Akshath K.M

1st Sem M.Tech

Automotive Technology

PES University

Bangalore

Energy Recovery System In Formula 1

@7urboCharger

• Formula 1 – the pinnacle of motorsport itself. - a racing series that has

always believed in technological advancements and development of the

racecar, often despite road blocks from critics, press, experts and the

FIA.

• In the quest for every tenth of a second, each time a manufacturer has

come up with a piece of engineering that would give its car an edge, the

FIA has come down hard banning or imposing strict limitations on its

future implementations in the sport.

• The FIA has decided to try and take Formula One in a more

environmentally friendly direction. As a result of this, the FIA feels that

Formula One cars should more closely resemble hybrid cars available

on the consumer market.

• Because this is the direction that production cars are moving with a

concern over environmental impacts and energy efficiency.

Introduction

• In addition to the hybrid technology, the FIA has placed a 100 kg per race

fuel cap. These factors have driven the new engines to move from V8’s

to V6’s, and necessitate a vastly important ERS (Energy Recovery

System).

• Long-time fans of Formula One racing will be familiar with the concept

of a Kinetic Energy Recovery System (KERS), technology that was

introduced to the sport in 2009 and was a mainstay from 2011.

• KERS worked by harnessing waste energy created under braking and

transforming it into electrical energy, providing an additional 60kW

(approximately 80bhp) of power for up to 6.67 seconds per lap.

• The Energy Recovery Systems (ERS) which form an integral part of an

F1 car’s power unit from 2014 take the concept of KERS to another

level, combining twice the power with a performance effect around ten

times greater.

Formula 1 Power Unit

• The engineers no longer refer to thenext generation of F1 powertrain as“engines”. They are now dubbed as“power units”.

• The reason behind this being that thepowertrain is made up of more thanjust a combustion engine/turbo, thereare more complex elements involved.

• The recovery systems on board willgenerate enough energy to supplyplenty of extra kick via an electricmotor, with the additional poweroutput mapped into the enginesystem to provide more performanceat optimal stages of the lap (i.e. thedriver will no longer have to push abutton to use the additional poweravailable).

2014 Renault Sport F1 V6 Power Unit

Elements of a Formula 1 Power Unit

The power unit is now defined by 6 essential

elements:

1. The engine – V6, turbocharged

2. The turbocharger – single stage compressor and turbine

3. The Motor Generator Unit-Kinetic (MGU-K) or basically the KERS

4. The Motor Generator Unit-Heat (MGU-H)

5. The Energy Store, ES (battery)

6. The Motor Generator Unit control electronics, MGU.

Of the above, the last four form the basis of the ERS.

Energy Recovery System - ERS

ERS comprise two energy recovery systems, Motor Generator Unit - Kinetic[MGU-K] and Motor Generator Unit - Heat [MGU-H], plus an Energy Store(ES) and control electronics.

Motor Generator Unit - Kinetic [MGU-K]

• The MGU-K harvests energy during braking or deceleration, using the crankshaft ofthe ICE to turn the shaft of the MGU-K.

• During acceleration, the MGU-K draws stored energy from the battery system toturn the crankshaft of the ICE at a peak of 120 kW, at an overall lap maximum of 4MJ output.

• The MGU-K is an electric generator/motor that is connected directly to thecrankshaft of the engine (referred to in technical regulations as the ICE, InternalCombustion Engine).

"Magneti-Marelli Motorsport" Motor Generator Unit – Kinetic (MGU-K) with electronic control unit

Motor Generator Unit - Heat [MGU-H]

• This excess energy would normally be expelled through a waste gate, but insteadis directed into the MGU-H.

• Unlike the MGU-K which is limited to recovering 2MJ of energy per lap, the MGU-H is unlimited. MGU-H also controls the speed of the turbo, speeding it up (toprevent turbo lag) or slowing it down in place of a more traditional wastegate.

• The MGU-H works in much the same way as the MGU-K. However, it is connectedto the turbine shaft of the turbocharger, instead of directly to the ICE. The “H”(for heat), is a bit of a misnomer.

• The MGU-H does not harvest energy by the heat from the turbocharger, but bythe unused rotational energy from excess turbine speed and pressure.

• The MGU-H produces AC current, but the battery and MGU-K is DC current so a highly complex convertor is needed.

• Very high rotational speeds are a challenge as the MGU-H is coupled to a turbocharger spinning at speeds of up to 100,000rpm. Bearing design and again cooling are critical.

"Magneti-Marelli Motorsport" Motor Generator Unit – Heat (MGU-H)

The Energy Store• Heat and Kinetic Energy recovered can be consumed immediately if required, or

used to charge the Energy Store, or battery.

• The ES (Energy Storage) can hold up to 4MJ of energy which can be be utilizedeither by the MGU-H to spin the compressor (reducing lag) or by the MGU-K at arate of up to 120kw (roughly 160hp). If this 4MJ of energy were to be dispensedsolely by the MGU-K at 120kw it would equate to 33.33 seconds of peak power.

• The battery has a minimum weight of 20kg to power a motor that produces120kW. Each 1kg feeds 6kw (a huge power to weight ratio), which will producelarge electromagnetic forces. The battery is mounted behind the driver andunderneath the fuel cell.

• The electromagnetic forces can impact the accuracy of sensors, which areparticularly sensitive. Balancing the forces is like trying to carry a house ofcards in a storm – a delicate and risky operation.

• However a battery is not mandatory, indeed in 2013 one team used a systemwith both ultra capacitors and a battery to get a performance boost. In WECwhere the same rules are in force, flywheel and capacitor storage is used.Both are legal in F1.

How ERS Works?

Performance Comparisons

Conclusion

• ERS a technology for the present and the future because it’senvironment-friendly, reduces emissions, has a low production cost,increases efficiency and is highly customizable and modifiable.

• Adoption of a ERS may permit regenerative braking and enginedownsizing as a means of improving efficiency and hence reducing fuelconsumption and CO2 emissions.

• The ERS have major areas of development in power density, life,simplicity, effectiveness and first and foremost the costs of the device.

• Applications are being considered for small, mass-production passengercars, as well as luxury cars, buses and trucks.

Reference

1. Racecar-engineering.com2. Renaultsportf1.com3. Formulaspy.com4. Formula1.com5. F1technical.net6. Autosport.com7. Somersf1.blogspot.com