation, rotor position detection, PI regulation and SVPWM is described.Simulation platform for 11kw doubly feed wind power generation system is built. A squirrel induction motor dragged by frequency converter is used to simulate the prime motor, and a common wound induction motor is used to simulate the doubly fed induction generator. Experiment for dual PWM converter is carried out based on the platform. Voltage control experiment and output power control experiment for rotor side converter, rectifier experiment and inverter experiment for grid side converter are both included. Experimental waveforms are given in the paper. Experimental result has fully proved the validity of control strategies and satisfactory control performance has been achieved.
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