Study On Active Power-off Protection System Based On Rear-end Collision Of Pure Electric Vehicle

In the past decade,the new-energy automotive industry of China has entered a period of rapid development.With new energy vehicles appearing more frequently in China's road traffic,high-voltage electrical safety issues such as fires,explosions and electric shocks caused by collisions of BEV in HVS have become "new problems"needs to be solved urgently.This paper takes a micro battery electric vehicle as the research object,and designs an active power-off protection system based on full overlapping rear-end collision to solve the high voltage security risk of battery electric vehicle.The main research work shows as follows:(1)Evaluating the high voltage risk of BEV under full overlapping rear-end collision.Establishing a FE model of the miniature BEV and its HVS to ensure that the model can well evaluate the electric safety risk of BEV in crash simulation.Establish a fully overlapping rear-end collision model,and use CAE and mathem-atical models to analyze the key parameters that affect the safety of high-voltage electric vehicles.The working condition matrix of rear-end collision test is established based on key parameters,which provides the data basis for predicting the power safety risk of the active power-off protection system.(2)Design an active power-off protection system based on full overlapping tail-to-tail collision.The active power cut protection system is mainly divided into three modules.Sensing module,designing the important parameters of the sensor and the installation location to meet the environmental awareness requirements of the active power-off protection system;Control strategy module,which can evaluate the high voltage security risk of rear collision by using active power-off strategy module and make decisions based on the information obtained by the vehicle sensor;Execute module,execute the electrical cut signal to avoid power loss in advance.The situation of high voltage electrical appliances being charged in time.(3)The intelligent algorithm is used to identify the key parameters in the active power outage protection system,so that the power outage protection control strategy can accurately judge the safety risk of high voltage power in time.According to the real-time data obtained by the vehicle sensors,the quality ratio of the front and rear vehicles during the rear-end collision is analyzed to improve the accuracy of the active power-off protection system,which is using BP network.(4)The active power-off protection system was verified by joint simulation based on the active and passive safety integration research ideas.First,the control strategy of the collision warning system is validated through the joint simulation of Carsim and Simulink to ensure the timeliness of the active power-off control strategy.Next,LS-DYNA software is used to evaluate the high-voltage power safety risk of battery electric vehicle after rear-end collision to determine the accuracy of the active power-off control strategy.