UK-based technology innovation company Aeristech has developed what it claims is the first electric supercharger capable of continuous operation at high boost levels.
The company says that the system has been independently validated by Ricardo and Mahle Powertrain, including a demonstration of the technology by Mahle in a mid-size appraisal vehicle using its downsized 1.2-liter three-cylinder gasoline engine, which achieved 33 bar BMEP at 2000rpm (313Nm for an engine of this capacity) and a maximum power output of 262ps.
Aeristech says that it has got over thermal management issues associated with other electric boosting devices on the market by using permanent magnet motor technology instead of the switched reluctance type. The e-machine design means lower inertia, and the e-supercharger operates at up to 150,000rpm with a transient response of idle-to-target speed in under 0.4 seconds.
“Our system can deliver over 2.5 bar of boost pressure continuously, setting it apart from other systems which only offer short duration boost assist for improving the engine transient response,” said Aeristech CEO Bryn Richards. “By using a 48V architecture, we have provided a solution that is easily implemented and competitive in cost for the growing numbers of hybrid and mild-hybrid vehicles that will be launched in the next few years.”
Ricardo tested out the new system using WAVE simulation, carrying out modelling of a 300ps 2-liter gasoline engine with a single-stage turbocharger. Adding the 48V Aeristech electric supercharger enabled the turbine to be increased in size by 80%, says the company, improving BSFC (brake specific fuel consumption), torque and transient response throughout the engine speed range. Ricardo concluded that without the eSupercharger only a larger engine could have met the requirements, if relying on a conventional single-stage turbocharger.
August 3, 2015