| 摘要 |
PROBLEM TO BE SOLVED: To provide a failure discrimination device of a 3 phase brushless motor capable of discriminating failures including disconnection, earth fault, power line fault in respective phases of motor wiring, with no current limiting circuit required.SOLUTION: A failure discrimination device for a 3 phase brushless motor includes three motor terminals connected to coils of respective phases of a 3 phase brushless motor, a motor drive circuit containing a switching element for controlling operation of the 3 phase brushless motor and connected to a positive terminal and a negative terminal of a DC power source and the three motor terminals, a voltage monitoring signal line which is connected to at least a motor terminal of one phase among the three motor terminals for voltage division, to be connected to a monitoring device, a pull-down resistor provided between the negative terminal of the DC power source and the motor terminal, and a pull-up resistor provided between the positive terminal of the DC power source and the motor terminal. A part of three motor terminals is connected at least to the pull-down resistor, and remaining parts are connected to at least the pull-up resistor. The monitoring device discriminates failure of a coil based on a voltage of the voltage monitoring signal line when all the switching elements are turned off. |
