| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve safety and reliability in driving an electric motor by detecting the revolution speed of the motor by a plurality of a revolutions- detecting means, and, if an abnormality occurs to one of the revolutions- detecting means, by detecting the revolutions by the other means, in a motor driving device which drives the motor with an inverter circuit. <P>SOLUTION: DC power of a rectifier circuit 2 connected to an AC power source 1 is converted into AC power by the inverter circuit 3 to drive the motor 4. A rotor-position-detecting means 5 detects the position of the rotor of the motor, a counter electromotive force detecting means 7 does the revolutions of the motor, and a controlling means 6 controls the inverter circuit 3. The control means 6 controls the drive of the motor 4 using the rotor-position- detecting means 5 and the counter electromotive force detecting means 7. <P>COPYRIGHT: (C)2003,JPO |
