The document discusses flywheel energy storage systems (FESS). It first provides an introduction to energy storage and defines FESS. It then reviews literature on FESS technology and applications. The main components of FESS are described as the flywheel rotor, electric machine, power electronics, bearings and housing. Examples of FESS applications discussed include use in the Porsche 911, transportation, railways, and spacecraft. FESS provide advantages like high power capability and long lifespan but also have limitations such as potential energy losses over time.

1. FLYWHEEL ENERGY STORAGE SYSTEM
GUIDED BY
Mr. VISHNU PRATHAP
ASSISTANT PROFESSOR
MECHANICAL DEPARTMENT
1
PRESENTED BY
ARUN ASOKAN
REG NO: 14005265
ROLL NO: 15
1

2. CONTENTS
 Introduction
 Literature Review
 Flywheel Energy Storage System(FESS)
 Component of FESS
 FESS in Porsche 911
 FESS in transportation
 FESS in railway
 FESS in spacecraft
 Advantages
 Limitations
 Conclusion
 References
2

3. INTRODUCTION
 Energy storage is becoming increasingly important to accommodate the
energy needs of a greater population.
 Conventional storage system is Uninterruptible Power Supply(UPS) system.
 UPS system is based on the lead-acid battery.
 Flywheel Energy Storage System(FES) can represent a clean substitution
technology for conventional UPS system.
3

4. LITERATURE REVIEW4
SL.
NO
TITLE OF THE
JOURNAL (YEAR)
AUTHOR NAME,
JOURNAL NAME
MAIN POINTS
1 A comprehensive
review of Flywheel
Energy Storage System
technology
(2017)
S.M. Mousavi G,Faramarz
Faraji , Abbas Majazi &
Kamal Al-
Haddad,
Renewable and
Sustainable Energy
Reviews
• The typical overview of FESS operation
as an electric supply charges the flywheel
that stores energy in the form of kinetic
energy.
• Comprehensive review of FESS in
different applications
2 A Review of Flywheel
Energy Storage System
Technologies and Their
Applications
(2017)
Mustafa E. Amiryar &
Keith R. Pullen,
Applied Science
• Critical review of FESS with reference to
its main components
• The main applications of FESS in
transportation, railway and space are
explained

5. LITERATURE REVIEW5
SL.
NO
TITLE OF THE JOURNAL
(YEAR)
AUTHOR NAME,
JOURNAL NAME
MAIN POINTS
3 Design and Analysis of a
Unique
Energy Storage Flywheel
System—An Integrated
Flywheel, Motor/Generator,
and Magnetic Bearing
Configuration
(2015)
Arunvel Kailasan,
Tim Dimond,
Paul Allaire&
David Sheffler,
Journal of
Engineering for Gas
Turbines and Power
• Design of the composite rotor is studied
• A three-dimensional analysis was done on
the entire structure.
• The different parameters of the magnetic
bearing are calculated.

6. Flywheel Energy Storage System(FESS)
 A flywheel stores energy in a rotating mass, depending on the
inertia and speed of the rotating mass.
 According on the need of the grid, the kinetic energy is transferred
either in or out of the flywheel.
6

7. Flywheel Energy Storage System(FESS)
 Flywheel is connected to a machine that works as either the motor or
generator.
 The energy conversion in a FESS is accomplished by the electrical
machine and a bi-directional power converter.
7

8. Components of FESS8
 Flywheel Rotor
 Electric Machine
 Power Electronics
 Bearings
 Housing

9. FLYWHEEL ROTOR
 The energy stored in flywheel is given by
E = ½ I ω ^2
where E is the stored kinetic energy, I is the moment of inertia,
and ω is the angular velocity.
 The maximum specific energy is given by
where σ is the maximum stress, ρ is the density of the flywheel and
K is the shape factor
9

10. FLYWHEEL ROTOR
 The stored energy can be optimized either by increasing the
spinning speed (ω) or increasing the moment of inertia (I).
 Two type FESS
Low Speed FESS
High speed FESS
10

11. ELETRIC MACHINE
 The electrical machine is coupled to the flywheel to enable the
energy conversion and charging process.
 The machine acting as a motor, charges the flywheel by accelerating
it and drawing electrical energy from the source.
 The stored energy on the flywheel is extracted by the same machine,
acting as a generator.
 Common electrical machines used in FESS are
 Induction Machine(IM)
Variable Reluctant Machine (VRM)
 Permanent Magnet Machine (PM)
11

12. POWER ELECTRONICS
 The energy conversion in a FESS is accomplished by the electrical
machine and a bi-directional power converter.
 The power electronic converter topologies that can be used for FESS
applications are
DC-AC
AC-AC
 AC-DC-AC
 The widely used configuration of power converters in FESS is
AC-DC-AC configuration
12

13. BEARINGS
 Bearings are required to keep the rotor in place with very low
friction to provide a support mechanism for the flywheel.
 Different type of bearing systems are
Mechanical bearing
Magnetic bearing
 The widely used bearing technology is magnetic bearing.
13

14. HOUSING
 The housing has two purposes
To provide an environment for low gas drag.
For the containment of the rotor in the event of a failure.
 The housing or enclosure is the stationary part of the flywheel and is
usually made of a thick steel or other high strength material.
 The container holds the rotor in a vacuum to control rotor
aerodynamic drag losses by maintaining the low pressure inside the
device.
14

15. FESS in Porsche 91115
 The battery based electric vehicle was replaced with the flywheel
concept.
 Increase the fuel-efficiency and eco-consciousness of the vehicle.
 Energy wasted while braking is converted into stored energy by
flywheel.

16. FESS IN TRANSPORTATION
 Flywheels are used in hybrid and electric vehicles to store energy,
for use when harsh acceleration is required or to assist with uphill
climbs.
 Energy from regenerative braking during vehicle slowdown is stored
in flywheels.
 In electrical vehicles with chemical batteries as their source of
propulsion, flywheels are considered to cope well with a fluctuating
power consumption.
16

17. FESS IN SPACECRAFT17

18. FESS IN SPACECRAFT
 In space vehicles where the primary source of energy is the sun, and
where the energy needs to be stored for the periods when the
satellite is in darkness.
 Initially designs used battery storage, but now FESS are being
considered in combination with or to replace batteries.
 FESS is the only storage system that can accomplish dual functions,
by providing satellites with renewable energy storage in conjunction
with attitude control.
18

19. FESS IN RAILWAY
 The reuse of regenerative energy from vehicle braking is the
important benefit of using energy storage in electrical railways.
 It can increase electrical railway energy efficiency.
 Regenerative brake decelerates the train by changing its kinetic
energy into electricity and it can be fed back to the power grid in a
short time or stored until required.
19

20. ADVATNAGES
 Flywheels are not as adversely affected by temperature changes.
 High power capability
 Instant response
 Working lifespan is high.
 They are also less potentially damaging to the environment.
 It is possible to know the exact amount of energy stored by a simple
measurement of rotation speed.
20

21. LIMITATIONS
 Primary limits of flywheel design is the tensile strength of the
material used for rotor.
 Traditional flywheel systems require strong containment vessels as a
safety precaution.
 FESS using mechanical bearing can lose 20% to 50% of their
energy in 2hours.
21

22. CONCLUSION
 Flywheels are one of the most promising technologies for replacing
conventional lead acid batteries as energy storage systems for a
variety of applications.
 The main components flywheel rotor, electric machines, power
electronics, and bearing systems for flywheel storage systems are
described.
22

23. CONCLUSION
 The main applications of FESS in transportation, railway and space
are explained.
 FESS offer the unique characteristics of a very high cycle and
lifespan.
 Future work will include the detailed modelling and analysis of a
flywheel system for backup power and grid support applications.
23

24. REFERENCE
Arunvel Kailasan,Tim Dimond,Paul Allaire&Da Sheffler, Design and Analysis
of a Unique Energy Storage Flywheel System—An Integrated Flywheel,
Motor/Generator,and Magnetic BearingConfiguration/Journal of Engineering
for Gas Turbines and Power APRIL 2015, Vol. 137 / 042505
Mustafa E. Amiryar & Keith R. Pullen, A Review of Flywheel Energy Storage
System Technologies and Their Applications/Applied Science Appl. Sci.
2017,Vol.286,7
S.M. Mousavi G et al, Renewable and Sustainable Energy Reviews /Renewable
and Sustainable Energy Reviews 67(2017)477–490
24
[1]
[2]
[3]

25. THANKYOU…..
25

26. 26