计及源荷相关度类线性紧缩法的配电网有功无功协同优化

Active and Reactive Cooperative Optimization of Improved Quasi-linear Relaxed Distribution Network Considering Source-Load Correlation

随着分布式电源的高比例渗透,主动配电网的稳定性受到很大影响,因此主动配电网有功-无功协同优化至关重要。对此,提出一种计及源荷相关度类线性紧缩法(Quasi-Linear Contraction,QLC)的配电网有功无功协同优化方法。首先,基于相关性分析方法分析新能源出力以及负荷的相关度,给出源荷相关度概率约束,完善系统优化模型。然后,针对优化模型非凸非线性容易导致局部最优解问题,采用泰勒展开式求解分支电流的上下界并代入节点电压和功率流方程,完成主动配电网模型的类线性紧缩,再采用罚函数方法校正,当得出的解在缩小后的约束范围内时该解为实际最优解,当得出的解在紧缩的约束边界上时,在满足原有约束范围的前提下向外寻优,得到实际最优解。最后,通过Yalmip等仿真计算软件验证所提方法的稳定性、准确性以及有效性。

With the high proportion penetration of distributed power sources,the stability of active distribution network is greatly affected,so the active power and reactive power cooperative optimization of active distribution network is very important.In this paper,a Quasi-linear contraction(QLC)method for active and reactive power cooperative optimization of distribution network is proposed.First based on the correlation analysis method,the correlation degree of new energy output and load is analyzed,and the probability constraint of source-load correlation is given to improve the system optimization model.In view of the problem that the non-convex nonlinearity of the optimization model is easy to lead to local optimal solutions,the Taylor expansion is used to solve the upper and lower bounds of the branch currents and substitute them into the node voltage and power flow equations to complete the quasi-linear contraction of the active distribution network model.Then the penalty method is adopted,and the actual optimal solution is achieved.When the obtained solution is on the tight constraint boundary,the actual optimal solution is obtained by external optimization under the premise of satisfying original constraint range.Finally the stability,accuracy and effectiveness of the proposed method are verified by simulation calculation software such as Yalmip.