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The increasing scarcity of traditional energy sources, environmental pollution is getting worse, and the imminent global transition to safe, reliable and environmentally sustainable energy system, wind power ushered in an important opportunity for development. In recent years, the global wind power rapid development, China has become the world new installed capacity of wind power countries. However, with the increasing scale of wind power, wind farms into the system can not be ignored. The doubly-fed wind generator is one of the mainstream models of wind power, the wind the randomness caused the power fluctuations and dynamic response under fault conditions, power quality, system voltage, frequency and power angle stability of need The in-depth study. Thus, the combination of the actual project, the doubly-fed wind turbine modeling, the port dynamic characteristics and power quality, run stability study. Modeling, summed up the wind power model chosen for different problems, doubly fed wind turbine control strategy commonly used, obtained only in port voltage of the wind turbine is relatively stable under better control effect conclusions. Secondly, to improve control strategies commonly used, presents a new control strategy, can automatically compensate for reactive power lines need to access system, network power, and to take full advantage of the characteristics of the double-fed wind turbine, wind farm factor controllable, and based on PSCAD / EMTDC platform to verify the correctness of the improved model. Again, considering the current abroad wind turbine the core control method and parameters are not readily available, and the optional verbose switch will reduce the efficiency of the simulation model, the comparative analysis of the doubly-fed wind turbine PSCAD / EMTDC detailed electromagnetic transient model and Matlab / Simulink average model reflects the dynamic characteristics of grid failure, indicating that the two models have better consistency. Accordingly drawn DFIG equivalent average model, to improve the efficiency of the conclusions of the transient simulation in PSCAD / EMTDC platform to establish. Simulation with examples to discuss the security capacity of the instance of the wind farm. The dynamic characteristics of grid, the first simulation the port characteristics analysis of wind turbines under normal and fault conditions. Discuss the increase Crowbar circuit wind turbine low voltage across the ability of the improvement in the role, proposed to improve the fault during the network side variable inverter control strategy, to reduce the wind turbine rotor protection short circuit from the power grid to absorb reactive power, depth mastered wind turbine running port characteristics provide a theoretical foundation. Second, the combination of the actual wind farm containing the local power grid, build a simulation model in PSCAD / EMTDC platform, two angles from normal and fault, considering the symmetry of the wind speed, wind farm capacity, changes in the clearing time, failure and dynamic load modeling factors, to study the impact of wind farms on local power quality and voltage stability, draw some meaningful conclusions, laid the foundation for further research related simulation.
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