Research And Design Of Driving Torque Control Strategy Of Vehicle Control Unit For Pure Electric Vehicle

With the increasing of energy crisis and environmental pollution,the development and application of pure electric vehicle is the trend of the development of automobile industry.At present,the development trend of pure electric vehicles is toward the direction of intelligent and lightweight.Therefore,as one of the key technologies and cores for the sustainable development of pure electric vehicles,the performance of the vehicle controller directly affects the performance index and intelligence degree of pure electric vehicles.However,there are still technical obstacles and driving performance control problems in the intelligent control of pure electric vehicles,so in order to solve the existing practical problems,a variety of pure electric vehicle vehicle control strategies emerge at the right moment.At present,the research on the vehicle control strategy for pure electric vehicles is still in its infancy in China,mainly focusing on the framework design and the research and development of the underlying hardware architecture.Based on a miniature pure electric vehicle,this paper analyzes the research progress of the complete vehicle controller of pure electric vehicle and its strategy.Aiming at the power demand and existing problems of the pure electric vehicle under the driving condition of flat road and climbing condition,the research and design of the complete vehicle control strategy of the vehicle under two typical working conditions are carried out.By applying the fuzzy control algorithm to the decision-making process of the driving torque of the vehicle,the intelligent control strategy of the vehicle under multiple working conditions is realized.The main research and design contents of this paper are as follows:1.The current development status of pure electric vehicles and their complete vehicle controllers is reviewed.By studying the development trend and application of the whole vehicle controller of pure electric vehicles at home and abroad,the main existing problems are analyzed,and combined with the development trend of intelligent and lightweight pure electric vehicles,it is proposed that the whole vehicle control strategy should be optimized towards the direction of multi-working condition dynamic performance adaptation.2.By studying the complete vehicle control system of pure electric vehicles and the vehicle’s power demand under different working conditions,a complete vehicle control strategy is designed to make the vehicle adapt to the power demand and drive safely under various typical working conditions.By identifying the operating condition of the vehicle in the process of driving,the reference power demand is determined according to the torque MAP evaluation method,and the power compensation is carried out to different degrees by combining with the fuzzy control,so as to increase the power performance and multi-operating condition adaptability of the pure electric vehicle.3.The fault handling strategy for different working conditions is designed,which does not affect the normal running and operation of the vehicle,and has the advantages of simple design,high reliability and high driving safety performance.After completing the design of the above research content,in order to verify the feasibility and performance of the vehicle controller and its strategy,the MATLAB modeling and simulation analysis and the test and verification of the vehicle test platform were carried out.Through the analysis of experimental data,the maximum speed controlled by the vehicle controller designed in this paper reaches 110km/h,the acceleration time of 100 km is 14.8s,and the maximum climbing slope is 25%.From the perspective of the vehicle’s dynamic performance,the control strategy designed in this paper also improves the overall performance by 20% compared with the traditional single torque MAP strategy.On the basis of ensuring the safety of vehicle driving,it improves the overall dynamic performance and also reflects its practical value in the control system of pure electric vehicle.