中文摘要：

随着风力发电装机容量的不断增大,风电在电网中所占比重也越来越高,这就要求并网风电系统应具有低电压穿透能力。在电网电压发生跌落的情况下,为了使风电系统保持并网状态,对电网进行支撑并穿越故障,文章提出一种准确的、快速的电网故障电压检测方法——正序电压检测方法。该方法能在电网电压发生故障下做出快速的、精准的频率自适应响应。该电压检测系统包括正交信号发生器（QSG）、正序分量计算（PSC）和锁相环（PLL）3部分,系统中应用了二阶广义积分正交信号发生器。系统的输入为电网电压,输出为实时的相位角、正序电压分量和故障信号。通过对系统研究和仿真,表明该系统在电网发生故障时可有效地检测到故障信号。

英文摘要：

Along with the increasing of wind turbines installed capacity and occupying a greater proportion in power grid,the grid wind power generator with low voltage ride-through is required.It is necessary to puts forward an accurate fast power grid failure voltage detect methods in order to keep wind power system on grid,and support grid to ride-through of transient faults when the grid voltage drop occurred.This paper presents a new method of positive sequence voltage detection,with a rapid,accurate,frequency self-adapting response.The proposed system is made up of the quadrature signal generator（QSG）,the positive sequence calculator（PSC） and the phase-locked loop（PLL）.The innovation is the use of a dual second order generalized integral quadrature signal generator.The system input is grid voltage,the outputs are real-time phase angle,positive sequence voltage component and fault signal.It is a very effective method on transient fault signal detection by simulation,experiment and system research.