低压电网线损计算中的改进形状系数法

Improved load shape coefficient method in low voltage line loss calculation

为了提高低压电网线损计算的准确度,提出了基于等值电阻法和前推回代法的改进形状系数法。根据负荷形状系数的基本定义和代表日典型实测数据,对居民、商业和动力等终端用户的负荷形状系数进行了分析计算,借鉴前推回代法的思路,由终端用户到配电变压器低压出口,逐级前推各段线路的负荷形状系数和传输电量,再由配电变压器低压出口到终端用户,逐级回代计算考虑电压降的电量损耗。该算法克服了等值电阻法只考虑配电变压器出口负荷形状系数,假设各节点电压相等的缺陷,算例及管理系统的应用结果证明了改进形状系数法的有效性。

In order to improve the accuracy of low voltage line loss calculation, this paper devises a new method named Im- proved Load Shape Coefficient Method（ILSC）based on the equivalent resistance method and back/forward sweep algorithm. ILSC analyses and calculates the terminal shape coefficient of load such as commerce load, resident load and power end-user load according to the basic definition of ILSC and data of measured in the typical date of low voltage net. ILSC refers to the idea of back/forward sweep algorithm, and derives the shape coefficient of load and transmited energy from bottom to top to all the unknown trunk lines, and then from top to bottom. It calculated the voltage drop lost energy of all lines. ILSC overcomes the shortcomings of the equivalent resistance method, which only considered the top load shape coefficient in low voltage net and assume all the line voluge is the same value, the example and the application result of the line loss management system have proved the validity of ILSC.