风力发电机组低电压穿越测试与分析

随着风电在电力系统中的穿透率逐年上升,风力发电与电力系统之间的相互影响越来越大,电力系统对并网风力发电机组在电网故障下能不间断运行提出强制性要求。分析了直流卸荷电路的工作原理和拓扑结构,建立了直驱风电系统模型。机侧变流器采用改进的直接电流矢量控制策略,实现了发电机平稳高效运行;对网侧逆变器控制策略做了进一步改进,增强机组的低电压穿越能力。利用移动式低电压穿越检测设备对内蒙古某风场永磁直驱风电机组进行了现场测试,测试结果满足国网的风电低电压穿越运行要求。

Test and analysis of low voltage ride through characteristic of wind turbine generator system

With the increasing penetration rate of wind power in power system,the interaction between wind power and electric power system is more and more intense,and the mandatory requirement is developed for the continuous operation of wind turbine under grid fault.The working principle and topology structure of DC unloading circuits were analyzed,and the model of direct-drive permanent magnet synchronous generator (PMSG) system was established.Machine side converter adopted the improved direct current vector control strategy,achieving the smooth and efficient operation of the generator;the grid side inverter control strategy was further improved to enhance the ability of low voltage ride-through (LVRT) of system.Movable LVRT test device was used to perform field testing for PMSG system of a wind farm in Inner Mongolia.The test results meet the LVRT requirements of the national grid.