考虑分布式光伏电源接入模式的低压配电网不平衡线损计算方法

日益增加的户用光伏发电系统改变了配电网的潮流分布,同时对配电网的线损产生显著影响。为了便于量化分布式光伏电源(distributed photovoltaic generation,DPG)接入三相四线制低压配电网的运行经济性,文章以三相不平衡线损为研究目标,首先建立了适用于低压配电网平衡态和不平衡态的线损计算模型;通过引入DPG接入模式、位置及容量3种要素,建立DPG不同接入模式下的线损变化量模型;以此为基础,提出一种考虑DPG接入模式的有源低压配电网的三相不平衡线损计算方法。在进行计算时,所提方法既可利用实时电流数据,也可利用易采集到的有功电量数据进行计算。最后,以低压配电网的典型参数为例验证了该方法的准确性与可行性,说明此方法可为DPG单相、三相接入低压配电网的线损计算提供参考依据。

Calculation Method of Unbalanced Line Loss in Low-Voltage Distribution Network Considering the Access Mode of Distributed Photovoltaic Generation

The increasing number of household photovoltaic power generation systems has changed the power flow distribution of the distribution network, and at the same time has a significant impact on the line loss of the distribution network. In order to quantify the operating economy of distributed photovoltaic generation (DPG) connected to the three-phase four-wire low-voltage distribution network, this paper takes the three-phase unbalanced line loss as the research objective, and firstly establishes a balanced and unbalanced line loss calculation models suitable for low-voltage distribution network. By introducing three influencing factors of DPG access mode, location and capacity, the line loss variation model under different DPG access modes is established. A model for estimating the three-phase unbalanced line loss of the active low-voltage distribution network considering the DPG access mode is proposed. This method can be calculated by using both real-time current data and easily collected active power data. The accuracy and feasibility of this method is verified by taking typical parameters of low-voltage distribution network as an example, and the method can provide reference basis for line loss calculation of DPG single-phase and three-phase access to low-voltage distribution network.