500 kV/220 kV混压同塔四回路最优相序研究

同塔多回线路相序的选择需对多项电气与电磁指标进行综合考虑和协同优化。以电网安全稳定运行为出发点，首先梳理了电气不平衡度控制指标，建立了一套以输电网络电能传输效率最高为优化目标，以各项电压和电流不平衡指标必须满足安全限值为约束条件的数学模型，并采用数值方法对混压四回路1 296种相序进行遍历求解，得到电气不平衡最优及次优的若干个相序方案；然后对电气不平衡优化相序的电磁环境指标、感应电压和感应电流指标进行了协同分析和评估；最终确定优化相序方案综合可行性和合理性。通过典型500 kV/220 kV混压四回路案例验证了模型和算法的有效性。

esearch on Optimal Phase Sequence of Quadruple-Circuit Transmission Line with Dual Voltage 500/220 kV on Same Tower

A number of electrical and electromagnetic indices need to be considered and collaborative optimized when selecting phase sequence for multi-circuit transmission line on the same tower. Targeting on safe and stable operation of power grid, different electrical unbalance indices are discussed first. Mathematic model is established targeting on optimal power transfer efficiency with various voltage and current safety constraints. The optimal and several suboptimal phase schemes are obtained by using enumeration method on 1296 different phase sequences for four circuit transmission line with mixed-voltage. In order to prove the comprehensive feasibility and rationality of proposed optimal phase schemes, electromagnetic environment index, inductive voltage and inductive current index are calculated and evaluated. Typical phase sequence optimization cases of four circuit transmission line with dual voltage 500 kV/220 kV prove the validity of proposed model and algorithm.