Modellgestützte Regelung von Stauhaltungssystemen und Laufwasserkraftanlagen
Depending on its hydraulic characteristics the control of run-of-river-hydro-schemes sets high standards to the operator of these systems. The main reasons are strong nonlinear properties of the fundamental hydrodynamic process with its large and variable dead time between a change of inflow into the system and a change of the controlled water level at the other end of the hydro scheme. If in addition the water level has to be kept within a tight tolerance band conventional governors regularly fail to guarantee a reliable operation within the set limits. Based on this experience operators frequently call for a model based control of theses hydro schemes similar to process control applications in the chemical and petrochemical industry, particularly because there is hardly any hardware difference between model based and conventional process control systems today. Model based governors promise to show a better control of nonlinear processes due to their built in process knowledge. They are not limited to a single design point like conventional PI-controllers but offer a wide process range. Unfortunately no methods have been published so far to develop model based controllers for the hydro business and to specify its abilities. In order to obtain results about the control quality of conventional and modern approaches this thesis analyzes a variety of both kinds of control methods in their general suitability as far as their weaks and strengths. In this context some new aspects arise even for the definition of regulation parameters and boundary conditions for the design of conventional governing concepts. For the reliable control of ambitious hydro schemes especially when combined with high demands in process quality only MPCs (Model Predictive Control) show to be sophisticated enough to deal with these conditions. Core element of a model-integrated regulation is an appropriate hydro-dynamic simulation model. Usually a one dimensional simulation should be sufficient. As suitable simulation methods for integration into a regulation concept characteristic procedures, finite difference methods and finite volume models are determined. This thesis continues with an evaluation of structure and variants of a MPC concept and defines boundary conditions to be considered. The theoretical approach is confirmed by the discussion of characteristic applications on the basis of hydrodynamic simulations. These simulations show in an impressing way the attainable efficiency and quality of a MPC concept, especially compared with conventional governing methods. MPCs have not been used for real hydro control yet. Therefore additional comments and relevant information are given for a practical implementation in future.
info:eu-repo/classification/ddc/620, Laufwasserkraftwerk, Wasserstand, Abfluss, Prozessmodell, Prädiktive Regelung, Stauanlage, Fließgewässer, Ingenieurwissenschaften, Wasserkraft, Stauhaltung, Modell, Regelung, MPC, prädiktiv, Qualität, Gerinne
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