What is BMW eBoost?

Automakers spend billions of dollars on research and development in an endless quest to make internal combustion engines (ICEs) more useful and efficient. Sometimes that expense translates into a giant breakthrough, like the electric self-starter developed over 100 years ago. But more often than not, that translates into small but significant gains, which is the case with BMW’s eBoost.

Those who follow automotive technology understand that “e” most often refers to some form of electrification. At the same time, “boost” generally refers to something that momentarily increases performance. This is for example the case of the “boost” obtained thanks to turbocompression or supercharging. Based on this context, it’s no surprise that BMW eBoost refers to a method of improving vehicle performance by adding a relatively short-lived “burst” of electric power.

To understand BMW eBoost, it is instructive to understand the concept commonly referred to as “mild hybrid”. In automotive terms, a powertrain with mild-hybrid technology operates in most cases like a conventional gasoline or diesel vehicle, but derives additional power in specific cases from a relatively small, low-power electric motor.

Of course, all modern ICEs use an electric motor to start. This century-old innovation made ICE cars practical for wide use in the first place. Since all ICE vehicles are equipped with starter motors, it is not too difficult to use this motor to add horsepower and torque in specific cases.

Early vehicles with mild-hybrid technology used the standard 12-volt electrical system that has been the industry standard since the 1950s and typically used a somewhat more heavy-duty starter to add small amounts of power in vehicle-specific situations. short term like accelerating from a stop. This offered some advantages, but the small 12-volt motor limited the added power (“boost”).

BMW and other European automakers led the way by developing 48-volt electrical systems that had the advantage of offering more power. This allows them to not only provide extra acceleration, but also faster starting in the nearly ubiquitous automatic engine stop/start systems that ICE vehicles use today.

Two sources send energy to the on-board storage battery in the BMW mild hybrid system. The starter alternator creates electricity during normal vehicle operation. Regenerative braking captures the extra energy when the vehicle brakes (decelerates). A regenerative braking system generates electricity and injects it into the vehicle’s 48-volt battery.

BMW eBoost

BMW eBoost most often refers to the use of electric motor power and torque to improve performance and reduce fuel consumption and carbon dioxide emissions. Electric starter motor-generator power/torque is used when added power is beneficial, such as acceleration from a stop, gear changes, and hard acceleration. The last of them might have required a quick downshift without the ability to add power from the electric motor. In an engine equipped with a turbocharger, the eBoost can bring power into what would previously have been a “turbo lag” period.

The eBoost system is efficient because an electric motor delivers its maximum torque from virtually zero revolutions per minute (rpm). And it’s effective because regenerative braking recovers a lot of the electricity, energy that would otherwise be wasted. Using eBoost also allows the engine stop/start system to stop the engine quieter and restart it faster and easier.

BMW is constantly improving its mild-hybrid technology, although it is increasingly emphasizing battery-electric vehicles. In fact, continuous improvements in battery and electric motor technology are also enabling advances in mild-hybrid technology.

The current BMW 3 Series is an example of BMW eBoost technology and mild hybrid technology in its most advanced form. The M340i’s 3.0-litre inline 6-cylinder engine demonstrates the simultaneous optimization of power and efficiency enabled by technology. The 48-volt generator-starter functions as a second drive unit that assists the gasoline engine in certain situations, allowing it to operate in its most efficient load range. When the driver requests additional power, the BMW eBoost in the starter-alternator steps in to provide it. This can happen when accelerating from a traffic light or when passing at highway speeds on the freeway.

Several elements improve efficiency. First, since immediate torque is available from the electric motor, engineers can calibrate the gasoline engine to operate in a more efficient range. At the same time, the 3 Series uses electricity generated by braking and stored in the 48-volt battery to power the vehicle’s 12-volt electrical system.

In the broadest sense, an automaker could apply eBoost to any situation where they need to use the power of an electric motor to improve performance or efficiency. Therefore, one could also consider the application of electric power in a more sophisticated hybrid powertrain (such as a plug-in hybrid) as eBoost. Sometimes BMW differentiates between eBoost and something it calls Xtraboost, but the distinctions are nebulous. The key thing to know is that BMW eBoost improves both performance and efficiency. And it does so without adding the extreme complication of a more elaborate hybrid system.

For more help in making good buying decisions, visit the Buying Guides section of the website.

#BMW #eBoost

Add Comment