A Single-Phase Grid-Connected Fuel Cell System Based on a Boost-Inverter

The boost-inverter topology is used as a building block for a single-phase grid connected fuel cell (FC) system, which is offering low cost and compactness. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied. In order to the meet the system operational and security requirements, fuel cell power systems need to be interfaced with the utility grid connected through a set of power electronic devices. Interconnecting a fuel cell power system with a utility grid is very important since the interface will not only affect the fuel cell system, but also the grid connected. In addition to that, the proposed system incorporates battery-based energy storage and a dc–dc bidirectional converter (Back-up unit) to support the slow dynamics of the FC. The single-phase boost inverter is voltage-mode controlled and the dc–dc bidirectional converter is current-mode controlled. The low-frequency current ripple is supplied by the battery which minimizes the effects of such ripple being drawn directly from the FC itself. Moreover, this system can operate either in a grid-connected or stand-alone mode. In the grid-connected mode, the boost inverter is able to control the active (P) and reactive (Q) powers using an algorithm based on a second-order generalized integrator which provides a fast signal conditioning for single-phase systems. A Simulink based model is developed and the simulation results for the proposed model applied to induction motor drive by using MAT LAB