Patent ID: 8682526

Claim:
An automotive air-conditioning system configured to implement a sub-critical refrigerating cycle and comprising a condenser and a fan associated thereto, a compressor, an evaporator, an expansion valve, and an electronic control system; wherein the expansion valve is non-electronically controlled, with the electronic control system configured to: receive a signal indicating an external ambient temperature (T ext ) outside a vehicle; receive a signal indicating a measured condensation pressure (P meas — fluid ) of a coolant in the condenser; determine a target condensation pressure (P target — fluid ) of the coolant in the condenser based on the external ambient temperature (Text); generate a condenser fan control signal (Sc) based on the measured condensation pressure(Pmeans_fluid) and the target condensation pressure (Ptarget_fluid) of the coolant in the condenser; determine a pressure error (ep) indicative of a difference between the measured condensation pressure (Pmeas˜fluid) and the target condensation pressure (Ptarget_fluid) of the coolant in the condenser; and generate the condenser fan control signal (Sc) based on the pressure error (ep).