杨铁峰 刘立华 孙桂军 王新想 严建海 邹学毅

摘 要：在电厂/变电站直流系统中，蓄电池组故障不仅会导致继电保护装置误动作，还会引发各类电气事故。为提高直流系统的供电可靠性，本文采用蓄电池组分段升压的方式，开展电厂直流系统（DC110 V和DC220 V）在线监测和稳压应急电源方案设计，以实现单组电池的多段组合式冗余供电，同时研制相关应急电源装置并进行了性能测试。测试结果表明，在不改变蓄电池组原有接线方式的情况下，该装置可以实现变电站直流系统母线在线监测，同时可以在蓄电池组中单节或部分电池出现故障时实现零切换时间冗余供电，有效提高了发电厂和变电站直流系统的供电可靠性。

关键词：电厂/变电站;直流系统;蓄电池;多段;冗余;供电可靠性

Abstract： In the power plant / substation DC system， the battery pack failure will not only cause the relay protection device to malfunction， but also cause various electrical accidents. In order to improve the power supply reliability of the DC system， this paper adopted the method of boosting the battery into sections， and carried out the online monitoring of the power plant DC system （DC110 V and DC220 V） and the design of the stabilized emergency power supply scheme， so as to achieve multi-section combined redundant power supply of a single battery， at the same time， the relevant emergency power supply device was developed and the performance test was carried out. The test results show that the device can realize on-line monitoring of the substation DC system bus without changing the original connection mode of the battery pack， and at the same time， it can achieve zero switching time redundant power supply when a single cell or part of the battery in the battery pack fails， and effectively improve the power supply reliability of DC systems in power plants and substations.

Keywords： power plant/substation;DC system;battery pack;multi-section;redundancy;power supply reliability

直流系统是变电站非常重要的组成部分，它的主要任务就是给继电保护装置、断路器操作、各类信号回路提供电源，此类设备在事故停电过程中及停电后的一段时间内仍必须保持供电，否则可能引起主要设备损坏、重要自动控制失灵或危及人身安全。直流系统的正常运行与否，关系到继电保护及断路器能否正确动作，会影響变电站乃至整个电网的安全运行。近年来，国内发生了多起由蓄电池组故障引发的变电站直流母线失压故障，造成信号中断、保护拒动等事故。

1 变电站直流系统保护

1.1 变电站直流系统介绍

站用直流电源系统包括交流输入单元、充……