Research On Air Cooling System Based On PLC Control

As an important secondary energy in modern society,electric energy is inseparable from the people's life.The quality of electric energy is directly related to the development of the national economy.As the most important equipment in the power system,the power transformer plays the role of converting voltage and transmitting power in the power system,ensuring stable and reliable operation of the power grid.As the scale of the power grid continues to increase,the transmission power continues to increase,and the load on the transformer is becoming heavier.In order to solve this problem,in addition to expanding the scale of the power grid,ensuring the safe and reliable operation of the existing power grid is also one of the important duties of the grid people.Especially in the summer when the heavy load brought by residential electrical appliances comes,the heat dissipation problem of power transformers poses great challenges to the safety of the power grid.Excessive operating temperature will directly threaten the life of the insulating oil and insulating parts inside the transformer.Reduce the load capacity and greatly shorten the operating life of the transformer.Under this background condition,the importance of the transformer radiator is highlighted.The traditional relay type air-cooled control box technology appeared in the 1960 s and has a history of 60 years.This method has many logical contacts,low degree of automation,and is prone to failure.It can no longer adapt to the current power grid unattended substation.Claim.In this paper,a new PLC-based transformer air-cooling control system is designed.A logic circuit based on Siemens S7-200 programmable controller is designed to replace the function of the traditional relay air-cooled control system.The control system can effectively avoid the problems of the traditional air-cooled control system.PLC based transformer air-cooling control is based on the top oil temperature,winding temperature and load of the transformer as the criterion for the start and stop of the cooler,and proposes a new temperature control scheme to control the top oil temperature and propose to operate according to the fan.The length of time automatically adjusts the long-running fan to ensure the balance of operation between the fans of each group,and can start the air-cooling system scheme one by one.In addition to the change of the main logic control,this paper also discusses the relay.select.The solid state relay is used toreplace the traditional AC contactor to cut the cooler to avoid arcing.The motor protector is used instead of the thermocouple relay to protect various types of motors.The system can meet the high degree of automation,low failure rate and no Manned to the requirements of the substation.The requirements of the human-controlled substation are the perfect substitute for the traditional air-cooled logic.In addition to these basic logics,it can also realize functions such as remote communication,signal uploading,and host computer monitoring.