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考虑静态电压稳定性的电力系统无功电压优化控制 孙龙明 （连云港供电公司云台操作队 江苏 连云港 222000） Reactive Power Optimization of Power System Considering the Static Voltage Stability and Voltage Control Abstract: Reactive power optimization is not only an effective mean to ensure the power system operates securely and economically, but also one of the most important measures to reduce the transmission loss and improve the voltage quality. Since the operating variables include continuous and discrete variables, the optimization becomes very complex. Only considering active power loss as the objective in reactive power optimization not only overlooks the voltage quality, but also leads the system to run on limit state and significantly reduces the systems security and stability. The mathematical model of multi-objective planning has been established in this paper. The objectives are made up of active power loss and voltage stability margin. The weighting objective function is used here to transform the multi-objective problems into a simple target problem. At present, commonly used methods are non linear programming, linear programming, and intelligent algorithms. Genetic algorithm has no special requirements for the initial value, and can reach the best result, so this paper uses genetic algorithm for reactive power optimization. Keywords: Reactive power optimization ；Multi-objective model ；Genetic algorithm 摘要：无功优化是保证电力系统安全经济、稳定运行的有效手段，是降低系统网损、提高电压质量的重要措施。其控制变量既有连续变量又有离散变量，优化过程十分复杂。 传统的单目标优化模型容易使系统运行在极限状态，从而大大降低系统的安全性和稳定性。本文在传统无功优化模型的基础上，建立了以全网有功损耗最小和电压稳定裕度最大为目标函数的多目标无功优化模型。通过对目标函数加权建立妥协模型，使多目标问题转化为单目标问题。目前常用的、比较成熟的无功优化方法主要有非线性规划法、线性规划法、人工智能方法等。考虑到遗传算法对初值无特殊要求，并且可以得到全局最优点的特性，本文选择遗传算法作为无功优化的工具。 关键字：无功优化；多目标模型；遗传算法 1 绪论 1.1 课题研究背景和意义 所谓电力系统无功优化，就是指在给定的系统结构参数和负荷水平下，通过调节系统中的无功资源：发电机和调相机的无功出力、已装设的并联电容器和电抗器的投切组数、有载调压变压器的分接头档位等，使得电力系统在保证运行电压质量的条件下，达到运行网损最小的目标[1]。 1.1.1 无功功率对电力系统的影响 无功功率对电力系统的影响主要可以从电压和有功损耗两方面来考虑。 （1）无功功率与电压的关系 系统中无功的分布与电压之间存在着密切的关系。以简单输电线路为例，如图1-1所示： 图1-1 简单输电线路等效电路 考虑到高压线路R远小于X