Garrett Electric Turbochargers Headed To Production In 2021

 

Electric motors are undoubtedly becoming a larger and more important element of the automotive propulsion landscape with each passing year. Directly supplying torque to turn the drive wheels is the most obvious use case as in hybrid and electric vehicles. But motors are turning up everywhere including oil and coolant pumps and now turbochargers. Garrett Motion is preparing for what may be the first production application of an electric turbocharger in 2021. 

Garrett, was spun off from Honeywell in late 2018, reclaiming part of the original name it had before being acquired by the same company in 2004. Garrett has been producing turbochargers since the 1950s and is one of the handful of market leaders along with BorgWarner, BMTS, IHI and Mitsubishi, all of whom are developing similar technologies. 

Let’s back up with a quick primer on engine boosting. An internal combustion engine makes power by igniting a mixture of air and fuel in the cylinders. The more air and fuel that are burned, the more power that can be produced. A naturally aspirated engine draws in air through the open valves by the partial vacuum created by the piston moving downward in the cylinder. A supercharger is a mechanically driven pump that forces more air into the cylinder. These are traditionally driven by a belt off the crankshaft. They give excellent response because of the direct drive, but consume a lot of power to be driven at higher speeds. 

A turbocharger does the same thing but it is driven by exhaust gases flowing out of the engine through a turbine. The gases spin up the turbine which sits on a the same shaft as a compressor wheel. As the turbine spins, the compressor pumps the air into the cylinders. Turbos are more efficient than superchargers thanks to lower parasitic losses but they can have lag in spinning up while they wait for exhaust pressure. That’s where adding an electric motor comes into the picture.

There are actually two distinct types of electric boosting devices for engines that have emerged in the past several years. The first type that is already in use by Volkswagen Group and Mercedes-Benz is an e-booster. This is essentially just the compressor side of the turbo paired with an electric motor. The size of the compressor is inherently limited by the size of the motor required to spin it at high speeds and e-boosters are used in a sequential combination with exhaust driven turbos. The e-booster gives quick low-end response from the motor and then as pressure builds, the larger turbo takes over to provide maximum boost.

Source:-forbes.com