±660 kV银东直流输电山东侧安全稳定控制策略

在交直流混联电网中,直流系统的双极闭锁对系统的安全性和稳定性影响较大。银东直流输电系统发生双极闭锁故障时,会引起特高压线路失稳、系统低频的稳定性问题,此时可通过采取切负荷的控制策略,确保系统稳定运行。文中通过研究±660kV银东直流输电系统山东侧安全稳定控制策略,提出了适用于大容量直流输入电网的安全稳定控制系统的策略研究方法、有效的切负荷优化技术及直流极闭锁判据;设计了主站、执行站分层控制模式以及按轮级切负荷的控制原理。该策略在山东电网的实际应用结果证明了其有效性。

Control Strategy of Security and Stability Control System on Shandong Side of Yin-Dong HVDC Transmission Project

In high voltage direct current(HVDC) and AC inter-connected electric networks,blocking of both poles of HVDC system has severe impact on stability of the overall system.When such block of both poles fault occurs in the Yin-Dong HVDC transmission system,stability problems such as destabilization of ultra high voltage AC transmission line and system low frequency may be triggered.To ensure stable operation of the system under such circumstances,quick and proper control strategy to shed certain load should be taken.Based on research on control strategy of ±660 kV Yin-Dong HVDC security and stability control system of Shandong side,specifically to electric network with huge HVDC power injection,practical research methods are proposed.These include effective optimal load-shedding techniques and HVDC blocking criteria for security and stability control system.The methods are based on the hierarchical control mode of main station and sub-station.The load shedding method follows the rounds and layers.The validity of the strategy has been justified by the application results in Shandong power gird.