Several attempts have been made in recent years to achieve a practical e-boosting system.

In order to produce a full range gasoline boosting system a supercharging load of around 10% of peak power is typically required making pure e-boosting solutions currently unattractive for this purpose. Our SuperGen technology uses a parallel hybridisation approach to mitigate this reducing the electrical power requirement by a factor of around five.

As more engines become available with twin variable cam phasers IP has also been re-evaluating how this may enable a cost-effective e-boosting system operating at low speed as part of a downsizing / down speeding strategy for CO2 reduction.

During SuperGen related investigations it was found that, when used together with variable camshaft phasing and suitable engine geometry, a disproportionate advantage can be gained at low engine speed for a relatively low level of boost.

This is because by providing a positive pressure difference between inlet and exhaust, a controlled scavenging event can be produced during valve overlap improving charge purity and volumetric efficiency even with a close-coupled catalyst. This is in contrast to the disappointing results produced at low engine speed when variable camshaft phasing is employed with a close-coupled catalyst.

We are currently investigating the feasibility of a 500W system applied to a small 4cyl engine. This rating enables continuous operation even with a low cost electrical architecture using a conventional alternator.

If interest proves to be sufficient, results can realistically verified by customer engines using one of our SuperGen prototypes prior to detailed engineering of a practical system.