Research On Functional Safety Of Battery Management System Hardware And Software Based On AURIX Platform

The automotive electronic control unit is increasingly complex,and the system failure rate and random failure rate of the battery management system are increasing,which not only affects the battery consistency,but also poses a serious threat to the safety of people and vehicles.Therefore,the functional safety research of the battery management system has Significance.In order to avoid the hazards caused by the failure of automotive electronic controller systems and random failures,the International Organization for Standardization has developed standards ISO 26262 for functional safety and many semiconductor suppliers have also developed chips that meet functional safety requirements.The paper studies the software and hardware functional safety of the equalization control system and other main modules in the battery management system.On the Infineon AURIX multi-core microcontroller platform,a battery management system that meets the functional safety requirements is designed.Firstly,based on the ISO 26262 functional safety development process,the important part of the battery management system is the research object,and the functional safety requirements are derived through the concept analysis.Based on this,the system architecture design and subsystem design are carried out,and the hardware architecture indicators are analyzed.Two random quantitative methods for random hardware failure metrics are used to verify the functional safety failure rate of the equalization control system design.Secondly,based on the AURIX multi-core microcontroller platform,the hardware architecture of the battery management system conforming to the functional safety requirements is established.The hardware circuits of the modules such as dual Microcontroller Unit power supply,data acquisition and CAN communication are designed,and the dual Microcontroller Unit module and power module are provided.Functional safety analysis was carried out,and the battery management system was finally welded according to the schematic diagram of each module.Thirdly,based on the AURIX multi-core microcontroller platform,the software architecture conforming to the AUTOSAR standard is established.Combining the advantages of the ampere-integration method and the open-circuit voltage method,the SOC estimation strategy based on the OCV-Ah method is proposed,and the ILLD underlying driver package is combined with the underlying driver.It was configured to eventually develop an operating system that conforms to the AURIX multi-core architecture.Finally,three different functional safety test methods were selected to verify the functional safety design of the battery management system software and hardware.Firstly,build the d SPACE hardware-in-the-loop test platform,test the safety mechanism of the battery management system by injecting four faults of equalization,overvoltage,undervoltage and disconnection,and then use the bench test to test the accuracy of the total voltage and the single voltage.Finally,the battery management system is integrated into the vehicle for charge and discharge SOC accuracy testing.The test results show that the battery management system developed based on AURIX multi-core microcontroller platform meets the functional safety requirements.