电动机加液力变矩器驱动下的采煤机性能分析

摘要

目前采煤机主要采用电动机加变频器的驱动方式牵引,难以满足低速截割复杂煤层时需要更大输出转矩的要求.针对该问题,分析了采用电动机加液力变矩器驱动方式时采煤机的性能,对电动机与液力变矩器的合理匹配进行了理论分析并建立了相应的计算模型.以MG750/1860-WD型采煤机为例进行匹配分析,得出结论:电动机加液力变矩器的驱动方式在一定速度范围内可以实现采煤机牵引的无极变速及采煤机在不同工况下的截割牵引;与变频牵引相比,在相同截割牵引速度下,采用液力变矩器截割牵引可增大输出转矩,且液力变矩器的输出转矩随着牵引速度的降低而增大,最大输出转矩远超过变频牵引的最大输出转矩;在低速截割牵引条件下,液力变矩器截割牵引可以提高行走轮的输出转矩,增大采煤机的牵引能力,对于截割薄煤层和阻力较大的煤层具有重要意义.%Currently shearer is mainly driven by motor and frequency converter,and it is difficult to meet requirement of larger output torque when cutting complex coal seam at low speed.In view of the problem,performance of shearer driven by motor and hydraulic torque converter was analyzed.Reasonable matching between motor and hydraulic torque converter was analyzed and calculating model was developed.MG750/1860-WD type shearer was taken as an example for matching analysis,and results are as follows:driving mode of motor and hydraulic torque converter can realize stepless speed change of shearer traction within a certain speed range and cutting traction of shearer under different conditions;compared with frequency-convention traction,at the same cutting speed,cutting traction with hydraulic torque converter can increase output torque which increases with reducing of traction speed,and the maximum output torque of hydraulic torque converter greatly exceeds that of frequency converter;and under the condition of low speed cutting traction,cutting traction with hydraulic torque converter can increase output torque of walking wheel and increase traction capacity of shearer,which has important significance for cutting of thin seam and coal seam with large resistance.