Research On Model And Simulation And Test Of High-speed Test Bench Of Mechanical Transmission

As a new and essentialitem of the national automotive industry standards QC/T568.1-2011,the purpose of the high-speed bench test of mechanical transmissions is to verify the reliability,stability and durability of the MT under the high-speed,huge-load and long-time condition.In the actual high-speed test,the test bench can not meet the requirements of high-speed test because of the lack of control accuracy of the test system.In order to solve this problem by adding speed/torque PI controller,a high-speed test and simulation system of mechanical transmission are built based on MATLAB/SIMULINK simulation platform.First of all,the type of test drive motor is determined as a three-phase induction motorthrough the comparative analysis.Based on the mathematical model of three-phase induction motor,the characteristics of strong coupling,nonlinear,highorder are analyzed.In order to decouple the mathematical model,the mathematical model of vector control system with torque inner loop is established by using the method of coordinate transformation in the synchronous rotating coordinate system.Based on the classical PID control theory,the type of speed and torque regulator is determined as a PI regulator.Secondly,based on the established mathematical model of the driving motor,the simulation system of mechanical transmission high-speed test bench is built with the SIMULINK module library by using Maltlab as the developing platform.Based on this simulation system,the effects of various coefficients of PI regulators on high speed test are studied.According to the requirement of high-speed test,a high-speed simulation test with PI regulators is carried out,which verifies the rationality of the designed PI regulators.Thirdly,based on the characteristics of the high-speed test,by comparing the different types of test bench,the design scheme is determined as a common DC bus energy feedback electric closed test bench.The reasonable parameters of the drive motor are determined by using the software of SIZER motor.The selection of measuring and controlling hardware such as torque sensor,data acquisition card,host computer and lower computer communication mode is selected,and the mechanical system and control system of the test bench are constructed.Actual high-speed test results show that the control accuracy of the MT high-speed test bench with PI regulator is improved significantly,which fully meet the actual high-speed test requirements.As a result,the problem of the lack of accuracy is solved.The economy,efficiency,accuracy and reliability of the simulation system are high,which provides a new and reliable technical means for the development and design of the test bench.