Development of a New Cooling Control Device for Forced Oil-circulated Air-cooled Transformer

The principle and implementation of a new cooling control device for forced oil-circulated air-cooled transformer based on the chip microcomputer AT89C51 and Solid State Relay(SSR) is presented. The comprehensive switching control was carried out according to the transformer load and the transformer temperature. The strategy of the cyclic switching control is based on the balance of the accumulated operating time of the cooling unit group. The software design of the switching control module and the communication module is described. The device has other functions such as protection, fault locating, information display and communication. The results of its on-site application show that the device is of high operation reliability and control accuracy, and can prolong the service life of the cooling unit and save energy effectively.