A Real-Time Spatial SOFC Model for Hardware-Based Simulation of Hybrid Systems

Solid oxide fuel cell (SOFC)/ gas turbine (GT) hybrid systems possess the capability to nearly double the efficiency of standard coal-fired power plants which are currently being used for large scale power production. For the purposes of investigating and developing this technology, a SOFC/GT hybrid test facility was developed at the U.S. DOE National Energy Technology Laboratory (NETL) in Morgantown, WV as part of the Hybrid Performance (HyPer) project. The HyPer facility utilizes hardware-in-the-loop technology to simulate coupled SOFC operation with gas turbine hardware in a hybrid arrangement. This paper describes and demonstrates the capabilities of the one-dimensional, real-time operating SOFC model that has been developed and successfully integrated into the HyPer facility. The model presented is designed to characterize SOFC operation over a broad and extensive operating range including inert heating and cooling, standard “on-design” conditions and extreme off-design conditions. The model receives dynamic, system-dependent modeling inputs from facility hardware and calculates a comprehensive set of SOFC operational responses, thus simulating SOFC operation while coupled with a gas turbine. In addition to characterizing SOFC operation, the model also drives the only heat source in the facility to represent fuel cell subsystem release of thermal effluent to the turbine subsystem. Operating parameters such as solid and oxidant stream temperatures, fuel stream compositions, current density, Nernst potential and polarization losses are produced by the model in spatiotemporal manner. The capability of the model to characterize SOFC operation, within dynamic hybrid system feedback, through inert heat up and a step change in load is presented and analyzed.