Research On Automatic Height Adjustment Control Algorithm Of Shearer Cutting Drum

Shearer is the core equipment to realize the reliability of coal mining system,safety and efficiency of coal production.At present,in the "three machine linkage" technology of fully mechanized mining face,the scraper conveyor and hydraulic support have achieved automatic linkage,but the shearer has not achieved the goal of automatic control.Among them,the automatic height adjustment of shearer drum and its related technology are the key bottleneck technology to realize shearer automation.Therefore,after combining the research status at home and abroad,in order to realize the automatic height adjustment of the drum of electric traction shearer,the automatic height adjustment control method of shearer drum based on memory cutting is proposed.The technologies such as coal and rock cutting state identification,height adjustment control strategy and cutting risk coefficient in the automatic height adjustment system of shearer are studied respectively.The main contents are as follows:(1)To address the problem that individual sensors cannot accurately reflect the cutting state of the drum in a complex underground operating environment,a joint EEMD-wavelet packet method is proposed to denoise and decompose the cut-off information collected by multiple sensors and to extract features,and a PCA algorithm is used to reduce the dimensionality of the feature vector,and finally an optimized Dropout-LSTM neural network is used to identify and learn the feature values that can characterize the cutting state.Finally,the optimized Dropout-LSTM neural network is used to identify and learn the feature values that can characterize the cutting state,so that the shearer control system can accurately and effectively identify the coal rock cutting state to provide technical support for automatic shearer height control.(2)In order to improve the accuracy and speed of the coal miner drum height adjustment system in the process of height adjustment,a mathematical model of the coal miner height adjustment hydraulic system is established to obtain the transfer function between the input signal and the hydraulic cylinder,and a PID control strategy based on the improved firefly algorithm is designed for the timevarying nonlinearity of the coal miner height adjustment system.The results show that the improved control strategy can effectively improve the tracking accuracy and response speed,overcome the external load disturbance and uncertainty of the system,and is more suitable for the automatic height control of drum.(3)Based on the above research basis,the automatic height control technology of drum is combined with the modules of height adjustment system safety height value and cutting danger coefficient,and the simulation experiment of adaptive height adjustment of shearer is carried out.The results show that the automatic height control system of shearer can effectively adapt to the change of coal rock working conditions during the memory cutting process,reduce the load impact under the sudden situation,and ensure the safe and efficient cutting operation of shearer.