Analysis and application of functional safety based on modified FMEA method

According to the requirements of ISO 26262, the functional safety analysis of the corresponding system, the use of hazard analysis and risk assessment of the system has different functions and their corresponding failure of the car safety integrity level (ASIL, Automotive Safety Integrity Level). Then, the modified FMEA method based on fuzzy rule base and gray relational degree is introduced into the functional safety analysis. Taking the BMS (Battery Management System) as an example, the fuzzy rule based of BMS is established, including fuzzy language term set and the corresponding fuzzy number, and the FMEA group to evaluate the various failure modes, and then use the gray correlation theory to calculate the correlation degree of various failure modes, by sorting to determine the risk of failure mode sequence, in general, the failure mode with the higher the risk ranking, the higher the ASIL level.