To provide an air conditioner that has an improved heating capacity.
An air conditioner includes: an electric motor 8 for driving a blower fan 7 for blowing air to an outdoor heat exchanger 3; an inverter 9 powered by a DC power supply 10 to apply a voltage to the electric motor 8; a shunt resistance 14 connected between the DC power supply 10 and the inverter 9; a voltage holding section 15 adapted to charge with a voltage across the shunt resistance 14 and discharge the charged voltage at a predetermined time constant; and an inverter control section 11 for controlling the voltage output by the inverter 9. The inverter control section 11 detects a value of current flowing through the shunt resistance 14 on the basis of the voltage discharged from the voltage holding section 15, and reduces the frequency of the voltage output from the inverter 9 to the electric motor 8 if the detected current value exceeds a prescribed value or increases the frequency of the voltage output from the inverter 9 to the electric motor 8 if the detected current value falls below the prescribed value, so that a constant current flows.
WO/1994/007188 | SERVO AMPLIFIER AND SERVO SYSTEM |
JPS5869497 | MOTOR CONTROL SYSTEM BY CURRENT PWM INVERTER |
WO/2012/035385 | INVERTER APPARATUS AND INVERTER CONTROL METHOD |
JP2008245397A | 2008-10-09 | |||
JP2006042413A | 2006-02-09 |
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