Design And Application Of The Direct Air Cooled Control System Of Heat-engine Plant

In the control of Heat-engine Plant, the Air Cooled Control is one way of saving water to cool the circulating water. The Air Cooled Control is different from traditional water cooled, but using the air to cool the steam from the turbine to make the steam heat to the air. The northern region of China, such as Nei Monggol and Shanxi, where is rich in coal resources, can provide sufficient fuel for large Heat-engine Plants, while is the areas of lacking water resource. At present China is still at the stage of coal-fired power is most used to power, so promoting air-cooling technology will effectively relieve the status, and at the same time, the direct air-cooling technology in three kinds of air-cooling technology has certain advantage in operation and maintenance and economic benefit. Above all, the direct air-cooling technology is important, and its development has great significance.According to the deviation of the steam turbine pressure actual value and setting value, the Direct Air Cooled Control system has the PID adjustment, and adjust the rotational speed of the fan timely, which can make its air-cooling ability to adapt to the change of the environment temperature and the steam turbine load, and which make sure the air cooled power plant can operate safely and economically. The paper describes some of the calculation, fan selection and optimization in the design of Direct Air Cooled Control system, focusing on the analysis of the ACC system control strategy, and through studying the PLC control of ACC system it can be achieved by DCS. This paper combines with the Evenk2*600MW project of DCS, and describes and explains the logic of the air cooled control system and the realization of logic in LN2000.