基于静态安全域的交直流混联大电网关键线路辨识

特高压直流输电系统的相继投运导致电力系统运行特性改变,交直流混联大电网的薄弱环节将出现变化。为辨识出交直流混联电网中的关键线路,避免大停电事故的发生,提出一种基于静态安全域的交直流混联电网关键线路辨识方法。采用静态安全域分析方法构建交直流混联电力系统的静态安全域,考虑交流线路潮流越限与直流逆变站闭锁判据,结合支路潮流模型,提出适用于交直流混联电力系统的静态安全裕度计算方法。以静态安全裕度为指标,给出交直流混联电力系统的关键线路辨识流程。最后使用江西电网实际电力系统进行仿真分析,结果验证了所提方法的合理性和有效性。

Identification of critical lines in AC/DC hybrid large power grid based on steady-state security region

The successive commissioning of UHVDC transmission systems leads to changes in the operating characteristics of power system, the weak link in AC/DC hybrid power grid will change. In order to identify the critical lines in AC/DC hybrid power grid and avoid the occurrence of blackouts, a critical lines identification method based on steady-state security region for AC/DC hybrid power grid is proposed. The steady-state security region analysis method is used to construct the steady-state security region of AC/DC hybrid power system. Considering the power flow limit of AC line and the blocking criterion of DC inverter, the steady-state security margin calculation method for AC/DC hybrid power system is proposed combined with the branch flow model. The critical lines identification process of AC/DC hybrid power system is given with the steady-state security margin as an index. Finally, the simulation analysis is carried out on the actual power system of Jiangxi Power Grid, and the results demonstrate the effectiveness and rationality of the proposed method. This work is supported by National Natural Science Foundation of China (No. 51577075).