摘要: 针对目前运行的大型电力变压器冷却控制装置存在的控制回路复杂、可靠性低、故障率高、控制误差大等问题，提出并研制了一种新型的变压器强迫油循环风冷控制装置。装置以西门子S7-200(CPU224)型PLC作为控制器构建了变压器冷却控制系统；系统以变压器顶层油温为被控量，提出了有差值裕度的投、切温度阀值的控制策略；提出了按冷却器的持续运行和累积运行时间自动均衡投切冷却器的控制方法；此外装置还具有通信及远方监视、故障定位、信息显示等功能。目前，装置已经在福建漳州莆美、角美220kV变电站投入使用。运行表明，该装置可靠性高、控制精确、并能延长冷却器组寿命，满足了大型变压器冷却控制装置智能化控制的要求。

关键字：变压器 冷却控制系统 可编程序控制器

ABSTRACT:To the problem exit in the cooling control device for large capacity transformer，such as the complicated control circuit，low reliability, high fault rate，large control error, the principle and implementation of a cooling control device for forced oil-circulated large capacity transformer based on PLC is presented in this paper．The device use siemens S7-200 PLC(CPU224)as controller, construct the cooling control system for transformer；the transformer temperature as the control system’s controlled variable，use control strategy of switch on and off value，which have margin in them，combine the accumulate operating time and continual operating time of cooling units，realize balanced，integrated auto control of cooling device．Beside this，the device has other functions such as，communication and remote surveillance，fault locating，information display．The devices have been used in Pumei and Jiaomei 220kV transformer substation．Zhangzhou．Fujian province．The results of operations show that the device is of high operation reliability, accurate control．Can prolong the service life of the cooling unit．The requirements of the intelligent control for large capacity transformer cooling device are satisfied．

Keywords：transformer；cooling control system；PLC