A shearer drum height adjusting strategy using sliding-mode variable structure control

As automatic height adjusting of the shearer was achieved by electro-hydraulic proportional servo control,established a height-adjustment cylinder model of the shearer,and deduced state space equation of the shearer height adjusting system,then designed an automatic height adjusting controller,in the controller authors adopted the controller sliding-mode variable structure control strategy,including the sliding function design and sliding control rule analysis.Finally,based on the state equation and the controlling function,authors simulated the shearer height adjusting controller,the results show that with the sliding mode variable structure control strategy,the automatic height adjusting become fast and stable.