4.Intelligent power module
IPM consists of the following components
· IGBT (x6) | : Converts DC waveform to |
· Drive Circuit | : Drives transistors. |
· Protection circuit | : Protects transistors from overcurrent. |
Since the above components are all integrated in IPM, IPM 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 capacitors placed on the POWER P.C. board, eliminates electri- cal noise of AC power that is supplied to main power supply circuit. And this circuit prevents the electrical noise generated in the inverter circuit from leaking out.
*CMC COILS; Common mode choke coils
MUZ-A24 MUY-A24 MUZ-D MUY-D
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 are 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 being eliminated from AC, it is rectified to DC by REACTOR and PFC. 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 IPM.
The DC (Bus voltage), which has been stabilized in process 
, is converted to
COMPRESSOR.
CURRENT TRANSFORMER, which is placed in the power supply circuit to COMPRESSOR, are used to measure the value of phase current and locate the polar direction of rotor with algorithm. PWM (Pulse width modulation) controls im- pressed voltage and frequency with those information.
3.Power factor improvement
Booster coil reactor and power factor controller 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. PFC and reactor stabi- lize the voltage of DC supplied to inverter circuit and make its waveform smooth.
4.Power transistor module
IPM consists of the following components.
· Power Transistors (x6) | : Converts DC waveform to |
· Drive Circuit | : Drives transistors. |
· Protection circuit | : Protects transistors from over current. |
Since the above components are all integrated in IPM, IPM has a merit that can get the control circuit simplified and miniatur- ized.
5.Elimination of electrical noise
NOISE FILTER CIRCUIT, which is formed by *CMC COILS and capacitors placed on the noise filter P.C. board, eliminates electrical noise of AC power that is supplied to main power supply circuit. In short, common mode noise is absorbed in this circuit.
Moreover, normal mode noise is absorbed in another NOISE FILTER CIRCUIT which is formed by *NMC COILS and capaci- tors.
Both NOISE FILTER CIRCUIT exists for preventing 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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