The Study On Key Technologies Of Real-time Control In Powertrain Domain Of Hybrid Electric Pickup Truck

With the steady progress of the Rural Revitalization Strategy in China and the rise of urban agriculture,the consumption of farmers in purchase vehicles is growing rapidly.In particular,pickup trucks which include the functions of cars and agricultural transport have become the first choice for people.To achieve the "dual carbon" goal,reduce fossil energy consumption,hybrid-powered pickup trucks take into account energy saving and environmental protection,and have already become one of the effective technologies to relieve the pressure of resources and environment in China.With the rise of urban agriculture,hybrid electric pickup trucks are going to be more and more popular among people.This study takes a hybrid electric pickup truck with a P1+P3 structure as the research object,matching a four-cylinder direct-injection dedicated gasoline engine for HEV,and develops air/charging system control of gasoline engine and HEV real-time control based on modelbased design method,and carry out bench test,which is to realize the deep integration of engine control technology and vehicle control based on advanced algorithms,and then provide theoretical basis and technical reference for the ASW development of Powertrain domain control unit(PDCU).This paper uses Matlab/Simulink to establish the P1+P3 HEV forward simulation model;Combined with the analysis of the power flow and mode of the powertrain system,a hierarchical PDCU application layer software architecture is designed based on the functional safety concept and the torque architecture of vehicle control reuses the torque architecture of engine control,which creates a good environment for the distributed development of electronic control software,models integration and algorithm fusion.The Hardware in the loop(HIL)verification platform was built,and the vehicle model was checked and verified,laying a foundation for the comparison and verification of vehicle control algorithms.The feedback linearization technology with IMC-PID is used to improve the traditional intake system control for a four-cylinder HEV dedicated engine.Compared with the traditional MAP-based PID control strategy,the main advantage of this method is to reduce calibration workload.The control technology is based on the non-linear dynamic physical model of gasoline engine air/charging system,applying feedback linearization technology to decouple the interaction between actuators,and adding a linear control module to ensure transient and steady-state performance as well as closed-loop robustness.Transient test results show that the controller can coordinate the actuator to achieve the targets and to reduce the calibration workload.The real-time control of the hybrid vehicle is designed based on the Dynamic Programming(DP).The DP is used to solve Driving Cycle to obtain the optimal trajectories,extract the shift strategy and use the Model-Based Calibration method(MBC)to generate the optimal MAP;In order to realize the estimation of all the optimal trajectories and maximize that the potential of the power battery,combined with the Charge and Discharge Reaction(CDR)of the battery,a Feedback Energy Management System(FEMS)is built with SOC as the feedback variable.Then,to realize the full use of energy stored in the battery,combined with the Charge Depletion-Charge Sustain strategy(CD-CS),the reference SOC is involved;Finally,a comparative simulation on this real-time controller is conducted against DP,the results show that the FEMS has good control performance,the SOC can better follow the reference SOC,and it has better fuel economy.This method realizes the estimation of all optimal trajectories,and realizes the optimization of energy management for different initial SOC value of vehicles to adapt to the complexity of rural driving conditions.In order to reduce the calibration workload,adapt to distributed development and improve the adaptability of the system,the real-time control based on DP-ECMS is proposed,that is,on the basis of the FEMS,the parallel mode is realized by modular ECMS.The modular ECMS framework takes the minimum global energy consumption as the objective function,and applies the Pontryagin’s Minimum Principle(PMP)to solve the optimal control of each subsystem separately,which can solve each mode(series,parallel,one/two motor direct drive)optimal control problem.Finally,the DP-ECMS-based vehicle control is verified by Hardware in the loop(HIL).The results show that the real-time controller of the vehicle based on DP-ECMS has good control performance and good robustness,the SOC can follow the reference SOC much better,and the fuel consumption value is close to the simulation results of the DP-based real-time control and the DP offline simulation,and better than the rule-based control strategy.It further enhances the applicability of agricultural hybrid electric pickup trucks to the complex rural road conditions.