Multiphysics Transients Modeling of Solid Oxide Fuel Cells: Methodology of Circuit Equivalents and Use in EMTP-Type Power System Simulation

Programs of the Electromagnetic Transients Program (EMTP) type have been the most popular digital simulators for emulating electromagnetic transients in power electric networks consisting mainly of rotating machinery, lines, transformers, loads, and power electronic converters. With the increasing interest in fuel cells, it would be beneficial to extend the scope of EMTP-type application to multiphysics transients as they appear, for example, in fuel cells. The concept and realization of this extension are presented in this paper. Analogies between electric, pneumatic, and thermal quantities are exploited for developing circuit models that describe currents and voltages, molar flows and pressures, and heat transfers and temperatures. It is shown how already existing libraries of network components of typical EMTP-type simulators accurately emulate the involved multiphysics phenomena of multiple energy carriers. The theoretical considerations are complemented by validation and application to combined heat and power to illustrate the value of the modeling. The studies are conducted using the program PSCAD as an example of the EMTP-type family and center on the solid oxide fuel cell.