Energy Recovery Workshop Madrid, September, 29, … Recovery Workshop Madrid, September, 29, 2015...
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Energy Recovery Workshop Madrid, September, 29, 2015 Regenerative braking and the different traction systems Ignacio González and Eduardo Pilo Spanish Railways Foundation
Transcript of Energy Recovery Workshop Madrid, September, 29, … Recovery Workshop Madrid, September, 29, 2015...
Energy Recovery Workshop
Madrid, September, 29, 2015
Regenerative braking and the different traction systems
Ignacio González and Eduardo Pilo Spanish Railways Foundation
Index
1. Introduction
2. Traction systems and energy recovery
3. Practical evaluation of the energy recovery in three study cases
4. Conclusions
Introduction (1/2)
• The efficiency of regenerative braking depends on the “reachability” of a consumer (another train, an ESS, the grid, etc.) for the regenerated energy. The closer, the better.
• The characteristics of each system determine this “reachability”: – Topologies –more or less meshed–,
– Directionality of the substations –reversible or not–,
– The type of current –AC or DC–
– etc.
Introduction (2/2)
• This presentation describes the energy flows in the railway infrastructure of 3 european countries (UK, Sweden and Spain) in order to provide an overview of the impact of regenerative braking
• This evaluation has been performed in the WP1 of the FP7 Project Merlin, based on the infomation provided by the partners for year 2011 and using a common approach.
1. Introduction
2. Traction systems and energy recovery
3. Practical evaluation of the energy recovery in three study cases
4. Conclusions
Traction systems (1/3): AC 50Hz System
• Catenary split into independent sectors
• Each sector connected to the grid with a transformer
Public grid(3-phase AC 50Hz)
Catenary
Short isolated sections (30-50 km) lower
probability of feeding other trains when
regenerating
Connected to the grid with
transformers a bidirectional power
flow is always possible
AC grid is always “receptive”
Public grid(3-phase AC 50Hz)
CS CS
G
Railway “Transmission” Grid(1-phase, 16.6Hz, 110-132kV)
Catenary
Power plant
Traction systems (2/3): AC16.7 Hz system
• Fed from dedicated power plants or from the public grid (by means of converter stations)
Catenary is virtually continuous
higher probability of feeding other trains when regenerating
Railway “transmission” grid higher probability
of feeding other trains when regenerating, at
longer distances
May be connected to the grid with
converter stations a bidirectional
power flow is sometimes possible
May be supplied directly by
dedicated power plants no
bidirectional flow is possible
AC grid is always “receptive”
Traction systems (3/3): DC System
• Fed from the power grid (typically distribution grids) by means of electronic converters
Public grid(3-phase AC 50Hz)
CatenaryWhen catenary not segmented higher
probability of feeding other trains when braking. BUT only at shorter distances
Converters are normally unidirectional lower
probability of feeding other trains in off-peak periods
Some bidirectionnal converters
Good!
1. Introduction
2. Traction systems and energy recovery
3. Practical evaluation of the energy recovery in three study cases
4. Conclusions
Practical evaluation of the energy flows: Network Rail (United Kingdom)
400 kV13%
275 kV2%
132 kV40%
66 kV8%
33 kV35%
22 kV0%
11 kV2%
Consummed energy, by input voltage (2011)
650 V1%
750 V43%
1x 25 kV52%
2x25 kV4%
Consummed energy, by catenary voltage (2011)
AC overhead 8,049
3rd rail 650/ 750V DC 4,469
Dual AC, overhead/3rd rail DC 35
1500V DC overhead 39
Total electrified 12,592
Non-electrified 18,471
Total 31,063
Electrification capability (km of electrified track)
Network-wide 2011/12
400 kV; 0,40%
275 kV; 0,06%
132 kV; 1,25%
66 kV; 0,01%
33 kV; 0,00%
22 kV; 0,00%
11 kV; 0,00%
Energy returned to grid, by input voltage (2011)
650 V; 0,00%
750 V; 0,00%
1x 25 kV; 1,60%
2x25 kV; 0,12%
Energy returned to grid, by catenary voltage (2011)
Practical evaluation of the energy flows: Network Rail (United Kingdom)
GWh/año
3,174.9
G
Energy entering
substation
3,074.8 GWh/año
Other Loads
(Stations, workshops)
449 GWh/año
Energy regenerated (Returned to the public grid)
52.8 GWh/año
Used by other trains 165 GWh/año
Pantograph 2,711.5 GWh/año
Braking energy 229 GWh/año
Rheostatic energy 8 GWh/año
Regenerated energy 221 GWh/año
Regenerated 54.9 GWh/año
Infrastructure
Auxiliary
80 GWh/año
Public grid (Transmission and Distribution Grids)
Practical evaluation of the energy flows: Adif (Spain)
Single
track non
electrified
Single
track
electrified
Double
track non
electrified
Double
track
electrified
Total
Conventional network 5,274.5 3,421.1 115.8 3,084.9 11,869.3
High-speed network 0.0 140.6 0.0 2,084.7 2,225.4
Total 5,247.5 3,561.7 115.8 5,169.7 14,094.7
3000 V64%
1X25 kV12%
2X25 kV24%
Consummed energy, by catenary voltage (2011)
11-15 kV0%
20-27.5 kV0%
30-36kV0% 44-55 kV
0%66 kV
0%132-145 kV
4%
220 kV36%
380-400 kV60%
Energy returned to grid, by input voltage (2011)
3000 V0%
1X25 kV18%
2X25 kV82%
Energy returned to grid, by catenary voltage (2011)
Practical evaluation of the energy flows: Adif (Spain)
GWh/año
2,456.6
G
Energy entering
substation
2,363.2 GWh/año
Other Loads
(Stations, workshops)
300 GWh/año
Energy regenerated (Returned to the public grid)
62.6 GWh/año
Used by other trains 163 GWh/año
Pantograph 1,968.8 GWh/año
Braking energy 264 GWh/año
Rheostatic energy 36 GWh/año
Regenerated energy 228 GWh/año
Regenerated 64.3 GWh/año
Infrastructure
Auxiliary
235 GWh/año
Public grid (Transmission and Distribution Grids)
Spain Electric Generation Mix (2011)
21,2 % Nuclear
18,7% Solar
18,6% Natural Gas
16% Coal
15,3% Wind
10,2% Hydroelectric
Practical evaluation of the energy flows: Trafikverket (Sweden)
130 kV7%
50 kV7%
22 kV9%
6,3 kV77%
Consummed energy, by input voltage of converter (2011)
Connected to grids in the range 20kV-220kV witha step down transformer
Public grid(3-phase AC 50Hz)
CS CSRailway “Transmission” Grid(1-phase, 16.6Hz, 110-132kV)
Catenary
Energy returned to the grid is
negligible.
Practical evaluation of the energy flows: Trafikverket (Sweden)
GWh/year
2,268.4
G
Energy entering
substation
2,159.2 GWh/year
Other Loads
(Stations, workshops)
35 GWh/year
Energy regenerated (Returned to the public grid)
0 GWh/year
Used by other trains 180 GWh/year
Pantograph 1,968.8 GWh/year
Braking energy 276 GWh/year
Rheostatic energy 95 GWh/year
Regenerated energy 180 GWh/year
Regenerated 0 GWh/year
Infrastructure
Auxiliary
113 GWh/year
Public grid (Transmission and Distribution Grids)
1. Introduction
2. Traction systems and energy recovery
3. Practical evaluation of the energy recovery in three study cases
4. Conclusions
Conclusions
• Summary of the key quantities in the consumption maps:
• Energy regeneration can still be improved by further adoption of existing energy efficient technologies (regenerative trains, ESS, reversible substations, etc.)
UK Spain Sweden
Energy measured at PCC 100,0% 100,0% 100,0%
Energy consumed at pantograph 88,0% 83,3% 91,2%
Energy returned to catenary 7,2% 9,6% 8,3%
Energy returned to grid 1,7% 2,6% 0,0%
Energy cons. for ancillary systems 2,6% 9,9% 5,0%
Energy to feed other loads 14,6% 12,7% 1,6%
Thanks for your attention
Ignacio González Franco
Eduardo Pilo de la Fuente
