Dynamisk modellering av energisystem

Abstract

This master thesis has been done at Solvina AB in Vastra Frolunda. The purpose of this thesis is to develop a model library called SteamPower, which consists of steam/water energy system components. The library is for use in dynamic simulation in the Modelica/Dymola environment. Modelica is an object-oriented programming language that is mainly focused on simulations of physical systems. Dymola is a QUI for Modelica that can be used both as an editor and simulator. The main objective has been to develop an efficient, well-documented and userfriendly library. Focus has been on developing accurate models of valves and a turbine. In developing the SteamPower models there has been a need to verify them against measured data, which has been done continuously against data from a pulp mill in Sweden. Also the need to test the components in a complex dynamic environment has been crucial for developing stable and well-performing models. Therefore a quite complex model of a pulp mill was developed and used for simulation tests. During the development and testing phase a number of numerical problems were discovered and they had to be addressed in order to have stable performance. The models developed have been verified against different sources and they show a behavior that is acceptable for the designed purposes.