| The Variable-Speed Constant-Frequency (VSCF) wind power generation system with Doubly-Fed Induction Generator (DFIG), which has the advantages such as running in a bigger working wind speed, high efficiency of wind energy extraction, smaller rating of the excitation converter, low cost, and so on, has been applied widely. In this kind of wind power generation system, the control and design of the AC-excited power supply is of great importance. This paper deals with the control of dual PWM converter for the VSCF wind power generation system with DFIG.Base on the grid converter mathematical model and the principle of proportional resonant (PR) controller, a novel control strategy, which is called PR control, is proposed. This technique makes full use of the characteristic of PR controller in realizing zero steady-state error in AC input signal in stationary frame and advantage in low-order harmonic compensation. Compared with conventional double close-loop PI control, the PR technique requires neither complex rotating frame transformation nor decoupling or voltage feedback influenced by temperature and circuit parameter. Thus, the complexity of control algorithm implementation is reduced, in the same time robustness and power quality is improved. For rotor-side converter control, adaptive PR control strategy is proposed to improve the drawback of conventional stator field-oriented vector control based on PI controller, which is control performance influenced by motor parameters easily. Then, a 1.5MW wind power generation system on adaptive PR control is studied by simulation.Besides, coordinated control of dual PWM converter is studied in this paper. A combined control scheme– load current feed-forward control is proposed to reduce dc-bus voltage fluctuation caused by rotor-side power changes frequently. Simulation results show that on the combined control scheme, the electrolytic capacitor capacity can be reduced to enhance the wind power generation system reliability effectively.
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