Study On Automatic Control Of The Whole Countercurrent Air Cooled Condenser System In Power Plant

Direct air cooled condenser is an effective method to solve the problem of power generation in drought and water shortage areas.Affected by the high temperature in summer,the unit's backpressure of direct air cooled condenser is generally higher than the water cooled unit.This leads to low efficiency of power generation.Moreover,under the condition of severe cold in winter,it is easy to cause the tube bundle of the radiator to freeze and plug,and threaten the safe operation of the unit.According to the useage of the whole countercurrent air cooled condenser in Aktobe of Kazakhstan,analysis the summer mode of air-cooled condenser heat transfer calculation model.And analyzed the factors that affect the back pressure of the air cooling unit.According to the content of the above analysis,air-cooled condenser standard mode of automation control technology were studied,obtained under turbine load stability,condenser heat transfer coefficient K is a constant,if need stability control back pressure P,two variables of the axial flow fan air flow q ?air inlet temperature t becomes key automation control parameters.Under normal operating conditions,the control system is controlled by adjusting the air flow rate and changing the group of heat exchange equipment automatically to control the exhaust pressure.Air flow can be adjusted by the speed of the fan(from 10% to 110%).In order to stabilize the unit back pressure,the spray flow rate and heat transfer model were studied,and the basis of automatic control was put forward,and obtained the relationship between back pressureP and spray water flow G and the relationship between spray water flow G and spray pressure P.On the other hand,in the winter cold environment,the control scheme of the anti freezing of the whole counter current air cooling system was studied,and the practical operation scheme was obtained.