ISO 26262 Hazard and Risk Assessment for Hybrid Powertrain

ISO 26262 is an Automotive functional safety standard for Electrical and Electronic system. This paper details application of this standard for hybrid powertrain. The concept of functional safety has been analyzed. First item definition for hybrid powertrain is detailed out. Item definition includes system description, its function, boundary, interfaces to external systems. Hybrid powertrain is used to provide electric traction to the vehicle and to charge the included battery. Battery provides power to electric motor. Major components of hybrid powertrain are Generator, Traction motor, High voltage battery, Inverters and other auxiliary units. The overall powertrain scheme is being discussed from functional safety perspective. Then methods for identifying hazardous situations that could result from malfunctioning behavior at the vehicle level is presented. Each function is analyzed from hazard perspective and all hazards are identified. Identified Hazards are analyzed for different vehicle operating conditions and ASIL rating is identified for each hazard.