Research On Simulation Method Of Driving Load Of Hybrid Electric Vehicle Transmission System

Vehicle transmission system is an important part of hybrid vehicles,and its performance directly determines the power,fuel economy and driving comfort of the car.The means to verify and evaluate the performance of the transmission system mainly include indoor bench dynamic simulation test and real vehicle road test.The indoor bench dynamic simulation test has the advantages of short cycle,small input,convenient and reliable test,and wide application range.The driving system simulation test technology of the transmission system is the key technology for simulating the actual driving condition of the vehicle on the indoor gantry,and it is also one of the key technologies for the large gap between china’s automobile industry and foreign countries.Due to the complexity of the hybrid vehicle transmission system structure and control strategy,it puts forward higher requirements for the driving load simulation method,and the current transmission system driving load simulation method can not meet the indoor bench simulation test requirements.Therefore,the paper focuses on the systematic research on the driving load simulation method of hybrid electric vehicle transmission system,and proposes a driving load simulation method based on RPC(remote parameter control technology)to improve the reproduction accuracy of the driving load.And the research and development and testing of parts and components have important theoretical significance and engineering application value.Firstly,based on the collection of relevant literatures at home and abroad,the composition of the hybrid vehicle transmission system is analyzed with a hybrid vehicle transmission system.The motor control strategy and the drive system control strategy are analyzed,and the hybrid vehicle transmission system is established.Load simulation system solution.Based on the modular modeling method of physical concept,the drive system model,transmission system model and load system model were established by using MATLAB/Simulink.Combined with the drive system control strategy,the integrated analysis model of the load simulation system of hybrid electric vehicle transmission system was established.Then,through the integrated analysis,the time-domain dynamic response characteristics of the load simulation system are extracted with typical signals such as sinusoidal signals and step signals as inputs.The MATLAB/Ident toolbox is used toidentify the load simulation system,and the transfer function of the system is obtained.Get the Bode diagram of the system through the Linear Analysis tool.On this basis,the dynamic response characteristics of the load simulation system are analyzed and evaluated from the time domain,frequency domain and Lagrangian domain.Secondly,combined with the dynamic load simulation integrated analysis model and RPC technology of hybrid vehicle transmission system,the frequency response function estimation method for non-parametric system identification and the remote parameter loading control method using load frequency domain simulation iteration are deeply studied.The frequency response function algorithm and the remote parameter loading control algorithm are programmed by MATLAB.Combined with nCode software,the algorithm is compared and verified,and the compiled algorithm is embedded into the integrated analysis model of the hybrid vehicle transmission system load simulation system.A driving load simulation method for hybrid electric vehicle transmission system based on RPC(remote parameter control technology)was established.On this basis,the NEDC load case cycle is analyzed.Load simulation control and iteration,and compared with the traditional PID control results.The established method is obviously superior to the traditional PID control,which improves the simulation tracking accuracy of the NEDC working condition cycle.Thirdly,a real-time data acquisition system for hybrid vehicles was established.According to the needs and specifications of the enterprise,a dynamic load spectrum was collected at a domestic automobile test site,and the load spectrum was analyzed and processed.The dynamic load spectrum is used to simulate the expected response signal of the dynamic load.Combined with the integrated analysis model of the load simulation system,the dynamic load spectrum simulation iteration is carried out,and the dynamic load is simulated with high precision.The dynamic load simulation method of the hybrid vehicle transmission system is established.Finally,combined with the proposed load simulation system of hybrid electric vehicle transmission system,the load simulation test bench system was built and the dynamic load loading software was compiled.The simulated dynamic load spectrum is taken as the expected response signal,and the simulation test is carried out.The test results verify the effectiveness of the RPC-based driving load simulation method.