1. Normal operation
Basic principle is to control the rpm of the motor by changing the working frequency of the compressor.
Three phase voltage is supplied to the motor and the time for which the voltage will supplied is controlled by IPM
(intelligent power module).
Switching speed of IPM defines the variable frequency input to the motor.
Actuator
Compressor
Fan
EEV
2. Compressor control
Fuzzy control : Maintain evaporating temperature (Te) to be constant on cooling mode and constant condensing
temperature (Tc) on heating mode by fuzzy control to ensure the stable system performance.
3. EEV( Electronic Expansion Valve) control
EEV operates with fuzzy control rules to keep The degree of superheat (2~3℃) or the target temperature of discharge pipe.
*Cooling mode
The degree of superheat = Tsuction – Tevaporator
Tsuction : temperature at suction pipe sensor(℃)
Tevaporator : evaporation temperature (℃)
*Heating mode
the target temperature of discharge pipe = T condenser + α
T condenser : condenser temperature (℃)
Cooling operation
Fuzzy control
Fuzzy control
Super heating
fuzzy control
Inverter linear control as cooling and heating load increasing
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Heating operation
Fuzzy control
Fuzzy control
Discharge Temp. Control
Linear control
Cooling and heating load
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Stop state
Stop
Stop
Min. Pulse