三相不平衡配电网不确定性分布式电源运行域仿射求解算法

高不确定性分布式电源(DG)的大量并网,给配电网安全、可靠运行带来了极大挑战。DG运行域可为DG的接入位置提供参考依据,并可实时监控配电网的运行安全,实现预警和预防性控制。提出了一种三相不平衡配电网中不确定性DG运行域的仿射求解算法。利用基于仿射算术的潮流计算求取节点电压关于DG出力不确定变量的近似线性表达式,综合考虑馈线容量、反向潮流以及电压表达式的安全范围等约束条件,构建三相不平衡配电网的DG运行域的优化求解模型,继而求取配电网中各DG的运行域边界。通过对改进的IEEE 123三相不平衡系统进行仿真,并与近似精确的仿真逼近法进行对比,验证了所提求解算法的准确性及高效性。

Affine Algorithm for Solving Dispatchable Region of Distributed Generators with Uncertainty in Three-phase Unbalanced Distribution Networks

There is a great challenge to the safe and reliable operation of distribution networks based on a large number of highly uncertain distributed generators(DGs)connected to the grid. The dispatchable region of DG can provide a reference for the access location of the DG and be used for real-time monitoring of safety of distribution networks to achieve early warning and preventive control. An affine algorithm for solving the dispatchable region of DGs with uncertain in three-phase unbalanced distribution networks is proposed. Firstly, the approximate linear expression of the node voltage on the DG output uncertain variable is obtained by the power flow based on affine arithmetic. Then, considering the constraints, such as feeder capacity, reverse current flow and safety range of voltage expression, the optimal solution model of dispatchable region is constructed. Finally, the dispatchable region boundary of each DG in the distribution network is obtained by solving the model. By the simulation of modified IEEE 123 three-phase unbalanced system and comparison with the approximate exact simulation approximation method, the accuracy and efficiency of the proposed methodology are proved.