Investigation on the Performance of a Mechanistic Electric Turbocharger Model for a Vehicular Fuel Cell System 2011-01-1742

The electric turbocharger is a promising type of air supply unit for future automotive fuel cell drive systems. It comprises of a centrifugal compressor, a variable geometry turbine and a permanent magnet synchronous motor assembled on a single shaft. Compared to other types of vehicular fuel cell air supplies, like for example a screw or roots compressor, it needs less installation space and has lower weight while also causing less noise and vibration. This paper presents a validated mechanistic model of the electric turbocharger. The stationary compressor model is based on a set of aerodynamic loss models with surge and stone wall line prediction capability. Similarly, the stationary variable axial turbine is a detailed station based model derived from aerodynamic losses at the turbine wheel and the stator blades. The aerodynamic losses incorporated in the compressor and the turbine models are implemented under MATLAB/Simulink and show a good correlation with the experimental data. Finally, the validated models of the two turbo-machines are completed by a dynamic physical model of a permanent magnet synchronous machine to form an electric turbocharger. The data obtained by this method can immediately be used for creating interpolating tables or neural networks in order to perform real time simulations on fuel cell system or even power train level.