Joachim Fröschl

Modeling of the automotive 14 V power net for voltage stability analysis

The number of electrical components in cars has steadily increased in recent years. Furthermore, systems with high peak loads like engine-start-stop systems and x-by-wire systems will be employed in the near future. These peak loads lead to voltage fluctuations within the power net. To guarantee the proper functioning of all electrical components, a stable voltage supply is necessary. This paper describes the modeling of the automotive power net with emphasis on the wiring harness and the chassis ground and the electrical phenomena, which must be taken into account in a voltage stability analysis of the automotive power net, are discussed. A comparison of simulations and experimental results is used to validate the derived models.

A model for sequence based power management in cyber physical systems

This paper develops a model for operating system level power management in cyber physical systems. The core part is a transducing mechanism, forming physical inputs into functional state sequences. Each functional state transition then is allowed to switch in between power management plans. A power management plan is modeled as a directed graph over power states and functional jobs together with timing conditions. Different optimization problems for designing these plans according to scheduling requirements, and for maximizing energy savings under both constrained management complexity and constrained supply voltage stability are presented.

An architecture for power management in automotive systems

This paper presents an architectural model for power management in automotive systems. It is based on recent advances in cyber physical and cybernetic control systems. Based upon a previous model of power management, formal interactions in between a hierarchical structure are characterized. In the architecture, strategic decisions allow coordinated adjusting of power management plans as well as local autonomy in subsystem scope.