Acceleration Harmonic Estimation for Hydraulic Servo Shaking Table Based on Multi-Innovation Stochastic Gradient Algorithm

Abstract

As one of the critical test equipment, hydraulic servo shaking table is widely used in shaking environment simulation of structural components and systems. However, inherent nonlinear factors of a hydraulic servo shaking table can cause amplitude attenuation and phase lag when corresponding to a sinusoidal acceleration signal, which leads to serious harmonic distortion. In order to improve waveform reproduction performance of sinusoidal signals, the amplitude and phase of harmonic should be estimated accurately. In this paper, the multi-innovation stochastic gradient (MISG) algorithm is presented for dynamically estimating the harmonic information. Simulation and experiment results demonstrate that the proposed algorithm has high estimation precision and good convergence performance.