水电群孤网后的安全稳定特性及控制策略

水电群通过远距离、超高压通道送电,大扰动后与主网解列而孤网运行时,系统可能面临一系列由频率控制及电压控制等交织在一起的安全稳定问题。文中结合四川电网的实际运行情况,基于PSASP和MATLAB软件建立了仿真模型并复现了四川电网水电群孤网运行事故。通过研究水电群孤网的高频—高压特性,探讨了水电群孤网运行方式下影响系统安全稳定的主导因素,提出了水电群孤网运行的安全稳定控制策略,并通过仿真验证了控制策略的有效性。

Security and Stability Characteristics and Control Strategies for Isolated Hydropower Groups

Power generation of the hydropower groups is integrated with power transmitted through long distance and extra high voltage transmission lines.Hydropower groups may be isolated from the outage of transmission lines and confront with such serious stability issues as frequency control and voltage control.Combining with the actual operation conditions in Sichuan power grid,the simulation model is built based on PSASP and MATLAB to reproduce the operation accidents of the isolated hydropower groups in Sichuan power grid.Main factors resulting in system instability under isolated operation mode are explored with studying high frequency and high voltage characteristic of the isolated hydropower groups.The security and stability control strategies are accordingly proposed.Simulations in Sichuan power gird verify effectiveness of the proposed control strategies.