基于多分类支持向量机的分布式发电系统并网保护

摘要

在配电网出现孤岛、故障等异常情况时，并网保护需要及时断开分布式电源系统与主电网的连接。文中首先分析了并网保护的功能与特点，然后提出了一种基于多分类支持向量机的智能型并网保护方案。该保护方案在传统二分类支持向量机的基础上，建立了并网保护的概率型多分类器模型，实现对扰动、孤岛和故障事件的检测。为了提高模型的泛化能力，采用 SVM-RFE 方法对特征进行选择。最后，从保护的可信赖性与安全性两个方面，利用仿真对所提智能型并网保护与常规保护的性能进行了对比。%When an abnormal event such as islanding or fault occurs in the distribution network,the distributed generation systems should be disconnected from the distribution network by the interconnection protection.This paper starts with the illustration of the functions and characteristics of the interconnection protection.Then an intelligent interconnection protection scheme is proposed based on mult-i class support vector machine(SVM).Based on the traditional binary SVM classifier,the proposed scheme is used to build a probability-based mult-i class classifier,to realize fault and islanding detection.To improve the generalizing ability of the classifier,SVM-recursive feature elimination (SVM-RFE) algorithm is utilized to identify the critical features.Finally,detailed simulation results are given to demonstrate the effectiveness of the proposed protection scheme over the conventional protections in terms of reliability and security.