Research On The Control System Of HT20 Crawler Carriers With Hybrid Transmission

The crawler carriers are a transport-type construction vehicle that can transfer goods in a harsh environment.At present,there are fewer types of domestic crawler carriers,and the existing models mostly adopt hydrostatic transmission driving systems,which have the disadvantages of low transmission efficiency and narrow variable speed range.The hydraulic mechanical hybrid transmission system can effectively make up for these deficiencies so that crawler carriers have the advantages of high transmission efficiency,wide variable speed range,stepless speed regulation and flexible steering.In this thesis,the HT20 hydraulic mechanical hybrid transmission crawler carriers is taken as the object,and its driving control system and control technology are studied.Based on the analysis of the working principle and working conditions of the hydraulic mechanical hybrid transmission crawler carriers,the functional requirements of the control system are proposed.Based on this,the control system scheme is determined.The input and output signals and software composition of the control system are analyzed,and the controller hardware pin assignment diagram is painted.Through the speed regulation performance analysis of the driving system with independent driving on both sides,the speed control scheme of its three gears is determined.The driving gear,speed,straight line correction and limit load control algorithm are formulated.Through the kinematic analysis of the steering of the driving system,the three differential implementations are compared and the inner deceleration is selected.The adaptive differential steering algorithm for changing driving speed is proposed and the algorithm flow is given.In order to improve the economic performance of crawler carriers,two modes of power and economy were proposed.The parameters matching strategy of power and transmission system under two modes was studied.Energy-saving control algorithm for joint adjustment of engine and hydraulic system parameters is proposed for economic model.