厂站二次设备多电源切换回路的改造分析

Analysis on Transformation of Multi-power Supply Switching Circuits of Secondary Equipment in Power Plants and Stations

为提高部分厂站二次设备的供电可靠性,需要采用多电源切换回路,而多电源切换回路的设计缺陷会对负荷电压稳定性和电源系统造成影响。为此,结合一个采用二极管进行双电源切换回路的实例,通过现场试验分析找出电源切换回路导致两段直流母线互联的缺陷的原因,并提出了完善的改造方案,最后提出电源切换回路设计时需注意的各种问题及防范措施。现有的作业规范并无针对电源切换回路进行详细的检查,对此提出多项简单、可靠的验收措施,防范电源切换对负荷、对电源系统的不安全影响。

In order to improve power supply reliability of secondary equipment in power plants and stations,it is needed to adopt multi-power supply switching circuit,while design defects of multi-power supply switching circuit may cause impact on stability of load voltage and power source system.Therefore,combining one case of adopting diode for dual power supply switching and by means of field test,this paper analyzes and finds out reasons for causing defects of two sections of direct current（DC）bus interconnection by power source switching circuit.It presents an impeccable transformation scheme and proposes various problems need attention and precaution measures.In view of that existing job specifications do not involve in detailed check on power source switching circuit,it also proposes multi-item simple and reliable inspection measures so as to prevent unsafe impact on load and power source system from power supply switching.