Research On Electro-hydraulic Servo Synchronous System Based On LabVIEW

With the rapid development of modern machinery processing, aerospace, waterconservancy and hydropower and construction etc.There are more and morerequirements for synchronous precision of multi-cylinder synchronous system.Leakage, processing accuracy and performance gap of controlling components willlead to asynchronous of multi-cylinder system. If we can’t take effective measures toovercome this synchronous error, the controlling system will not work properly. Soit is necessary to design correctly hydraulic synchronous controlling system basedon the theoretical analysis.Firstly, the paper reviewed the research status of the hydraulic synchronous andthe virtual instrument technology, the components, characteristic and application ofsystem, and introduced the development of the synchronization control strategybased on lots of correlative literatures and reference materials at home and abroad.The electric-hydraulic servo valve is widely used in hydraulic sync systembecause of its high frequency response and high precision. Sync system with twocylinders is chosen as the research object and the sync system with electro-hydraulicservo valve is designed. The composition and controlling strategy of the system arestudied. Mathematical model of the system is built with both linear and nonlinearmethods and the simulation model is created by Control and Simulation kid ofLabVIEW software. The results of two kinds modeling method are compared andanalyzed in the paper. It is proved that nonlinear modeling method can reflect thereal dynamic behavior of the system.The synchronous control principles of the same way and the master-slave wayare detailed analyzed, Simulation model of two kind of hydraulic synchronoussystem are created respectively in nonlinear ways The method of binarycompensation is adapted in the simulation according to the character of the system.And the response of the system is simulated with step signal, slope signals anddifferent frequency sine signal. The sync precision and dynamic character of thesystem are summarized theoretically. PID controller is designed on the method ofbinary compensation in order to improve higher sync precision. For synchronousalgorithm can’t improve the dynamic performance of system, PID controller isdesigned for each system based on the synchronous method of dichotomy. Theresults of simulation showed that the method not only increases the synchronousaccuracy but also improves the dynamic behavior of the system. In order to verify the correctness of the result of simulation, the pump station,actuating unit, measurement system and control system are designed, and theplatform for the test of hydraulic synchronous control system are built. Themeasuring and controlling program which is built by LabVIEW realized thefunctions of real-time monitoring, process control, post-processing and etc. Thecontrol strategy is verified by experiments. It is proved the accuracy of thesimulation results. The test refer to the condition of different amplitudes, differentload and different oil pressure are carried out in the final part of the paper. Theresults show the correctness of theoretical analysis. It is quite significant fordesigning turbine governor; the control system of ring gate and the control system ofneedle in impulse turbine. And it is important for practical engineering applicationand the further study.