SMES power generation

1. Superconducting Magnetic Energy Storage
Presented By:
Asit Meher
(SMES)1

2. List of Contents
1. Introduction
2. History
3. SMES System
4. Components of SMES System
5. Classification of SMES systems
6. Design of SMES
7. Applications
8. Common Challenges
9. Conclusion
10. References
2

3. 1. Introduction:
Superconducting Magnet :- A superconducting magnet is an electromagnet made from coils of superconducting
wire. They must be cooled to cryogenic temperatures during operation.
o In its superconducting state the wire can conduct much larger electric currents than ordinary wire, creating intense
magnetic fields.
o (T<Tc), (I<Ic), (B<Bc)
Energy Storage:- Energy storage is the capture of energy produced at one time for use at a later time.
Superconducting Magnetic Energy Storage:- An energy storage system that stores energy in the form of dc
electricity by passing current through the superconductor and stores the energy in the form of a dc magnetic field.
o SMES  storing ½ Li2 energy in superconducting indicator  Retrieving the energy to utility load when required
3

4. Comparison of storage methods in electrical networks
Methods of Storage
Space
Requirement Life
Time
No. of
cycles
Cycle
Duration Efficiency Cost
Max. Power/
Energy
Electrochemical:
Lead Acid Battery
Nas Battery
Low
Low
Low
Medium
Limited
Limited
½ to 3 h
½ to 3 h
50-90%
50-90%
Medium
Medium
Low
Low
Mechanical:
Pump Storage
Flywheel
High
Medium
High
High
High
High
¼ to 24 h
2s to 1h
70-75%
70-90%
Low
High
Low to
Medium
Low to
Medium
Inductive:
Superconducting Magnet Medium High Unlimited 2s to 24h 85-95% High High
4

5. Main Characteristics of SMES:
1.SMES does not convert
electric energy into mechanical
or chemical energy and vice
versa.
2. High energy conversion
efficiency(>95%)
3. There is no energy loss in
SMES (the only loss is about
2-3% in the inverter/ rectifier
system.)
4.High power density but
rather low energy density.
5.No moving parts/ low
maintenance.
6.SMES has very small
response time and delivers
power almost
instantaneously.
5

6. History 6

7. 1911
• Superconductivity was first observed by Kamerlingh Onnes in a laboratory that
was also the first to produce liquid helium
1969
• First concept was proposed by Ferrierin in France.
1971
• Research performed in University of Wisconsin in the US.
• This research led to construction of the first SMES device.
1972
• The Los Alamos Scientific Laboratory (LASL) was asked by the U.S. Atomic
Energy Commission to look into SMES
1980
• A point reference design for a 1-GWh SMES unit was described by Los Alamos.
• The goal of this effort was to generate sufficient design detail on a SMES unit to
obtain a realistic cost estimate of the total system.
7

8. 1985
• Some work on SMES had been carried out in Japan and two workshops were
held to evaluate the status of the technology and to discuss future projects.
1985
• The New Energy Development Organization in Japan has established a program
to evaluate SMES and to establish a design for a 10-MWh prototype.
1997
• first significant size HTS-SMES was developed by American Superconductors.
Then it was connected to a scaled grid in Germany.
8

9. SMES System:
3  Line
Load
Transformer
AC / DC
Converter
Control System
Cold Box
S.C. Coil
Fig:1
9

10. Operating Principle:
 The operation of SMES is based on the fact that a current will continue to flow in a superconductor even
after the voltage across it has been removed.
 A SC coil that is cooled below its critical temperature has negligible (zero) resistance. Thus the current
will continue to flow in it.
 The stored energy is inductive= ½ Li^2
 Charging Phase: Since the current flows only in one direction, the PCS (Power Conditioning System)
must produce a positive voltage across the coil to store energy. This increases the current.
 Discharging Phase: The PCS are adjusted to make the system look like a load across the coil by
producing a negative voltage causing the coil to discharge.
10

11. Components of SMES:
1. Superconducting Coil with Magnet
(SCM)
2. Power Conditioning System(PCS)
3. Cryogenic System (CS)
4. Control Unit(CU)
SMES
1.SCM
2.PCS
3.CS
4.CU
11

12. Components:
 Power Conditioning System(PCS): Transformer, Inverter and Firing circuit
 Cryogenic System (CS): Refrigerator, Vacuum pump and Helium tank
 Control Unit(CU): DSP or Microcontroller, Interface circuit
Fig.2
12

13. Classification of SMES:
1. Very Large Units(100 GJ)
2. Medium & Small Units(10 to 100 MJ)
3. Micro SMES (1 TO 30 MJ)
13

14. Fig:3. 2MJ SMES
14

15. 3.Design of SMES 15

16. C. Superconductor (Sub Optimal Design)
I = 390 A:E = 770 KJ
A. Normal Conductor (Brooks Coil)
I = 4.0 A:E = 154J
B. Superconductor
(Global Optimum Design)
9.6 cm
9.6 cm
9.6 cm
2 a
(2 8.8 cm)
(0.3 cm)
b = 45 cm
(130 cm)
c= 1.4 cm
b = 45 cm
(38.6 cm)
Wire Length = 8 KM
Wire Dia = 1 mm, (Nb – Ti/Cu Mix)
Optimum Design of SC Coil for
Energy storage:
Fig:4
16

17. Brooks Coil
Suboptimum Design
Global Optimum Design
I = 150 A, L = 19.3H, E = 218 kJ,
b = 9.6 cm, Mean Dia = 28.8 cm,
Radial Thickness = 9.6 cm, Bmax = 8.4 T
I = 390 A, L = 10.1H, E = 770 kJ,
b = 45 cm, Mean Dia = 40 cm,
Radial Thickness = 14 mm, Bmax = 5.4 T
Modified Characteristics
I = 770 A, L = 5H, E = 1480 kJ,
b = 45 cm, Mean Dia = 130 cm,
Radial Thickness = 3 mm, Bmax = 1.8 T
Critical Characteristics
1400
1200
1000
800
600
400
200
0
0 2 4 6 8 10 12 14
B (Tesla)
I(amps)
17

18. Vacuum Vessel
Temperature
sensors
LHe vessel
L N2 Vessel
Ground level
LHe level
indicator
S.S. 316L
Studs
SS support tubes
Evacuation-port
Copper Baffle
Current Leads
LHe transfer line
He Gas recovery
Top flange
Hall Probe for field
measurement S.C coil
Fig:5
18

19. 6.Application 19

20. 6.1. Power System:
Type
Enhanced power system
stability
Power quality
improvement
20

21. A. Enhanced Power System Stability
Fig. 6. Schematic diagram of an SMES unit for damping system
oscillations
1.Damping system oscillations
2.Improving voltage stability
21

22. B. Power Quality Improvement
• 1) Spinning reserve
• 2) Improving FACTS performances
• 3) Compensation of fluctuating loads
• 4) Reducing area control error
• 5) Load leveling
• 6) Protection of critical loads
• 7) Backup power supply
• 8) Improving power system symmetry
22

23. Fig. 7. Schematic improving FACTS performances
using SMES
Fig. 8. Schematic diagram to compensate for
fluctuating load
2) Improving FACTS performances 3)Compensation of fluctuating loads
23

24. Fig. 5. SMES system for protection of
distributed critical loads
Fig. 6. Configuration of an asymmetrical compensation
system with SMES
24

25. 6.2. Industrial Use:
• Paper Industry
• Petrochemical
• Chemical & Pharmaceutical
Fig:9
25

26. 6.3. Research Institutes:
• Researches on SMES are focused on three aspects: (a) PCS,
(b) applications of SMES, and (c) SCM. The researches on
the PCS mainly include circuit topologies and control
techniques. The researches on applications are to explore
feasible applications and control strategies. The researches on
the SCM are concerned on design and optimization of the
SCM.
Fig:10 IIT Kharagpur Lab
26

27. Common Challenges:
• Main drawback of the SMES technology is the need of large amount power to keep the
coil at low temperature, combined with the high overall cost for the employment of such
unit.
• To achieve commercially useful levels of storage, around 1 GWh a SMES installation
would need a loop of around 100 miles (160 km).
• Another problem is the infrastructure required for an installation.
27

28. References:
• Xue, X. D., Cheng, E. KW. & Sutanto, D. (2005). Power system applications of
superconducting magnetic energy storage systems. Conference Record of the 2005 IEEE
Industry Applications Conference (pp.1524-1529). Hong Kong: IEEE Industrial
Applications Society.
28

29. THANK YOU
29