Re-Compression System for SOFC Hybrid Plants: Tests With an Emulator Rig

This paper presents a new approach to increase compressor outlet pressure in SOFC based hybrid systems. Essential solution to ensure an increase in system performance (plants equipped with a cathodic re-circulation) or SOFC efficiency. An emulator rig designed to perform tests on SOFC hybrid systems was considered to analyze three different configurations. This is an experimental plant based on the coupling of a microturbine with a modular vessel necessary to emulate the stack cathodic volume. Attention was focused on a re-compressor powered by a gas turbine (turbocharger) for simplicity and low cost performance. In this paper attention is focused on the rig modifications necessary to operate tests on the turbocharger based configuration. Even if this is a worldwide innovative solution, results showed the coupling feasibility of these machines preventing surge risks. Special attention has to be devoted on the turbocharger start-up considering the dynamic different aspects of the two machines.