交直流系统静态安全域刻画与运行裕度计算

Steady-state Security Region Characterization and Operation Margin Calculation of AC/DC Power System

静态安全域的应用能解决以往稳态潮流安全校验只能逐点判断、无法给出安全裕度的缺陷。针对高压直流输电工程投运量的增加对原交流系统运行控制的影响,在包含电网换相换流器（LCC）直流输电和电压源型换流器（VSC）直流输电的交直流稳态潮流计算模型基础上,计及交直流系统各项约束限值,完成交直流系统静态安全域的定义与描述,从而拓宽了静态安全域的应用范围。在分析边界面、静态安全域几何体和约束条件之间关系的基础上,给出了基于非线性优化方法的有效边界筛选方法、稳态运行点至有效边界距离的计算方法、运行点安全性判断方法和系统运行裕度表征方法,使静态安全域的求解与已有的方法相比能较为精确地反映系统的全局安全信息。最后的算例分析表明了该方法的可行性。

The application of steady-state security region can solve the disadvantages that traditional steady-state power flow safety verification can only judge point by point and cannot give a safety margin.Aiming at the increasing number of HVDC projects which are put into operation will affect the original AC system＇s operation and control,we definition and put forward a steady-state security region of AC/DC power system based on the power flow calculation model including LCC DC transmission and VSC DC transmission and the constraints of AC/DC power system,so as to extend the application scope of steady-state security region.At the same time,compared to the existing methods about characterization of steady-state security region,we present the method of effective boundary interfaces screening,the calculation of distances between steady-state operating point and the effective boundary interfaces,the operating point safety judging method and system＇s operating margin characterization using nonlinear optimization method after analyzing the relation between and steady-state security region geometry and constraints,in order to ensure that solving the security region can accurately reflect global security information of power system.Finally,a study case is given to illustrate the feasibility of the methods.