Interpolation technique for effective determination of switching time instants for field-circuit coupled problems with switching elements

摘要

Purpose - To provide a numerical technique for the quick and simple determination of the switching time instants for field-circuit coupled problems with switching elements. Design/methodology/approach - 3D magnetic vector potential formulation coupled to an electrical circuit with switching elements, for example, diodes, is presented. The change of the state of the switching elements is implemented as a modification of the model topology. Findings - Since every step of the singly diagonally implicit Runge-Kutta methods delivers not only the solution of this time step but also its stage derivatives, they can be efficiently employed to construct a dense-output-based interpolation polynomial, with their roots approximating the switching time instants. Originality/value - This paper presents a computationally cheap interpolation approach for quick and accurate determination of switching time instances for field-circuit coupled problems with switching elements. The proposed technique can be successfully incorporated into software packages designed to model coupled problems of different nature, where sudden changes of quality may take place.