双馈风电机组低电压穿越能力的应用研究

近几年来，风电机组容量快速增长，为了维持电力系统的安全稳定运行和保证风电场并网安全，对风电场提出低电压穿越的要求是必要的。低电压穿越要求是电力系统功率平衡与频率稳定的需要，也是局部电网电压稳定及电压恢复的需要。为最大限度减少大规模风电接入系统对电网的影响，对风电机组提出了更高的要求，即风电机组具有一定的低电压穿越能力。介绍了变速恒频双馈风电机组的基本结构，建立了双馈风电机组动态数学模型。以Matlab/Simulink为仿真应用平台搭建了系统仿真模型，结合风电场低电压穿越能力要求的相关标准规定，针对不同电网电压跌落的情况下，仿真应用研究了变速恒频风电机组的低电压穿越能力，仿真结果表明:双馈风电机组在电网电压跌落时满足继续并网运行的条件，且为电网电压恢复提供了无功功率，提供的无功功率大小与电网电压跌落程度有关。

Study on the application of low voltage crossing capacity of doubly-fed wind turbine.

in recent years, with the rapid development of wind power unit capacity, in order to maintain the safe and stable operation of power system and to ensure the safety of wind power grid, it is necessary for wind farms to ask for low voltage across. The low voltage crossing requirement is the need of power balance and frequency stability of power system, and it is also the need of voltage stability and voltage recovery of local grid. In order to minimize the impact of large-scale wind power access system on the power grid, higher requirements are put forward for wind power units, namely, the wind power unit has certain low voltage crossing capability. The basic structure of the variable speed constant frequency doubly-fed wind turbine is introduced, and a dynamic mathematical model is established. Based on Matlab/Simulink simulation application platform of the system simulation model, combine with the low voltage across the wind farm capacity requirements of relevant standards, according to different grid voltage drop, the simulation application research on the variable speed constant frequency wind turbines ability of low voltage through the simulation results show that the doubly-fed wind power generator in the power grid voltage drop when meet continue to parallel operation conditions, and to provide reactive power to the grid voltage recovery, to provide the size of the reactive power related to the degree of power grid voltage sags.