Research On Torque Control Strategy Based On FSEC Electric Racing

In recent years,the number of cars is increasing,and the relationship between cars and people is getting closer and closer.However,traditional fuel trucks bring about environmental pollution and noise pollution.At the same time,the country’s oil reserves have become tight.In order to solve these problems,the state has increased the development and research of pure electric vehicles.The control strategy is particularly important in the research of electric vehicles,which affects the power,economy and driving comfort of the vehicle,and is the core of the vehicle controller.Formula racing for undergraduates of our university is taken as the research object of this paper,and the torque control strategy of racing is taken as the core to carry out the research.The performance index of the whole vehicle is formulated,and the main power components are matched based on the model.The matching car is simulated to verify the rationality of the matching.In this paper,the torque control strategy based on fuzzy control algorithm is proposed;the design and development of hardware and software of the controller are completed;the proposed strategy is verified in real vehicle.The main contents of this paper are as follows:(1)By comparing the characteristics of different power system layout,the power system layout suitable for the racing car studied in this paper is determined;the driving motor,power battery and other parameters are matched according to the set vehicle performance index;the communication network of the whole vehicle is designed;the model of racing car and race track is established by Optimum Lap,and the matched components can meet the set performance index by dynamic simulation.(2)The whole vehicle control system structure of the car studied is introduced,and three torque control strategies are put forward,which are power strategy,conventional strategy and economic strategy.They all adopt the basic idea of reference torque plus optimized torque.The driver’s intention is identified by three variables: accelerator pedal opening,motor speed and change rate of accelerator pedal opening,and the reasonable expected target torque is calculated by fuzzy control algorithm.The model of fuzzy control is established by Simulink,and the corresponding embedded code based on C language is generated after simulation.According to the difference between power and reference power,the reference standard of different strategy conversion is formulated.(3)In this paper,the hardware and software of the control system are designed.In terms of hardware,the minimum system board with stm32f1 as the core chip is designed,including clock circuit,Download debugging circuit and other basic functions;can communication circuit,instrument display circuit and data storage circuit are designed.In terms of software,the FreeRTOS operating system is transplanted.Based on the modular idea of software design,the system is divided into management program,task layer program and function layer program,and the layout,design and implementation of each layer are completed.(4)Based on the electric program racing car of our university,a real vehicle test is designed to analyze the dynamic performance of the vehicle and verify the effectiveness and reliability of the proposed strategy.