摘要
由于分布式电源输出功率的随机性与波动性,当分布式电源大量接入配电网后,传统的反时限过电流保护方案很难满足配电网保护选择性和速动性的要求。为此,文章通过研究数字反时限过流保护继电器,提出一种基于用户自定义特征的反时限过电流保护方案。保护方案将反时限继电器的特性常数(A)和反时限的类型常数(B)同继电器的时间整定系数、启动电流共同作为待优化的连续变量,并以最小故障电流时所有保护动作时间之和最小为目标函数,利用内点法求解保护的最优配置。方案保证了线路出口处故障时保护能快速动作,满足了配电网保护选择性和速动性的要求。最后,通过仿真分析,对保护方案进行了验证。
The access of distributed generations adds new sources to distribution network,which changes the grid structure. The traditional inverse-time overcurrent protection scheme is difficult to satisfy the requirements of selectivity and speed because of randomness and fluctuation of DG＇s output power. The digital inverse time overcurrent relay was considered here and a new protection scheme of inverse-time overcurrent protection based on user-defined characteristics was proposed in this paper. The proposed protection scheme considers the two relay characteristics constants（ A、B） and picks up current,time multiplier setting as continuous variable settings that can be adjusted. The main objective is to minimize the overall time of operation of relays considering the minimum fault current. Four parameters are optimized by using interior-point method to achieve the optimal configuration of the protection. It makes protective relays act instantaneously when fault occurs at line exit end and satisfies the requirements of selectivity and speed. Finally,verification of the protection scheme is carried out by simulation analysis.
出处
《电测与仪表》
北大核心
2017年第6期37-43,共7页
Electrical Measurement & Instrumentation
基金
河北省电力公司科技项目(SGTYHT/13-JS-175)
河北省科技支撑计划重点项目(12213913D)
关键词
有源配电网
分布式电源
用户自定义特征
参数优化
反时限过流保护
active distribution network
DG
user-defined characteristics
parameter optimization
inverse time overcurrent relays
