State-Space Modeling of Protection Circuits for Electronic Fuses in Vehicular Power Systems

Zonal low-voltage vehicular power system archi-tectures with electronic power distributors are currently being researched. These distributors contain electronic fuses that inter-connect the power supply with loads such as steering or brake actuators. In this paper, methods for the design and evaluation of protection circuits for these electronic fuses are presented. A state-space based approach separates nonlinear system dynamics into multiple linear conduction modes. This method allows a resource-saving calculation of stress on electronic components, analyses of sensitivities and novel trigger mechanisms. The introduced multi stage first order model of the electronic fuse achieves a deviation of less than 5 % compared to the validated exponential first order fuse model. The method is verified by means of three state-of-the-art protection circuits.