针对电力系统运行工况变化后动态等值系统响应精度不够的问题,提出一种基于多层次启发式动态规划(Global representation heuristic dynamic programming,Gr HDP)算法的动态等值方法。该方法在基于同调等值得到的模型的基础上,在等值边界上加入基于Gr HDP算法的动态补偿环节,实时补偿同调等值系统与原系统间动态特性的差额,从而实现精确跟踪原系统的动态特性。以10机39节点系统为例进行仿真研究,结果表明:在不同运行工况、故障方式和故障地点下,基于所提算法的动态等值系统相比传统的同调等值能更精确地跟踪原系统的动态特性。
To solve the problem of insufficient response accuracy for dynamic equivalence system after power system operating conditions change, this paper proposes a global representation heuristic dynamic programming (GrHDP)-based dynamic equivalence method. Based on the model obtained by coherency equivalents method, a dynamic compensation block based on GrHDP is added to the boundary of the equivalent model, which can compensate the dynamic response difference between the equivalent system and the original system. Therefore, it can accurately track the original system dynamic characteristics. Case study is undertaken on a 10-machine 39-bus power system. Simulation results show that the equivalent model obtained by proposed dynamic equivalence method can more accurately track the original system dynamic characteristics than that obtained by the coherency equivalents method under different operating conditions and fault locations. This work is supported by National Natural Science Foundation of China (No. 51529701).