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4. Intelligent power module
INTELLIGENT POWER MODULE consists of the following components
· IGBT (x6): Converts DC waveform to 3-phase AC waveform and outputs it.
· Drive Circuit: Drives transistors.
· Protection circuit: Protects transistors from overcurrent.
Since the above components are all integrated in INTELLIGENT POWER MODULE, INTELLIGENT POWER MODULE has
a merit to make the control circuit simplify and miniaturize.
5. Elimination of electrical noise
NOISE FILTER CIRCUIT, which is formed by *CMC COILS and capacitors placed on the POWER P.C. board, eliminates
electrical noise of AC power that is supplied to main power supply circuit. This circuit also prevents the electrical noise gen-
erated in the inverter circuit from leaking out.
*CMC COILS: Common mode choke coils
MUZ-A24 MUY-A24 MUZ-D MUY-D MUZ-FE18 MUZ-GA MUY-GA MUZ-GE24 MUY-GE24
1. At the start of operation
Main power supply circuit is formed when RELAY is turned ON at COMPRESSOR startup.
To prevent rush current from running into the circuit when power supply is turned ON, RESISTOR is placed in sub circuit.
2. At normal operation
When AC runs into noise filter P.C. board, its external noise is eliminated in NOISE FILTER CIRCUIT.
After noise is eliminated from AC, it is rectified to DC by REACTOR and POWER FACTOR CORRECTION MODULE. If the
operating frequency becomes 25 Hz or more, DC voltage rises to 370 V.
DC voltage, to which has AC been rectified by process , is stabilized by SMOOTHING CAPACITOR and supplied to IN-
TELLIGENT POWER MODULE.
The DC (Bus voltage), which has been stabilized in process , is converted to 3-phase AC by INTELLIGENT POWER
MODULE and supplied to COMPRESSOR.
CURRENT TRANSFORMER, which is placed in the power supply circuit to COMPRESSOR, is used to measure the value
of phase current and locate the polar direction of rotor with algorithm. PWM (Pulse width modulation) controls impressed
voltage and frequency with those pieces of information.
3. Power factor improvement
Booster coil reactor and POWER FACTOR CORRECTION MODULE rectify AC to DC and control its voltage.
In the motor drive system of sine wave control, power factor can be improved by reducing harmonics. POWER FACTOR
CORRECTION MODULE and reactor stabilize the voltage of DC supplied to inverter circuit and make its waveform smooth.
4. Intelligent power module
INTELLIGENT POWER MODULE consists of the following components.
· IGBT (x6): Converts DC waveform to 3-phase AC waveform and outputs it.
· Drive Circuit: Drives transistors.
· Protection circuit: Protects transistors from over current.
Since the above components are all integrated in INTELLIGENT POWER MODULE, INTELLIGENT POWER MODULE has a
merit to make the control circuit simplified and miniaturized.
5. Elimination of electrical noise
NOISE FILTER CIRCUIT, which is formed by *CMC COILS, *NMC COILS and capacitors placed on the POWER P.C. board,
eliminates electrical noise of AC power that is supplied to main power supply circuit. This circuit also prevents the electrical
noise generated in the inverter circuit from leaking out.
*CMC COILS: Common mode choke coils
*NMC COILS: Normal mode choke coils
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