Research On Load Sensitive Technology For Height-adjust Hydraulic System Of Shearer

Recently,more and more attention has been paid to the development of the coal industry by the government.As an essential part of underground mining,shearer has the advantages of high productivity,reducing major accident and improving the working condition.As a key part of shearer,the performance of the hydraulic system has a great influence on the efficiency and the raw coal quality of coal mining.Therefore,it is significant to study the hydraulic system of shearer.Currently,quantitative pump hydraulic system is widely used in shearer,However,for the big relief and throttling loss in quantitative pump system,it has low system efficiency.In order to overcome the defect in quantitative pump hydraulic system,the load sensitive technique with high efficiency is adopted.The hydraulic system with load sensitive variable pump for coal cylinder height adjustment system is put forward.The main work is as follows:First,the main reasons of the high energy consumption and low efficiency in coal cylinder height adjustment hydraulic system is clear.Aiming at the disadvantage of quantitative pump hydraulic system,the load sensitive variable pump for coal cylinder height adjustment system is put forward.Secondly,on the basis of the detailed analysis of the working principle of the load sensitive variable pump hydraulic system,the modeling of quantitative pump and load sensitive variable pump hydraulic system is finished by the simulation software Matlab/Simhydraulics.And the analysis of its stability is carried out.Then,based on the consistent dynamic performance of shearer,the comparative analysis and simulation study on the load sensitive variable displacement pump hydraulic system and fixed displacement pump hydraulic system were finished.The results showed that the efficiency on the load sensitive variable pump hydraulic system is much higher than the fixed displacement pump hydraulic system.Then,according to the research objective,the simplified model of shearer mechanism is established in Matlab/Simmechanics,and a joint simulation model of shearer and hydraulic system of the load sensitive variable pump in Matlab/Simulink environment is established.Finally,on the basis of the combined simulation model,PID control strategy is put forward to the position height control hydraulic system(the displacement of the piston rod)and the traction speed.Under the condition of mutations,through the joint simulation analysis of PID controlled shearer,we can get the data of each component in the joint simulation model of shearer.In summary,the load sensitive variable pump hydraulic system proposed in this paper can effectively improve the efficiency of the system,solve the disadvantage of low efficiency of quantitative pump hydraulic system;through the curve of each component in the co-simulation PID controlled shearer model under the mutation condition laid a foundation of the further research on shearer characteristics.