The influence of ambient temperature change upon the direct air-cooling system control has been analysed from aspects of the turbine's backpressure control

the fans' electricity consumption

and the anti-freezing control etc.

a control strategy for direct air-cooling system being put forward to suit the ambient temperature change.The control mode based on fan speed is suitable for switching the fan row automatically in summer

but the control mode based on turbine's backpressure is more favorable for switching on the fan row in winter.In summer

the speed-setting controller of fans is suitable to adopt variable parameters

so as to strengthen the adjustment effect as the temperature raises.When the ambient temperature in winter changes from high to low

the anti-freezing protection of downstream fans could adopt sequentially the method of stopping the fans belonging to the row which triggers the protection

stopping fan rows adjacent to the upstream tube bundle block and increasing the set point of turbine' back pressure.When large temperature difference occurred in summer and winter

the fans in isolated and non-isolated streets have to be put into operation separately.In case of the temperature difference being small

the fans in isolated and non-isolated streets have to be put into operation stepwise;under low ambinet temperature in winter

the counter flow fans are suitable to put into operation stepwise.