基于SMES-SFCL直驱永磁风电并网故障穿越能力

Fault Ride Through Capability of Direct Drive Permanent Magnet Wind Power Generation Connected to Grid Based on SMES-SFCL

为提高永磁直驱同步风力发电机组功率输出的稳定性和低电压穿越能力,提出了采用超导磁储能-超导故障限流系统来平滑风电机组的有功输出,改善故障穿越能力。当电网故障时,电阻型超导限流器限制故障电流对网侧变流器的冲击,提高网侧变流器的无功输出能力;当电网电压正常时,超导磁储能系统通过吸收和释放功率来平滑风电机组的有功输出,抑制功率波动;当电网电压跌落时,超导磁储能系统吸收直流母线上的多余功率,抑制直流母线电压上升;同时通过控制网侧变流器输出无功功率以支撑电网电压。仿真结果表明了该方法的有效性。

To improve the stability of power output and the low voltage ride through capability of a direct-drive perma⁃nent magnet synchronous generator,a method of applying superconducting magnetic energy storage and superconduct⁃ing fault current limiting system is proposed to smooth the active power output from wind turbines and improve the fault ride through capability.When a grid fault occurs,a resistive superconducting fault current limiter is used to limit the impact of fault current on the grid-side converterand improve the reactive power output capacity of the GSC.When the grid voltage is normal,the SMES system is applied to smooth the active power output from wind turbines by absorbing and releasing power,thus suppressing the power fluctuation.When the grid voltage drops,the excess power on the DC bus is absorbed by the SMES system to avoid the rise of DC bus voltage.At the same time,the output of reactive power is used to support the grid voltage through the control of GSC.Simulation results show the effectiveness of the proposed method.