LG CT18F NQ0 User Manual

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All rights reserved. Only training and service purposes.
Part 3 Basic Control
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.
1. Normal operation
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.
2. Compressor control
Cooling and heating load
System capacity
Linear control
Inverter linear control as cooling and heating load increasing
Actuator Cooling operation Heating operation Stop state
Compressor Fuzzy control Fuzzy control Stop
Fan Fuzzy control Fuzzy control Stop
EEV Discharge Temp. Control Discharge Temp. Control Min. Pulse
EEV operates with fuzzy control rules to keep the target temperature of discharge pipe.
＊Cooling mode
* Cooling / Heating mode
The target temperature of discharge pipe :
• T
d
: Theoretical discharge temperature
• T
1
: T
e
(current evaporating temperature) + T
SSH
(Suction Superheating temperature)
• P
high
: Absolute High pressure (kPa)
• P
low
: Absolute low pressure (kPa)
3. EEV( Electronic Expansion Valve) control
n
n
low
high
d
P
P
TT
)1(
1
=

LG CT18F NQ0 Specifications

General

Brand	LG
Model	CT18F NQ0
Category	Air Conditioner
Language	English