hvdcseminarbybe12f03f025-150416125641-conversion-gate01.pdf

Ggh

1. A
SEMINAR ON
“HVDC TRANSMISSION ”
SUBMITTED
BY
Utkarsh J. Jambhule
(BE12FO3FO25)
UNDER THE SUPERVISION OF
Dr. Archana G. Thosar (H.O.D)

2. INTRODUCTION:
With the increasing of requirement of electrical power
supply the facilities have to be increased in that
transmission plays an important role.
Here HVDC (high voltage direct current) transmission
plays major role in power transmission.
First HVDC transmission linked between gotland and
mainland in sweden in 1954.
The HVDC transmission has many advantages over
HVAC transmission.

3. HVDC MEANS…..
HVDC stands for High Voltage Direct Current and is
today a well-proven technology all over the world.
Two AC systems having different frequencies can be
linked up together by means of HVDC link.
HVDC technology is used to transmit electricity over
long distances.

4. WHY DC TRANSMISSION ?
Losses are less in DC transmission while comparing to
AC transmission.
Only two conductors are required for DC with
positive and negative polarities.
DC overhead lines or cables are less
expensive.
DC lines are useful for long distances above
500km.
?

5. Comparison of HVAC and HVDC
Conventionally power transmission is affected
through HVAC systems all over the world.
 HVAC transmission is having several limitations like,
line length , uncontrolled power flow, over/low voltages
during lightly / over loaded conditions, stability
problems, fault isolation etc…
 But HVDC have low transmission losses and it
requires only two conductors.

6. Comparison between the prices of AC & DC
Transmission

7. Wind
Power
AC
Transmission
Line
Converter
Station
Inverter
Station
AC
Transmission
Line
Distribution
Line
HVDC
Transmission Line
HVDC transmission system

8. 1.Converters
2.Smoothingreactors
3.Harmonicfilters
4.Reactivepowersource
5.Electrodes
6.Dclines
7.Accircuitbreakers

10. Homopolar link
Monopolar link
Bipolar link
HVDC Transmission can be broadly classified
into:-

11. Itusesoneconductor.
Thereturnpathisprovidedbygroundorwater.
Useofthissystemisduetocostconsiderations.
Ametallicreturnmaybeusedwhereearthresistivityistoohigh

12. Eachterminalhastwoconvertersofequalratedvoltage,
connectedinseriesonDCside.
Thejunctionsbetweenconvertersisgrounded.
Ifonepoleisisolatedduetofault,theotherpolecanoperate
withgroundandcarryhalftheratedload(ormoreusing
overloadcapabilitiesofitsconverterline.)

13. Ithastwoconductorseachhavingsamepolarity,usuallynegative.
SincethecoronaeffectinDCtransmissionlinesislessfor
negativepolarity,homopolarlinkisusuallyoperatedwithnegative
polarity.
Thereturnpathforsuchasystemisthroughground.

14.  Back to Back Transmission.
 Point to point Overhead line
Transmission.
 Point to point Underground Cable
Transmission.
 Point to point Sub marine
Transmission.

19. The losses which occurs in the
systems are comparatively low at all the
stages (i.e.) at generation , transmission
& distribution level.
The losses at transmission level can
be highly reduced by HVDC
transmission.

20. Advantages of HVDC
Technical
Advantages
Economic
Advantages

21. LesserCoronaLossandRadiointerference.
Thevoltageregulationproblemismuchless
seriousforDC,sinceonlytheIRdropis
involved.Forthesamereasonsteadystate
stabilityisnolongeramajorproblem.
NoskinandproximityandFerrantieffect
Asynchronousoperationpossiblebetween
regionshavingdifferentelectricalparameters.

22. DClinesandcablesarecheaperthanAClines
orcables.
ThetowersoftheDClinesarenarrower,
simplerandcheapercomparedtothetowersof
theAClines.
LinelossesinaDClinearelowerthanthe
lossesinanAClines.

23. ThedisadvantagesofHVDCareinconversion,
switching,control,availabilityandmaintenance.
ThereisnothinglikeDCtransformerwhichcan
changethevoltagelevelinasimpleway.Voltage
transformationhastobeprovidedontheACsidesof
thesystem.
Therequiredconverterstationsareexpensiveandhave
limitedoverloadcapacity.

24. Rihand-delhi and chandrapur-padghe were the first long
distance hvdc projects in India.
In 1990 ,rihand-delhi (singrauli) thermal power complex
with a combined power generation of Several thousand
MW was put in to service.it covers over a distance of 814
km.
The 1500 MW transmission chandrapur-padghe was put
in to service.it covers over distance of 736 km.
APPLICATIONS OF HVDC TRANSMISSION IN INDIA:

25. Conclusion
RecentstudiesindicatethatHVDCsystemsarevery
reliable.
VerylargeinvestmentsEg.InChinaandIndiashowsthat
HighVoltageDirectCurrentwillveryimportantinthe
future,especiallyinbigandnew-industriescountries.

26. 1.C.L.wadhwa ‘electrical power systems'-third edition
2. I.J.nagrath and d.p.khotari 'power system engineering
3. S.S. vadhera 'power system analysis and stability
4. Soni gupta bhatnagar 'power system engineering
5. K.R.padiyar ‘hvdc power transmission systems'
BIBLIOGRAPHY: