Qualitative Analysis of Electrical Circuits for Computer-based Diagnostic Decision Tree Generation
Heiko Milde, Lothar Hotz, Jörg Kahl, Stephanie Wessel · 2003
Qualitative reasoning about fault effects in electrical circuits has reached a level of achievement which allows it to be used for real world industrial applications. Dealing with electrical circuits of forklifts, our work focuses on automated diagnostic decision tree generation grounded on model-based predictions of correct and faulty device behavior. In this paper, we discuss requirements for electrical circuit analysis arising from this task. According to these requirements, we developed a new method for Qualitative electrical Network Analysis (QNA) which is the main subject of this paper. QNA’s qualitative calculus allows reasoning about actual parameter values and deviations from reference values. The calculus is specifically designed to avoid spurious solutions. To facilitate adequate device modeling, QNA supports that electrical design experts guide the modeling process, bringing in their knowledge concerning intended device behavior and negligible physical phenomena. We successfully evaluated QNA in our application domain. 1