To provide a motor drive unit which can prevent the abnormal overheating of a rush current suppression resistor by detecting the non-operation of a rush current suppression circuit, and is high in safety.
The motor drive unit includes: the rush current suppression circuit 12 which is connected between positive electrodes of a converter 11 and a smoothing capacitor 13, and in which the rush current suppression resistor 12a and a switch 12b are connected in parallel with each other; a voltage detection circuit 16 connected to both ends of the rush current suppression circuit 12; a control circuit 15 which controls the switching of the switch 12b and the drive of the inverter 14 on the basis of a servo signal; and a logic circuit 17 which inputs the servo signal from the control circuit 15 and an output of the voltage detection circuit 16. The logic circuit 17 outputs an abnormality detection signal to the control circuit 15 from the logical sum of a voltage detected by the voltage detection circuit 16 and a servo-on signal, and the control circuit 15 stops the drive of the inverter 14.
| JPH10201136A | 1998-07-31 | |||
| JP2003174778A | 2003-06-20 | |||
| JP2001320875A | 2001-11-16 |
Hiroki Naito
Daisuke Nagano
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