@techreport{R-94-40, TITLE = {Conceptual Modelling of Hybrid Systems}, AUTHOR = {Jan-Erik Str{\"o}mberg and Ulf S{\"o}derman and Jan Top}, YEAR = {1994}, NUMBER = {R-94-40}, INSTITUTION = ida, ADDRESS = idaaddr, ABSTRACTURL = {/publications/cgi-bin/tr-fetch.pl?r-94-40+abstr}, ABSTRACT = {For continuous physical systems there are many powerful methods for modelling, one of them being the conceptual modelling technique as supported by the bond graph language. However, when dealing with systems undergoing abrupt behavioural changes, i.e. mode switching or hybrid systems, the picture is quite different. The reason for this is that mode switching traditionally is treated by means of mathematical and logical concepts only instead of by more physically oriented concepts. This implies adhoc constructs and limited possibilities for automation. It is our claim that a proper concept at the physical level effectively can eliminate this modelling bottleneck. We present several arguments supporting this view, and present our solution: the ideal switch concept. An example is provided to show its practical application}, IDANR = {LiTH-IDA-R-94-40}, NOTE = {Accepted to The European Simulation Conference ESM'94 Barcelona, Spain, June 1994}