Compressor - LG Single "A" Service Manual

Part 3 Control logic

1. Compressor

1.1 Basic principle
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.
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
120 f
RPM =
P
IPM (Inverter)
EMF
U V W X Y Z
U
V
MCU
W
(16Bits)
RPM ¡ Revolutions/Minute
¡
F Frequency
¡
P Number of poles
BLDC Motor
Position
Detect
Circuit
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LGE Internal Use Only