Application Research Of Hydraulic Soft Braking System Of Downward Belt Conveyor

In recent years, with the increase of cool mining depth and the improvement of deep coal mining equipment technology, the big dip downward belt conveyor gradually has been being applied to coal transportation system and playing a vital role. For large angle downward belt conveyor, when the decline of its component material transport is larger than the running resistance of conveyor, the drive motor is in power feedback operation state, outside brake torque must be applied to ensure the conveyor normal parking, and the larger volume, the greater the inclination, the longer the distance of the under transport sending machine is, the larger braking torque will be required. Therefore, the performance of the brake system has a direct bearing on the reliable operation of the downward belt conveyor safe.In this paper, based on the research of the downward belt conveyor running characteristics and special requirements of the braking system, the composition and working principle of the hydraulic soft-brake system is analyzed in detail; and the analyses calculation of the mechanical model of belt conveyor is made in the braking process, and the heat in the process of braking control and sliding failure are analyzed in theory. Then a theoretical basis for the industrial application of hydraulic soft braking system is proved.By using AMESim simulation software, the hydraulic soft braking system of key hydraulic components (electromagnetic proportional speed control valve, reversing valve cartridge type, braking variable pump) and the dynamic characteristics of the system is simulated and analyzed. The simulation results and the actual operating conditions are in line with the high level, which reveals the hydraulic dynamic operation law of soft braking system. Optimum design of the system and provides important basis for industrial use.The PID controller, based on the fuzzy self-tuning is designed to achieve control of the soft downward belt conveyor hydraulic braking system. The operating speed and the speed variation are selected as the input language of the fuzzy controller. The retardation of the conveyor is used as target control. The fuzzy theory is adapted to establish the rule of the controller. In order to achieve precise control of downward belt conveyor braking deceleration, the control program is designed for different working conditions.Based on the above research, according to different operation condition of hydraulic soft braking system and dynamic characteristics, the laboratory simulation test system is designed, and the principle and steps of the experiment is introduced. The different working conditions of the hydraulic soft braking system, such as the normal braking, speed control of motor speed brake, frequent brake different operating conditions are simulated. And the pressure, the torque, and the oil temperature of the braking system are detected in real time. The results show that the hydraulic brake system with the advantages of the intelligent control, quick response and no greater impact has a good braking effect, which can satisfy the braking performance requirements of the different working conditions of the downward belt conveyor.