用可编程逻辑控制器(PLC)实现电力系统备用电源自投装置

在国内变电站自动化系统中，各继电保护单元一般都由各生产厂家自行研制，功能专一，其扩展性不强。当运行方式改变时，往往不能够灵活地适应，而备用电源自投装置在实际运行时，却要求适应系统灵活多变的运行方式。采用PLC技术，则可较好地解决上述问题、由于PLC可靠性和扩展性较好，支持软件也较丰富，因而增加功能较容易，可适用于未来可能扩展或产品来源较多的变电站自动化系统。文章介绍了一种采用C20系列PLC开发的适应于全分布式变电站自动化系统的备用电源自动投入装置的实例。

Realization of the auto power switch device in electric power system by programmable logic controller

In the national substation automatization system,each relay protectio n cell commonly is manufactured by fa ctories themselves.Its function is simple a nd expansibility is not better.While the running mode is changed,it some times can' t adapt neatly.Moreover,it has to adapt the flexible changeful running modes when the standby auto power switch devices are plunged into practice.A doption of PLC technology can solve a bove problems effectively.Owing to the PLC' s preferable reliability and expansibility,and it also can support abundance software,thus,it is easier to e nhance its function and it will adapt the substation automatization system which is likely to be e nlarged in future with more manufacture sources.An instance of the standby auto power sw itch device which adapts to fully dis tributed substation automatizatio n system is presented in the paper.PLC in C20series is adopte d to develop the device.