GREE                                                          DC Inverter Multi VRF System II Service Manual 
98 
4 Power Distribution of Unit 
4.1 Power distribution of unit 
The control logical relationship among parts inside the electric box of unit is showed by the mongline 
diagram (CAD source file).   
The main loop is showed by bold line (line width: 1mm); the control loop is showed by slim line (line 
width: 0.2mm).   
 
 ˄Bold line is the power line and the slim line is the control line˅ 
4.2 Main electric parts   
It main effect is to eliminate the interference of 
power for protecting unit’s anti-inter
ference 
capability and prevent the interference to other 
electric appliances. 
There are three complemental IGBT tube 
inside the IPM module. They are controlled by 
PWM wave and then bring the pressure of DC 
bus bar
 
to different stator windings of 
compressor at different stage, and then 
generate current on the stator. Meanwhile, 
magnetic field will be generated on the stator 
winding, and push the operation of rotor and 
then drive compressor to operate.