Garrett Readies e-Turbo

Switzerland-based Garrett Motion Inc., which was spun off from Honeywell International Inc. last year, plans to launch an electric turbocharger in production vehicles in 2021.

The initial application will be in a high-performance car. Garrett says it also has 10 other development programs for a variety of different types of vehicles.

Several carmakers—including Audi and Mercedes-Benz—already offer electrified turbochargers. Those systems behave like an electric supercharger, with the electric unit providing low-end boost to minimize turbo lag until the main exhaust-driven turbocharger takes over.

Garrett’s integrated system, which includes new software algorithms, adds a small electric motor on the shaft between the turbine wheel and the compressor. This enables the turbo to quickly spool up and provide nearly instantaneous boost.

Other purported benefits include improved packaging and the flexibility to use a larger turbocharger to better match an engine’s operating “sweet spot.” Garrett notes that the size of conventional turbochargers are constrained by tradeoffs that prioritize efficiency at low engine speeds.

Garrett says its e-turbo system also can be used to help hybrid-electric vehicles recapture lost exhaust energy. In these applications, the small motor would generate electricity to recharge the hybrid battery and reduce the load on the alternator.

In recent tests, Garrett’s e-turbo provided a 16% increase in horsepower and 10% more torque than the company’s conventional turbocharger. The electric unit also achieved low-end (1,500 rpm) torque nearly 80% faster and reduced 60 kph to 100 kph (37-63 mph) acceleration times by as much as 25%, according to the supplier.