Affiliations: Department of Information Technology, Lund Institute
of Technology, P.O. Box 118, 221 00 Lund, Sweden | GoalArt, Tunavägen 39C, 223 63 Lund, Sweden
Abstract: Multilevel flow modeling (MFM) is a modeling method for complex
technical systems in which the goals and functions of the system are explicitly
described. MFM can be used as a basis for root cause analysis, where primary
root causes are separated from consequential faults, in complex fault
situations. Model representations for use in diagnostic reasoning usually
describe causality, between parameters, faults, or process states. However, the
causality of a system may vary depending on details in the construction, as
well as over time with the process state. One contribution of this paper is a
general method of describing varying causality in a simple and efficient way.
The method has been tested using multilevel flow models. Causality is visible in measurements and can be used to increase
process understanding. The standard cross-correlation technique is insufficient
for causality detection in industrial processes. Another contribution of this
paper is a new method that can detect causality in industrial signals, and thus
be used to validate the design of multilevel flow models.
