含DCPFC的交直流混合系统多目标最优潮流研究

Multi-objective Optimal Power Flow Study of Hybrid AC/DC System With DCPFC

为了实现电网内部潮流的有效控制,对含有直流潮流控制器(DCPFC)的交直流混合系统最优潮流进行研究。首先针对电压源型DCPFC提出了一种基于等效电阻的外特性等效模型,据此利用传统牛顿–拉夫逊法推导出含有DCPFC的直流潮流计算方法。然后以系统网损和性能指标最小化为目标构建交直流系统多目标最优潮流模型,运用基于精英策略的快速非支配排序遗传算法(NSGA-II)优化该模型,得到均匀分布的最优解集。最后利用MATLAB验证该潮流计算方法的正确性和遗传优化算法的有效性,为交直流电网的潮流分析和实现DCPFC的优化配置奠定了良好的基础。

In order to achieve effective control of the internal flow of power grid,this paper studies the optimal power flow of the hybrid AC/DC system with DC power flow controller(DCPFC).Firstly,an external characteristic equivalent model based on equivalent resistance is proposed for voltage source DCPFC.The influence of the controller on the power flow distribution of the system is analyzed.With traditional Newton-Raphson method,a DC power flow calculation method based on equivalent resistance is derived.Then a multi-objective optimal power flow model of AC/DC system is constructed with the goal minimizing system loss and performance index(PI).The model is optimized with the fast non-dominated sorting genetic algorithm based on elite strategy NSGA-II to obtain the optimal solution set with uniform distribution.Finally,correctness of the power flow calculation method and effectiveness of the genetic optimization algorithm are verified with MATLAB,laying a solid foundation for power flow analysis of DC grid and optimal configuration of DCPFC.