Mr. Satish Kumar Director (Elect.), Delhi Metro Rail Corporation Ltd. (DMRC) currently is also a Govt. of India nominee on the Boards of Bangalore Metro Rail Corporation & Chennai Metro Rail Corporation. He is a former officer of the Indian Railway Service of Electrical Engineers and has over 45 years of professional experience and is one of the main persons behind the success of Delhi Metro Rail Project today.

Having been associated with this project right since its inception in 1998, for about 15 years Mr. Kumar has contributed immensely towards the introduction of the state of the art technologies in the Delhi Metro systems – Rolling Stock, Signalling, AFC etc., which has revolutionized the mass transport scenario of the national capital. He has also been Director incharge of operation and maintenance of Delhi Metro in its initial years upto 2005.

He has been conferred with many awards during the last 10 years, recent being the “Lifetime Achievement Award” by the Institution of Engineers (India) Delhi State Centre on 19th Jan 2013.

Satish Kumar Director

Delhi Metro Rail Corporation

Design of Power Supply system for 527km High Speed Rail Line (300kmph)

between Thiruvananthapuram & Kasargod

By Satish Kumar, Director/Electrical Mahendra Kumar, Chief Elect. Engineer

International Seminar on High Speed Trains

Dated:01/02/2013

Contents

1. Salient Features of Route2. Power supply arrangements

• Selection of Traction System•Selection of catenary system

• Auxiliary Power Supply System3. Conclusions

Salient Features

•Route Length - 527 Kms

At Grade 87 KmsElevated 297 KmsBridges (Waterway width) 17 KmsUnderground 126 KmsTotal 527 Kms

Station Name Inter Station Distance (Kms.)

1 Thiruvananthapuram 2 Quilon 573 Changannur Future

Station52

4 Kottayam 31 (83) 5 Erankulam 536 Trissur 657 Tirur Future Station 568 Calicut 46 (102)9 Thalessery Future Stn 62

10 Kannur 17 (79)11 Kasaragod 86

Stations with Inter Station Distance

Train Operation• Peak Period

•Off Peak Period

•15 minutes from 08.00hrs to 11.00hrs & 17.00hrs to 21.00hrs.

• In non-peak hours the train at interval of 30 minutes.

Speed

a) Operational Speed

b) Maximum Design Speed

c) Average Speed

300 KMPH

350 KMPH

250 KMPH (8 stations)

• Train Set

• Power per train

10 Coaches

10 MW

Selection of the Traction System

•1500V DC system•AC system

•25 kV ac •2X25 kV

Worldwide High Speed Railways have adopted

25kV ac system or 2X25kV AC Auto transformer

system

25kV ac system

• The system supplies power to the train-sets through 25kV ac overhead system. Current returns through the rail and the ground. The voltage between contact wire and rail is 25kV.

• The voltage variation permitted as per EN 50163/ IEC 60850 is as below;

Minimum(just for 10 min)

minimumPermanent

nominal MaximumPermanent

Maximum(just for 5min)

17.5kV 19kV 25kV 27.5kV 29kV

Mitigation of electromagnetic interferences (emi)

Booster Transformers are installed in series in the catenary, to reduce electromagnetic interferences.

These have limitations to mitigate the impact fully especially in case of failure of a few booster transformers.

It can have adverse effect on neighboring telecom system.

A typical arrange of 25 kV with Booster transformer

2X25kV ac single phase Auto transformer system

• This also supplies power to trains at 25kV ac but has transmission system of 50kV by Auto transformer system.

• 50kV is formed between the catenary, and a conductor called the ‘feeder

• Catenary and feeder are supported on the same pole on the same track.

• The transmission line so formed is coupled electrically to the catenary-rail loop via the auto transformers, which transforms this double voltage (50kV) into 25kV voltage for trains.

• This system of auto transformer traction power supply system was first used in 1972 by the Japanese railways on the SANYO lines with the main objective of improving emi as compared to BT system.

• It is learnt that France adopted 2X25kV ac Auto transformer system primarily from the point of view of reducing the emi and also the line losses.

It has other benefits compared to 1x25kV ac as under

• For equal volumes of traffic, the line voltage drops gets reduced by more than 2 to nearly 3,

• Reduce the number of neutral sections

• It gives flexibility to position the substations better with respect to existing grid lines

• Discontinuity is not experienced in the contact wire as in the BT system.

In short electrical aspects of 1x25kV & 2x25kV are

1X25 2X25Train voltage 25 kV 25 kV@line voltage drops v v/3line currents a a/2electrical loss (I square R)

w w/4

disturbance e over e/2

Continuity in normal conditions

4 to 25kmneutral section sectioning post

(booster transformer)

25 to 80km

Note: @-reduces the number of substation

Typical Impedance for 2X25 ac system

0.3 Ω per km using 1X25kV,0.12 Ω per km using 2X25kV

Accordingly 2X25kV Auto-transformer system has been proposed for Kerala High Speed line

Selection of the Catenary System

• Proper current collection at high speed by panto of train through contact wire is the main consideration.

Three types of 25kV ac catenary systems have been used world over

Compound type,

Y-stitch type and

Simple type

Compound Catenary systemCompound system for HSR was evolved in Japan for first

bullet train Shinkansen in 1964.This system has a second catenary wire, called the

auxiliary catenary wire between the main catenary wire and the contact wire. It is joined to the main catenary wire and the contact wire by means of droppers which helps to reduce variations.

However, the good current collection characteristics of this type of installation are offset by the increased material requirements and significant higher installation effort.

Compound Catenary system

• Latest compound catenary systems in operation is Taiwan-shinkansen

Y-stitch Catenary system

• A y-stitch wire is used to designate a connecting element inserted between the catenary wire and the contact wire.

• Sicat H1.0 was used for HSR 300km/h in operation between Cologne and Frankfurt.

• German rail has developed Y-stitch catenary system for conventional lines also

Simple Catenary system

Simple catenary system with higher size conductors, heavier tension and a pre sag (of1/1000 of span) is reported to be adequate for speeds upto 350 kmph.

France• ‘TGV Atlantic line’ commissioned in 1989 with

commercial speed of 300km/h. • TGV- Nord in 1993, •TGV- Mediterranean in 2001,

Korea•KTX- Kyungbu line in 2004. •TGV-est commercial speed of 350km/h.

• Korea’s Kyungbu HSR line with a commercial speed up to 310km/h,

In short, main characteristics of the three systems areKTX-Kyungbu [Korea], TGV-Nord [French

Sicat H1.0 [German](Y- Stitch)

Taiwan-Shinkansen, [Japan] (Compound

Catenary Type Simple Y-stitch Compound

Operation Speed 300km/h (Over) 300km/h 300km/h

Contact Wire Cu150sqmm CuMg 120sqmm

CuSn 170sqmm

Tension 20kN 27kN 20kN

Conductivity of Contact wire 98[%] 74.5 70[%]

Mass- contact 1.334[kg/m] 1.07[kg/m] 1.511[kg/m]

Auxiliary Contact wire - - Cu 150sq mm[15kN]

Conductivity of Aux. Contact wire - - 98[%]

Messenger wire Tension 14kN 21kN 25kN

mass ofmessenger wire

0.605[kg/m] 1.022[kg/m] 1.450[kg/m]

Conductivity of messenger wire

60[%] 60[%] 17.2[%]

Total surface of conductors

186sq mm 161.4sq mm 296sq mm

Dropper Bz 12sq mm Bz 16sq mm hanger

stagger 200mm 300mm 300mm

Maximum Span 63m 70m 60m

Height 5.08m 5.3m 5.0m

Simple type of catenary has been proposed for

Kerala High Speed rail

Auxiliary power supply system (APSS) for the stationsReliable Auxiliary power is required for HSR for: signal and telecommunication, fire prevention, tunnels, stations, depots, bases, facilities, substations, SP, PP, RTU CCTV, maintenance point, etc. Commercial development on route

Typical Design for APSS:Reliability & availability assume equal importance. It can be achieved through two ways;Using traction powerLaying separate power transmission line from

the grid substations at 110 kV or 66kVand

stepping it to down to 33kV or 11 kV for distribution through the cable network.

A Typical concept for APSS

Conclusion• From the techno-economical consideration it is

proposed to go in for 2X25 kV traction system for the Thiruvananthapuram - Kasargod High Speed line

• The power to the train is at 25 kV, ac, 50 Hz, single phase supply.• Simple catenary is proposed.

• The Auxiliary Power supply system, power at the passenger stations shall be taken from the grid substations, stepped down at 33 kV or 11 kV and distributed through a cable network.

• Concrete viaduct not being good conductor of electricity Earthing and Bonding arrangements will be designed specially.

Thanks for Attention