EE-GN042.pdf

2013 International Conference on Renewable Energy and Sustainable Energy[ICRESE’13]

978-1-4799-2075-4/13/$31.00 ©2013 IEEE

492

Harvesting Energy from Railway locomotive and

Coaches by Piezoelectric Material

Vivek Singh Rana

B.tech Pursuing,ECE Department

SRM University NCR Campus

Ghaziabad, India

[email protected]

Shreya Puri

B.Tech Pursuing, ECE Department

SRM University NCR Campus

Ghaziabad, India

[email protected]

Abstract— This paper deals with harvesting energy by

Piezoelectric Materials from railway locomotive and coaches

vibrations. In this scope,piezoelectric material becomes a strong

candidate for energy generation and storage in future

application. Railway locomotive, Coaches for express trains and

goods trains due to heavy load produce vibration during running

time. These vibration can be converted to electricity by

piezoelectric crystal. In this paper we discussed the use of

piezoelectric crystal to generate electricity from surrounding

vibrations in order to meet our power demands.

IndexTerms—Piezoelectric, PZT 5A, lead zirconate titanate,

d33T, S33E, T3, E33T

I. INTRODUCTION

Man has needed and used energy at an increasing rate for

his purpose. Due to this a lot of energy resources have been

exhausted and wasted. The utilization of waste energy from

railways locomotive and coaches is very much relevant for

country(India) which has fourth largest rail network of 65,000

km in the worldin form of vibration and it can be made

possible for utilization it will be very useful energy sources.

This energy can be tapped and converted to electrical form. In

this paper, piezoelectric crystals were used as a medium.

These piezoelectric crystals convert the mechanical vibrations

into electrical energy.

II. PIEZOELECTRIC CRYSTAL

One of the most suitable methods for obtaining the energy

from surrounding a system needed is achieved by using

piezoelectric crystals. The piezoelectric crystals are subjected

to vibration they generate a voltage, commonly known as

piezoelectricity. It has a crystalline structure that converts an

applied vibration into an electrical energy .The piezoelectric

effect exists in two properties: The first is the

directpiezoelectric effect that describes the material’s ability

to transform mechanical strain into electrical charge. The

second form is the converse effect, which is the ability to

convert an applied electrical potential into mechanical strain

energy. These properties allow the material to function as a

power harvesting medium .[6]

A. The piezoelectric effect

The piezoelectric effect is exhibited by a number of

naturally-occurring crystals, for instance quartz, Tourmaline

and sodium potassium tartrate. For a crystal to exhibit the

piezoelectric effect, its structure should have no center of

symmetry. A stress (tensile or compressive) applied to such a

crystal will alter the separation between the positive and

negative charge sites in each elementary cell leading to a net

polarization at the crystal surface. The effect is practically

linear, i.e. the polarization varies directly with the applied

stress, and direction-dependent, so that compressive and

tensile stresses will generate electric fields and hence voltages

of opposite polarity. The mechanical strength values of Piezo

ceramic material up to 250 MPa (2500 x 105 N/m²) before it

breaks mechanically. For practical applications, this value

must not be approached because depolarization occurs at

pressures on the order of 20 to 30 % of the mechanical

limit.Besides the crystals mentioned above, an important

group of piezoelectric materials are the piezoelectric ceramics,

of which PZT, or lead zirconate titanate (Pb[Zr(x)Ti(1-x)]O3 is

an example. These materials are represented by the formula

ABO3, Perovskite crystalline structure wherein A-site denotes

large divalent metal ion such as Pb and B-site denotes smaller

tetravalent ion such as Ti or Zr (Fig 1)

Fig. 1- PZT elementary cell

The maximum charge density which can be generated is

about 0.275 C/m2 once a PZT-5A element has produced a

charge density of 0.275 C/m2, as for the dynamic case, it is

almost completely irreversibly depolarized.[7]


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493

B. Advantage of ceramic over single crystals

Higher piezoelectric coefficient, ease of fabrication into

components of any shape and size, mechanically hard and

robust, chemically inert and completely unaffected by

atmospheric humidity. In contrast, single crystals must be cut

along certain crystallographic direction, thus limiting their

possible geometrical shapes.

C. Technical details

With piezoelectric ceramics, the relationship between the

applied stress and the resultingresponses depend upon:

- Piezoelectric properties of the ceramic.

- Size and shape of the element, and

- Direction of the electrical and mechanical vector

quantities.

To identify directions in a piezoelectric element, three axes

termed as 1, 2 and 3; whichare analogous to the classical three

dimensional orthogonal set of axes X, Y and Z areused.

Material properties along the 1 and 2 axes are identical to each

other but differentfrom those along the 3 axis. For maintaining

simplicity, references are made only to the3 and 1 direction.

The poling or 3 - axis is invariably taken parallel to the

direction ofPolarization within the ceramic (Fig 2(A)). The

polar axis is induced during theManufacturing process by

treatment with a high voltage DC field applied between the

pair of electrode faces to align the domains of the material in

the direction of the field.

Fig. 2 (A) Fig. 2(B)

The polarization vector P is represented by an arrow

pointing from the positive to thenegative poling electrode. In

shear mode operations, the poling electrodes are later removed

and replaced by a set of electrodes on the second pair of the

faces. The 3-axisis not altered, but it becomes parallel to the

new electrode faces as seen on the finishedelement (Fig 2(B)).

Depending on the independent variable choice a piezoelectric

coefficient are defined as

dij = E

= T ….(1)

eij = E = -

S …..(2)

gij = - D =

T …..(3)

hij = - D = -

T ….(4)

g is the piezoelectric voltage coupling, d contains the

piezoelectric coupling terms which relate the electrical and

mechanical properties of the material, S is the strain

(dimensionless), D is the electric displacement or charge

density (C/m2), E is the electric field (V/m) and T is the

applied stress (N/m2)

[8]

Piezoelectric charge coefficient (d constant)

The piezoelectric d constant is a measure of the charge

density per unit stress or the

Strain per unit field.

dik =coulombs/meter2 = Coulomb

newton/meter2 Newton …(5)

Piezoelectric coefficients with double subscripts link

electrical and mechanicalquantities. The first subscript gives

the direction of the electrical field associated withthe voltage

applied or the charge or the voltage produced. The second

subscript gives the direction of mechanical stress or the strain

.The piezoelectric charge coefficient d33 applies when the

force in the 3-direction (along thepolarizationaxis) and is

impressed on the same surface on which the charge is

collected(Fig 3(A)), whereas d31 applies when the charge is

collected on the samesurface as before but force is applied at

right angles to the poling axis (Fig 3(B) )

Fig. 3(A) fig. 3(B)

D. Piezoelectric Voltage coefficient (g constant)

The g coefficient is a measure of the field per unit stress or

strain per unit charge density.

gij=volt/meter = Volt-meter

Newton/meter2 newton ..…(6)

Output voltage is applied by multiplying the calculated

electric field by the thickness of theceramic between the

electrodes. The first subscript indicates the direction of the

generated voltage and the second indicates the direction of the

force. A "33" subscript signifies that the electrical field

generated and the mechanical stress are both along

thePolarization(Fig 3(a)). A "31" subscript signifies that the

pressure is applied at right angles to the polarization axis but

the voltage appears on the same electrodes as in the "33"Case

(Fig 3(b)) [3]

E. Relationship Between g and d coefficients:

At frequencies far from resonance effects, piezoelectric

ceramic transducers are fundamentally capacitors.

Consequently, the voltage coefficient gik are related to the

chargeCoefficient dik by the dielectric constant Ki, as in a

capacitor the voltage V is related toCharge Q by the

capacitance C.

Q = C. V …. (7)

d33 =kt3o.g33…...(8)

d31= kt3o.g31 ..…(9)


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494

Coupling Coefficients:

Sometimes also referred as electromechanical coupling

coefficients, these describe theConversion of energy by the

ceramic element from electrical to mechanical form or vice

versa.

K= mechanical energy

Electrical energy ….(10)

Subscripts denote the relative directions of the electrical

and mechanical quantities and theKind of motion involved. kp

signifies the coupling in a thin round disc polarized in radial

expansion and contraction, whereas k33 is appropriate for a

long thin bar or rod, electrode on the ends, poled lengthwise

and vibrating in simple length expansion or contraction. K31

relates to a thin long bar, electrode on a pair of long faces,

poled in thickness and vibrating in the longitudinal dimension.

Since these coefficients are energy ratios, they are

dimensionless.Coupling coefficients of PZT is 1000.

Fig. 4

III. CALCULATION

We are using PZT-5A piezoelectric element of plate type

of thickness is 0.03 m and radius is 0.06 m for locomotive,

coaches of Express trains) and radius is 0.03 m for goods train

coaches (fig. 5) .The piezoelectric is set above spring/soccer’s

(Fig. 4)

Fig. 5

Area =

Assume radius=r=0.06 m

= 3.1428

Change in length = original length.S33E.T3

[1] ….(11)

S33E=18.8* 10-12

Pa-1

Capacitance =E33T*Area of plate

[1]

Thickness …..(12)

Voltage = d33F[1]

Capacitance .…(13)

S33E=Elastic constant

E33T=Charge Density=5.015 10 -9

C/m2 [1]

d33=Displacement coefficient

= 593 10-12

C/N

Pp=dt[1]

…(14)

d=strain

t=pressure

p=charge

P=VI

A. Calculation process

Fig. 6

Table 1

Diesel

Locomotive

Electrical

Locomotive

AC Chair car

coach Coach goods

Train

Weight

(Tones)[6]

120 240 40 68

Helical Spring[6] 16 16 16 16

Rubber Spring[6]

8 8 8 8

Pressure(Stress)

Pressure=

force/Area

(N/m2)

4.419 105 8.846 10

5 1.473 10

5 1.005 106

Capacitance 1.819 1.819 1.819 1.819


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495

Voltage (KV) 1.567 3.135 0.52251 0.3556

Power per coach or per locomotive(MW)

0.1466 1.172 0.0054 0.0175

Estimated change in length of material used is within the

range of allowed vibration parameter test ICE 61373 of RDSO

Lucknow of Locomotive orcoaches’i.e. 35-50 10 -3m.

IV. METHOD OF EXTRACTION AND SCOPE

The piezoelectric material is place on the spring in

locomotive (fig.7)

Fig. 7

The following three methods of extraction are found -

1->We can store the charge or energy in capacitor of 50

KV 1 nF (Nano Farad) High Voltage Polystyrene capacitor

(Fig. 8).

Fig. 8

We can extract energy from capacitor at railway station by

heavy voltage wires.

2-> New Electric locomotive (A.A.B locomotive)

generates power in range of KV and give it to railways electric

grid so that S.S.P (substation) (Fig. 9) whose main function is

to maintain the voltage of 25 KV in 50 km (for 10 locomotive

in the 50 km section). So, the Efficiency of S.S.P substation is

increased .

3-> We can attach all coaches to the locomotive and give

the high voltage to electric grid such that efficiency of S.S.P

increases (by 10 -50 locomotive in 50 kmrange). Extra voltage

is taken by S.S.P and it can replace substation (fig. 10) from

transmission grid. This can replace the substation and thus

reduce the need of thermal power plant. So, coal consumption

used in thermal power plant for electricity generation is

reduced.

Fig 9-S.S.P Sub Station

Fig. 10- Transmission Grid

Electricity generated by this paper’s method can reach

distant places (example: villages, hilly areas) where electricity

from power plants cannot reach (but railway track is

there).From this paper, we can say that vibrations from heavy

bodies such as railway locomotives, coaches, Cars, Turbines,

Bridges etc. can be used to make electricity

V. CONCLUSION

The Design of a vibration energy harvesting depends on

the nature of available vibration source.These vibration

sources must be explored in order to generate a model for

them that will serve as a foundation for design of a harvesting

energy from vibration.This paper presents a theoretical

analysis of power generation with PZT ceramics several

important considerations in designing such generators are

explored, including parameter identification, load matching,

voltage generation, stress, strain, efficiency, energy

conversion, and energy storage. Finally, an application of this

analysis is presented where electrical energy is generated from

locomotive and coaches a prototype are made.By

Measurements as well as numerical predictions vibrations

from locomotive and coaches have been presented. The


978-1-4799-2075-4/13/$31.00 ©2013 IEEE

496

experimental results show how large amount of energy is

piezoelectric power generator is developed using a d33 mode

of piezoelectric transducer.

ACKNOWLEDGMENT

There are far too many people to try to thank themall;

many people have contributed to development of this paper.

We owe our deep regards and honor toexpress our Gratitude to

vivek’s (author) father Shri Rajkumar Singh Rana, chief Loco

Inspector Moradabad division northern railway, India for

inspiring and providing technical details for this paper to us.

REFERENCES

[1] Compact Piezo-Based High Voltage Generator - Part I: Quasi

-Static Measurements G. Staines,HelmutHofman, Josef Dommer

,L.L. Altgilbers, Ya. Tkach

[2] Piezoelectric properties of 3-X periodic Pb.ZrxTi1Àx.O3–

Polymercomposites James E. Smay, Joseph Cesarano III and

Bruce A. Tuttle, Jennifer A. Lewisa)

[3] Mohammad mehdizadeh ,Sabu john,Chunh wang”Delination of

structure damage from piezo fibro based degration “Mohammad

Mehdizadeh et al. / International Journal of Engineering Science

and Technology (IJEST)

[4] Patent “Rail vehicle vibrate energy piezoelectric power

generation method system there of CN160209A”

[5] Patent”Rolling stock rail vibration piezoelectric power generating

method and there of CN1610210A

[6] RDSO Lucknow India

[7] R.A.Dorey & R.W.Whatmore Apparent reduction in the value of

the d33 piezoelectric coefficient in PZT thick films Preprint of

paper: R.A. Dorey, R.W. Whatmore, “Apparent reduction in the

value of the d33 piezoelectric coefficient in PZT thick films”,

Integrated Ferroelectrics, 50, pp111-119, 2002.

[8]-Simon P, Burke AF. Nanostructured carbons: double-layer

capacitance and more. ECS Interface, Special issue

Electrochemical Capacitors – Powering the 21st Century, 17(1),

pp. 38-41, Spring 2008.

[9]-Harvesting energy through piezoelectricity in runway by

Long Ki Yau (Derek)

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