Resonant frequency online identification and suppression method for servo system

Abstract

The invention discloses a resonant frequency online identification and suppression method for a servo system. The resonant frequency online identification and suppression method comprises the following steps: inputting a rotating speed deviation and setting an initial frequency; obtaining a transfer function according to the structure of the second-order generalized integrator, and calculating an output signal; calculating a frequency error signal, inputting the frequency error signal into a low-pass filter of the frequency-locked loop, and multiplying the output of the low-pass filter by a proportional controller; multiplying the output of the proportional controller by a gain self-adjusting unit, inputting an output value into an integrator, summing the output frequency of the integrator and a set initial frequency to obtain an estimated resonant frequency, and judging whether convergence time is reached or not; and if the convergence time is reached, inputting the estimated resonant frequency into the notch filter, and setting the estimated resonant frequency as a notch frequency point of the notch filter, thereby realizing resonance suppression. According to the method, the resonance of the servo system can be accurately identified and suppressed, especially under the condition that the rotating speed vibration frequency is relatively high, so that the performance of the servo system is improved.

Description

technical field [0001] The invention belongs to the technical field of servo drive control, and in particular relates to an on-line identification and suppression method for resonance frequency of a servo system. Background technique [0002] Commonly used mechanical resonance frequency identification methods are mainly divided into two categories: off-line and on-line. The offline identification method is carried out when the servo system is in an abnormal working state. Generally, an additional excitation signal is required to draw a Bode diagram according to the speed response of the system, and then directly observe the frequency and amplitude of the resonance peak through the Bode diagram. characteristic. Although this method can accurately obtain the resonance characteristics of the system, in some special occasions, the servo system is often not allowed to be in abnormal working conditions, so it has certain limitations. The online identification method refers to th...

AI Technical Summary

Problems solved by technology

However, there are still problems that the identification accuracy is low after digital implementation and the identification convergence time is affected by the characteristics of the frequency and amplitude of the input signal.

Images