主动配电网分布式鲁棒优化调度方法

Distributed Robust Optimal Dispatch in Active Distribution Networks

分布式电源渗透率的增长使配电网运行的不确定性增大,加上分布式电源与配电网往往归属于不同利益主体,集中式的确定性优化调度方法已不能满足主动配电网的实际运行需求。考虑可再生能源出力的不确定性,建立了主动配电网分布式鲁棒优化调度模型。首先将配电网潮流方程进行简化以获得节点电压和注入功率之间的近似线性关系,进而推导出节点电压安全和线路电流安全约束的近似线性表达式;接着通过对偶优化理论将鲁棒优化调度模型转化为不含不确定变量的二次规划模型;然后将二次规划模型分拆成配电网侧和可控资源侧的优化子问题,采用交替方向乘子法对各子问题进行分布式优化求解。最后以修改的IEEE 33节点系统为例,验证了该方法的正确性和有效性。

With increasing penetration of distributed generators, uncertainty of distribution network operation increases. Moreover, distributed generators and distribution network often belong to different stakeholders. The centralized deterministic optimal dispatch method can no longer meet the actual operational requirements of active distribution network(ADN). Considering the uncertainty of renewable energy output, a distributed robust optimal dispatch model for ADN is established. Firstly, the AC power flow equation is linearized,so the approximate linear relationship between node voltage and injection power is obtained, and the approximate linear expression of node voltage security and line current security constraint is derived. Secondly, by using dual optimization theory, the robust optimal dispatch model is transformed into a quadratic programming model without uncertain variables.Then, the quadratic programming model is separated into sub-optimal problems of the distribution network side and the controllable resource side, and the sub-optimal problems are solved in a distributed way using alternate directional multiplier method. Finally, with the case study of modified IEEE33-bus system, correctness and effectiveness of the proposed method are verified.