Method of and apparatus for detecting anomalous running of motor
AssigneeFanuc Corporation
InventorKaname Matsumoto
Life of this patent
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Abstract
A method of and an apparatus for quickly detecting an anomalous running of a motor. In a motor control system which executes a speed loop process by feeding back a speed of the motor and also a position loop process by feeding back a position of a mechanical system driven by the motor, a speed feedback value of the motor is compared with a reference value, and a direction of the speed feedback value with the direction of a position feedback value. It is discriminated that the motor is running anomalously, when an absolute value of the speed feedback value is larger than the reference value and the sign of the speed feedback value is reverse to the sign of the position feedback value.
Claims6
A method of detecting an anomalous running of a motor in a motor control system in which a position loop process is executed by feeding back a position of a mechanical system driven by the motor and a speed loop process is executed by feeding back a speed of the motor, said method comprising the steps of:
- (a) comparing a speed feedback value of the motor with a reference value and discriminating whether or not said speed feedback value is larger than the reference value;
- (b) comparing a sign of said speed feedback value with a sign of said position feedback value and discriminating whether or not the sign of said speed feedback value is identical with the sign of the position feedback value;
- and
- (c) detecting the anomalous running of the motor based on the result of discrimination in said step (a) and the result of discrimination in said step (b).
An apparatus for detecting an anomalous running of a motor in a motor control system in which a position loop process is executed by feeding back a position of a mechanical system driven by the motor and a speed loop process is executed by feeding back a speed of the motor, said apparatus comprising:
- a first discriminator for comparing a speed feedback value of the motor with a reference value and discriminating whether or not said speed feedback value is larger than said reference value;
- a second discriminator for comparing a sign of said speed feedback value with a sign of said position feedback value and discriminating whether or not the sign of said speed feedback value is identical with the sign of said position feedback value;
- and
- an anomalous running detector for outputting an anomalous running detection signal when said feedback value is larger than said reference value and the sign of said speed feedback value is opposite to the sign of said position feedback value.
Dependencies are inferred from the claim text.