• modelling of the electric railway system including locomotives; • influence of the electric railway system on power quality in the transmission system simulations and power quality measurements); • modelling of reactive power compensation for electric railway systems and analysis of switching transients; • influence of the electric railway system on pipelines and telecommunication cables.

1. 1
User Group 2016
Aix-en-Provence, France
9th - 10th June 2016
MODELLING OF 25 kV ELECTRIC RAILWAY
SYSTEM IN EMTP-RV
Prof. Ivo Uglešić, PhD
Božidar Filipović-Grčić, PhD
Faculty of Electrical Engineering and Computing
University of Zagreb, Croatia

2. Presentation outline
The presentation will discuss the following issues:
• modelling of the electric railway system including
locomotives in EMTP-RV software;
• influence of the electric railway system on power
quality in the transmission system (simulations and
power quality measurements);
• modelling of reactive power compensation for electric
railway systems and analysis of switching transients;
• influence of the electric railway system on pipelines
and telecommunication cables.

3. Modelling of the electric railway system
including locomotives
&
Influence on power quality in the
transmission system
(simulations and measurements)

4. 110 kV
25 kV
110/25 kV
L1
L3
L2
Connection of the electric railway system to power
transmission network

5. Electric traction substation 110/25 kV

6. Contact network, 25 kV (50 Hz)

7. Contact network, 25 kV (50 Hz)
Catenary wire Catenary wire
Contact wire
Rails

8. • The electric railway system including locomotives equipped with
diode rectifiers was modeled using EMTP-RV software.
• The influence of the electric railway system on power quality in
110 kV transmission system was analyzed.
• Currents and voltages were calculated in 25 kV and 110 kV
network.
Modelling of 25 kV Electric Railway System for Power
Quality Studies

9. Model in EMTP-RV
• A model consists of electric railway substation and contact
line feeding electric locomotives equipped with diode
rectifiers.
• An electric locomotive with diode rectifiers consists of
locomotive transformer 25/1.06 kV, diode rectifier bridges
and four DC motors.
Model in EMTP-RV software which was used for
analysis of electromagnetic transients
DC motors
20 kV, 50 Hz contact line
system and rails
Diode rectifier
bridges
Locomotive transformer 25/1.06 kV
Traction substation
transformer 110/25 kV,
7.5 MVA
Equivalent of the
transmission network 110 kV
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV5
LINE DATA
kontaktna_mreza
model in: kontaktna_mreza_rv.pun
870 DC2
+
0.027,5.033mH
?iRL9
870 DC3
+
0.027,5.033mH
?iRL10
870 DC4
+
0.027,5.033mH
?iRL11
870 DC5
+
0.027,5.033mH
?iRL14
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV1
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV3
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV6
FD+
FDline2
+
1 2
Tr0_5
0.22727272727272726
VM+
m15
?v
+ A
m19
?i
s2+
s2
s3+
s3
s4+
s4
p+
p-
+
4.5,15.9mH
RL21
+
11
R18
+
50
L6
+
0.004,28.58uH
RL22
+
0.004,28.58uH
RL23
+
0.004,28.58uH
RL24
+
0.004,28.58uH
RL25
Ideal
transformer
25
p+
p-
1060 s1+
s1
1060 s2+
s2
1060 s3+
s3
1060 s4+
s4
25kV
Tr0_6
s1
s1+
+
AC3
110kVRMSLL /_0
VM+
m13?v
+
RL27
+ A
m23
?i
+
RL26
0.5,4mH
c
b
BUS2

10. Diode bridge rectifier
+
7.5
R1
+
1.33uF
C2
+
7.5
R2
+
1.33uF
C3
+
7.5
R3
+
1.33uF
C4
0.7
0
?viD5
0.7
0
?viD6
0.7
0
?viD7
+
7.5
R4
+
1.33uF
C5
0.7
0
?vi
D8
+
0.001
R5
+
0.001
R6
+
0.001
R7
+
0.001
R8
+
125uF
?v
C6

11. Current waveform at 25 kV side of railway
substation transformer
Voltage waveform at 25 kV side of railway
substation transformer
Current and voltage waveforms at 25 kV level

12. Current waveforms at 110 kV side of
railway substation transformer
Voltage waveforms at 110 kV side of
railway substation transformer
Current and voltage waveforms at 110 kV level

13. Current and voltage harmonics at 110 kV level
Voltage harmonics at 110 kV side of railway
substation transformer
Current harmonics at 110 kV side of railway
substation transformer

14. Voltage THD U THD I
110 kV 1.63 %
41.83 %
25 kV 2.06 %
Calculated current and voltage THD at
110 kV and 25 kV
Harmonic
number
25 kV 110 kV
U (V) I (A) U (V) I (A)
1st 35280 194 89560 40.1
3rd 125.1 35.2 251.2 11.4
5th 116.7 31.0 234.4 6.4
7th 107.7 10. 5 216.4 4.2
21st 421.0 26.7 931.4 5.5
23rd 462.0 26.7 841.8 5.5
Current and voltage harmonics
Calculated current and voltage harmonics and THD

15. 110 kV
35 kV 35 kV
110 kV transmission
line - Gojak 1
110 kV transmission
line - Gojak 2
TR 1 TR 2
110/35 kV
Yy0
20 MVA
110/35 kV
Yy0
20 MVA
TR 1
7,5 MVA
TR 2
7,5 MVA
PQ1 PQ2
PQ3 PQ4 PQ6 PQ7
Electric railway system
110 kV transmission
line
110 kV transmission
line
Power quality measurements

16. 0,00
0,20
0,40
0,60
0,80
1,00
1,20
1,40
1,60
1,80
2,00
2009-vlj-03
00:00:00, uto
2009-vlj-04
00:00:00, sri
2009-vlj-05
00:00:00, čet
2009-vlj-06
00:00:00, pet
2009-vlj-07
00:00:00, sub
2009-vlj-08
00:00:00, ned
2009-vlj-09
00:00:00, pon
2009-vlj-10
00:00:00, uto
%Un
Uh3 RMS L1 10' Uh3 RMS L2 10' Uh3 RMS L3 10'
0,00
0,20
0,40
0,60
0,80
1,00
1,20
1,40
1,60
1,80
2,00
%Un
Uh3 RMS L1 10' Uh3 RMS L2 10' Uh3 RMS L3 10'
(%)ofthe1st
harmonic
Date and time
Power quality measurements
3rd voltage harmonic at 110 kV level

17. 0,00
1,00
2,00
3,00
4,00
5,00
6,00
7,00
8,00
2009-vlj-03
00:00:00, uto
2009-vlj-04
00:00:00, sri
2009-vlj-05
00:00:00, čet
2009-vlj-06
00:00:00, pet
2009-vlj-07
00:00:00, sub
2009-vlj-08
00:00:00, ned
2009-vlj-09
00:00:00, pon
2009-vlj-10
00:00:00, uto
Datum i Vrijeme
3.harmonikstrujeufaziodvodaHŽ1iHŽ2[A]
TR HŽ 1 - Ih3 RMS L2 10' A TR HŽ 2 - Ih3 RMS L2 10' A
3rd
currentharmonicfrom
electricrailwaysystem(A)
Date and time
3rd current harmonic in phase L2 of the
electric railway drain at 110 kV level
Power quality measurements

18. Measurements on
110 kV busbars Planning
levels for HVPhases L2,
L3
Phase
L1
THD 1,8 % 0,8 % 3 %
Uh3 0,9 % Uh1 0,3 % Uh1 2 % Uh1
Uh5 0,6 % Uh1 0,5 % Uh1 2 % Uh1
Uh7 0,5 % Uh1 0,2 % Uh1 2 % Uh1
Uh9 0,3 % Uh1 0,0 % Uh1 1 % Uh1
Uh11 0,6 % Uh1 0,3 % Uh1 1,5 % Uh1
Uh13 0,8 % Uh1 0,4 % Uh1 1,5 % Uh1
Uh15 0,4 % Uh1 0,1 % Uh1 0,3 % Uh1
Uh17 0,4 % Uh1 0,2 % Uh1 1,2 % Uh1
Uh19 0,4 % Uh1 0,1 % Uh1 1,1 % Uh1
Uh21 0,5 % Uh1 0,0 % Uh1 0,2 % Uh1
Uh23 0,6 % Uh1 0,3 % Uh1 0,9 % Uh1
Uh25 0,8 % Uh1 0,3 % Uh1 0,8 % Uh1
Comparison between measured values and planning levels for
harmonic voltages according to IEC 61000-3-6
Power quality measurements

19. Modelling of reactive power
compensation for the electric railway
systems and analysis of switching
transients

20. • Improves the system power factor
• Reduces network losses
• Avoids penalty charges from utilities for excessive
consumption of reactive power
• Reduces cost and generates higher revenue for the
customer
• Increases the system capacity and saves cost on new
installations
• Improves voltage regulation in the network
• Increases power availability
Reactive power compensation - benefits

21. Reactive power compensation implies compensating the reactive
power consumed by electrical motors, transformers etc.
Reactive power compensation

22. Reactive power compensation - example
• 28 branches of capacitor banks for compensation of inductive
reactive power consumed by electric locomotives (total QC=2716
kVAr).
• Reactors for compensation of capacitive reactive power of the 25 kV
contact network (4 degrees of regulation, total QL=30 kVAr).
• Connected to 25 kV network via power transformer 2.7 MVA
(27.5/0.69 kV).

23. Reactive power compensation - example
• Single branch (QL=96.8 kVAr) consists of 12 capacitor banks and
a filter reactor.
C – 46 µF, 20.5 kVAr single capacitor
Lf – 2.54 mH, filter reactor
R – 1.342 MΩ – resistance for capacitor discharge

24. Transformator na lokomotivi 25 kV/1060 V Diodni ispravljaci
Istosmjerni motor
Kontaktna mrezžaEVP transformatori 2x7,5 MVA, 110/27,5 kVEkvivalent vanjske 110 kV mrezže
Postrojenje za kompenzaciju 2716 kVArEnergetski transformator 2,7 MVAza priklju
ak kompenzacije
LINEDATA
model in: kontaktna_mreza_rv.pun
kontaktna_mreza
DC21040
+
RL9 ?i
0.027,5.033mH
DC31040
+
RL10 ?i
0.027,5.033mH
DC41040
+
RL11 ?i
0.027,5.033mH
DC51040
+
RL14 ?i
0.027,5.033mH
VM+
?v
m13
FD+
FDline2+
1 2
0.22727272727272726
Tr0_5
VM+
?v
m15
VM+
?v
m18
+ A
?i
m19
p+
p-
CTRL
s1+
s1
s2+
s2
s3+
s3
s4+
s4
DEV4
+
115kVRMSLL /_0
AC3
+
RL21
+ A
?i
m23
Ulaz1Izlaz1
DEV2
+
1 2
0.026037735849056602
Tr0_1
+
RL2 ?i
0.004,28.58uH
+
RL3
4.5,15.9mH
+
R2
11
+
L3
50
+
SW1?vi
-1ms|50ms|0
+
0,14.902mH
RL1
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV1
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV3
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV5
Ulaz1
Ulaz2
Izlaz1
Izlaz2
DEV6
q(t)p(t)
p1
50Hz
?s
scope
scp3
scope
scp4
IC
PQ
PQm2
50Hz
?s
VM+
?v
m1
IC
PQ
3-phase
PQm3
50Hz
?s
Ulaz1Izlaz1
DEV7
Ulaz1Izlaz1
DEV8
Ulaz1Izlaz1
DEV9
Ulaz1Izlaz1
DEV10
Ulaz1Izlaz1
DEV11
Ulaz1Izlaz1
DEV12
Ulaz1Izlaz1
DEV13
Ulaz1Izlaz1
DEV14
Ulaz1Izlaz1
DEV15
Ulaz1Izlaz1
DEV16
Ulaz1Izlaz1
DEV17
Ulaz1Izlaz1
DEV18
Ulaz1Izlaz1
DEV19
Ulaz1Izlaz1
DEV20
Ulaz1Izlaz1
DEV21
Ulaz1Izlaz1
DEV22
Ulaz1Izlaz1
DEV23
IC
PQ
PQm4
50Hz
?s
+
SW2?i
5|10|0
+
SW3?i
5|10|0
+
SW4 ?i
-1|10|0
Ulaz1Izlaz1
DEV24
Ulaz1Izlaz1
DEV25
Ulaz1Izlaz1
DEV26
Ulaz1Izlaz1
DEV27
Ulaz1Izlaz1
DEV28
Ulaz1Izlaz1
DEV29
Ulaz1Izlaz1
DEV30
Ulaz1Izlaz1
DEV31
Ulaz1Izlaz1
DEV32
Ulaz1Izlaz1
DEV33
VM+
?v
m2
+
SW5?vi
64.625ms|65ms|0
BUS2
b
c
GND
Model in EMTP-RV
Q=96.8 kVAr
+
C1
46uF
+
R2
1.342M
+
C2
46uF
+
R3
1.342M
+
C3
46uF
+
R4
1.342M
+
C4
46uF
+
R5
1.342M
+
C5
46uF
+
R6
1.342M
+
C6
46uF
+
R7
1.342M
+
L1
?i
2.54mH
Izlaz1
Ulaz1
+
C7
46uF
+
R1
1.342M
+
C8
46uF
+
R8
1.342M
+
C9
46uF
+
R9
1.342M
+
C10
46uF
+
R10
1.342M
+ C11
46uF
+
R11
1.342M
+
C12
46uF
+
R12
1.342M
Diode
rectifier
bridges
DC motors
Compensation
trasformer 2.7 MVA
Compensation 2.716 MVAr
Single branch of
compensation 96.8 kVAr
Locomotive
transformer 25/1.06 kV
25 kV contact line
system and rails
Traction substation
transformer 2x7.5 MVA,
110/25 kV
Equivalent ot the
110 kV transmission
network

25. Diode locomotive operation – without compensation
Voltage at 25 kV level Urms=27.9 kV
Reactive power calculated at 25 kV level in electric traction substation: Qrms=511.8 kVAr
Active power calculated at 25 kV level in electric traction substation: Prms=1.3 MW

26. Diode locomotive operation – with compensation
Voltage at 25 kV level Urms=28 kV
Reactive power calculated at 25 kV level in electric traction substation: Qrms=29.7 kVAr
Active power calculated at 25 kV level in electric traction substation: Prms=1.4 MW
Five branches of capacitor banks connected.

27. Capacitor banks switching transients
• Energization of three different degrees of compensation (1, 5
and 28) – switching on circuit breaker at 25 kV side of
compensation transformer.
• High-frequency inrush currents were calculated. Energization
at peak voltage was analyzed.
• De-energization of capacitor banks at 25 kV level –
overvoltages and transient recovery voltage (TRV) on circuit
breaker.

28. Switching on capacitor banks
Inrush currents at 0,69 kV side of compensation transformer (switching on 28
degrees of compensation): Imax=660 A; Irms=137.6 A
Inrush currents at 0,69 kV side of compensation transformer (switching on 5
degrees of compensation): Imax=3.21 kA; Irms=666.5 A
Inrush currents at 0,69 kV side of compensation transformer (switching on 1
degree of compensation): Imax=5.66 kA; Irms=4.02 kA

29. Switching off capacitor banks (28 degrees)
Circuit breaker current
TRV on circuit breaker Umax=89.84 kV

30. Switching off capacitor banks (1 degree)
Circuit breaker current
TRV on circuit breaker Umax=82.6 kV

31. Power Quality Analysis in the
Electric Traction System with Three-
phase Induction Motors

32. Power Quality Analysis in the Electric Traction System
with Three-phase Induction Motors
The effects of the traction vehicle operation with three-phase induction motors on
power quality in a 110 kV transmission network are investigated
Electrical scheme of traction vehicle with induction motors

33. Power quality measurements
Electric traction substation connection and train position

34. Locomotive operation mode: acceleration
19th harmonic

35. Locomotive operation mode: constant drive
5th harmonic

36. Locomotive operation mode: regenerative breaking
11th harmonic

37. Measurements at 110 kV level

38. Measurements at 25 kV level

39. Influence of the electric railway system
on pipelines and telecommunication
cables

40. Estimation of return current that flows through rails
• The distribution of traction current in the contact line system

41. Estimation of return current that flows through rails
• The part of return current that flows through rails depends on parameters such:
train distance from TPS, rail-to-earth conductance, number of rails which
conduct the return current, single or double track line, soil resistivity, etc.
• In the middle part between the traction vehicle and TPS, the return current of
about 58.5% flows through rails.

42. Induced Voltages on Underground Pipeline in the Vicinity of
the AC Traction System
Induced voltages were analyzed on buried pipeline in case of short circuit
on the electric traction contact line system.
The contact line system and pipeline were modelled using frequency
dependent transmission line model in EMTP-RV.
The figure shows the part of the corridor with total length of 1.5 km and all
distances required for induced voltage calculation.

43. Induced voltages on the buried pipeline were calculated in case of short
circuit on the electric traction contact line system.
Pipeline is earthed over the 1 Ω resistance at the both ends.
Induced Voltages on Underground Pipeline in the Vicinity of
the AC Traction System
AC current source
Contact line
Pipeline
LINE DATA
FD+
FDline1
FD+
FDline2
FD+
FDline3
FD+
FDline4
FD+
FDline5
+
1
R1
+
1
R2
+
5kA /_0
AC1
+
R3
VM+
?v
m1
VM+
?v
m2
VM+
?v
m3
VM+
?v
m4

44. Cross-section of the pole of the AC 25 kV single-track and current directions
Influence of the electric railway system on
telecommunication cables
Contact
wire
Telecommunication
cable
Catenary
wire
Rails

45. Measurements and Simulations in Trail Operation of Electric
Traction Power Supply After Its Modification
• Measurement of the induced
voltage at the end of the
telecommunication cable
• Measurement of the electric
traction current was carried
out in a traction substation

46. Measurements and Simulations in Trail Operation of Electric
Traction Power Supply After Its Modification
a) Current through the electric traction contact conductor;
b) Voltage induced at the end of the telecommunication cable

47. The telecommunication cable was divided into 75 segments in order to determine
the mutual inductance.
Calculated induced voltage versus the contact line length is shown in Figure.
Calculations: 37 V
Measurements: 35 V
Measurements and Simulations in Trail Operation of Electric
Traction Power Supply After Its Modification

48. 1
User Group 2016
Aix-en-Provence, France
9th - 10th June 2016
MODELLING OF 25 kV ELECTRIC RAILWAY
SYSTEM IN EMTP-RV
Prof. Ivo Uglešić, PhD
Božidar Filipović-Grčić, PhD
Faculty of Electrical Engineering and Computing
University of Zagreb, Croatia