Controlling On Test Bed Of Hydrostatic Transmission

Hydrostatic Transmission (HST) is a hydraulic transmission driver, it collects the bidirectional variable displacement pump, the constant displacement motor, the gear pump and the control valve in a body. HST widely applies to engineering vehicles and farm machinery. This thesis developed a controlling test bed of HST, developed testing and controlling system software based on virtual instrument technology, and carried on the HST experiment of control in the test bed.The thesis introduced research progress of hydrostatic transmission technology and virtual instrument. The thesis introduced the operating principle, the basic structure of HST in detail and the performance of engine, proposed the design plan of HST controlling test bed; designed the machine part of test bed, including choice of power device, loading device and torque and rotating speed sensor, design or choice of drive shaft, shaft coupling, bearing, bearing pedestal and so on. The test bed has overcome inconvenience bring by especial configuration of HST in mechanical structure arrangement, Conclusions are made that the controlling test bed of HST play a key role in engineering vehicles and farm machinery.The measurement and control system of test bed is composed by hardware part and the software part. The hardware part included the choice and calibration of sensor, the choice of data acquisition card. In the software design part, the author developed measurement and control system software with the LabVIEW language based on the virtual instrument technology, designed the program of data acquisition and control system. This software has friendly interface together and powerful functions, can carry out data display, the automatic recording, automated analysis and so on, and has improved the reliability and veracity of data.Finally, the thesis carried on the HST controlling experiment using the test bed. The result shows that: the controlling of HST is feasible based on virtual instrument in computer. It has the strongpoint of more reliable date and using less time thus enhances the efficiency of produce.