Basic Control; Normal Operation; Compressor Control; Main And Sub Unit's Lev Control - LG multi V PLUS Service Manual

Function

1. Basic control

1.1 Normal operation

Actuator
Compressor
Fan
Main LEV
4 way valve
Subcooling
LEV

1.2 Compressor control

Fuzzy control : Maintain evaporating temperature(Te) on constant state on cooling mode and condensing
temperature(Tc) on constant stage on heating mode by Fuzzy control to ensure the stable system perfor-
mance.

1.3 Main and sub unit's LEV control

(1) Main LEV's fuzzy control
Main LEV operates with fuzzy control rules to keep the evaporator outlet super Heat(Superheat) stable
state during heating mode
Superheat = Tsuction - Tevaporation
Tsuction : temperature at suction pipe sensor(˚C)
Tevaporation : evaporation temperature equivalent to low pressure(˚C)
(2) Sub LEV's fuzzy control
Sub LEV operates with the same rules of main LEV, but the operating range is Limited by main LEV's
current opening rate
- Limited conditions : liquid back control, discharge temperature control etc.
204 Outdoor Unit
Cooling operation
Fuzzy control
Fuzzy control
Full open
Off
Fuzzy control
Heating operation
Fuzzy control
Fuzzy control
Fuzzy control
On
min.
Stop state
stop
stop
After 15min,
min. pulse
After 15min, Off
After 15min,
min. pulse