Research On Hydraulic Speed Control System Of Boom-type Roadheader’s Cutting Mechanism

Nowdays, coal industry are in a high speed developing in our country, so the ability requirements of boom-type roadheader to excavate the coal crag tunnel is become high ang high. Due to the coal crag tunne rock hardness distribution is uneven, its lead to excavete harder. And invalid loss will increase duing the process. It’s also will increase the workers, control difficulty and increase the accuracy. All of above put forward higher requirements to load feedback speed regulation of boom-type roadheader.The model for this article is boom-type roadheader of EBZ132. In the course of the study in parameters of mainworking mechanism of boom-type roadheader, combine with the sizes of laneway section, establish the mathematic model. Through the traditional methods of displacement measuring and control of hydraulic cylinder, leads to the application of numerical hydraulic cylinder, and use it to control displacement of working hydraulic cylinder of boom-type roadheader. According to the special conditions that coal and rock usually exist together in same section of laneway proposed the program that based on the working conditions to adjustment the feed rate of horizontal and lift cylinder, then control the speed of the cantilever oscillation.and the rated power of cutting motor can be maintained constant.By through comparing the advantages and disadvantages of traditional PID control and fuzzy control, and then combining the characteristics of both, the fuzzy PID control scheme was put foewarded. This scheme can achieve the effect of parameters online self-tuning, then through the stability boundary method and some empirical formula to estimate the initial parameters determined. The basic control idea:when cutting the coal with smaller hardness, then need the high feeding velocity and low feeding force, when cutting the coal or combination of coal and rock with high hardness, then need the low feeding velocity and high feeding force.Simulation of the model was done with Matlab, to study the characteristics of its dynamic and steady-state, and analysis of the feasibility. Results show that the system with the fuzzy PID control can enhance the response speed and the work efficiency, and reduce the power loss of the machine, as well as good control characteristics, and increasing the ability of the boom-type roadheader to adapt to the load changes and complex conditions,and proves the theory support and the basis for the furture improve boom-type roadheader’s load feedback speed regulation technology.