基于双层功率分配的智能配电网协同优化策略

Collaborative Optimization Strategy of Smart Distribution Network Based on Two-layer Power Allocation

针对新能源出力的强随机性、间歇性影响配电网功率平衡问题,提出了一种融合多步贪婪策略改进的深度双Q网络(double deep Q network,DDQN)算法和一致性算法的双层功率分配策略,该方法在源荷波动情况下可自适应调整配电网各机组出力,保证功率调节的快速性和经济性。首先,基于“资源集群”的划分提出了分层分布式功率分配框架,将智能配电网功率分配问题分解为协调调度层和自治层功率优化分配模型进行求解。然后,协调调度层采用多步贪婪策略改进的DDQN算法来实现“资源集群”间的功率分配,自治层提出以成本微增量为一致性状态变量的功率动态分配方法。最后,典型智能配电网算例仿真结果表明,所提的双层功率分配策略能够在新能源波动情况下解决功率的优化分配问题;与多种方法相比,所提方法具有较快的收敛速度和较低的调节成本。

In response to the problem that the strong randomness and intermittency of the new energy power output affects the power balance of distribution network,we propose a two-layer power allocation strategy combining modified DDQN strategy incorporating multi-step greedy policy with consensus protocol.The proposed method can adaptively optimize the output of each unit in the distribution network under the fluctuation of source and load,and ensure the rapidity and economy of power regulation.Firstly,a hierarchical distributed power allocation framework is proposed based on the classification of“resource clusters”,and the power allocation of smart distribution network is decomposed into optimiza-tion allocation models of the coordinated scheduling layer and the autonomous layer.Secondly,for the coordinated scheduling layer,we apply the modified DDQN strategy with a multi-step greed policy to achieve power allocation among“resource cluster”;meanwhile,for the autonomous layer,we use a dynamic iterative power allocation method with cost micro-increment as the consistent state variable.Finally,the simulations on a typical smart distribution network ex-ample show that the proposed two-layer power allocation strategy can be adopted to solve the optimal power allocation problem under the new energy fluctuation.Compared with various methods,the proposed method can achieve a faster convergence rate and lower regulation cost.