液压机械无级变速传动拖拉机虚拟试验平台设计

Design of Virtual Test Platform for Hydro Mechanical Continuously Variable Transmission Tractor

采用计算虚拟试验技术搭建无级变速拖拉机虚拟试验平台,缓解液压机械无级变速器(HMCVT)研究中实物试验存在的成本高、周期长及试验场地限制问题。以模块化和参数化建模的方法,将拖拉机系统划分为发动机模块、HMCVT模块、中央传动模块及行走机构模块,搭建了虚拟试验平台。采用神经网络建立发动机模型,采用动力学方程建立液压机械无级变速器、中央传动和行走机构模型,采用状态流图(stateflow)建立HMCVT控制模型;应用MatLab的Simlink和Simscape工具实现各个模块的仿真模型搭建,利用GUI工具设计虚拟试验平台控制界面,实现了两种多段HMCVT实例的换段控制过程的虚拟试验。结果表明:两种HMCVT虚拟试验结果与理论分析一致,试验平台对多种HMCVT进行虚拟试验具有有效性和通用性。

The virtual test platform of HMCVT tractor was built by using the virtual test technology to alleviate the problems of high cost,long cycle and limited test site in the research of HMCVT.The tractor system is divided into power source module,HMCVT module,central transmission module and traveling mechanism module by the method of modularization and parametric modeling,and a virtual test platform is built.Among them,neural network is used to build the power source model,dynamic equation is used to build the model of HMCVT,central transmission and walking mechanism,state flow is used to build the HMCVT control model,and Matlab's Simlink and Simscape tools are used to build the simulation model of each module,GUI tool designs the control interface of virtual test platform,and realizes the virtual test of two kinds of multi-stage HMCVT cases in the process of changing stage control.The results of the virtual test of two kinds of HMCVT are consistent with the theoretical analysis,which shows the effectiveness and generality of the virtual test platform for a variety of HMCVT.