| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor control unit avoiding destruction of an element due to excessive current generated in power restoration of an AC power supply and to provide an air conditioner with the motor control unit. <P>SOLUTION: An instantaneous value detecting means 15 detecting an instantaneous value of the AC power supply 1 is arranged in a capacitor input-type power supply part, and it is connected to an A/D conversion terminal of a microcomputer 13. The microcomputer 13 detects the instantaneous value of the AC power supply at a sufficiently shorter interval than a period of the AC power supply from an output signal of the instantaneous value detecting means 15, and repetitively obtains maximum values of the AC power supply based on the detected latest, previous, and second previous instantaneous values. The obtained maximum value of the AC power supply is repeatedly compared with a determination value which is previously set. When the obtained maximum value of the AC power supply is smaller than the determination value for a predetermined time, it is determined that power interruption or voltage drop occurs, and a stop signal of the power supply part and a motor driving part is output. <P>COPYRIGHT: (C)2009,JPO&INPIT |
