与VSC-HVDC连接的弱电网暂态频率偏移定量计算和调整方法

发布时间：2018-11-02 19:59

【摘要】：针对电压源换流器型的高压直流输电(voltage source converter based high voltage direct current,VSC-HVDC)连接弱电网时,若逆变站采用定有功控制方式,由于受端电网旋转惯量较小而产生扰动下暂态频率偏移较大的问题。该文采用了一种虚拟转动惯量控制策略,将VSC-HVDC的逆变站模拟为同步发电机,以增加受端交流系统的转动惯量,为受端电网提供动态频率支持。进而,建立了系统的频率响应模型,给出了最大暂态频率偏移计算公式,并提出了暂态频率调整方法。利用PSCAD/EMTDC软件对3种扰动下不同虚拟转动惯性取值时的系统频率响应进行了仿真比较,仿真结果表明,所提出的设计虚拟转动惯量的方法不仅能够较好的抑制扰动下频率的波动幅度,减小暂态频率偏移,而且所占用的逆变站容量较小。
[Abstract]:When the voltage source converter type HVDC (voltage source converter based high voltage direct current,VSC-HVDC) is connected to the weak current network, if the inverter station adopts the fixed active power control mode, Because of the small moment of inertia of the receiving power network, the transient frequency offset is larger under the disturbance. In this paper, a virtual moment of inertia control strategy is used to simulate the VSC-HVDC inverter station as a synchronous generator to increase the moment of inertia of the receiving AC system and to provide dynamic frequency support for the receiving power network. Furthermore, the frequency response model of the system is established, the calculation formula of maximum transient frequency offset is given, and the transient frequency adjustment method is proposed. By using PSCAD/EMTDC software, the frequency response of the system with different virtual rotational inertia values under three disturbances is simulated and compared. The simulation results show that, The proposed method of designing virtual moment of inertia can not only suppress the fluctuation amplitude of frequency under disturbance, but also reduce the transient frequency offset, and the capacity of inverter station is small.
【作者单位】：长沙理工大学电气与信息工程学院;
【基金】：国家自然科学基金项目(51277013) 湖南省研究生创新项目(CX2013B373)~~
【分类号】：TM721.1

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