Study On Energy Management Of Pure Electric Tractor Based On Super Capacitor Auxiliary

With the increasing depletion of fossil fuels such as oil and the vigorous advocacy of new energy by the state,the agricultural machinery will also develop towards “electric” and “intelligent” in the future.But at present,there are still some shortcomings in the research of electric tractors,such as short operation time and insufficient power.In this paper,a large capacity supercapacitor is installed on the power supply of the traditional electric tractor.The energy management strategy is designed for this kind of composite power supply.The rationality and generality of the strategy are studied.The main performance of the new type electric tractor is analyzed.The main contents of this paper are as follows:(1)The inherent characteristics of the components of the composite power supply are analyzed,and the influence of different power combination forms on the overall performance of the composite power system is analyzed,and the composite power structure scheme of the electric tractor is determined.(2)The load characteristics of electric tractors are analyzed,and the mathematical modeling of the resistance of electric tractors in typical working conditions is established.According to the load characteristics,the demand power of the motor is calculated,and the other key parameters of the motor are determined,and the key parameters such as the related parameters of the power battery and the super capacitor,the speed change ratio of the variable speed box and so on are determined.(3)The simulation conditions of transportation,rotary tillage and ploughing cycle are worked out,and the fuzzy control rules and membership functions of the composite power supply are formulated.The simulation model of the composite power supply is combined with the CRUISE.Finally,the generality of the strategy is verified.(4)The simulation results of various working conditions are analyzed,and the changes in performance of electric tractors after adding supercapacitors are compared and analyzed.The particle swarm optimization is used to optimize the parameters of the control strategy,and the effect of the control strategy improved by particle swarm optimization on the 100 km energy consumption rate of ploughing operation is expounded.This paper also evaluates the dynamic performance of the whole vehicle and the time of one charging operation under the condition of transportation and rotary tillage,and the traction power and traction power of the electric tractors after the plow are greatly improved,especially in the tractor ploughing,which reduces the number of large current discharge of the power battery.