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The goal of this paper is to provide a basis for the analysis of the limits of the reconstructability of current densities from their magnetic fields as used for non-destructive testing and monitoring of fuel cells. For the reconstruction of a current density from its magnetic field, we study the properties of the Biot-Savart operator W . In particular, the nullspace N(W ) of the Biot-Savart operator and its orthogonal space N(W ) ⊥ with respect to the L 2 scalar product are characterized. The characterization of these spaces is a basic step for the evaluation of the principal limits of magnetic tomography for fuel cells and for the development of efficient reconstruction algorithms. Further, practically realizable examples for elements in the nullspace N(W ) are provided. Finally, for a discrete wire network we show uniqueness for current reconstructions, i.e. the result N(W ) = {0}.

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This is the third paper of a three part series on fuel cell vehicle (FCV) simulation. In Part 1 of this series, the existing publicly available models for FCV analysis and simulation were evaluated and the strengths and weaknesses of these models were identified. In Part 2, a new FCV simulation framework (and the methodology behind it) was introduced which focused on overcoming the weaknesses of the benchmarked models. In this third paper, the model framework developed in Part 2 is filled with component models. Specifically, models for the electric drive train, the transmission, a battery system, a dc‐dc‐converter and a fuel cell system with the associated control units are developed and described. An indirect‐methanol fuel cell system, with all of its subsystems, is illustrated in this paper, as an example of the process and implementation of a fuel cell system model. This example fuel cell system is characterised in both steady‐state and dynamic terms by numerical simulation, and is also used to illustrate the system integration required for a complete FCV simulation model.

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