Simulation based safety assessment of on-board power systems

On-board power systems are containing and connecting safety critical electronic components of vehicles. They are powering the electric drivetrain in electric and hybrid vehicles and are connecting the parts of the E/E architecture. Thereby on-board power systems become itself a safety critical part of the overall architecture. Thorough investigation of the failure modes, diagnosis, and failure effects are therefore mandatory in order to evaluate functional safety of the overall system.
This process of failure effect analysis is conventionally done and documented manually. For a large number of architectures potentially fulfilling the topological requirements a detailed safety analysis is quite time consuming and error prone. In order to avoid manually introduced errors during the safety assessment process it is mandatory for high safety integrity levels to utilize a fault injection methodology. Especially for a large number of topologies as they appear in on-board power systems this can efficiently be done based on simulations. In this contribution a framework is presented to automate the efficient initiation, execution, and evaluation of fault simulations of on-board power systems. Based on a system level hardware description language faults are injected at run time which leaves the nominal design description unaffected. A wide range of typical faults can be configured in terms of parameters like location, type, duration, frequency. After automatic execution of the required simulation tasks several safety metrics like e.g. diagnostic coverage are presented to the user.
Thereby it is possible to automatically validate correct detection of possible faults and effectiveness of the implemented safety measures for the design space of feasible topologies. This allows fast comparison of different topologies with respect to their safety integrity and therefore efficient functional safety assessment of on-board power systems.