一种多分区互联电网分布式无功优化算法

A distributed reactive power optimization method for multi-area interconnected power grid

电网互联进程不断加快和系统规模的不断扩大对互联电网无功优化计算提出了更高的要求。提出了一种基于子网边界节点等值注入功率的多分区互联电网无功优化分布式协调优化算法。基于电网监控分层分区的特点,通过建立保留分区间联络线的简化外网模型,将子网间边界向量相等的耦合约束转化为边界节点注入功率修正方程的等式约束。构造边界节点电压加权修正的外层协调环节,依靠等值注入功率和对应边界节点电压向量的数值更新与传递实现全网无功优化问题的分布式求解。该方法有效地降低了协调层的参与度,进一步提高了子网无功优化的独立性,符合无功优化和控制的本地性要求。对多个IEEE试验系统进行了数值仿真测试与分析,结果表明方法具有良好的有效性和适用性。

This paper presents a distributed optimization method to solve the optimal reactive power flow （ORPF） problem for multi-area interconnected power grid. A simplified external network equivalence method is used to implement the regional ORPF calculation of each sub-grid, and the inter-area coupling constraint is transformed into equality constraints of boundary bus as injection power modified equation afterwards. Therefore, the distributed solution of multi-area ORPF problem can be realized through the update and transfer process of equivalent injection power and its corresponding boundary bus voltage vector. The proposed method omits the tedious process of network equivalence and reduces the burden of coordination layer, which accord with the local feature of reactive power optimization and control properly. The numerical simulation results of several IEEE cases show that the proposed method is effective and suitable for online application.