随着社会的发展、科技的进步，设备更新换代的周期日渐缩短，基于此背景下，

With the development of society and the advancement of technology, the cycle of equipment replacement is becoming shorter and shorter. Based on this background, many electrical control systems that use traditional relay switches as the main cause in the power industry are frequently started, and the relay switches are corroded and aging. The shortcomings of the failure are highlighted. As PLC (programmable controller) technology matures, on the one hand, it continues to develop simple, low-cost, ultra-small products, on the other hand, it turns to the development of large, multi-functional, serialized, standardized, and intelligent products. This article selects a part of the role of PLC (programmable controller) in power plant control (automatic control of oil-immersed transformer cooling system), based on Siemens PLC and its expansion modules as the core, supplemented by solid state relays, switches, contactors and other components The new type of control system is adapted to the original transformer cooler control system, eliminating the design deficiencies and defects in the original control system, greatly simplifying the system wiring, improving the reliability and automation of the device, and realizing a variety of operation controls The mode ensures the safe operation of the main transformer cooler.

With the development of society, the progress of science and technology, the cycle of equipment replacement is shortening day by day, based on this background, many electrical control systems using traditional relay switches due to frequent start-up, relay switch corrosion, aging and failure of the drawbacks highlighted. With the increasing maturity of PLC (programmable controller) technology, on the one hand continue to develop simple, low-cost, ultra-small products, on the other hand, to large-scale, multi-functional, serialized, standardized, intelligent product development. In this paper, the PLC (programmable controller) in the power plant control part of the role (automatic control of the oil-immersed transformer cooling system) research, based on Siemens PLC and its expansion module as the core, supplemented by solid-state relays, switches, contactors and other components of the new control system for the original transformer cooler control system, eliminating the original control system design deficiencies and defects, greatly simplifythed the system wiring, improve the automation of the device, realize a variety of operating control modes, The main variable cooler is guaranteed to operate safely.

With the development of society and the progress of science and technology, the period of equipment renewal is becoming shorter and shorter. Based on this background, many electrical control systems which use traditional relay switch as the main part in the electric power industry suffer from failure due to frequent start-up, corrosion and aging of relay switch. With the development of PLC (programmable controller) technology, on the one hand, it continues to develop simple, low-cost, ultra small products, on the other hand, it turns to the development of large, multi-functional, serial, standardized and intelligent products. In this paper, a part of PLC (programmable controller) in power plant control (automatic control of oil immersed transformer cooling system) is selected for research, based on Siemens PLC The new control system with its expansion module as the core, supplemented by solid-state relay, switch, contactor and other components is reformed for the original transformer cooler control system, which eliminates the design deficiencies and defects in the original control system, greatly simplifies the system wiring, improves the reliability and automation of the installation, realizes a variety of operation control modes, and ensures the cooling of the main transformer Safe operation of the.