风力发电系统低压穿越控制技术研究

Research on low voltage ride through control technologyof wind power generation system

风力发电系统所连电网常有故障发生,故障会导致电网电压跌落,从而引起风电机组大面积脱网,这给并网风电机组在网压故障时的运行能力提出了更高要求,因此,低压穿越控制技术研究显得日益重要。本文对双馈型风电变流器的控制策略和低压穿越要求进行分析,采用一种软硬件相结合的方法实现低压穿越控制,在电网故障时可对发电机定、转子电流进行有效抑制,保护了电机侧变流器,实现了低压穿越功能。仿真和实验结果表明,本文所提出的低压穿越控制技术能为电网故障时风力发电系统稳定运行提供保证。

There are often faults in the grid connected to the wind power system.The fault will cause the grid voltage to drop,cause the wind turbine to be disconnected from a large area,and put higher requirements on the operating capacity of the grid-connected wind turbine when the grid voltage fails.Therefore,the research on the low-voltage ride-through technology is increasingly important.This paper analyzes the rotor converter control strategy and low-voltage ride-through requirements.A combination of software and hardware is used to implement the low-voltage ride-through control technology.In the event of a grid failure,the stator and rotor currents can be effectively suppressed,the rotor conversion is protected,and the low-voltage ride-through function is achieved.The simulation and experimental results show that the low-voltage ride-through control technology proposed in this paper can ensure the stable operation of the wind power system in the event of a grid failure.