| 摘要 |
PROBLEM TO BE SOLVED: To obtain a fault detector for a servo control system for detecting a failure of a current sensor easily. SOLUTION: The detector is provided with a PWM inverter 25 which applies voltage and frequency which are variable to a servomotor 10, an encoder 12 for detecting an angle by which the rotor of the servomotor 10 rotates, a command means which generates a limited voltage command to the PWM inverter 25, current sensors 27v, 27w for detecting individual currents Iv, Iw which flow by operating the PWM inverter 25 on the basis of the voltage command from the command means and applying voltages Vu, Vv, Vw to the servomotor 10, and a judging means which finds Iv×Vw and Iw×Vv, judges whether the difference between Iv×Vw and Iw×Vv is within a specified value, and generates an abnormality signal when the difference exceeds the specified value. |
