Electromagnetics - Modelling, Simulation, Control and Industrial Applications - Abstract
Stingelin, Simon
Electromagnetic flow measurement has been in use around the world for more than 50 years, as witnessed by the popularity of these meters that continues unabated in virtually all sectors of industry. Electromagnetic flowmeters can be used to measure all electrically conductive liquids ($>!!5 mutextS/cm$) with or without solids, e.g. water, wastewater, slurries, pastes, juices, etc. The volume flow measurement is performed differentially with a pulsed magnetic field to suppress noise voltages as efficiently as possible. The key question in the talk is: How should the coil voltage be controlled to switch as fast as possible from one field state to another? Because we want to control the voltage in a induction coil, this question leads us to the optimal control of an eddy current problem coupled with an ordinary differential equation for the electrical current. The ordinary differential equation is derived from the induction law. In the talk we present the necessary first order optimality conditions of the control system and mention the well-posedness. Then we discuss numerical methods used to calculate the optimal coil voltage. Finally we present computations based on industrial flow meter geometries.