Research On Embedded Electronic Control Of Constant Decelerating Braking System In Mine Hoists

Constant deceleration brake takes constant acceleration as a controlled object. Under various conditions, it can makes the hoist in accordance with the given safety braking deceleration values. It not only improves the braking performance, but also effectively prevents the occurrence of the friction hoist rope accident. That’s why it is an ideal braking method for mine hoist. But the traditional control system takes PLC as the core controller, in which the sequential execution mode and the low frequency are more and more difficult to meet the requirements of constant deceleration system for real-time. Under the integration of mechanical, electrical and hydraulic system, constant deceleration brake is more complex, so the traditional PID control is difficult to achieve high efficiency. Therefore, the study of high real-time, high-precision constant deceleration braking control systems has important significance.The topic takes hydraulic conversion device as a controlled object, which can realize the switch of constant torque and constant deceleration. It also studies and designs the control system of constant deceleration braking based on embedded system. Firstly, according to the controlled object and conditions demand, this paper analyzes the system principle and puts forward the hardware scheme of electric control system. Hardware circuit adopts bipolar plate splicing scheme. It is divided into core board and peripheral circuit board for system debugging. The former contains the microprocessor and the required circuit while the latter contains oil pressure input circuit, overflow valve output circuit. That is to say, the latter is a collection of input and output circuits. In order to improve the reliability of the hardware circuit board, the research of electromagnetic compatibility and design of PCB board is also carried out in this paper.Secondly, combining with hardware system and the control principle of constant deceleration braking, this paper gives a multitasking software systems project based on embedded and real time operating system. The software systems includes two parts- multitask of constant speed reduction and control algorithm. μC/OS-II can do with multitask at the same time, having higher real-time performance.Fuzzy neural network is adopted for control algorithm in this paper. It constructs a neural network based on T-S fuzzy model and offline training. These results can be directly applied. Moreover, this paper introduces the Calman filter and designs the Calman filter to improve the processing precision of velocity feedback.Finally, based on the above research, this paper carries out the integrated simulation and experiment of the electric control system of constant deceleration. It collects the encoder data processes the acceleration value through the Calman filter and traditional velocity measurement method. The experimental results show that the accuracy of Calman filter is better. Then, based on fuzzy neural network control algorithm,the paper carries out the integrated simulation of constant deceleration braking system. The simulation results fully meet various conditions. In the end, it builds experimental platform and tests in a laboratory to verify the feasibility of the electronic control system.