Researches On The Control Method Of Grid-connected Wind Farm Via VSC-HVDC

With the gradual depletion of fossil fuels and the deterioration of the global environment, development and utilization of renewable energy has become a focus of global concern. At present, renewable wind power is the largest and most successful example. But wind power is intermittent and volatility, its incorporation is bound to have a significant impact on the grid, especially with regard to frequency and voltage on the grid. Therefore, control of grid-connected wind farms based on the VSC-HVDC method, the wind is of great theoretical and practical significance.Based on the model of doubly fed induction generator, the active frequency control method based on the traditional active frequency droop control method, the active frequency control method is designed, which is the active frequency control method, which is based on the difference method, which can adjust the active power and the combination of the active frequency control method and the battery energy storage system. Then with doubly fed induction wind generator as the object is given a new transient rotor current simulation method, and on this basis further derivation and simulation, and some conclusions are drawn: crowbar protection circuit of energy release more resistance, the fault current is small. Finally, the active frequency droop control method is designed through the dynamic adjustment of droop coefficient, and the frequency control performance of the battery energy storage system is better than that of the battery energy storage system. Using the new transient rotor current simulation method can improve the simulation precision of the rotor current, and further reveal the fault characteristics of the power system with wind farm, and provide a more scientific and reliable basis for the protection setting.