3rd The International Conference on Renewable Energy Research and Applications
19-22 Oct 2014 Milwakuee-USA
Maglev Wind Generator
An efficient form of vertical axis wind turbine
Santoshkumar Jiledar Chaturvedi
Department of Electrical Engineering
Sardar Patel College of Engineering
Mumbai-400058, India
csantoshk65@gmail.com
Mahesh Madhukar Utekar
Department of Electrical Engineering
Sardar Patel College of Engineering
Mumbai-400058, India
utekarmahesh@gmail.com
Abstract— This paper gives alternate configuration of wind
turbine for power generation. Magnetic repulsion gives
advantage of no use of ball bearings hence turbine is suspended
in zero gravity & design of turbine gives universal rotation.
Power is generated using axial flux generator with use of
permanent magnets & set of coils. Hence efficient use of green
energy is possible using this model on higher scale.
Keywords— magnetic levitation, rare earth element
magnets, vertical axis wind turbines and wind generators.
I. INTRODUCTION
Renewable energy is generally electricity supplied from
sources such as wind power, solar power, geothermal energy,
hydropower and various forms of biomass. The popularity of
renewable energy has experienced a significant upsurge in
recent times due to the exhaustion of conventional power
generation methods and increasing realization of its adverse
effects on the environment. This project focuses on the
utilization of wind energy as a renewable source. The aim of
this major qualifying paper is to design and implement a
magnetically levitated vertical axis wind turbine system that
has the ability to operate in both high and low wind speed
conditions. Our choice for this model is to showcase its
efficiency in varying wind conditions as compared to the
traditional horizontal axis wind turbines. This contributes to its
steady growing popularity for the purpose of mass utilization
in the near future as a reliable source of power generation.
II. LITERATURE SURVEY
Among many types of wind turbines, vertical axis and
horizontal axis these two types are very famous. The former
due to its seldom usage and exploitation is quite unpopular,
While the latter is more conventional and common type
everyone has come to know.
Further there are two famous types under vertical axis
wind turbines, Darrieus wind turbine and Savonius wind
turbine. After a thorough research into both sub types of
vertical axis wind turbine rotor configurations, we decided to
base the foundation of our design on the Savonius model and
the final design is in Figure 1.
ICRERA 2014
Figure 1- Side View of Generator [8]
III. CONSTRUCTION DETAILS
Entire construction of this maglev wind generator can be
divided into following parts:A. Magnetic Levitation
Magnetic levitation is a method by which an object is
suspended in air so effect of gravity on that object reduces
significantly with no support other than magnetic fields. Here
magnetic pressure is used to mainly counteract the effects of
the gravitational forces.
Magnetic levitation is an extremely efficient system for
wind energy. Here’s how it works:At the bottom one magnet is placed. It repels the other
magnet which is welded to the shaft of generator. The shaft
contains the vertically oriented blades of the wind turbine.
Now due to this repulsion power between the magnets the
upper magnet attached to shaft is suspends is air suspended,
replacing the need for ball bearings. For this levitation full
permanent rare earth magnets made from neodymium are
used. Due to this no energy loss through friction occurs in
generator. This also helps in reducing the maintenance cost
and increases the lifespan of the wind generator.
3rd The International Conference on Renewable Energy Research and Applications
19-22 Oct 2014 Milwakuee-USA
value, no matter from which direction wind is flowing. Due to
this the wind tale circuitry required in conventional wind mills
is eliminated here.
Figure 2 -Concept of Magnetic Levitation [7]
Some factors need to be assessed in choosing the
permanent magnet selection that would be best to implement
the maglev portion of the design. Understanding the
characteristics of magnet materials and the different
assortment of sizes, shapes and materials is critical. There are
four classes of commercialized magnets used today which are
based on their material composition each having their own
magnetic properties [5]. The four different classes are Alnico,
Ceramic, Samarium Cobalt and Neodymium Iron Boron also
known Nd- Fe-B. Nd-Fe-B is the most recent addition to this
commercial list of materials and at room temperature exhibits
the highest properties of all of the magnetic materials. It can
be seen in the B-H graph shown in Figure-3 that Nd-Fe-B has
a very attractive magnetic characteristic which offers high flux
density operation and the ability to resist demagnetization. So
the Nd-Fe-B is preferred here for levitation.
Figure3–B-H Curve of Various Magnetic Materials [6]
B. Wind Turbine Design
It is observed that in our streamlined design it
concentrates the mass momentum of the wind to the bottom of
the sails and allows for smoother torque during rotation. A
standard Savonius model for this design would have created a
lot of instability around the shaft and on the base which could
eventually lead to top heaviness and causing the turbine to tip
over. The main factor for our design is due to its attachment to
the stator of our generator as shown in Figure 4.
In addition to this Savonius design provides universal
rotation. By universal rotation we mean that the blades will
start rotating once the speed of air is more than the cut off
ICRERA 2014
Figure 4 -Rotors Connected to Stator [8]
C. Generator Design
When designing a generator it is important to have a firm
grasp of the basic laws that govern its performance. In order to
induce a voltage in a wire a nearby changing magnetic field
must exist. The voltage induced not only depends on the
magnitude of the field density but also on the coil area. The
relationship between the area and field density is known as
flux (Φ) [1]. The way in which this flux varies in time depends
on the generator design. The axial flux generator uses the
changing magnetic flux to produce a voltage. The voltage
produced by each coil can be calculated using Faraday's law of
induction: V = N dø/dt [3].
In the design of stator we have put 10 set of coils in 10
slots. Each coil consists 300 turns of copper wire. The copper
wire used here is of 28 SWG (standard wire gauge).Each one
of our coils has a measured resistance of 40Ω; a smaller gage
wire would further reduce this resistance.
Figure 5 –Copper coils of 300 turns each [8]
For rotor designing two circular plates containing 10
permanent magnets on each are used here. The angular
distance between to magnets is 36 degree equal to the distance
between two coils. The magnets placed on these two plates
create the magnetic fields. These magnets are of ferrite type
with the powers of 2500 gauss each.
3rd The International Conference on Renewable Energy Research and Applications



Rotor containing magnets
Stator containing coils
Figure 6 –Stator & Rotor [8]

In our design we have chosen to sandwich the coils
between two attracting magnets [4]. The magnets are so
arranged that if one pair’s magnetic field is in upward
direction then adjacent pair’s magnetic field will be in
downward direction.


Field
Figure 7 – Coils and Magnets arrangement at rotor [8]
The magnitude of the flux is greater when the coil in a
magnetic field is perpendicular to the field [2]. So is the
reason for the above design.
When due to wind turbine starts rotating the magnetic
field created by the magnets also rotates which get cut by the
stationary coils and here comes the Faraday’s law of
electromagnetic induction due to which emf is induces in
coils.
IV. FEATURES
A. Project output:
Voltage: 8.48volts (pk-pk)
Frequency: 23.63Hz
Rotation Speed of turbine: 320 rpm
Current: 16.8 mA

VI. ACKNOWLEDGMENT
The authors wish to thank our faculty and colleagues in
SPCE and VJTI for their support in writing this paper,
especially: Vidya Joshi for assistance with the diagrams, Popat
Kandhare for a useful discussion over the content, and Santosh
kavare for proof-reading.
1.
2.
3.
5.
6.
7.
B. Constructional Features of Maglev Wind Generator
 The vertically oriented blades of the wind turbine are
suspended in the air replacing any need for ball
bearings.
ICRERA 2014
For the levitation full permanent rare earth magnets
are used which are very reliable and durable.
No requirement of wind tale circuitry due to
universal rotation given by Savonius design.
Due to use of magnetic levitation at the base of
turbine effect of gravity on turbine operation is much
lesser. It provides less start up energy and reaches to
high
speed in less time.
Frictional losses are almost negligible due to
levitation which reduces the starting torque
requirement.
No use of Dynamo so elimination of carbon brushes.
High rotating speed: the rotating speed is increases
under the same wind speed compare to conventional
one.
High power output: the power output actual is raise
adherently under the same wind speed.
V. CONCLUSION
The important concept of magnetic levitation explained in
this paper gives the frictional losses which can assume to be
negligible. So this helps in achieving greater efficiency. If we
use more numbers of coils in stator and more numbers of
magnets in rotor the emf generated in coils will be more.
To get more output another way is to reduce turbine’s
own inertia by using lighter weight materials for turbine. So
that for the same wind speed it will rotate faster, hence it will
generate more power.
4.
Figure 8 – Practical Model Output [8]
19-22 Oct 2014 Milwakuee-USA
8.
VII. REFRENCES
Giancoli, Douglas C. Physics for scientists &
engineers
with modern physics. Upper Saddle
River, N.J: Prentice Hall, 2000.
Gonen Turan, Electric Power Distribution System
Engineering, Boca Raton: CRC P,2008.
Hambley, Allan R. Electrical Engineering Principles
and Applications (4th Edition).Upper Saddle River:
Prentice Hall, 2007.
Mohan, Ned. Electric Drives An Integrative
Approach, Mnpere, 2003.
“Magnet Design”. 2000 Magnet Sales &
Manufacturing Company, Inc.
http://www.magnatokyo.com/eng/service/tokusei.html
http://ffden2.phys.uaf.edu/212_fall2009.web/Wendy_
Presler/Homepage.html
Diploma Final Year Project Report on “Maglev Wind
Generator” by Mahesh Utekar in VJTI (2011-12)