In response to the integration of wind power into the multi terminal flexible DC transmission system,this paper proposes an additional adaptive frequency division control strategy on the basis of existing droop control,in order to fully utilize the wind power's participation in system frequency regulation ability and solve the voltage and frequency fluctuations caused by AC/DC grid connection faults in the DC system.The DC voltage deviation signal is taken as the input signal of the controller,and the input signal is divided into high-frequency fluctuation signal and low-frequency fluctuation signal through the first-order low-pass filter.According to the different frequency modulation capabilities of the wind power and DC transmission systems,the high-frequency fluctuation signal is added to the active power control loop of the converter at the rotor side of the wind turbine,and the low-frequency fluctuation signal is added to the external loop of the DC active power control,At the same time,voltage source converter(VSC)real-time power margin and DC voltage variation are introduced into frequency division control to adjust the time constant of the low-pass filter in real time and dynamically adjust the power output to improve system stability.A simulation model is built in PSCAD/EMTDC to verify the effectiveness of the proposed control strategy.
关键词
风力发电/下垂控制/自适应分频控制/高频波动/低频波动/协调控制
Key words
wind power generation/droop control/adaptive crossover control/high frequency fluctuation/low frequency fluctuation/coordinated control
维普
万方数据