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MXZ MICROPROCESSOR CONTROL
3-1. INVERTER SYSTEM CONTROL
3-1-1. Inverter main power supply circuit
POWER BOARD
| NOISE FILTER P. C. BOARD |
| |
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| R64A/R64B | L |
POWER | CT61 | X64 |
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SUPPLY |
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N/F |
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|
PFC
+CB1
CB2
CB3
|
| V |
CT1 | U | MC |
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| |
U |
| W |
IPM |
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|
V |
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|
CT2 |
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|
W |
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Function of main parts
SYMBOL | NAME | FUNCTION | |
IPM | INTELLIGENT POWER MODULE | It supplies | |
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CB1~3 | SMOOTHING CAPACITOR | It stabilizes the DC voltage. | |
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CT1~2 | CURRENT TRANSFORMER | It measures the current of the compressor motor. | |
CT61 | CURRENT TRANSFORMER | It measures the current of the main power supply circuit. | |
L | REACTOR | It rectifies AC, controls its voltage and improves the power factor of | |
PFC | POWER FACTOR CONTROLLER | power supply. | |
R64A, R64B | It restricts rush current with the resistance. | ||
X64 | RELAY | It | |
compressor operates. | |||
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3-1-2. Outline of main power supply circuit
1.At the start of operation
Main power supply circuit is formed when X64 (Relay) is turned ON at compressor startup.
To prevent rush current from running into the circuit when power supply is turned ON, R64A and R64B
2.At normal operation
1 When AC runs into noise filter P.C. board, its external noise is eliminated in the noise filter circuit.
2 After noise being eliminated from AC, it is rectified to DC by L (Reactor) and PFC (Power factor controller). If the operating frequency becomes 25Hz or more, DC voltage rises to 370V.
3 DC voltage, to which has AC been rectified by process 2, is stabilized by CB1~3 (Smoothing capacitor) and supplied to IPM (Intelligent power module).
4 The DC (Bus voltage), which has been stabilized in process 3, is converted to
5 CT1 and CT2 (Current Transformer), which are 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 impre- ssed voltage and frequency with those information.
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