harmonics study on distrubution transformer

8/6/2019 Harmonics Study on Distrubution Transformer

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P R O J E C T R E P O R T

Prepared By

INTEGRATED RURAL TECHNOLOGY CENTREM U N D U R , P A L A K K A D

Submitted To

KERALA STATE ELECTRICITY BOARDThiruvananthapuram


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P R O J E C T T E A M

Principal Investigator

Dr. M. P. Parameswaran

Fellow, IRTC

Co-investigators

Dr. R. V. G. Menon (Fellow, IRTC)Mr. K. Bhaskaran (Fellow, IRTC)Mr. R.Satheesh (Scientist, IRTC)

Mr. B.V. Suresh Babu (Scientist, IRTC)

Mr. Haynes Davis (Scientist, IRTC)Mr. Bency Zachariah (Scientist, IRTC)

Mr. Vimal Raj ((Scientist, IRTC)


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C O N T E N T S

ACKNOWLEDGMENT .................................. 5

1 INTRODUCTION .............................. .......... 6

2 SPECIFIC OBJECTIVES OF THE PROJECT ............ 7

3 METHODOLOGY ................................. ....... 7

3.1 Laboratory Study .......................... .... 8

3.2 Real Time Field Study ........................ 8

4 ANALYSIS OF TEST RESULTS ......................... 9

4.1 Laboratory Study .......................... .... 9

4.2 Real Time Field Study ........................ 10

5 CONCLUSIONS ................................ ......... 11

6 ECONOMIC SIGNIFICANCE OF THE STUDY .......... 12

6.1 Consumer End .......................... ....... 12

6.2 Provider End ............................. ...... 12

7 RECOMMENDATIONS ............................ ...... 13

ANNEXE 1

LABORATORY AND FIELD DATA ..................... 15

ANNEXE 2

VOLTAGE AND CURRENT WAVEFORMS ............. 26


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ANNEXE 1

L A B O R A T O R Y A N D F I E L D D A T A

1. LABORATORY DATA

TABLE 1 CFLs of different brands

TABLE 2 CFLs added in 11 steps in single phaseTABLE 3 CFLs connected in balanced condition

TABLE 4 CFLs connected in unbalanced conditionTABLE 5 Transformer loss and primary & secondary harmonics for CFL and

incandescent lamp circuits

TABLE 6 Transformer temperature for the CFL circuitTABLE 7 Transformer temperature for the incandescent lamp circuitTABLE 8 Lumen per watt for different makes of CFLs and incandescent lampsTABLE 9 Simulation of a domestic consumer's load

2. FIELD DATA

TABLE 10 Data at the consumer test pointsTABLE 11 Connected load at test point 1 and 2 as on the dates of measurementsTABLE 12 Data at the transformer end before the replacement

TABLE 13 Data at the transformer end after the replacementTABLE 14 No. of incandescent lamps replaced

ANNEXE 2

V O L T A G E A N D C U R R E N T W A V E F O R M S

1. LAB STUDY

1.1 Addition of CFLs in 11 steps

2. REAL TIME FIELD STUDY

2.1 Test point 12.2 Test point 22.3 Transformer point


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ACKNOWLEDGMENT

IRTC is very happy to extend its thanks to all who participated for the successful completion

of the project.

We are grateful to all the officials of Kerala State Electricity Board who is supported this

project.

We also remember all the advices given by Dr. Padmanabhan Nambiar, Chairman, Dept. of

Electrical Engineering, AITS, Coimbatore.

The support and co-operation of the all the eminent personalities of various institutions and

the natives of Poriyani, Palakkad where the fieldwork was carried out are remembered with

gratitude.

Thank you.


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1. INTRODUCTION

It is well accepted that energy conservation has equal or even more

importance compared with installation of new generating capacities in meeting

the demand for electrical energy. The relevance of Demand Side

Management (DSM), i.e., the energy planning strategy with emphasis on

reducing the energy demand by the use of energy efficient technologies at the

user end, over the Supply Side Management (SSM), has been now

universally recognised.

According to a study done by IRTC, about one third of the total power

consumption of Kerala and three fourth of the peak load, is for lighting

purpose. The study also revealed that the energy consumption could be

reduced significantly if energy-efficient lighting devices like fluorescent tubes

and Compact Fluorescent Lamps (CFLs) are used instead of the ordinary

incandescent bulbs.

However CFLs and other fluorescent lamps with electronic chokes if used in

large numbers may cause, it is feared, severe depression in the power factor

on the one hand and induce high levels of harmonics within the system, which

may lead to higher losses and system instabilities.

Because of the huge demand for the CFLs and electronic choke for the

fluorescent tubes, a number of manufacturers have ventured into this

business and flooded the market with cheap and low quality products. Since

the market is very competitive, the manufacturers are compromising on the

quality of the product so as to offer their products at lower prices. Even the

multinationals and the reputed manufacturers are selling low quality products.

A typical high quality CFL with over voltage protection and well-suppressed

harmonics can cost anywhere between Rs. 300 to Rs. 450. As many as 70 to

80 component parts are required to make the chokes of necessary quality.


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Compared to this cheaper CFLs, without any of the above is being sold at Rs

100 to 120. CFLs that are ridiculously cheap have been dumped with in the

market from China (LEUCI Brand), SreeLanka (Honey Queen), Japan

(MYOTA) and are sold Rs 25 to 30. A large number of consumers maychangeover from incandescent lamps to these CFLs. Electricity Board and

Government may want to encourage this. It has become urgent to the study

the technical performance of these lamps i.e.; impact of harmonics cost

effectiveness etc.

It was suspected that high harmonics and low power factor caused by these

devices might damage the power quality and efficiency of the distribution

system. In this context it was felt necessary that a detailed study on the effect

of substantial induction of low quality compact fluorescent lamps in a rural

distribution system be carried out. This is the context of present study carried

out jointly by IRTC and KSEB.

2. SPECIFIC OBJECTIVES OF THE PROJECT

1. To conduct a series of laboratory investigations to measure the level of

high harmonics and low power factor of the low quality CFLs.

2. To conduct a real-time field study in a selected transformer in a typical

electrical major section to investigate the impact of high harmonics and

low power factor on the electrical distribution system.

3. To prepare technical recommendations and guidelines for formulating

policies regarding the propagation/popularisation of the energy efficient

lighting devices.

3. METHODOLOGY

The study was conducted in two phases,

1.The laboratory study.

2.The real time field study

The Poriyani 160 kVA transformer under Electrical Major Section, Kongad in

Electrical Division, Palakkad was selected for the investigation after


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consultations with the Deputy Chief Engineer, Palakkad. A 4kVA transformer

was made available for carrying out a laboratory test by simulating load

conditions

3.1. Laboratory Test

The laboratory test was conducted in the following phases.

1. Loading the test transformer with incandescent lamps, totaling to

wattage of about 3000 W in R, Y & B phases in balanced and

unbalanced conditions in different steps and combinations

2. Loading the transformer with compact fluorescent lamps totaling to a

wattage of 3000 W to R, Y & B phases in balanced and unbalanced

conditions in different steps and combinations

3. Taking different measurements in both cases, of the following

parameters

a. Level of current harmonics and distortion on the transformer

b. Level of voltage harmonics and distortion

c. Effect of heating on the core and winding of the transformer

d. Effect on the power factor of the system

e. Energy loss due to the lighting loadsf. Lumens/Watt

4. The load conditions of an ideal domestic consumer were simulated on

the lab transformer and all the relevant parameters were measured.

3.2. Real Time Field Study

The methodology for the detailed investigation in the field i.e.; on

Poriyani 160kVA transformer was finalised in consultation with experts in a

workshop held on 18-06-2003. In the discussions that followed KSEB

engineers provided the details of the existing consumers connected to the

transformer, which has two low tension distribution feeders. In the field the

study was carried out in the following phases


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1. Taking all the relevant readings at the transformer mains and

sending end terminals of feeders I & II in the existing load

conditions.

2. Taking all the relevant readings at two selected domestic consumerpremises connected to feeder II in the existing load conditions.

3. Replacing 190 incandescent lamps in 45 domestic premises

connected to feeder II.

4. Taking all the relevant readings at two selected domestic consumer

premises connected to feeder II after replacement of incandescent

lamps by CFLs.

5. Taking all the relevant readings at the transformer mains and

sending end terminals of feeders I & II after replacement of

incandescent lamps.

4. ANALYSIS OF TEST RESULTS

4.1. Laboratory Study

1.The Power factor of individual low cost CFLs is found to be very low in the

order of 0.5 to 0.6. (TABLE 1)

2.The power factor was found to improve as the total number of CFLs in thecircuit increased. (TABLE 2 -4)

3.The total harmonic distortion is high for the individual CFLs. (TABLE 1). But

THD decreased as the number of CFLs in the circuit increased. (TABLES 2

- 4)

4.Harmonics induced at the transformer primary was found to be much lesser

than that at the secondary. (TABLE 5)

5.Transformer loss was found to be higher for the CFLs compared to the

incandescent circuit of equivalent wattage (TABLE 5).

6.Due to the low power factor of the CFLs high current was drawn, higher

than the incandescent lamps for the same wattage. As a result the

temperature increase was greater for the CFL circuit but only three or four

degrees. (TABLES 6 & 7)


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7.Lumen per watt for the CFLs is much higher than that for the incandescent

lamps. There is no much variation in lumen out put even at system voltage

as low as 130 V, when CFLs are used (TABLE 8)

8.For the same lumen output much lesser power is consumed in the case ofCFLs and hence much lower current is drawn. Therefore the temperature

rise and the transformer loss would be ultimately reduced.

9.Load condition of a typical consumer was simulated in the lab. The load of

CFLs (39 W) is of smaller percentage of the total connected load (732 W

&2080 W with and without pump motor respectively). The power factor

improves considerably with motors and CFLs used concurrently in the

system (TABLE 9)

10. Waveforms distortions were very much higher at the test points due to

other loads such as television as compared to the addition of CFLs.

(TABLE 9)

4.2. Field study

1. Poriyani- II (160 kVA) transformer was selected for the field study. The

transformer is too under loaded (only around 60 kVA at peak hours) and

unbalanced to obtain an objective assessment of the impact of replacing

incandescent lamps with CFL on the transformer performance.

2.The power quality varied extensively from test point to test point due to

system fluctuations.

3.The nature of the waveforms at various test points depended mainly on the

load nature. The connected load at the two test points for different dates of

measurement is given in TABLE 11.

4.At the peak hours the power factor at the transformer was found to be unity

and the harmonics much lesser before the lamps were replaced.

5.As the incandescent lamps were replaced with the CFLs the power factor of

the system decreased only nominally, but the total harmonic distortion

increased noticeably. (TABLE 10 ,12 & 13)


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5. CONCLUSIONS

1.The field study revealed that the replacement of the existing incandescent

lamps with CFLs resulted in a reduction of load current (by 33 % in the LT

feeder under investigation). Calculation showed that the distribution loss in the

local network could be reduced substantially (about 40 % in the feeder

concerned).

2. The total power consumed by the CFLs to give the equivalent lumen

output will be less than 20 to 25 % of the power consumed by the

incandescent lamps. This reduces the total current in the transformer, thereby

reducing the transformer losses.

3.The effects of low power factor and high harmonics in the system by the

addition of the low quality CFLs were not found predominant in the rural

distribution system under investigation where electrical appliances of

heterogeneous nature such as TV, fridge, pumping motor etc. are connected.

The overall power factor was observed to fall from unity to 0.95 only. This is

not very much significant taking the overall system characteristic into

consideration.

4.Electrical appliances such as TV cause much more harmonic distortions

than by CFLs5. The present study is adequate to show,

a) For identical end use conditions (same or slightly improved illumination)

total replacement of incandescent lamps by CFLs doesnt cause

1) Any disturbance to the operation of other equipments like TV, radio,

computer etc.

2) Does provide comparatively more illumination at lower voltages as is

usual in Kerala rural areas.

3) The overall load current and hence line and transformer losses

come down. The actual value depends upon the original share of lighting load

in the system

4) When the transformer are fully loaded in kVA rating the active power

outputs will be lesser because of reduced power factor, but can serve more


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consumers because the power required by each for the same end use

services is reduced.

b) It will be, therefore, reasonable to argue that a total change over to CFLs in

the entire system can be thought of.

c) The next stage of the experiment could be to replace the incandescent

lamps in an overloaded section by CFLs at Electricity Boards expense and

observe the consequent reduction in load, reduction in the line losses and

work out the real economy of such a program.

It has been found the cheap CFLs are poorer in quality than the

costlier ones, not only in current quality and lumen output per watt, but also

with respect to the overall lifetime. 25 % of the lamps purchased failed before

they reached three hundred hours of total operation. The present estimation

based on the performance of remaining lamps is that average life will not be

more than 1000 hours, as compared to the normally claimed life of 6000

hours for good quality CFLs. A study of the failure mode of these cheap

imported CFLs might reveal some common features, which possibly can be

rectified with out considerable increase in cost. The following simple

calculation compares the economic performance of the cheap and high quality

CFLs for 6000 hours. The 60 W incandescent lamp, 10 W high quality CFL

and 15 W low quality CFL are having comparable lumen output.

Average unit cost of electricity = Rs 2.50

No. of hours of burning = 4 hours per day on an average

Expense for the three options for a period of 6000 hours

Incandescent

lamp (60 W)

High quality

CFL (10 W)

Low quality

CFL (15 W)

Life 1000 6000 1000

Cost per piece (Rs) 12 350 30

Capital cost (Rs) * 72 350 180

Interest 19 140 47

Energy consumption 360 60 90

Energy cost 900 150 225

Total expenditure 991 640 452


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* (Six replacements are to be made for incandescent lamp and low quality CFL)

For the consumer cheap CFLs work out cheaper, for identical lumen output.

From Electricity Boards point of viewCapital cost per watt delivered at consumer end = Rs 50. Distribution loss is

30% with incandescent lamps and 20 % with CFLs. To deliver 60 W at user

end 87 W has to be generated by the Board.

Savings due to the replacement of a 60 W incandescent bulb by high quality

and low quality CFLs having comparable lumen output

*(@ 20 % distribution loss)

Here the difference in the savings when using the high quality CFLs and the

low quality CFLs is only marginal.

6. RECOMMENDATIONS

1) Energy-efficient lighting devices like fluorescent tubes and Compact

Fluorescent Lamps (CFLs) have 6tob be promoted by the KSEB instead of

ordinary incandescent lamps.2) Energy-efficient lighting devices like fluorescent tubes and Compact

Fluorescent Lamps (CFLs) have to be distributed to the consumers at the

board's expense.

3) As the first step towards this and as the continuation of this study a typical

urban section and also a rural section have to be selected and the long term

High quality

CFL (10 W)

Low quality CFL

(15 W)

Wattage to be generated* 12.5 18.75

Savings in wattage 87-12.5 = 74.5 87-18.75 = 68.25

Savings in generation cost

@ Rs 50 / W3725 3412.5

Amount to be invested (Rs) 350 180

Net savings (Rs) 3375 3232.5


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implications has to be studied and also the quantitative analysis of the savings

made has to be made for a period of at least six months .

4) For maintaining the quality of the electric supply the KSEB has to begin

with those electronic equipment such as the television, UPS etc. whichproduce larger harmonic current in the electric distribution system

5) The active filters or the static compensators can be installed at the

transformer end or at the substation level to suppress the harmonic current

and also to improve the power factor of the system.

6) Advanced researches are to be promoted in this field.


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ANNEXE 1

TABLE 1

LABORATORY TEST RESULTS WITH CFLS

Brand V (V) I (mA) W (W) PF THD %-V THD %-I Harmonics

honey queen 220 73.00 9.40 0.59 3.229 101.983

3rd79.112

9th18.372

31st2.237

5th49.355

11th16.445

41st1.5

7th26.312

21st4.573

51st1.824

myota 220 63.40 7.72 0.56 3.272 78.133

3rd60.617

9th15.334

31st4.597

5th23.584

11th15.15

41st3.572

7th15.035

21st10.4

51st2.799

leuci 220 60.80 7.91 0.59 3.383 107.336

3rd81.195

9th14.636

31st4.988

5th

51.62211th

15.91341st

3.617th

22.8421st

9.83951st

2.758


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TABLE 2

LABORATORY TEST RESULTS WITH CFLS (added in 11 steps in single

phase)

STEP V I W PF THD %-V THD %-I Harmonics

1 222 2.83 339.00 0.54 4.625 119.2

3rd83.596

9th31.203

31st1.975

5th61.742

11th18.382

41st0.283

7th44.854

21st0.857

51st0.074

2 217 5.04 659.00 0.6 5.993 112.1

3rd84.485

9th20.393

31st0.635

5th59.619

11th10.117

41st0.338

7th36.252

21st1.104

51st0.162

3 218 6.83 970.00 0.65 6.597 98.09

3rd80.076

9th10.027

31st0.121

5th49.868

11th4.425

41st0.316

7th24.33

21st0.937

51st0.158

4 210 8.56 1220.00 0.68 7.871 90.92

3rd 77.5069th

4.8231st

0.2515th

44.097

11th

4.776

41st

0.1897th16.012

21st0.326

51st0.288

5 207 10.10 1460.00 0.7 9.318 86.67

3rd75.315

9th6.546

31st0.264

5th39.937

11th5.086

41st0.188

7th12.732

21st0.478

51st0.292

6 205 11.70 1740.00 0.72 9.571 75.26

3rd68.661

9th7.714

31st0.431

5th28.435

11th2.578

41st0.386

7th7.886

21st0.723

51st0.239

7 191 13.20 1860.00 0.74 9.221 71.79

3rd66.555

9th6.024

31st0.242

5th25.215

11th0.887

41st0.106

7th6.718

21st0.841

51st0.201

8 195 14.60 2160.00 0.76 10.593 70.59

3rd65.855

9th5.304

31st0.232

5th 24.174 11th 0.759 41st 0.1157th

5.17621st

0.74251st

0.046

9 192 16.10 2380.00 0.77 12.173 67.85

3rd64.056

9th5.489

31st0.171

5th21.165

11th1.431

41st0.184

7th3.747

21st0.524

51st0.035

10 195 17.90 2720.00 0.78 13.59 64.54

3rd61.621

9th1.845

31st0.232

5th17.769

11th1.127

41st0.176

7th4.287

21st0.245

51st0.06

11 191 19.70 2990.00 0.8 13.734 57.83

3rd55.916

9th3.363

31st0.244

5th10.913

11th2.2

41st0.17

7th8.518

21st0.59

51st0.153


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TABLE 3

LABORATORY TEST RESULTS WITH CFLS CONNECTED IN BALANCED

CONDITION

STEP 1V I W PF THD %-V THD %-I Harmonics

R 207 2.43 335.00 0.67 7.319 106.1

3rd84.317

9th7.931

31st0.61

5th56.596

11th3.745

41st0.523

7th28.213

21st1.561

51st0.404

Y 204 2.33 312.00 0.66 6.914 109.6

3rd85.258

9th11.24

31st1.644

5th59.233

11th3.621

41st0.471

7th32.203

21st1.231

51st0.23

B 200 2.28 291.00 0.64 6.369 108

3rd84.925

9th9.757

31st0.743

5th58.124

11th1.845

41st0.322

7th30.474

21st0.72

51st0.084

STEP 2

R 217 4.41 679.00 0.71 9.72 91.68

3rd77.522

9th5.4

31st0.437

5th45.098

11th5.455

41st0.336

7th17.188

21st1.145

51st0.326

Y 216 4.07 617.00 0.7 8.683 96.39

3rd79.981

9th6.022

31st0.524

5th48.871

11th5.839

41st0.428

7th20.198

21st1.264

51st0.253

B 214 4.15 614.00 0.69 8.123 95.14

3rd79.861

9th6.094

31st0.672

5th47.034

11th6.221

41st0.446

7th18.818

21st1.136

51st0.207

STEP 3

R 209 5.99 960.00 0.77 11.194 77.11

3rd

70.519th

5.17431st

0.3375th30.233

11th2.505

41st0.152

7th3.557

21st0.59

51st0.022

Y 205 5.68 876.00 0.75 10.045 79.39

3rd71.752

9th5.702

31st0.345

5th32.69

11th3.75

41st0.236

7th5.218

21st0.712

51st0.15

B 204 5.67 858.00 0.74 9.572 77.83

3rd70.746

9th5.254

31st0.468

5th31.499

11th2.578

41st0.585

7th3.986

21st0.417

51st0.036


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TABLE 4LABORATORY TEST RESULTS WITH CFLS CONNECTED IN UNBALANCEDCONDITION

V I W PF THD %-V THD %-I Harmonics

R 212 5.90 956.00 0.76 12.375 74.61

3rd68.629

9th6.049

31st0.28

5th28.012

11th2.847

41st0.264

7th4.057

21st0.602

51st0.155

Y 208 5.67 888.00 0.75 10.047 79.52

3rd71.877

9th6.4

31st0.376

5th32.544

11th3.774

41st0.15

7th5.744

21st0.593

51st0.141

B 219 2.55 323.00 0.63 5.324 105

3rd83.668

9th6.987

31st0.507

5th56.095

11th3.508

41st0.77

7th27.774

21st1.16

51st0.446

STEP 2

R 212 6.09 976.00 0.76 11.293 74.65

3rd68.755

9th5.512

31st0.467

5th28.004

11th3.036

41st0.389

7th2.245

21st0.609

51st0.289

Y 203 5.65 847.00 0.74 10.156 80.69

3rd72.459

9th4.954

31st0.592

5th34.111

11th3.518

41st0.182

7th6.804

21st0.952

51st0.059

B 210 4.10 597.00 0.69 7.805 89.8

3rd77.25

9th2.108

31st0.345

5th43.162

11th4.597

41st0.165

7th13.747

21st0.78

51st0.223

STEP 3

R 209 5.99 960.00 0.77 11.194 77.11

3rd70.51

9th5.174

31st0.337

5th 30.233 11th 2.505 41st 0.1527th

3.55721st

0.5951st

0.022

Y 205 5.68 876.00 0.75 10.045 79.39

3rd71.752

9th5.702

31st0.345

5th32.69

11th3.75

41st0.236

7th5.218

21st0.712

51st0.15

B 204 5.67 858.00 0.74 9.572 77.83

3rd70.746

9th5.254

31st0.468

5th31.499

11th2.578

41st0.585

7th3.986

21st0.417

51st0.036

STEP 1


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TABLE 5

LABORATORY TEST RESULTS WITH CFLS AND INCANDESCENT LAMPSTransformer loss and primary & secondary harmonics

WITH CFL ALONE (33 NUMBERS)

PRIMARYTOTALINPUT SECONDARY

TOTALOUTPUT

PERCENTAGELOSS

R Y B R Y B

5.24

VOLTAGE 229 229 224 235 236 232

CURRENT 2.09 2 2.02 2.58 2.39 2.42

WATT 380.974 366.4 362.44 1109.81 373.481 345.19 332.934 1051.607

PF 0.796 0.8 0.801 0.616 0.612 0.593

THD % V 2.184 2.095 2.859 5.789 5.834 4.466

ITHD % I 64.148 72.883 63.676 107.92 108.61 111.539

WITH INCANDESCENT LAMP ALONE

R Y B R Y B

1.04

VOLTAGE 224 207 213 231 231 229

CURRENT 1.69 1.68 1.6 1.58672 1.5039 1.49342

WATT 378.56 347.76 340.8 1067.12 366.532 347.4 341.993 1055.922

PF 1 1 1 1 1 1

THD % V 2.805 2.204 4.312 2.24 2.843 2.885

THD % I 2.599 2.363 3.292 2.203 2.885 2.308


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TABLE 6LABORATORY TEST

TRANSFORMER TEMPERATURE WITH CFL ALONE: Total wattage = 1052(Power parameters given in TABLE 5)

TIME CORE TEMP (

o

C) WINDING TEMP (

o

C)0:00 28 28

0:10 29 30

0:20 30 32

0:30 31 33

0:40 32 34

0:50 33 36

1:00 34 37

1:10 34 37

1:20 35 38

1:30 36 39

1:40 36 39

1:50 37 402:00 37 40

2:10 38 41

2:20 38 41

2:30 39 42

2:40 40 42

2:50 40 42

3:00 40 42

TEMPERATURE VERSUS TIME PLOT FOR CFL CIRCUIT

0

10

20

30

40

50

0:00

0:30

1:00

1:30

2:00

2:30

3:00

CORE

TEMP

WINDING

TEMP


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21

TABLE 7LABORATORY TEST

TRANSFORMER TEMPERATURE WITH INCANDESCENT LAMP ALONE:Total wattage = 1056

(Power parameters given in TABLE 5)

TIME CORE TEMP (oC) WINDING TEMP (

oC)

0:00 28 28

0:10 30 31

0:20 31 31

0:30 31 32

0:40 32 33

0:50 33 33

1:00 34 34

1:10 34 35

1:20 35 35

1:30 35 36

1:40 36 36

1:50 36 372:00 37 37

2:10 37 37

2:20 37 37

2:30 37 37

2:40 37 37

2:50 37 37

3:00 37 37

TEMPERATURE VERSUS TIME PLOT FOR INCANDESCENT LAMP CIRCUIT

0

10

20

30

40

0:00

0:30

1:00

1:30

2:00

2:30

3:00

CORETEMP

WINDING

TEMP


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22

TABLE 8MEASUREMENT OF LUMEN PER WATT WITH DIFFERENT MAKES OF CFLS AND

INCANDESCENT LAMPS

LUMEN PER WATT at

230 V 210 V 190 V 170 V 150 V 130 V

LOW COST

HONEY QUEEN 4.6 4.7 4.66 4.57 4.52 4.36

MYOTA 3.71 3.48 3.38 3.15 2.9 2.32

LEUCI 4.61 4.57 4.38 4.27 4.31 4.1

HIGH COST13 W (PARISHAD) 6.26 6.27 6.15 6.02 5.71 5.11

11 W (PARISHAD) 5.53 5.46 5.33 5.08 4.53 4.19

INCANDESCENT

100 W 1.16 0.98 0.82 0.65 0.52 0.43

60 W 0.91 0.76 0.63 0.51 0.39 0.29

40 W 1.05 0.89 0.7 0.61 0.43 0.35

TABLE 9SIMULATION OF A DOMESTIC CONSUMERS LOAD AT THE LABORATORY USING CFLS

AND INCANDESCENT LAMPS ALONG WITH DIFFERENT ELECTRICAL APPLIANCES

FRIDGE

2 FAN TV300 W

INCLAMP

4 CFLS MOTOR

FRIDGE +2FAN+TV

+300WINC LAMP

FRIDGE+2FAN+TV+

4CFLS

FRIDGE+2FAN+TV+300W INCLAMP+MOTOR

FRIDGE+2

FAN+TV+4CFLS+

MOTOR

V (V) 209 209 220 219 225 216 222 222 209 213

I (A) 1.17 0.67 0.4 1.334 0.23 6.73 3.36 2.3 9.9325 8.7375

W (W) 173.372 139.89 67.32 292.146 38.502 1452.23 731.747 486.091 2079.95 1753.9

pf 0.709 0.999 0.765 1 0.744 0.999 0.981 0.952 0.998 0.994Fundamentalcurrent

(A)

1.168 0.674 0.309 1.332 0.197 6.719 3.342 2.277 9.926 8.718

THD%V

3.053 4.775 4.382 2.053 1.753 1.538 1.885 2.741 2.048 2.018

THD %I

4.24 6.312 78.049 2.084 60.493 3.477 9.117 14.355 2.643 3.114


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23

TABLE 10FIELD TEST READINGS - BEFORE REPLACEMENT OF INCANDESCENT LAMPS WITH

CFLS

Test Point No.1

Date V I W PFTHD %-

V

THD %-

I

Harmonics

5-Mar-04 202 1.56 307.00 0.98 1.985 15.42

3rd10.649

9th2.975

31st0.74

5th7.685

11th1.776

41st0.396

7th6.582

21st0.989

51st0.261

6-Mar-04 201 1.35 259.00 0.96 2.245 19.071

3rd12.658

9th2.71

31st0.313

5th10.434

11th0.933

41st0.532

7th8.194

21st0.864

51st0.365

7-Mar-04 200 1.99 389.00 0.98 2.326 15.287

3rd10.419

9th2.567

31st0.29

5th7.959

11th1.033

41st0.313

7th6.607

21st0.558

51st0.232

Test Point No.2Date V I W PF Thd.V% Thd.I% Harmonics

5-Mar-04 218 1.99 432.00 1 3.215 2.961

3rd1.879

9th0.303

31st0.102

5th2.143

11th0.026

41st0.107

7th0.352

21st0.114

51st0.008

6-Mar-04 201 2.25 452.00 1 2.685 2.431

3rd0.688

9th0.28

31st0.023

5th2.185

11th0.166

41st0.031

7th0.489

21st0.155

51st0.043

7-Mar-04 203 0.89 179.00 0.99 2.433 2.059

3rd0.452

9st0.302

31st0.047

5th1.797

11th0.07

41st0.029

7th0.624

21st0.043

51st0.032

FIELD TEST READINGS -AFTER REPLACEMENT OF INCANDESCENT LAMPS WITH CFLS

Test Point No.1

Date V I W PFTHD %-

VTHD %-

IHarmonics

8-Mar-04 199 2.90 497.00 0.86 2.86 31.39

3rd 24.729 9st 4.117 31st 0.6855th

13.25911th

2.38341st

1.0427th

11.65621st

0.81251st

0.935

9-Mar-04 202 2.15 351.00 0.85 2.637 26.188

3rd20.643

9st4.493

31st0.633

5th10.095

11th0.854

41st0.875

7th10.266

21st0.291

51st0.68

10-Mar-04 201 1.56 301.00 0.96 2.157 18.985

3rd14.274

9st4.882

31st0.382

5th6.051

11th0.217

41st0.733

7th9.063

21st0.256

51st0.717

Test Point No.2Date V I W PF Thd.V% Thd.I% Harmonics

8-Mar-04 212 0.72 146.00 0.96 3.595 20.348

3rd10.146

9st8.22

31st0.48

5th 9.872 11th 5.347 41st 1.0087th

9.55121st

1.32151st

0.533

9-Mar-04 198 0.80 269.00 0.98 3.596 20.755

3rd12.17

9st7.482

31st0.532

5th10.282

11th5.32

41st0.411

7th7.742

21st2.069

51st0.347

10-Mar-04 213 0.64 130.00 0.95 3.262 23.806

3rd12.999

9st9.131

31st0.45

5th10.912

11th6.106

41st0.588

7th10.595

21st1.993

51st0.769


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24

TABLE 11

FIELD TESTConnected load in the premises of test point 1 and 2 as on dates of measurements

5/3/04 6/3/04 7/3/04 8/3/04 9/3/04 10/3/04

TESTPOINT 1

FAN X 2 FAN X 2 FAN X 1 FAN X 2 FAN X 3 FAN X 2

40 W IL X 1 40 W IL X 1 60 W IL X 2 CFL X 3 CFL X 5 CFL X 2

60 W IL X 3 60 W IL X 3

100 W IL X 1 100 W IL X 1

TESTPOINT 2

FRIDGE FRIDGE FRIDGE FRIDGE FRIDGE FRIDGE

FAN X 1 FAN X 1 FAN X 2 FAN X 3 FAN X 2 FAN X 2

TV TV TV TV TV TV

FLUORESCENT LAMP X 1




FLUORESCENT LAMP X 1 CFL X 3

60 W IL X 1 60 W IL X 1 CFL X 5 CFL X 4

TABLE 12FIELD TEST READINGS AT THE TRANSFORMER END BEFORE THE REPLACEMENT

Date Phase V I W PF Thd.V% Thd.I% Harmonics

5-Mar-04

R 223 26.50 5900.00 1 2.372 3.264

3rd2.273

9st0.146

31st0.051

5th2.263

11th0.084

41st0.025

7th0.309

21st0.146

51st0.033

Y 217 10.40 2190.00 0.97 2.241 6.711

3rd5.306

9st2.712

31st0.203

5th0.501

11th1.735

41st0.05

7th1.985

21st0.032

51st0.331

B 217 12.20 2620.00 0.99 2.411 6.638

3rd5.758

9st1.408

31st0.188

5th1.826

11th0.682

41st0.085

7th

1.97721st

0.34351st

0.15Date Phase V I W PF Thd.V% Thd.I% Harmonics

6-Mar-04

R 214 31.40 6690.00 1 2.533 5.264

3rd4.072

9st0.952

31st0.055

5th1.999

11th0.389

41st0.053

7th1.955

21st0.228

51st0.057

Y 210 1.10 2320.00 1 2.375 7.243

3rd4.739

9st2.635

31st0.184

5th3.807

11th1.799

41st0.061

7th1.95

21st0.351

51st0.035

B 210 16.50 3440.00 1 2.265 5.021

3rd3.886

9st1.46

31st0.27

5th1.747

11th0.704

41st0.128

7th1.604

21st0.381

51st0.129


7-Mar-04

R 209 33.20 6920.00 1 2.389 3.314

3rd

2.9629st

0.08631st

0.0085th

1.23511th

0.23441st

0.0117th

0.58421st

0.0951st

0.074

Y 206 13.60 2790.00 1 2.1 2.841

3rd1.318

9st1.105

31st0.076

5th1.3

11th1.412

41st0.017

7th0.505

21st0.036

51st0.118

B 206 17.10 3510.00 1 2.139 4.239

3rd3.099

9st1.204

31st0.092

5th1.683

11th0.668

41st0.064

7th1.658

21st0.12

51st0.051


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25

TABLE 13FIELD TEST READINGS AT THE TRANSFORMER END AFTER THE REPLACEMENT


8-Mar-04

R 209 17.70 3560.00 0.96 2.298 21.87

3rd17.94

9st3.521

31st0.106

5th 10.57 11th 0.905 41st 0.127th

5.40521st

0.23351st

0.014

Y 205 9.26 1840.00 0.97 2.176 9.792

3rd7.347

9st1.971

31st0.073

5th5.436

11th0.356

41st0.101

7th2.57

21st0.247

51st0.037

B 205 9.78 1940.00 0.97 2.226 25.75

3rd21.31

9st9.301

31st0.105

5th3.138

11th4.369

41st0.133

7th9

21st0.681

51st0.118


9-Mar-04

R 213 16.80 3410.00 0.95 2.167 26.45

3rd21.58

9st4.069

1.5420.173

5th12.35

11th1.542

41st0.094

7th7.667

21st0.044

51st0.14

Y 207 9.15 1870.00 0.99 2.236 11.71

3rd8.335

9st4.048

31st0.224

5th3.595

11th2.309

41st0.703

7th5.109

21st0.195

51st0.252

B 208 10.90 2200.00 0.97 2.185 26.05

3rd22.5

9st8.728

31st0.166

5th3.491

11th4.662

41st0.335

7th7.055

21st0.677

51st0.1


10-Mar-04

R 209 17.50 3480.00 0.97 2.318 22.36

3rd18.44

9st4.173

31st0.147

5th9.976

11th1.388

41st0.224

7th6.181

21st0.285

51st0.165

Y 204 8.34 1650.00 0.97 2130 14.16

3rd10.97

9st3.538

31st0.147

5th

5.282

11th

860

41st

0.4667th5.469

21st0.605

51st0.764

B 205 9.94 1960.00 0.96 2.267 27.74

3rd23.84

9st8.845

31st0.188

5th2.005

11th3.319

41st0.658

7th9.454

21st0.229

51st0.314

TABLE 14

FIELD TEST NO. OF INCANDESCENT LAMPS REPLACED IN FEEDER 2 OF PORIYANI160 KVA TRANSFORMER

FEEDER 140 W 60 W 100 W

NO. OF LAMPS REPLACED 63 109 18190

TOTAL W2520 6540 1800

10860

Number of CFLs placed = 190

Total watts = 1900


26/31

26

ANEXE 2

VOLTAGE AND CURRENT WAVEFORMS(Channel 1shows the voltage waveform and channel two shows the current

waveform)

1. LAB STUDY

1.1. ADITION OF CFLS IN 11 STEPS (REFERENCE TABLE 1)

STEP 1

STEP 4


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27

STEP 7

STEP 11


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28

2. FIELD STUDY

2.1. TEST POINT 1(REFERENCE TABLE 10)

BEFORE REPLACEMENT OF INCANDESCENT LAMPS

AFTER REPLACEMENT


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29

2.2. TEST POINT 2 (REFERENCE TABLE 10)

BEFORE REPLACEMENT

AFTER REPLACEMENT


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30

2.3. TRANSFORMER POINT (REFERENCE TABLE 12)

BEFORE REPLACEMENTR PHASE

Y PHASE

B PHASE


31/31

AFTER REPLACEMENTR PHASE

Y PHASE

B PHASE

harmonics study on distrubution transformer

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