Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
25kV Traction Power System Modelling - TRAIN AC Validation Report
May 2008
Mott MacDonald St Anne House 20-26 Wellesley Road Croydon Surrey CR9 2UL UK Tel : 44 (0)20 8774 2000 Fax : 44 (0)20 8681 5706
May 2008 P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Notes to this version
For Issue to Network Rail
iii 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Reference & Bibliography
1. Validation of the TRAIN Program DC Validation, rev A, dated 21/2/06.
2. Network Rail’s Crossrail Simulation Report rev A, Ref TBA
List of Abbreviations
Abbreviation Description AC Alternating Current BR British Rail DC, dc Direct Current EMU Electric Multiple Unit IECC Integrated Electronic Control Centres LU London Underground MPTSC Mid-point Track Sectioning Cabin NR Network Rail OCS Overhead Contact System OHLE Overhead Line Equipment OOC Old Oak Common RMS Root Mean Square TE Tractive Effort TSC Track Sectioning Cabin TSL Track Sectioning Location TRAIN Mott MacDonald’s train simulation program
iv 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Summary
This report compares the outputs of Mott MacDonald’s TRAIN simulation package with that of Network Rail’s Vision OSLO simulator. This comparison is preceded by a basic system examination of the AC operational aspect of the TRAIN simulator with a simplified model in Matlab.
In this exercise, TRAIN comparisons with Matlab have demonstrated accuracies of less than 0.5%, while Vision OSLO comparisons (in areas where like-for-like inputs were noted) showed accuracies of less than 10%.
v 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Contents
Reference & Bibliography iv
List of Abbreviations iv
Summary v
1 Introduction 1
2 Basic Circuit Comparisons 1 2.1.1 Summary of Simulation Results 3
3 Vision OSLO Comparisons 9 3.1 Description of TRAIN Model 9 3.1.1 Train Types and Services 9 3.1.2 Resistance to motion 9 3.1.3 Stations and Infrastructure 10 3.1.4 Electrical Model 10 3.2 Summary of Simulation Results 11
4 Findings and Conclusions 16 4.1 Basic AC Models – Comparisons with Matlab 16 4.2 Substation Loading – Comparisons with OSLO 16 4.3 Minimum Line Voltage Profile – Comparisons with OSLO 17 4.4 General Comparisons 17
Appendix A: Crossrail Major Feeding Diagram 18
Appendix B: Input Data 19
Appendix C: Graphical Outputs from TRAIN 20
Appendix D: Matlab Calculations for Single train model 21
Appendix E: Outputs from Crossrail Model in TRAIN 23
vi 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
1 Introduction
Mott MacDonald’s TRAIN program is a PC based modelling package that allows the assessment of energy and power consumptions in metro, heavy rail and tram systems. The program is multi-nodal, enabling the behaviour of a number of rolling stock and electrification system parameters to be modelled, in the assessments of system performance, or the suitability of system design. The program requires route information (gradients, stations and signals), electrification system characteristics, train characteristics, and the timetable (or a specified service headway) to which the service is run. The simulation calculates the following variables: • Busbar voltage at feeder stations; • Maximum and minimum voltage and current profiles along the route; • Peak current supplied by each distribution transformer at the feeder station; • RMS currents supplied by each feeder station over various time periods; • RMS power supplied by each feeder station over various time periods; • Current through each OCS feeder; It should be noted that the above list is by no means comprehensive, but rather a good indication of some of the key variables that is available in the TRAIN program.
The mechanical and dc electrification part of this program has been validated to +/-10% by London Underground Limited with the use of measured data; the full details of this exercise are documented in Ref 1.
The dc validation of the TRAIN program has now been endorsed by Network Rail (NR), the public body with responsibility (as infrastructure controller) for the majority of the railway (over-ground) infrastructure in Britain. This endorsement was provided (to MM) after a detailed assessment of TRAIN simulation results on the Southern Region with the equivalent results from Vision-OSLO (the principal tool employed for power simulation work on NR infrastructure).
To promote TRAIN’s use as a valid tool for modelling AC traction systems and provide evidence to third parties such as Network Rail of its capability for modelling with accuracy, an exercise has been carried out with the AC part of the TRAIN program to demonstrate that the results from TRAIN, correlate acceptably with:
1. ‘basic AC circuit principles’ and 2. Network Rails Vision-OSLO package.
2 Basic Circuit Comparisons
Two basic AC circuits (see figure 1 and 2) have each been modelled in Matlab and in TRAIN for comparison. The Matlab™ package is a commercial tool produced by Mathworks for numerical analysis and design. The underlying algorithms within the package allow easy matrix manipulation and implementation of algorithms. For the two circuits in this exercise, the formulation of a numerical solution in Matlab has been carried out as follows: 1 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
a. All trains have been configured with a stationary constant power load of 7.2MW and a power factor of 0.95; an iterative process that assumes a starting voltage of 25kV at the train and a no-load voltage of 26.5kV at the Feeder Station was modelled.
b. The above values are then employed in the first iteration that calculates train current(s) and the equivalent train impedance(s).
c. These values are then used as the base for further calculations to determine the busbar voltage and its angle, with respect to the source, as well as the train voltage and angle (with respect, to the source).
d. Once the above steps are complete, a feedback loop is triggered for a second iteration, using the outputs from the first iteration as input data.
The iterative process (in the Matlab model) is repeated, until the voltage at the pantograph of the train converges to 0.1% of the no-load voltage. For simplicity; the calculations in iteration 1 of the single train model has been replicated in Appendix D
Figure 1: Single train model in Matlab
Notes to Matlab model illustrations in Figures 1& 2:
i) The abbreviations provided in figures 1&2 are fully defined in Appendix B
ii) All resistance values are in ohm, and inductance values are in Henry
iii) The load impedance represents the equivalent train impedance when converged to a solution
2 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Figure 2: Two trains modelled in Matlab
2.1.1 Summary of Simulation Results
The comparison of results between TRAIN and Matlab have been carried out with consideration to the following variables:
• the source current, and associated angle
• the busbar voltage and associated angle (with respect to the source)
• the train voltage(s) and associated angle(s) (with respect to the source)
• the train current(s) and associated angle(s) (with respect to the source)
From the TRAIN program, the numerical results for the above variables are captured (in Appendix C) as screen-shots. The outputs from this exercise are also available as plots, on request.
It should be noted that, although the calculation of the above variables occur at each time-step in the TRAIN program, the Matlab program represents only one-time step (of the TRAIN program) therefore, the use of a constant load (in TRAIN), allows the nearest comparison between the two packages.
The exact values (for the above variables) in Matlab and in TRAIN are as followed:
• Busbar Matlab Model - with one stationary Matlab Model - with two stationary Voltage train trains
Voltage = 25.9552kV Voltage = 25.0903kV
3 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Voltage = 25.955kV Voltage = 25.089kV
% difference = 0.0 % difference = 0.01
• Busbar Matlab Model - with one stationary Matlab Model - with two stationary Voltage Angle train trains
Angle = -2.61280 Angle = -5.47640
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Angle = -2.60000 Angle = -5.50
% difference = 0.49 % difference = 0.43
• Train 1 Matlab Model - with one stationary Matlab Model - with two stationary Voltage train trains
Voltage = 25.4037kV Voltage = 23.8087kV
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Voltage = 25.404kV Voltage = 23.806kV
% difference = 0.0 % difference = 0.01
• Train 1 Matlab Model - with one stationary Matlab Model - with two stationary Voltage Angle train train
Angle = -4.7220 Angle = -10.13350
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Angle = -4.70 Angle = -10.10
% difference = 0.47 % difference = 0.33
• Train 2 Matlab Model - with one stationary Matlab Model - with two stationary Voltage train trains
Voltage = N/A Voltage = 23.2017kV
4 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Voltage = N/A Voltage = 23.198kV
% difference = N/A % difference = 0.02
• Train 2 Matlab Model - with one stationary Matlab Model - with two stationary Voltage Angle train train
Angle = N/A Angle = -12.64960
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Angle = N/A Angle = -12.70
% difference = N/A % difference = -0.40
• Train 1 Matlab Model - with one stationary Matlab Model - with two stationary Current train trains
Current = 298.4107A Current = 318.2081A
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Current = 298.3A Current = 318.4A
% difference = 0.04 % difference = -0.06
• Train 1 Matlab Model - with one stationary Matlab Model - with two stationary Current Angle train trains
Angle = -22.91690 Angle = -28.32840
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Angle = -22.90 Angle = -28.30
% difference = 0.07 % difference = 0.10
• Train 2 Matlab Model - with one stationary Matlab Model - with two stationary Current train trains
5 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Current = N/A Current = 326.5038A
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Current = N/A Current = 326.7A
% difference = N/A % difference = -0.06
• Train 2 Matlab Model - with one stationary Matlab Model - with two stationary Current Angle train trains
Angle = N/A Angle = -30.84450
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Angle = N/A Angle = -30.90
% difference = N/A % difference = -0.18
• Source Matlab Model - with one stationary Matlab Model - with two stationary Current train trains
Current = 644.5566A Current = 644.5566A
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Current = 644.9A Current = 644.9A
% difference = -0.05 % difference = -0.05
• Source Matlab Model - with one stationary Matlab Model - with two stationary Current Angle train trains
Angle = -29.60260 Angle = -29.60260
TRAIN Model - with one stationary TRAIN Model - with two stationary train trains
Angle = -29.60 Angle = -29.60
% difference = 0.01 % difference = 0.01
6 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Stationary Train Comparisons [Matlab & TRAIN]
700
600
500
400
300
200 Matlab Model TRAIN Model 100
0
-100 Busbar Voltage (kV) Voltage Busbar (degrees) Angle (kV) Voltage Train Angle Voltage Train Train Current (A) Angle Current Train Source Current (A) (degrees) Angle Busbar Voltage Busbar Source Current (degrees) (degrees)
Stationary Train Comparisons [Matlab & TRAIN] % Difference
0.10
0.00
-0.10 percentage (%)
-0.20
-0.30 % Difference
-0.40
-0.50 Busbar Voltage (kV) Voltage Busbar Angle (degrees) (kV) Voltage Train Angle Voltage Train (A) Current Train Angle Current Train (A) Current Source Angle (degrees) Busbar Voltage Busbar Source Current Source (degrees) (degrees)
7 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Two Stationary Train Comparison [Matlab & TRAIN]
700
600
500
400
300
200 Matlab Model TRAIN Model 100
0
-100 Busbar Voltage (kV) Angle (degrees) (kV) 1 Voltage Train Angle (degrees) (kV) 2 Voltage Train Angle (degrees) (A) Current 1 Train Angle (degrees) (A) Current 2 Train Angle (degrees) Source Current(A) Angle (degrees) Busbar Voltage 1 Voltage Train 2 Voltage Train Source Current Train 1 Current Train 2 Current Train
Two Stationary Train Comparison [Matlab & TRAIN] % Difference
0.50
0.40
0.30
0.20 Percentage (%)
0.10
0.00
-0.10 % Difference
-0.20
-0.30
-0.40 Busbar Voltage (kV) Voltage Busbar (degrees) Angle (kV) 1 Voltage Train (degrees) Angle (kV) 2 Voltage Train (degrees) Angle (A) 1 Current Train (degrees) Angle (A) 2 Current Train (degrees) Angle (A) Current Source (degrees) Angle Busbar Voltage Busbar 1 Voltage Train 2 Voltage Train Source Current Source Train 1 Current Train 2 Current Train
8 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
3 Vision OSLO Comparisons The power simulation exercises for Crossrail have presented an opportunity for comparisons of the outputs of TRAIN with Vision OSLO. The Vision OSLO simulator has been the tool of choice (for NR) in power simulation modelling. This package can be traced as far back as the 1970s where earlier versions of this model were employed on Main frame computers for the design of British Rails' Automatic Route Setting algorithms which later became a standard part of BR’s Integrated Electronic Control Centres (IECC).
The current version of this package was conceived in 1987 and has been employed in the designs of almost every upgrade of the 25kV infrastructure in the UK ever since.
The representation of the Crossrail Infrastructure (in TRAIN) has been implemented (as far as practicable) to mirror the model in OSLO; however, as the original TRAIN model was developed separately from the OSLO model, with the intention of designing the Traction Power system, using the most up-to-date information; the following differences have emerged in the two models.
1. With no signalling scheme in place for the Crossrail infrastructure a moving block system has been used in the TRAIN model, however for the Vision-OSLO model, a fixed block system has been implemented (based on NR assumptions).
2. The Crossrail alignment for the central section has been implemented in the OSLO model using alignment J; while the TRAIN model has been implemented with the use of alignment L. A detailed summary of the inputs to the TRAIN model are provided below.
3.1 Description of TRAIN Model
3.1.1 Train Types and Services
The timetable for the Crossrail service has consisted of approximately 18 individual train types on differing journeys across the network. These journeys are distributed (between Maidenhead and Shenfield) over a five and half hour window that commences at 05:30 hours. The lists of train types that have been modelled have included: the class 92, 313, 315, 321, 221, 253 and 360.
To model the 5MW Crossrail trains, envisaged at the time of the OSLO modelling, for the central section of the infrastructure, a class 360 train was up-rated from 4MW to 5MW to mirror the model in Vision OSLO, where the train was configured for a 10-car arrangement.
3.1.2 Resistance to motion
The resistance to motion is given per train through the Davies equation. The coefficients to the Davies equation for all the train types modelled have been, taken from the OSLO library.
9 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
3.1.3 Stations and Infrastructure
In total, the system model consisted of forty stations located in numerous locations along the infrastructure from Maidenhead in the west to Shenfield in the east and Abbeywood in the south-east. The gradient profiles in the central section have been sourced from the Rail Alignment Report for the Crossrail scheme (1D300-G0T00-05005/A2).
On the Great Western and Great Eastern Main Lines, the gradient information (on this section of the network), in the ‘British Rail Gradient Profile’ handbook has been used in the model.
For speed limits, the Rail Alignment Report 1D300-G0T00-05005/A2 has once again provided the data used in the central section area.
On the Great Western and Great Eastern Mainlines the speed limits information has been taken from the Sectional Appendixes in NR3001802-03.
3.1.4 Electrical Model
The electrification system simulated consists of thirteen electrical sections fed from eight individual Feeder Stations. The Major Feeding diagram is provided in Appendix A. The simulation model has been configured to account for six MPTSCs and eight TSCs. The location of each system and transformer ratings (for the Feeder Stations) are presented in the tables below, a graphical illustration of the scheme is provided in Appendix A.
Table 2.2.1 : Feeder stations and transformer ratings
Present transformer rating Substations (MVA) Bow 2 * 26.5 Custom House 2 * 80 Crowlands 2 * 26.5 Hayes 1 * 10 Iver 2 * 26.5 Old Oak Common 1 * 26.5 Shenfield 1 * 26.5
Westbourne Park 1 * 80 with another one on standby
Table 2.2.2 : MPTSC and TSC’s
MPTSCs TSCs Hanwell Maidenhead Hayes Burnham Farringdon Hayes Pudding Mill Ealing
10 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Manor Park Stepney Green Gidea Park Abbey Wood - Ilford - Brentwood
At each of the Feeder stations, the simulation has been configured for a no-load voltage of 26.5kV.
The following source impedance values have been used:
• 0.154 + j4.417 – at Iver; Westbourne Park; Old Oak Common; Bow; Crowlands and Shenfield
• 0.25 + j6.90 – at Hayes
• 0.077 + j4.42 – at Custom House
The source impedance values above have been calculated to ensure that a 6kA fault level is not exceeded.
The section impedance values on the network were obtained from the NR OSLO library. These values were provided with the booster transformer impedance value already included.
For this reason the TRAIN simulation model has been configured as a rail return circuit, although this is representative of a booster transformer system.
3.2 Summary of Simulation Results
A full schedule of results from the TRAIN simulation program is available as an accompaniment to this report (on request). Extracts of these results are presented in Appendix E.
The results from this exercise which are presented as graphical plots from TRAIN include:
• The 30-minute Rolling RMS Power at every Feeder Station.
• The 1-minutes Rolling RMS Power at every Feeder Station.
• The Instantaneous Power drawn at every Feeder Station
• The 30-minute Rolling RMS Current at every Feeder Station.
• The 1-minutes Rolling RMS Current at every Feeder Station.
• The Instantaneous Current drawn at every Feeder Station
• The Minimum Line Voltage against Chainage Profiles across the infrastructure
Of the numerous outputs listed, the most significant of these for comparisons with the outputs from the Vision OSLO simulator, have been the Feeder Station Loadings, which are best represented by the ‘30-minute Rolling RMS Power’ for the transformers at the Feeder Stations, and the lowest voltage at the pantograph, which is shown in the ‘minimum line voltage against chainage’ plots.
11 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
For the Feeder Station Loadings the comparable value (at each site) from the two simulators are listed in the table below.
Feeder Station Loading (MVA) Name OSLO TRAIN % difference Iver F1 6.39 7.5 17.37 Iver F2 9.1 9.76 7.25 Hayes FS 4.68 3.58 -23.50 Old Oak Common FS 11.82 15.78 33.50 Westbourne Park FS 21.07 16.81 -20.22 Custom house F1 19.47 18.94 -2.72 Custom house F2 9.46 9.51 0.53 Bow Junction F1 11.55 12.23 5.89 Bow Junction F2 14.36 12.01 -16.36 Crowlands F1 18.65 18.67 0.11 Crowlands F2 9.18 9.8 6.75 Shenfield F1 15.91 15.05 -5.41
Table 1: Feeder Stations Loadings
Feeder Station Loadings (MVA)
25
20
15
10 OSLO TRAIN
5
0 Iver F1 Iver F2 FS Hayes Old Oak Common FS Park Westbourne house F1 Custom house F2 Custom F1 Junction Bow F2 Junction Bow F1 Crowlands F2 Crowlands F1 Shenfield FS
12 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Figure 3: Feeder Station Loading with OSLO & TRAIN (1)
OSLO vs TRAIN
25
20
15
OSLO TRAIN
10 Apparent Power Loading (MVA) Loading Power Apparent 5
0
1 F1 FS FS FS F F1 F2 r r F2 n n o ld F1 Ive Ive yes on i ie a ouse lands F2 H h enf omm ne Park m m house F2 Junct Junctio C r o Sh sto Crowlands F1 Crow bou u ow C Cust B Bow Old Oak West
Figure 4: Feeder Station Loading with OSLO & TRAIN (2)
The minimum line voltage encountered by a train on the infrastructure is captured at discrete locations (on the network) from the west (of the infrastructure) to the east (see Appendix A). The profile and comparisons for the line voltage are presented in the tables and figures below.
Minimum instantaneous Voltage TRAIN OSLO % Difference (kV) Maidenhead TSL 25.6 24.9 2.73 Burnham TSL 25.4 25.1 1.18 Iver F1 25.05 25.5 -1.80 Iver F2 25.05 24.7 1.40 Hayes TSL 24 24.1 -0.42 Hayes FS 24.7 25.3 -2.43 Central Terminal 1 25.7 25.1 2.33 Central Terminal 2 25.7 25 2.72 Ealing TSL 24.5 24.7 -0.82 Heathrow Airport 25.8 25 3.10 Old Oak Common 24.7 24.9 -0.81 Heathrow Airport (T5 up) 25.2 25.1 0.40 Heathrow Airport (T5 dn) 25.9 25 3.47
13 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Minimum instantaneous Voltage TRAIN OSLO % Difference (kV) Hanwell MPTSC1 24.2 24 0.83 Hanwell MPTSC2 24.2 24.6 -1.65 Westbourne Park MPTSC1 24.4 24.8 -1.64 Westbourne Park Fyover 24.4 24.9 -2.05 Westbourne Park MPTSC2 24.4 24.8 -1.64 Paddington Station Platform 1 24.7 24.8 -0.40 Paddington Station Platform 3 24.7 24.8 -0.40 Paddington Station Platform 5 24.7 24.8 -0.40 Paddington Station Platform 7 24.7 24.8 -0.40 Paddington Station Platform 9 24.7 24.8 -0.40 Paddington Station Platform 10 24.7 24.8 -0.40 Paddington Station Platform 11 24.7 24.8 -0.40 Westbourne Park FS 24.4 23.2 4.92 Farringdon MPTSC 1 23.6 22.8 3.39 Farringdon MPTSC 2 22 22.2 -0.91 Pudding Mill Lane MPTSC 22.4 22.3 0.45 Custom House F1 24.7 22.9 7.29 Custom House F2 24.7 25.4 -2.83 Abbeywood TSL 23.9 24.9 -4.18 Liverpool Street Station Platform 23.6 22.2 2 5.93 Crowlands F1 24.2 23 4.96 Crowlands F2 24.2 24.3 -0.41 Gidea Park MPTSC1 22.9 24.1 -5.24 Gidea Park MPTSC2 22.9 23 -0.44 Brentwood TSL 23.9 23.2 2.93 Shenfield F1 23.6 23.6 0.00
14 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Minimum Line Voltage Profiles
30
25
20
TRAIN 15 OSLO Voltage (kV) 10
5
0 Maidenhead TSL Maidenhead TSL Burnham Iver F1 Iver F2 Hayes TSL Hayes FS Central Terminal 1 Central Terminal 2 Ealing TSL Airport Heathrow Old Oak Common up) (T5 Airport Heathrow dn) (T5 Airport Heathrow MPTSC1 Hanwell MPTSC2 Hanwell MPTSC1 Park Westbourne Fyover Park Westbourne MPTSC2 Park Westbourne 1 Platform Station Paddington 3 Platform Station Paddington 5 Platform Station Paddington 7 Platform Station Paddington 9 Platform Station Paddington 10 Platform Station Paddington 11 Platform Station Paddington FS Park Westbourne 1 MPTSC Farringdon 2 MPTSC Farringdon MPTSC Lane Mill Pudding F1 House Custom F2 House Custom TSL Abbeywood 2 Platform Station Street Liverpool F1 Crowlands F2 Crowlands MPTSC1 Park Gidea MPTSC2 Park Gidea Brentwood TSL Shenfield F1
Figure 5: Minimum Line Voltage
15 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
4 Findings and Conclusions
4.1 Basic AC Models – Comparisons with Matlab
The results, in section 2.1.1 have demonstrated close correlations between the Matlab model and the TRAIN model, where comparable results were seen to mirror one another with little to no deviations.
With a convergence tolerance of 0.1% in the Matlab model, the TRAIN program has been shown to obey the basic principles for AC circuit calculations to an accuracy of within 0.5% of the Matlab results.
4.2 Substation Loading – Comparisons with OSLO
In general the trends in the loadings at the Feeder Station follow a similar pattern in both the TRAIN and OSLO results (see figure 4).
The areas where the results vary the most is at Hayes FS, Old Oak Common FS and Westbourne Park FS. At these sites:
The variances in the results are attributed to the differences in input data, for the two models. This is especially the case for Old Oak Common (OOC) and Westbourne Park (WBP), where the impact of having two separate signalling systems and two different gradient profiles, is most evident; from a summation of the loads.
This summation (of 11.8MVA for OOC and 21.07MVA for WBP) results in a value of 32.8MVA (for Vision OSLO) and the equivalent results of 15.78MVA for OOC and 16.81MVA for WBP produces a result of 32.6MVA for TRAIN.
This simple comparison shows that although the two Feeder Stations experience a different share of the load (in the two models), the loads are still the same when combined; which suggests that the positioning of the trains are different due to the difference in the signalling systems and also the difference in gradient.
This difference, in the positioning of the trains for the two models is also seen as a factor for the disparity (between TRAIN and OSLO) at Hayes Feeder Station.
The areas where the results vary the least is at Crowlands F1 & F2 and Shenfield FS.
The close correlations between the results at these sites are once again attributed to the input data. As most of the infrastructure on the Great Eastern is existing, and will remain unaltered for the Crossrail project (especially gradients); the MM model in TRAIN would be exactly the same as the OSLO model. This assertion is supported by the close correlations, in results at Crowlands FS (F1 and F2) and Shenfield FS.
16 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
4.3 Minimum Line Voltage Profile – Comparisons with OSLO
The trend for the Minimum Line Voltage results, in both TRAIN and OSLO show good correlations to one another with variations of less than 10% in results, even when the signalling systems and track alignments are not identical.
4.4 General Comparisons
The comparisons of TRAIN with the equivalent models in Matlab and in Vision OSLO have produced good correlations that endorse the use of TRAIN as a valid and accurate tool for AC Simulation modelling.
Although the comparisons with the OSLO model, produced disparities in certain locations; in the areas where the input data for the infrastructure were at the closest; the correlations were most evident.
All of this is reinforced by the Matlab models, which use the same parameters as TRAIN and produce comparable results to within 0.5%.
It is concluded from this exercise that train is as acceptable as Vision OSLO for AC Power Simulation modelling.
17 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Appendix A: Crossrail Major Feeding Diagram
18 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Appendix B: Input Data
Input parameters - variable d1 = 10000; %10km - source to train 1 d2 = 10000; %10km - train 1 to train 2 Ptrn1 = 7.2e6; %Power of train 1 in MW pf1 = 0.95; %Power factor of train 1 Ptrn2 = 7.2e6; %Power of train2 in MW pf2 = 0.95; %Power factor of train 2
Input parameters for 25kV infrastructure - constant Vs = 26500 + 1i*0; %Source voltage in Volts (Reference for all quantities) Vnom = 25000; %Nominal train pantograph voltage in Volts f = 50; %frequency of calculation wo = 2*pi*f; %Angular frequency (rads/sec) Rs = 0.221; %Source resistance in Ohm Ls = 0.014; %Source inductance in Henry Xs = wo*Ls; %Source reactance in Ohm Rc = 0.05e-3; %Loop resistance of OHLE in Ohm Lc = 0.923e-6; %Loop inductance of OHLE in Henry Xc = wo*Lc; %Loop reactance of OHLE in Ohm Rbt=0.02e-3 %Resistance/m of booster transformer based on booster transformer spacing of 3km Lbt=0.223e-6 %Inductance/m of booster transformer (Note: Zbt=0.06 +j0.21 ohm assumed) Xbt=0.07e-3 %Reactance/m of booster transformer (Note: Zbt=0.06 +j0.21 ohm assumed)
19 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Appendix C: Graphical Outputs from TRAIN
Stationary train in TRAIN:
Two Stationary trains in TRAIN:
20 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Appendix D: Matlab Calculations for Single train model
[Iteration 1]
Step 1: Calculate equivalent train impedance and the source current
• Vtrn = 25kV • Ptrn = 7.2MW • p.f = 0.95 VI Cos θ = P
P e62.7 I == = 158.303 A VCosθ e 95.0*325
Vtrn e325 ∠φ Ztrn == 19.18465.82 Ω°∠= (an initial estimate) Itrn 158.303 −∠ ϑ
Ztrn j 743.25344.78 Ω+= (an initial estimate)
ZtrnZcZsZt =++= += j eje ++−+−+ j )743.25344.78()36.337.0()3988.4221.0( Ω
+= j 1454.305657.78 Ω 99.20151.84 Ω°∠=
Vs 05.26 °∠= kV
Vs 05.25 °∠ Is == 2107.304 °−∠= A Zt 99.20151.84 °∠
Step 2: Calculate the busbar voltage and the train voltage
−= IsZsVsVbus j +°−∠−+= j )3988.4221.0(*2107.304)026500( j −+= ∠ )12.66124.1339()026500(
−−= j )488.1224107.54226500( = − j 488.1224893.25957 7.2987.25 °−∠= kV
21 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
−= IsZcVbusVtrn Vbus e 1793667.32107.304 °∠−×°−∠−= Vbus 58115.1 °∠−=
= − j −− j 946.0591.0488.1224893.25957 = − j 434.1225302.25957 = 703.221.25986 °−∠ kV
[Iteration 2]
Step 3: Calculate equivalent train impedance and the source current -1
P e62.7 I == = 653.291 A VCosθ e 95.0*398621.25
φ 1 CosepfCose 195.18)95.0(1 °=−=−=
Vtrn e −∠ 703.2398621.25 Ztrn == 19.18465.82 Ω°∠= Itrn 703.2653.291 −−∠ φ
Ztrn 195.180998.89 Ω°−∠=
Ztrn −= j 8216.276447.84 Ω
++= ZtrnZcZsZt …………………………………………………
Vs 05.26 °∠= kV
Vs Is == ...... Zt
22 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
Appendix E: Outputs from Crossrail Model in TRAIN
23 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
24 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
25 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
26 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL
Network Rail Mott MacDonald 25kV Traction Power System Modelling - TRAIN AC Validation Report
27 211197 /02/A May 2008/ P:\Croydon\MMH\Railways\211197 - Taiwan TRAIN sale\Validation\ac validation\AC Validation Report.doc/KL