强直弱交区域互联大电网运行控制技术与分析

Technology and Practice of the Operation Control of Large Power Grid Connected With Weak AC area

结合华中西南电网运行实际,提出在特高压工程建设过渡期系统强直弱交背景下,区域互联大电网的主要运行风险和控制措施。首先阐述了华中西南电网的强直弱交、直流送受并重的结构特征,分析了华中西南强直弱交区域互联大电网的主要安全风险,包括特高压交流联络线功率波动、特高压直流故障、直流受端交流系统故障和送端500 k V交流系统故障,对比了交直流故障影响。最后,针对当前的运行风险,提出防控措施,主要包括运行方式预控、配置和优化安全控制措施、优化电网第三道防线等。

Aiming at safe operation of Central and Southwest China power grids, this paper analyzes main operation risks of the interconnected regional power grids and proposes prevention strategies encountering strong DC and weak AC characteristics during transition period of UHV transmission projects. Structural characteristics of Central and Southwest China power grids are analyzed, such as strong DC and weak AC connection, UHV DC sending and receiving as one system. Main operation risks of interconnected Central and Southwest China power grids are analyzed, including power fluctuation in UHV AC transmission tie line, UHV DC faults, faults in both sending and receiving AC systems of UHV DC, and influences of various DC and AC faults are compared. Finally, this paper proposes prevention and control strategies against current operation risks, including preventive control of operation status, configuration and optimization of special protection systems, configuration and optimization of generation tripping, load shedding and splitting, to secure safe and stable operation of Central and Southwest China power grids.