IEEE Electrification - September 2019 - 70

Energy Consumption

Energy Consumption Distribution
of the Whole Life Cycle of the Train
Operating
Production and Manufacturing

Maintenance

Scrapping

Research and Design
Life Cycle
Figure 3. A distribution of the life-cycle cost of high-speed trains.

TABLE 4. The energy consumption composition of train operations.

(Source: B. Sun et al., p. 70.)

Energy Consumption in High-Speed
Train Operation
Traction energy
consumption

Energy Consumption Category

Proportion
(%)

Kinetic energy loss

Aerodynamic resistance energy consumption
Energy consumption of traction equipment

Auxiliary power
consumption

Auxiliary equipment load energy consumption

Temperature-adjustable energy consumption
Energy loss

Transmission energy
consumption

Friction and wear/transmission efficiency

Other

Line loss, transformer substation conversion
loss, and so on

22%
20%

Passenger Service
Function

69%

Running Resistance

63%

Inertia and Slope
Resistance

17%
20

40
(%)

High-Speed Rail (With Regenerative Breaking)
High-Speed Rail (Without Regenerative Breaking)
Figure 4. The energy demand of a high-speed railway.

I E E E E l e c t r i f i cati o n M agaz ine / SEPTEMBER 2019

consumption accounting for the
largest proportion. Figure 3 shows
the complete life cycle of highspeed trains.
Operating high-speed trains
consumes electrical energy in
the forms of tractive energy consumption, auxiliary energy consumption, transmission energy
consumption, and other losses
(e.g., line loss, and so on), as
shown in Table 4. According to the
Association of Train Operating
Companies and the I n t e r c i t y
Express Programme (an initiative
of the Department for Transport),
a new Rail Safety and Standards
Board tractive energy consumption report concluded that the
operational energy demand of
high-speed trains includes auxiliary energy consumption for providing passengers with service
functions as well as traction energy
consumption for overcoming inertia, slope resistance, and trainrunning resistance, as depicted in
Figure 4. Auxiliary energy consumption includes the energy consumed
by passenger service functions and
equipment, e.g., lighting, ventilation, and heating.
For high-speed trains, aerodynamic drag dominates operational
resistance, and energy consumption is proportional to the square of
the speed. When the speed reaches
200 km/h and 350 km/h, the energy
consumed from overcoming the air
resistance accounts for 70% and
85% of the total traction energy
consumption, respectively. Optimizing the train body and reducing
the overall weight of the train can
improve the train's aerodynamic
performance, which is crucial for
reducing the running energy consumption of trains.
The high-speed train electric
energy circulation path is as follows: traction power supply overhead lines $ high-speed train
$ wheel rail $ traction networks. Energy-efficient traction
components, i.e., power electronic transformers and permanent

IEEE Electrification - September 2019

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