Kinetic energy recovery system

A SEMINAR ON

KINETIC ENERGY RECOVERY SYSTEM (KERS)

Presented By:

Ashwini Kumar

10104EN053

Electrical Engineering Part 4

Critic:Shruti Agarwal10104EN004Electrical Engineering Part 4

WHAT IS KERS?

The acronym KERS stands for Kinetic Energy Recovery System.

Kinetic energy recovery systems (KERS) store energy when the vehicle is braking and return it when accelerating. 

During braking, energy is wasted because kinetic energy is mostly converted into heat energy or sometimes sound energy that is dissipated into the environment.

Vehicles with KERS are able to harness some of this kinetic energy and in doing so will assist in braking.

BASIC ELEMENTS OF KERS

First, a way to generate power from this breaking energy, and then return energy to the power train.

Second, a place to store this energy. Third, a control unit which manages the

entire mechanism.

WORKING PRINCIPLE

Basically, it’s working principle involves storing the energy involved with deceleration and using it for acceleration.

A standard KERS operates by a ‘charge cycle and a ‘boost cycle’.

TYPES OF KERS

There are two basic types of KERS systems: Electrical Mechanical

The main difference between them is in the way they convert the energy and how that energy is stored within the vehicle.

ELECTRICAL KERS

Components-1. Motor Generator Unit (MGU)2. Power Control Unit (PCU)3. Battery

In electrical KERS, braking rotational force is captured by an electric motor-generator unit (MGU) mounted to the engines crankshaft.

MGU (Motor-Generator Unit)

Takes the electrical energy and stores it in batteries.

Works in 2 modes. Weighs around 7-8 Kg.

PCU (Power Control Unit)

Serves 2 purposes:1. To invert and control the switching of

current between battery and MGU.2. Monitoring individual cells in battery.

As with all KERS components the PCU needs cooling.

Batteries become hot due to multiple charging-discharging in races.

Super-capacitors can also be used to store electrical energy instead of batteries; they run cooler and are debatably more efficient.

WORKING PRINCIPLE

MECHANICAL KERS

The concept of transferring the vehicle’s kinetic energy using flywheel energy storage was postulated by physicist Richard Feynman in the 1950.

Uses flywheel as the Energy Storage device.

Unlike electrical KERS, this method of storage prevents the need to transform energy from one type to another.

To cope with the continuous change in speed ratio between the flywheel and road-wheels, a continuously variable transmission (CVT) is used.

CVT to control the braking and acceleration rates.

ADVANTANGE OF MECHANICAL KERS OVER ELECTRICAL KERS

Battery-based electric hybrid systems require a number of energy conversions each with corresponding efficiency losses. On reapplication of the energy to the driveline, the global energy conversion efficiency is 31–34%.

The mechanical hybrid system storing energy mechanically in a rotating fly wheel eliminates the various energy conversions and provides a global energy conversion efficiency exceeding 70%, more than twice the efficiency of an electric system.

ADVANTAGES OF KERS

This potential advantages and features of this technology in the field of automobiles are:

High power capability High speeds attained in lesser time Overtaking and defence improved in F1 Fuel Consumption to be reduced Light weight and small size Long system life A truly green solution High efficiency storage and recovery Low embedded carbon content Low cost in volume manufacture 

DRAWBACKS OF KERS

Storage capability Weight, particularly important in F1 cars Explosion in batteries Electric shocks Incidents regarding gearbox locking Teams not ready to spend millions for

developing the technology

CONCLUSION

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

Adoption of a KERS may permit regenerative braking and engine downsizing as a means of improving efficiency and hence reducing fuel consumption and CO2 emissions.

The KERS has 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 passenger cars, as well as luxury cars, buses and trucks.

It is the need of the hour, as we want to bring back the engineering part in Formula 1.

Hope it can be brought to roads, with the continuously increasing fuel costs.

Will be particularly useful in urban areas, where breaking is more frequent.

REFERENCES

http://f1.wikia.com/wiki/Kinetic_Energy_Recovery_System Kinetic Energy Recovery Systems for Racing Cars, byAlberto

Boretti autosport.com

Paper: Sorniotti, Aldo, and Massimiliano Curto. "Racing Simulation of a Formula 1 Vehicle with Kinetic Energy Recovery System." SAE Digital Library. SAE International. Web. 25 Sept. 2009.

Published by SAE International with a Product Code of PT-159, ISBN of 978-0-7680-7994-4, and 56 pages in a softbound binding.Cross, Douglas. "Optimization of Hybrid Kinetic Energy Recovery Systems (KERS) for Different Racing Circuits." SAE Digital Library. SAE International. Web. 25 Sept. 2009.

‘DESIGN AND ANALYSIS OF KINETIC ENERGY RECOVERY SYSTEM IN BICYCLES’, International Journal of Innovative Research in Science,

http://formula1.about.com/od/drivers/a/Driver_Weights.htm

http://seminarprojects.com/Thread-kinetic-energy-recovery-system-full-report#ixzz2kKsNsWbV

http://www.f1fanatic.co.uk/2009/01/11/kers-explained-how-a-mechanical-kinetic-energy-recovery-system-works/

http://www.racecar-engineering.com/articles/f1/flywheel-hybrid-systems-kers/

http://answers.yahoo.com/question/index?qid=20090611003743AAxdsXj

http://www.formula1.com/inside_f1/understanding_the_sport/8763.html http://www.sportinglife360.com/index.php/the-advantages-and-

disadvantages-of-kers-in-a-formula-one-car-6650/