Multi-objective optimization for cutting performance of the variable speed cutting shearer under different conditions

In order to realize the safe operation and high efficiency production of the shearer under different condi- tions,using the traction speed and cutting speed as the design variables,using the dynamic loads of gears,coal mining productivity,lump coal percentage as well as cutting energy consumption as the sub-goals,a multi-objective optimiza- tion model of cutting performance is established. Then,an optimization method for the weight coefficients selection of the different cutting performances is proposed based on the weight coefficients transformation,to determine the opti- mum weight combination for different conditions. Finally,the optimization calculation is conducted based on genetic optimization algorithm,and the optimal motion parameters with the change of cutting resistance are obtained under nor- mal coal seam,gangue coal seam and rock fault condition. Besides,a comparative analysis of cutting performance of shearer based on the optimal motion parameters control and traditional traction speed control is conducted. Research results indicate that compared with the traditional traction speed control,not only the economic performance of shearer under normal coal seam and gangue coal seam is obviously improved,but also the fault zone can be cut through safely and rapidly by adopting the optimal motion parameters control;besides,the local resonance of cutting transmission sys- tem is appeared when the drum speed is 24 r / min,hence it is necessary to avoid running at the resonant speed when the drum is variable-speed cutting. The obtained results lay a theoretical basis for the implementation of the adaptive variable speed cutting of drum shearer.