DC coupled power electronics system for a fuel cell power system

摘要

An electric system 100 has a fuel cell 110 and a turbine generator 118 for a large-scale fuel cell power plant to provide power to a power grid 104. The turbine generator 118 may be driven by unused oxidant and fuel from the fuel cell 110. The fuel cell 110 output is coupled to a main ac bus 102 via a fuel cell dc bus 112 and a fuel cell inverter 114. The turbine generator output is coupled to the fuel cell dc bus 112 via a machine inverter 122, and may supply to or draw from the fuel cell dc bus 112 depending on whether it is in generating or motoring mode. A load bank 116, backup generator 124, and uninterruptible power supply 128 are also coupled to the main ac bus 102, and the main ac bus 102 supplies the power grid 104. Methods of operating the system 100 under various conditions are disclosed. Also disclosed is an electric system (1000, figure 10) in which the turbine generator output is coupled to the main ac bus (1002) via a machine inverter (1022) and grid inverter (1024), and a turbine generator load bank (1026) draws power from the turbine generator (1018).