Renault E-TECH: Developing an advanced hybrid system from LEGO concept

  • Ahmed Ketfi-Cherif, Renault’s Mechatronics Synthesis Architect, talks through E-TECH’s second phase of development
  • From the initial LEGO model created by Nicolas Fremau, the next challenge was to transform it from concept to reality
  • Inspired by Formula One technology, the innovative powertrain includes a technical ‘dog clutch’ developed for the smoothest and refined hybrid drive
  • Watch the latest video in the E-TECH’s development here: https://youtu.be/zBKXTtTTyzU

The development of Renault’s advanced E-TECH powertrains all began with a LEGO model. The next step was how to transform the toy prototype into a real, working engine. This was the challenge facing Ahmed Ketfi-Cherif, Renault’s Mechatronics Synthesis Architect.

Ahmed was one of the people who Nicolas Fremau, designer of the initial LEGO prototype, consulted in order to bring the E-TECH hybrid powertrain – and Renault’s wider hybrid plans – to life. He said: “Going from the LEGO adventure to reality was a massive challenge. It taught me a lot.”  

Smooth operation was a priority
Ahmed, who works as a control specialist, needed to ensure that transitions between driving modes were possible with a simple ‘dog clutch’, a system normally reserved for motorsport, and that the finished product would be up to the high standard demanded by the customer.

The dog clutch system – which replaces both a sprocket and synchronising ring in a clutchless configuration – is a gearbox boasting superior efficiency due to the reduced number of components.

This particular type of ‘flat’ version works well over time and is more reliable than other types of dog clutch. However, the team needed to find a solution to make the system smoother, as the components are less likely to fit together than in alternative setups such as a ‘roof’ dog clutch.

"We're used to using dog clutches in Formula One, for a racing engine. But it was something completely new for a 'general public' engine. We had to make this simple object usable by customers," explains Ahmed Ketfi-Cherif, with a smooth and refined drive of much higher importance than winning lap times.

Cleverly adding a high-voltage starter generator
Ahmed quickly came up with the solution to ensure enhanced smoothness by adding a second electric motor, called a High-voltage Starter Generator (HSG). "Its role is to replace the synchronisers of a traditional gearbox to facilitate the clutch and therefore the gear change. By working in conjunction with the electric motor, it allows very precise regulation of the speed of rotation of the gearbox for smooth gear changes."

From this, the original LEGO model concept was updated and tested on the road. They discovered the HSG brought other benefits with immediate torque contribution smoothing acceleration at low speeds, avoiding any break in torque delivery when changing gears.

This also meant the system could operate as a series hybrid for enhanced comfort and flexibility, without the need for an excess of stored energy or a charging socket. Ahmed said: “The possibilities for use in the range were multiplied”, with both E-TECH hybrid and E-TECH plug-in hybrid powertrains now possible.

At the end of these tests, the E-TECH development teams were reassured that what had worked in the LEGO concept and in simulation also worked “extremely well” in real life.

Watch the full video on second instalment of the E-TECH story here: https://youtu.be/zBKXTtTTyzU

ENDS

About Groupe Renault

Renault, a historic mobility brand and pioneer of electric vehicles in Europe, has always developed innovative vehicles. With the ‘Renaulution’ strategic plan, Renault has embarked on an ambitious, value-generating transformation moving towards a more competitive, balanced and electrified range. Its ambition is to embody modernity and innovation in technology, energy and mobility services in the automotive industry and beyond.

For further information, please visit www.press.renault.co.uk or @RenaultUKPR or contact:

Lauren Prema
Press Relations Manager
lauren.prema@renault.co.uk – 01923 697203 – 07741 233530

Charlie Roper
Brand Affairs Manager
charlie.roper-extern@renault.co.uk – 01923 697778 – 07816 641843

Yasmin Rhodes
Press Officer
yasmin.rhodes@renault.co.uk – 01923 697289 – 07385 398222

Gemma Croft 
Press Fleet Manager
gemma.croft-extern@renault.co.uk – 01923 697355 – 07887 468977

Media Usage Terms

I agree that all creative assets including but not limited to photos, logos, sketches, images and artwork are for
editorial use only. All commercial use of these creative assets, including but not limited to advertising,
marketing and merchandising, is strictly prohibited.

I agree to these terms and conditions

Images
6

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Media ID: 18872
Small 1500 x 843 0.5 MB
Medium 3500 x 1968 2.3 MB
Large 1920 x 1080 0.5 MB

© 2021 Copyright Renault. Reproduction free for editorial use only.

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Media ID: 18877
Small 1500 x 843 0.6 MB
Medium 3500 x 1968 2.7 MB
Large 1920 x 1080 0.7 MB

© 2021 Copyright Renault. Reproduction free for editorial use only.

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Media ID: 18876
Small 1500 x 843 0.4 MB
Medium 3500 x 1968 2.0 MB
Large 1920 x 1080 0.4 MB

© 2021 Copyright Renault. Reproduction free for editorial use only.

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Media ID: 18875
Small 1500 x 843 0.7 MB
Medium 3500 x 1968 2.9 MB
Large 1920 x 1080 0.8 MB

© 2021 Copyright Renault. Reproduction free for editorial use only.

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Media ID: 18874
Small 1500 x 843 0.5 MB
Medium 3500 x 1968 2.3 MB
Large 1920 x 1080 0.5 MB

© 2021 Copyright Renault. Reproduction free for editorial use only.

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Renault E-TECH: Developing an advanced hybrid system from LEGO concept

Media ID: 18873
Small 1500 x 843 0.6 MB
Medium 3500 x 1968 2.5 MB
Large 1920 x 1080 0.6 MB

© 2021 Copyright Renault. Reproduction free for editorial use only.