计及随机性的多分布式电源接入中压配电网承载能力评估

Hosting capacity evaluation of distributed generators accessing a medium voltage distribution network considering randomness

电力系统的源侧和荷侧均具有随机性,影响配电网接入分布式电源的容量分析。为此,提出了一种考虑源荷随机性的中压配电网多分布式电源承载能力评估方法。首先,将分布式电源和负荷出力分解为可预测变量和随机变量,结合序贯蒙特卡洛模拟法,分别模拟时序周期内源荷随机生产模型。其次,在划分供电分区和简化源荷接入位置基础上,以各供电分区可接入分布式电源容量最大为目标,考虑传输容量、电压偏差、短路电流等约束,对配电网承载能力模型进行随机潮流求解。然后,以指标变化量和限值距离为衡量依据,确定多分布式电源有序接入策略,防止局部运行参数不优而导致配电网对分布式电源承载能力受限。最后,将该模型应用在中部某城市的区域配电网中,验证该方法的可行性和有效性。

Both the source and load sides of a power system have randomness.This affects the capacity of the distribution network in accessing distributed power sources.For this reason,a method for evaluating the carrying capacity of distributed generators in a medium voltage distribution network considering the randomness of power sources and loads is proposed.First,the outputs of distributed power sources and loads are decomposed into predictable and stochastic variables,and combined with a sequential Monte Carlo simulation method to simulate the source-load stochastic production model in the time period.Secondly,this paper makes a division of power supply partitions and a simplification of the source-load access location,with the goal of maximizing the capacity of each power supply zone to access distributed power sources and also considering constraints such as transmission capacity,voltage deviation,and short-circuit current to calculate the stochastic power flow with the distribution network hosting capacity model.Then,using the index variation and limit distance as the measurement basis,the multi-distributed power supply orderly access strategy is determined.This prevents the distribution network from being limited in power supply hosting capacity because of inappropriate local operating parameters.Finally,the model is applied to a regional distribution network in a central city to verify the feasibility and effectiveness of the method.