特大型城市电网大停电的机理和预防对策探讨

A Discussion on Mechanism and Countermeasures of Blackouts in Super Megacity Power Networks

基于对历史上发生过的特大型城市典型大停电事件起因和发展过程的分析,指出危及特大型城市电网安全的重要因素。阐述了在输电网负载过重条件下受端电网发电机组状态调整过程中多种电气量相互作用可致使系统状态逐步恶化的电力系统内在的物理特性。结合大容量远距离输电受端电网以及间歇性电源渗透率增大的特点,分别从电网规划设计和运行控制两方面,讨论电网安全分析、安全评估和安全防御的薄弱环节,提出降低停电风险的对策和技术措施,并对电力系统安全三道防线的配置提出了新的阐述和建议。

Based on an analysis of the cause and developing process of blackouts in a super megacity power system, the key factors endangering the security of the system are pointed out. The power system intrinsic physical characteristic is expounded that in the overload condition of a power transmission grid in the receiving end grid, the interactions between various electrical variables can cause the system state to deteriorate gradually during the adjustment process of the generator units in the receiving-end grid. By referring to the characteristics of the receiving end grid in a long distance power transmission system with large capacity and the problems from increasing penetration of intermittent generation sources, the weak links of the security analysis, security assessment and security defense system are discussed in terms of power grid planning and operation control, respectively. Countermeasures to reduce blackout risk are presented. A new expatiation and recommendation on the configuration of three-precautionary lines for insuring the security of the power system is put forward.