基于信息间隙决策理论的下垂控制直流配电网运行参考点优化方法

Operation Reference Point Optimization of Droop-controlled DC Distribution Networks Based on Information Gap Decision Theory

为有效考虑直流配电网中分布式电源(distributed generation,DG)出力和负荷随机性的影响,提出了基于信息间隙决策的直流配电网下垂控制运行参考点优化方法。首先,在DG出力和负荷为预测值的基准场景下,以节点电压偏离额定值方差最小为目标对下垂控制运行参考点进行优化;其次,对优化方案应对DG和负荷变化的能力进行评估,针对运行约束越限风险较大的时段,提出了基于信息间隙决策的运行参考功率下层调度模型,在保证节点电压相对于基准场景下优化结果的恶化值小于设定值的约束下,以最大化DG出力和负荷的波动区间为目标对运行参考点进行优化调整。仿真结果表明,所提出的优化模型能在降低传统鲁棒决策保守性的同时,有效提高直流配电网应对DG出力和负荷变化的能力。

In order to effectively solve the influence of distributed generation(DG) output and load uncertainty in the DC distribution network, an optimal method of droop control operation reference point in the DC distribution network is proposed based on the information gap decision theory(IGDT). Firstly, in the benchmark scenario with DG output and load as predicted values, the droop control operation reference point is optimized with the objective of minimizing the variance of node voltage deviation from the rated value. Secondly, the ability of the optimization scheme under the benchmark scenario to deal with the variation of DG output and load is evaluated. For the periods with high risks of the limit exceeding of the operation constraints, the lower-level optimization model of the operation reference point is proposed based on the IGDT. Considering the constraint that the deterioration of node voltage compared with the scheduling results in the benchmark scenario is less than the setting value, the droop control operation reference point is reoptimized with the goal of maximizing the fluctuation range of the DG output and load. Simulation results show that the proposed optimization model can reduce the conservatism of the traditional robust optimization and effectively improve the ability of DC distribution network to deal with the DG output and load changes.