The Strategy And Software Design Of The Central Controller Of Electric Tractor Driven By Dual Motor Coupling

With the consumption of non-renewable energy sources such as oil and coal,the resulting energy crisis and environmental pollution problems have intensified.The biggest advantage of electric tractors is zero emissions and low noise.At the same time,the motor drive makes it change from adjustable during movement to precise and controllable.The most critical component is the central controller.This paper uses software strategy simulation and test bench verification methods.The strategy and software and hardware design of the dual-motor coupling-driven electric tractor central controller include:(1)For the dual-motor coupling drive mode of electric tractors,the overall plan is designed.Determine the control relationship between the controllers and the amount of input and output transmitted.Through the analysis of the force of the electric tractor’s whole machine during the ploughing operation,the power transmission path and distribution are obtained.Combined with the design requirements of the electric tractor,it provides a basis for the selection of key components and the construction of the drive control strategy model.(2)According to the force analysis,the demand torque is divided into three parts:speed demand torque strategy,traction demand torque strategy and suspension compensation torque strategy.Using the fast optimization ability of particle swarm optimization algorithm,two motor torques are used as particles.Aiming at the highest motor efficiency,search in the motor efficiency curve.Design torque distribution algorithm based on linear decreasing weight particle swarm optimization algorithm.Finally,the input information integration strategy and work mode judgment strategy are designed to complete the design of the drive control strategy.Under different vehicle speeds and required torques,the simulation is compared with the standard particle swarm optimization algorithm.The torque distribution algorithm based on linear decreasing weight particle swarm optimization algorithm has better speed and ability.Simulate the drive control strategy,analyze the relationship between the accelerator pedal opening,brake pedal opening,output torque,driving speed and other control variables to verify the rationality of the drive control strategy.(3)Complete the software design of the central controller in Code Warrior software,including the bottom driver and application layer program.The bottom driver program mainly includes phase-locked loop program,signal acquisition program,MSCAN communication program.The application layer program includes the design of the main program overall design,power-on self-test,fault handling,working condition judgment and other modules.According to the information requirements of the control strategy,complete the selection of the micro-control chip of the central controller,and design the minimum system circuit and peripheral circuits around the micro-control chip.(4)Debug the central controller,connect key switches,pedals and other components,and verify the realization of software functions through the LCD screen.According to the structural characteristics of the dual-motor coupling drive of the electric tractor,the whole test bench and test plan are designed.Complete the construction of the test bench of the central controller,and obtain curves such as driving speed,coupled output torque,output torque of two motors,and efficiency of two motors.Through the comparison between the test and the simulation,the average error of the test bench relative to the simulated travel speed is 7.62%,and the average error of the coupled output torque is 2.79%.The test comparison results show that the control strategy meets the demand and has a better control effect and torque distribution capability.