| 1. |
- Edström, Krister, et al.
(författare)
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Aspects on Simulation of Switched Bond Graphs
- 1996
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Ingår i: Proceedings of the 35th IEEE Conference on Decision and Control. - Linköping : Linköping University Electronic Press. - 0780335902 ; , s. 2642-2647 vol.3
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- By mode-switching systems we mean physical systems characterized by transitions which are at least an order of magnitude faster than the overall time-scale. There are essentially two different ways to model such systems for simulation. One is to employ continuous models and stiff solvers. This approach is becoming more feasible as more sophisticated stiff solvers become available, but still suffers from poor performance for larger models. An alternative approach is to employ hybrid models with instantaneous transitions between continuous mode-model, In this case solvers capable of detecting zero-crossings are required. The advantage of this approach is an improved simulation performance but the disadvantage is that one has to deal with more complex models. To handle the model complexity matter we have previously proposed switched bond graphs as a solution. Employing switched bond graphs, the problem of complex models is modified to the problem of translating the bond graph to a computational model. This is the problem addressed here.
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| 2. |
- Edström, Krister, et al.
(författare)
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Modelling and Simulation of a Switched Power Converter
- 1996
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In our earlier work dealing with switched systems we have focused on the conceptual and formal side of the modelling process. In this paper we go one step further and illustrate the practical generation of simulation code from a switched bond graph. The principles are illustrated by means of an industrial switched power converter used to control the power of electric rotary machines. We describe an implementation of the formal Mode Transition System (MTS) presented earlier. The format proposed is referred to as Mode Transition File (MTF) format. We present an algorithm to generate the mode transition file from a switched bond graph. Finally we illustrate how this file format can be converted to code for the well known DASSRT solver.
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| 3. |
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| 4. |
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| 5. |
- Strömberg, Jan-Erik, et al.
(författare)
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Modelling and Simulation of a Switched Power Converter
- 1997
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Ingår i: Proceedings of the Third International Conference on Bond Graph Modeling and Simulation. - 1565551036 ; , s. 195-200
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Konferensbidrag (refereegranskat)abstract
- In our earlier work dealing with switched systems we have focused on the conceptual and formal side of the modelling process. In this paper we go one step further and illustrate the practical generation of simulation code from a switched bond graph. The principles are illustrated by means of an industrial switched power converter used to control the power of electric rotary machines. We describe an implementation of the formal Mode Transition System (MTS) presented earlier. The format proposed is referred to as Mode Transition File (MTF) format. We present an algorithm to generate the mode transition file from a switched bond graph. Finally we illustrate how this file format can be converted to code for the well known DASSRT solver.
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| 6. |
- Strömberg, Jan-Erik, et al.
(författare)
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Modelling and Simulation of Hybrid Systems
- 1996
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Ingår i: Proceedings of Reglermöte 1996. - Linköping : Linköping University Electronic Press. ; , s. 185--190
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 7. |
- Söderman, Ulf, et al.
(författare)
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Mode Invariant Modelling
- 1995
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Modelling of physical systems is a difficult task, in particular if mode switching is allowed. Automated support can be supplied, if two conditions are fulfilled. First, a set of suitable qualitative concepts has to be availiable as a tool box for constructing adequate models. Second, powerful computational machinery must handle model complexity. In this paper we introduce both a conceptual basis and a computational algorithm for dealing with mode switching physical systems. Our approach is more effective than current AIbased methods since it is based on general physical principles at the proper level of abstraction, expressed in terms of bond graphs. The latter formalism is extended in order to deal with mode switching. All meaningful causal modes and transitions between modes are derived automatically. A power electronic circuit serves a guiding example.
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| 8. |
- Söderman, Ulf, et al.
(författare)
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Switched Bond Graphs : Towards Systematic Composition of Computational Models
- 1995
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Ingår i: Proceedings of the 2nd International Conference on Bond Graph Modeling and Simulation. - Linköping : Linköping University. ; , s. 73-79
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In classical bond graph modelling, a computational model is systematically composed from the parts without having to introduce local or global patches. Unfortunately this has not yet been fully carried over to switched bond graphs, i.e. bond graphs employing the ideal switch concept. The focus of this paper is on the systematic composition of the discrete mode transitions. To this end we provide a mathematical structure for the composed computational model and a procedural composition operator. We also outline an algorithm to localize and adjust the composed system in those cases where the composition operator fails. An important concept in this treatment is the generalization of primitive switches to multiport switch fields.
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