| 摘要 |
A gyroscope motor control system has a phase-locked loop circuit and an antihunting circuit. The phase-locked loop circuit has a voltage-controlled oscillator which produces the drive signal for the motor. The frequency of the oscillator is controlled by the output of a phase discriminator which is in turn dependent on the difference in phase between a reference frequency and a feedback signal from the motor drive signal. A capacitive pick-off senses the speed of rotation of the gyroscope inertia wheel and a signal in response to this speed is supplied to a directional phase discriminator together with the feedback signal. The output of the discriminator varies with change in phase difference between its two inputs, and is supplied via a switching transistor to the input of the oscillator to effect minor variations in its frequency such as to reduce fluctuations in motor speed. The transistor is held off until there is substantial synchronism with the motor drive signal and the inertia wheel speed. |
