In order to adjust shearer drum swiftly and precisely to adapt to the changes of coal seam, a compound control approach based on cerebellar model articulation control and fractional order PID controller was proposed. As the movement precision and response speed of hydraulic system were determined mainly by the control precision of valve-controlled asymmetrical hydraulic cylinder, its working principle and characteristics were analyzed in this paper, with particular focusing on the asymmetry problem. Furthermore, RBF neural network was applied to obtaining reasonable tuning parameters and a control algorithm of proposed controller was designed. Finally, laboratory experiments were developed to verify the validity and effectiveness of proposed compound control method. The testing results, compared with those for other controllers, proved that the proposed compound control method can acquire high movement precision and respond speed in the system of hydraulically driven shearer drum lifting with different control conditions. 1. Introduction With the development of coal mining technology and stringent requirement for colliery safety, the automation control of fully mechanized coal face has become an inexorable trend. As the core mining equipment, shearer plays a decisive function in achieving safe and high-efficiency exploitation, and its automation control is always an interested research subject in coal mining field [1]. With years of development, many researchers have proposed the technology of memory cutting to achieve the automation control of shearer [2–5]. However, the control effect of memory cutting depends on the performance of hydraulic adjustment height system of shearer drum. As one of the most important constituent parts in shearer automation control system, its performance directly affects the efficiency and reliability of coal mining. It is noteworthy that hydraulically driven shearer drum lifting has become one of the key technologies to improve the performance of hydraulic system [6]. The hydraulically driven shearer drum lifting is that when the shearer is working, the drum height is automatically adjusted along the coal-rock interface of coal face to avoid cutting rock. It can improve the quality of coal production and extend the service life of shearer. The lifting of drum height is achieved through the displacement of hydraulic cylinder piston. Due to different mining geological conditions, the coal seam thickness between roof and floor has a great discrepancy. Therefore, the hydraulic cylinder is needed to carry on a fast response to
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