Modelling and Control of Fast-Switching Solenoid Direct Injection Valves Using a New Magnetics Library

Abstract

This paper deals with the special challenges in modelling and controlling fast-switching solenoid valves with Modelica. For this, a solenoid injector for application in direct injection combustion engines with switching times around 100 µs is being used as an example. The occurring eddy current losses as well as the local saturation phenomena based on magnetic field displacement require for detailed network models of the magnetic domain. Therefore, a new Modelica magnetics library based on a consistent systems modelling analogy is being proposed and implemented, which increases solvability of the injector models compared to the Modelica Standard Library. Additionally, different one-dimensional contact mechanic models for representation of the bouncing behaviour of switching-type solenoids are evaluated. The complete electro-magnetomechanical model of the injector is then used for synthesis of novel closed-loop control schemes found by model inversion and parameter optimisation.