Development Of Mine Braking Device Liquid Inertia Simulation Test Bench

Based on the large volume of the mechanical flywheel of the mechanical inertia test bench,when the flywheel rotates at high speed,there is a great potential safety hazard and can not realize the stepless change of inertia.The control mode of the electrical inertia test bench is complex,and the installation accuracy of the flywheel is high.This paper studies and designs the ’liquid inertia ’ test bench combined with the working characteristics of the mine brake device.It is a volume speed control hydraulic system composed of variable displacement pump and quantitative motor,which can realize the simulation of inertia.The control method is simple,the flywheel installation accuracy is low,the volume is small,and the operation is convenient.The main research work of this paper is as follows:(1)Based on the analysis and study of the electric inertia test bench and the mechanical inertia test bench,combined with the advantages of the two,a new simulation method,namely,the hydraulic speed control system composed of variable pump and quantitative motor,is adopted to simulate the rotational inertia.At the same time,it provides a reliable control method for the experimental platform,that is,using PID and backstepping control strategy to improve the control accuracy of the system.(2)According to the working condition requirements of mine braking device,the performance index of the test bench is analyzed and determined,and the overall scheme of the test bench is formulated.The schematic diagram o f the hydraulic system was designed,and the calculation and selection of the key components were carried out.AMESim simulation software was used for modeling and simulation of the hydraulic system of the experimental platform.The correctness of the component selection of the hydraulic system was verified by comparing the data obtained from the simulation analysis with the data from the theoretical calculation.(3)The data acquisition system is designed.Cortex-A7 is used as the microcontroller to design the circuit to realize the acquisition function,including temperature acquisition circuit,displacement acquisition circuit,speed and torque acquisition circuit.Establishment of Linux embedded system for the platform acquisition system,including building NFS server,kernel clipping,establishing root file system,transplanting bootloader,and writing core driver for the platform development board.(4)The human-computer interaction interface is designed by QT platform.The data of spindle speed,braking torque,friction plate temperature,noise and system pressure collected at the back end can be displayed on LCD screen in the form of curve.(5)Experimental verification.The performance test of the braking device,the wear life of the friction pair of the brake,the noise of the brake,the thermal recession and the recovery of the brake are verified by the experimental platform.The data acquisition and curve drawing of the braking torque,the spindle speed,the wear of the friction plate and the noise are realized,and the expected requirements are achieved.