分布式直流系统绝缘在线监测的研究

Research on Distributed On-line Insulation Supervision and Measurement for DC Systems

大型发电厂变电所直流系统绝缘在线监测和故障定位一直是人们关注的问题。本文在分析了现有绝缘监测方法后,提出了绝缘在线监测的综合判剧和有关技术,所提方法简单实用,检测灵敏度较高,对直流系统不会造成干扰,且与系统分布电容大小无关。目前所采用的集中式绝缘监测系统现场布线多,施工复杂,易受干扰,可靠性难以保证。为此,文中提出基于微机的分布式绝缘自动监测系统方案,重点介绍了该系统的实现方法、系统结构,以及主测控仪和现场智能监测仪的实现方法和功能要求,所提出的系统监测可靠性高,布线少,组态灵活。

Insulation monitoring and fault detecting in the DC system in large power plants and substations have been a concerning problem. After now available methods of insulation supervision and measurement are analyzed, a comprehensive judge method and technique concerned of online insulation supervision and measurement are presented. The presented method riS simple, practical, by which measurement sensitivity is high, and this method cannot bring disturbance into dc systems, the measurement result is not related with distributed capacitance in dc systems. With now available centralized insulation monitoring systems the field wires are many, and field construction is complex, and they are easy to be disturbed, and their reliability is hard to be guaranteed. This paper presents a scheme of distributed insulation automatic supervision and measurement systems based on microcomputers, and centers on discussion of the system structure and the design method, and the function and the design method of a major monitor and control device and field intelligent monitoring devices, the distributed insulation supervision and measurement systems have characteristics such high reliability, less wiring, flexible configuration.