PSEUDO BOND GRAPH SYSTEM MODELLING OF ELECTRIC AIR COMPRESSORS WITH ENERGY RECOVERY FOR FUEL CELL APPLICATIONS

摘要

In this paper, the novel machine type of an electric air compressor (EAC) for fuel cell applications is investigated and simulated using a Pseudo Bond Graph (PBG) approach. Initially, the system along with its miscellaenous components is derived in the Pseudo Bond Graph notation. Subsequently, the multiphysical connections of fluid, thermal and electrical domains are highlighted. In addition, a derivation for an extended definition of the Pseudo Bond Graph theory's inertia I element is presented. In contrast to the previous formulation, it takes into account the effects of compressibility which were previously neglected. The simulations are carried out using in-house simulation tool ASTOR (AircraftEngine Simulation for Transient Operation Research) and feature different transient acceleration and deceleration manoeuvres with varying manoeuvre duration. It is shown that manoeuvre duration significantly influences transient performance such as the surge margin which is found to decrease by up to 9 % in comparison to the steady operating line. In addition, deceleration is identified as the most critical operating condition.