Study On Technology Of Double Side Motors Coupling Drive Transmission For Tracked Vehicle

Electric drive technology for tracked vehicle has become an important research direction at present, because it corresponds to the environmental-friendly pursuit and can improve vehicle mobility obviously. It already has achieved good practical results currently in the aspect of electric cars. Compared to wheeled vehicle,tracked vehicle is heavy, cramped inside and its transmission with more functions. So it require higher power index, power to volume ratio, power weight ratio. In the limited level of technology under the premise parts,it’s important to integrate motors and machines effectively,and realize of functions of power transmission and steering and brake and so on. And the research content of this is the transmission technology. This paper started from the innovative design of the technical scheme of electric transmission for tracked vehicle. And design method of double side motors coupling drive transmission has been formed. At the same time, vehicle drive control technology and motor control technology for the new type of tracked vehicle electric transmission have developed. Therefore, the major works implemented in this paper are presentd as follows:Firstly, the views of advantages and disadvantages of the past basic configuration of electric drive tracked vehicle and the development of domestic and international electric drive tracked vehicle recently are presented. Through the analysis of relevant studies,it is noticed that the focus is on how to compound machine and multiple motors effectively to get optimum scheme for high-power electric drive transmission. And research progresses on the key technologies related to the electromechanical coupling driving are introduced.Secondly, a new double side motors coupling drive transmission scheme is put forward. Based on planetary transmission components comprehensive analysis method,the basic principle of component combination is given for power coupling mechanism scheme optimum seeking. And the rotational speed and torque mathematical transformation models are set up between input and output. A new characteristic parameter is put forward to represent renewable power utilization as a quantitative evaluation index. So in this paper the matching optimization model is built up and a suitable design method for double side motors coupling drive transmission is proposed.Thirdly, as the speed can be influenced by the variation of load in permanent magnet synchronous motor vehicle driving system, a two-order ADRC speed control system based on load observer is designed. The control system is combined with Active Disturbance Rejection Controller(ADRC) to observe and compensate for the load disturbance, which can suppress external disturbance. Simulation and experimental results show that ADRC governing system with load observer has stronger ability of anti-interference, and the dynamic performance and t he response performance of PMSM frequency control system have improved, which proves ADRC control system with load observer can better satisfy the control requirement of electric vehicle.Fourthly, the difficult problem of double side motors drive tracked vehicle straightly driving is solved by the method of combination of mechanical and control. Using the load power balance function, coupling mechanism can reduce 60%-80% of double outside load difference. That’s in large part thanks to coupling mechanism. On the aspect of control, compensation control algorithm and deviation coupling synchronization control strategy based on fuzzy PID are presented.Fithly, a decoupling algorithm of steering dynamics for double side motors coupling drive transmission for tracked vehicle is proposed. Thus, the steering system is transformed by dynamic decoupling control algorithm into the driving speed subsystem and the steering speed subsystem. In the forward speed subsystem, the desired speed and the current speed are used to determine the robustness sliding mode control algorithm in stabilizing the speed errors. And in the steering speed subsystem, the steering speed control algorithm is designed based on the fuzzy adaptive sliding-mode algorithm to ensure the tracking control of the reference steering speed. So a strong constraint relationship between two inputs of the coupling mechanism is set up. It can ensure the safety of the tracked vehicle during steering, meeting with the driving intention as far as possible.Sixthly, a directed acyclic graph model for task assignments control system is created. So the double motor coupling drive system control architecture is set up. Hardware-in-loop simulation verification platform and bench test platform are set up. Thus the principle of transmission scheme, control algorithm and the output performance are test by experimental verification.