The applicability of online total harmonic distortion analysis (THDA) for the operation and monitoring of solid oxide fuel cell (SOFC) power systems is investigated by experiments as well as analysis of the algorithm, with a focus on the relationship between stack fuel utilization rate and the corresponding THD index. An online THDA algorithm is implemented in a programmable logic controller (PLC) and operated with a 6 kW SOFC power system demonstration unit. Laboratory experiments on the solid oxide fuel cell technology are carried out to determine key parameters for the algorithm. The embedded implementation of the THDA algorithm, including several modifications to reduce its computational load, and its parameterization is analyzed and the program code is given in the Appendix. The experimental results verify that THDA can be a reliable means for quantitatively monitoring the fuel utilization rate experienced by the stack and that the algorithm is simple to implement on an embedded controller.
- Fuel Cell Stack Monitoring
- Fuel Cells
- Solid Oxide Fuel Cells
- Total Harmonic Distortion Analysis