SERVO CONTROL APPARATUS HAVING FUNCTION OF OBTAINING FREQUENCY CHARACTERISTICS OF MACHINE ON LINE

摘要

A servo control apparatus according to the present invention includes a speed command generator; a torque command generator; a speed detector for detecting the speed of a servomotor; a speed control loop including the speed command generator, the torque command generator, and the speed detector; a sinusoidal sweep input unit for performing a sinusoidal sweep on the speed control loop; and a frequency characteristics calculator for estimating the gain and phase of speed control loop input and output signals from the output of the speed control loop when a sinusoidal disturbance is inputted thereto. The frequency characteristics calculator expresses the output of the speed control loop as the Fourier series having an arbitrary number of terms using a disturbance input frequency as a fundamental frequency, and calculates the amplitude and phase of a fundamental component of the Fourier series in order to calculate frequency characteristics on line.

主权项

1. A servo control apparatus that is a control apparatus for a machine tool having a feed axis driven by a servomotor comprising:
a speed command generator for generating a speed command value for the servomotor; a torque command generator for generating a torque command value for the servomotor; a speed detector for detecting the speed of the servomotor; a speed control loop including the speed command generator, the torque command generator, and the speed detector; a sinusoidal sweep input unit for performing a sinusoidal sweep on the speed control loop; and a frequency characteristics calculator for estimating the gain and phase of speed control loop input and output signals from the output of the speed control loop when a sinusoidal disturbance is inputted to the speed control loop of the control device, wherein the frequency characteristics calculator expresses the output of the speed control loop as the Fourier series having an arbitrary number of terms using a disturbance input frequency from the sinusoidal sweep input unit as a fundamental frequency, and calculates the amplitude and phase of a fundamental component of the Fourier series in order to calculate frequency characteristics on line.