Development Of A New Cooling Control Device For Air-cooled Power Transformer

The safety reliability and life-span of the power transformer is based oncondition of operation. The temperature among the condition is very important.Transformer temperature must be control with the cooling unit.The tradition cooling control device in the power transformer there is manyshortcomings: frequent starting motor and relay switch ageing and unablecommunication with dispatch automation etc.The principle and implementation of a new cooling control device for forcedoil-circulated air-cooled transformer based on the chip microcomputer AT89C51 andSSR is presented. The comprehensive switching control is carried out according to thetransformer load and the transformer temperature. The strategy of the cyclic switchingcontrol is based on the balance of the accumulated operating time of the cooling unitgroup. The software design of the switching control module and the communicationmodule is described. The device has other functions such as protection, fault locating,information display, communication and so on. The results of its on-site applicationshow that the device is of high operation reliability and control accuracy, and canprolong the service life of the cooling unit and save energy effectively.