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This paper studies the structure and principle of tractor automatic mechanical transmission shift actuator with the type (electronically controlled hydraulic). Tractor AMT shift actuator mechanics model and mathematical model are set up. Dynamic analysis of shift process is finished. The method of solving contradiction between shift time and shift impact in shift process is presented. Through analysis of shift process, optimal hydraulic control law could be found out by applying optimal control theory. The most short time shift with low impact even no impact is realized.

In this paper, the fuzzy control strategy is introduced, and then it proposes a two-dimensional fuzzy control method which takes the tractor driving wheel slip ratio and the engine throttle opening as input variables, while uses gear correction as output variable. Based on these, a fuzzy controller is designed to optimize the law of downshifting of tractor AMT. Subsequently, a best tractor AMT shift rule is formed through optimal combination of resolution obtained by the law of up-shifting. At last, simulation analysis is made on the basis of the simulation model established of tractor AMT shifting process. The results show that shift cycle can be effectively avoided and shift shock will reduced in the process of shifting, which makes the quality of shifting better and greatly improve the performance of the tractor.

According to the low speed and high torque characteristics of tractor, the paper discussed the application feasibility of the lock pin synchronizer in tractor, and analyzed its running principle and working process. The 3D model of synchronizer is established based on Pro/e software. The dynamic simulation of the synchronizer’s working process is made by the multi-body dynamics analysis software ADAMS. The dynamic simulation curves reflected synchronizer properties such as angular velocity, friction torque and the synchronization time. After being compared with the theoretical calculation value, the results show that there are only some smaller errors exist between theoretical value and simulation value, which verified the accuracy of simulation model.

Based on the analysis of the characteristics of tractor clutch and the engagement process at start-up working condition, the dynamics model of the clutch start-up working condition is established, then clutch engaging control approaches are discussed with emphasis, therefore the clutch engaging control law of “fast-slow-fast” is obtained. According to the clutch control strategy, clutch simulating analysis of an AMT tractor at the starting conditions will be in process by Matlab/Simulink on the basis of well design of fuzzy controller. The analysis result shows that the use of fuzzy control theory could effectively control the engagement process of AMT tractor clutch at start-up working condition.

The change of H/O mixture ratio has affect on the combustion of H/O mixed gas in the micro combustor, and the temperature distribution of the micro combustor wall are researched in this paper, when the mixed gas flux is different in the combustor of the micro thermophotovoltaic system. The result of the test indicates that H/O mixed gas can combust stably in the micro combustor. As mixed gas flux is 3.92g/h and H/O mixture ratio is 2, the temperature of the micro combustor wall is about to 1100K, which matches work requirement of the micro thermophotovoltaic system.