Research Of Millimeter Wave Radar Depth Indicator For Mine

The currently used two kinds of mine hoist depth indicator, vertical depth indicator and disk depth indicator, both acquire the rotating status directly from the principal axis. If the steel wire slides, creeps or tensile deformation in the process of ascension, it will cause deviation between the display position and the actual location of the hoisting container, and the driver is unable to make correct judgment promptly, which may cause accidents and losses. The key to guarantee the safe performance of the hoist is to solve the problem of monitoring the hoist's stroke and speed. The multi-functional backup stroke monitoring system researched in recent years has been improved in safety performance, but its cost is high and equipment is complex. What's more, it failed to solve the drawbacks lying in the existing hoisting system stroke as well as the speed measurement from the root. Therefore, completely changing the former ways of speculating the position of hoisting container, making the accurate measurement of stroke and speed, are keys to solving this problem.According to the actual situation of coal industry and based on the theory of electromagnetic distance measurement, this paper adopts a direct measurement way designing a new Millimeter Wave Radar Depth Indicating System. It will replace the traditional depth indicator, not only realizing precise instruction and the real-time monitor of the hoisting container's position and speed, but also realizing several protection functions like overwinding, speedlimiting and acoustic-optic indicating. The fault records can be classified stored into a special database. Fixing a rangefinder on the derrick stents and installing a reflecting device on the hoisting container, by means of measuring the phase difference produced by modulation wave transmitting roundship between the measuring distance, the distance and speed value will be measured. The measured data by this method not only can avoid the impaction of wire rope sliding, creeping and tensile deformation, but also is real time and accurate, which can avoid the happening of overwind and overspeed. It has been proved by practice that, using this method to suppress the interference can realize accurate and reliable stroke and speed protection. Moreover, the design is simple and easy to use. The following work has been done by the author: Firstly, he analyzed the drawbacks of the existing depth indicator, determined the final solution, and put forward a general design thought of the system; Then, according to the overall design scheme, the compositions, functions and principles of each part have been analyzed, and the whole system's software, hardware as well as the anti-interference performance have been designed; Finally, the author built a system model. Through comparison and analysis of the MATLAB simulation results, from aspects such as measurement accuracy, low cost and reliability, etc. it can be concluded that, the MMW Radar Depth Indicating System, which has been designed in this subject, can both meet the design object of long distance, high accuracy and high stability, and the requirement of low cost and full functions.