基于拖拉机燃油经济性HMCVT换挡规律的研究

通过分析拖拉机燃油经济性指标和拖拉机经济性的影响因素,提出一种以拖拉机燃油消耗率最低和牵引效率最高为目标的燃油经济性换挡规律。根据拖拉机燃油最佳经济性,结合液压机械无级变速器(Hydraulic mechanical continuously variable transmission,HMCVT)的结构和传动特点,阐明实现拖拉机燃油经济性的要求。探究一种发动机燃油消耗率和液压机械无级变速器的传动效率之比最小为目标的经济性最佳的HMCVT下的发动机转速转矩曲线,通过与发动机外特性曲线比较,可以使各挡位都处于油耗最低的经济性区域,并保证拖拉机的速度稳定,符合经济性换挡规律。

Research of Shift Law of Tractor HMCVT based on Fuel Economy

Through the analysis of tractor fuel economy index and the influence factors of tractor economical efficiency,a kind of fuel economy shift rule with tractor minimum fuel consumption and traction as the goal of most efficient is put forward.According to the optimal fuel economy of the tractor,combined with the structure and transmission characteristics of the hydraulic mechanical continuously variable transmission(HMCVT),the requirements of realizing the fuel economy of the tractor are expounded.A kind of shift rule with optimum economical efficiency of HMCVT is explored,which taking ratio of engine fuel consumption to transmission efficiency of HMCVT is the smallest as the objective.By using the SimulationX,the simulation is carried on,it is concluded that the engine speed torque curves under various gear,through compared with outside the engine characteristic curve,can make all the gears are at the lowest fuel consumption economy area,and guarantee the stability of the speed of the tractor,conforms to the economical shift rule.