A Scroll Compressor with a High Performance Induction Motor Drive for the Air Management of a PEMFC System for Automotive Applications

This paper proposes a technological solution with a scroll compressor driven by a high performance induction machine drive for the air management of PEMFC (proton exchange membrane fuel cells) for automotive applications. The torque-speed characteristics of a real scroll compressor have been measured and then emulated by a brushless IMPM (internal mounted permanent magnets) machine controlled in torque. This emulated scroll compressor has been driven by a field oriented controlled (FOC) induction motor drive. The whole car model as well as the PEMFC have been implemented by software on the same DSP which implements the drive control algorithm; in this way the hardware-in-the-loop structure has been employed for emulating the behaviour of a real car including the electrical supply of the PEMFC. The whole system has been tested with a classic European driving cycle. Two experimental rigs have been setup, one for characterizing the scroll compressor and the other for emulating the entire vehicle. The experimental results have shown that the speed reference profile, obtained during a urban driving cycle, is followed correctly and that the tank-to-wheel efficiency remains at quite high values confirming the goodness of the proposed technological solution. The hardware-in-the-loop approach of the experimental rig allows tests to be performed to verify the operation in steady and transient states with low cost and reduced employment of the Fuel Cell stack, with resulting increased durability.