The Design Of Power Battery Testing Platform Based On Real-time Simulation Of Electric Vehicle

Human is facing a series of problems,such as climate warming,energy shortage,air quality and so on.The traditional internal combustion engine vehicle is one of the important reasons causing these problems,since the beginning of this century,the rapid development of electric vehicles can greatly ease the pressure.Pure electric vehicles can achieve low emissions and even zero emissions,low heat,low noise and other environmental characteristics,therefore,pure electric vehicle market share is also increasing year by year.The electric vehicle is composed of three parts:power battery,drive motor and electric control system.The dynamic performance of electric vehicles is directly dependent on the performance of the power battery,so the researchers have been devoted to the research and development of power batteries.As the development process of power battery,it is necessary to test the performance of the power battery.Based on this situation,this paper designs a set of test platform to realize the objective while simulating the actual running condition of electric vehicle.In consideration of the running condition of electric vehicle is very complicated,the nonlinear and multi factors of the characteristics of the test bench,and it is difficult to accurately simulate the vehicle inertia and so on.the test platform needs to achieve dynamic loading,dynamically test the operation of the power battery,and be provided of enough robustness and certain overload capacity,In order to ensure the smooth operation of the test platform,and this is why we decide to build this test platform.In the design process of the test platform,the vehicle friction resistance,the air resistance,the climbing resistance and the accelerating resistance are simulated by flywheel group and AC electric dynamometer.In this paper we consider employing dynamometer and flywheel group co-simulating load,and that the flywheel simulates the equivalent moment of inertia of the electric vehicle,the remaining part is implemented by brake dynamometer,the effect turn out good through the combination of dynamometer and flywheel group mode,the system is more stable.According to the reference speed curve,the control speed of the motor is obtained from the physical model of the test platform to control the driving motor,to ensure the drive motor can work safely under certain overload condition.The research content of the article:(1)According to the structure of the electric vehicle driving system,the dynamic model of the electric vehicle is built,and and on this basis,the overall structure of the electric vehicle power battery testing platform is built,and the whole frame of the power battery testing platform is designed.(2)The mathematical model of the test platform is analyzed,and the power of the test platform is calculated,and the main components of the test platform are selected.(3)The data acquisition and communication network system of test platform is built and analyzed,the CAN bus communication is adopt for the communication system of the overall test platform framework.(4)Then the equivalent inertia of electric vehicle is analyzed and calculated,based on the equivalent inertia of electric vehicle,the flywheel group of the test bench is designed according to the classification formula.Then the control strategy of the test platform and electric vehicle simulation running mode is designed.(5)According to the designed testing platform to build a small test platform,in order to verify the validity of the design testing platform,and testing the voltage of single battery and the temperature of the power battery,preliminary determines that the simulation of electric vehicle real-time condition of power battery testing platform design scheme has good application value.