| 摘要 |
PROBLEM TO BE SOLVED: To increase reliability by rapidly detecting decline in the input voltage of an inverter circuit and stopping the drive of a power switching semiconductor to prevent the destruction due to decline in voltage, when converting the DC power obtained by rectifying an AC power supply into the AC power to drive a motor of a washing machine, etc. SOLUTION: The DC power of a rectifying circuit 3 connected to an AC power supply 1 is converted into the AC power by controlling an inverter circuit 4, by means of a control circuit 6 to drive a motor 5. The control circuit 6 controls the rotation of the motor 5 by means of a rotation control circuit 61 for controlling the rotation of the motor 5, and the input voltage of the inverter circuit 4 is detected by a voltage detector 62. Based on the rate of change of the detected voltage, the output of the inverter circuit 4 is made to stop by a voltage drop detector means 63 for detecting the voltage drop abnormality, and an output inhibiting means 64 to protect the inverter circuit 4 from the voltage drop abnormality. |
