APPARATUS PREVENTING THE VIBRATION AT FINISHING STANDS IN STRIP MILL, USING THE ADAPTIVE CONTROL ALGORITHM

摘要

PURPOSE: To provide a vibration suppressing apparatus for solving problems such as defect of thickness quality and damage of rolling rolls according to generation of chattering phenomenon by using an adaptive control algorithm for suppressing vibration of a finish rolling mill. CONSTITUTION: The apparatus comprises a vibration sensing processing part comprising a vibration sensor(4-1) attached to a stand housing of the finish rolling mill to convert the measured vibration into a voltage signal by measuring vibration according to time, an amplifier(4-2) and a low pass filter(4-3) for removing unnecessary high frequency noise by amplifying the measured signal, a sampler(4-4) for sampling an analog signal filtered by the low pass filter at certain time intervals, an analog to digital converter(4-5) for converting the sampled signal into digital signal, a vibration generation determination circuit(4-6) for converting a signal passing through the analog to digital converter into a root mean square value, a FFT operation circuit(4-9) for performing a FFT(fast fourier transform) operation for calculating the measured vibration value according to time in a vibration frequency value, and an adaptive feedforward cancellation controller(4-10) for performing operation using an adaptive control algorithm by receiving vibration frequency information transmitted from the FFT operation circuit and vibration magnitude transmitted from the analog to digital converter; and a rolling mill control part comprising an AGC(automatic gauge controller)(4-11) signally connected to the adaptive feedforward cancellation controller, and a hydraulic cylinder control valve(4-12) connected to the AGC to operate hydraulic cylinders(4-15a,4-15b) installed at both sides of shaft of an upper back up roll(4-16a) of the finish rolling mill.