Research On Control Technology For Earthquake Simulation Test System

In the communications industry, random vibration-based tests must be carried out for seismic test of telecommunications equipment. In this paper, on the background of rebuilding digital control system for BD-YZT vibration table of the earthquake simulation test system, the ability of seismic test is enhanced by improving the frequency characteristics and the accuracy of tracking seismic waves of the earthquake simulation test system so that it can both reduce the damage of telecommunications equipment and improve the reliability during an earthquake.Firstly, time-domain waveform replication (TWR) algorithm is studied in order to achieve high-precision random vibration test in the earthquake simulation test system. The basic steps of the algorithm are analyzed and FRF (frequency response function) H1 estimator is used to estimate the FRF of the system. Then drive spectrum iteration correction based on intelligent control is selected for the correction of drive signals. Main points of implementing the algorithm in the TWR control software are summarized and the flow chart of the algorithm is also given.Secondly, as YD5083—2005 Specification for Seismic Test of Telecommunica- tions Equipment requested, the theory of synthetic seismic wave is studied in order to achieve inversion and synthesis of artificial seismic wave in the digital control TWR software in the earthquake simulation test system. The basic principles of fitting response spectrum using trigonometric series method are analyzed and the mathematical model is also derived. Then some improvements are made on the basis of trigonometric series method to reduce the time of generating artificial seismic wave whose response spectra should converge at the object response spectra in a high precision and quickly.According to the functional requirements of TWR software, a series of function modules of the software are classified for software designing. RCP technology based on Real-Time Windows Target software designing environment is introduced and the real-time simulink module is also designed. The interface of the software whose menus and sub-windows are also simply introduced is designed by GUIDE in Matlab environment. The designed software has functions of generation of a variety of drive signals, iterative processing, display and post-processing.Finally, the vibration control system and servo control system are linked up to test the rebuilded earthquake simulation test system. The results proves that the digital control system can implement the required functions, furthermore the frequency characteristics and the accuracy of tracking seismic waves of the earthquake simulation test system are improved, meeting YD5083—2005 Specification for Seismic Test of Telecommunications Equipment requirements.