Normal Operation; Compressor Control; Eev( Electronic Expansion Valve) Control - LG AMNW07GDBB0 Service Manual

Part 3. Basic Control

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 temper-
ature (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 (about 2~3℃) at the evaporator outlet status.
The degree of superheat = Tsuction – Tevaporation
Tsuction : temperature at suction pipe sensor(℃)
Tevaporation : evaporation temperature (℃)
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Cooling operation
Fuzzy control
Fuzzy control
Super heating Super heating & Sub cooling
fuzzy control
Inverter linear control as cooling and heating load increasing
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Heating operation
Fuzzy control
Fuzzy control
fuzzy control
Linear control
Cooling and heating load
Stop state
Stop
Stop
Min. Pulse
LGE Internal Use Only