IEEE Electrification - September 2019 - 67

energy consumption curve, the traction power curve, and the
empirical regression formula of trains. On this basis, a variety
of intelligent optimization algorithms-e.g., discrete and
continuous control algorithms, genetic algorithms (GAs), and
particle swarm optimization algorithms (PSOs)-were introduced to calculate a series of operating points so that the
optimal running curve of the train is obtained when energy
consumption is reduced. In addition, the recycling of trainbraking energy is an important approach for ensuring energy
optimization; this includes resistance energy consumption,
energy storage, inverter feedback, and other direct uses of
traction loads.
This article summarizes the transportation management mode and optimal control strategy of high-speed
trains in China, Japan, Europe, and other countries and
sheds light on their future development trends.

Traffic Management of High-Speed Trains

current system of an electrified railway, composition of the
traction power supply system, and traction drive system.

Current System for Electrified Railways
The current system of an electrified railway specifically
refers to the type of current used by electrified railways in
the traction network. Electric traction is divided into dc
systems; low-frequency, single-phase ac systems; powerfrequency, single-phase ac systems; and a three-phase ac
systems, according to the type of traction network supply
current. The three-phase ac system has been phased out
due to its complex structure and other technical reasons.
The system adopted by countries today gradually
tends to be unified, and its voltage is constantly increasing. For example, Italy, Poland, and other countries have
implemented 3,000-V dc systems; China, France, Japan,
and others use 25-kV single-phase, power-frequency ac
systems; and Germany, Sweden, and others use 16.67-Hz
single-phase, low-frequency ac systems. With a rise in the
total amount of transportation and continuous improvement of traffic density and speed, high-speed railways are
steadily moving in the direction of increased speed, heavy
load, and high density. Some countries have begun to

Traction Power Supply System
for Electrified Railways
An electrified railway is a form of
rail transportation that uses electric
energy as traction. It has the advantages of large traction power, a high
comprehensive utilization of energy,
low environmental pollution, and
easy-to-realize automatic control
and has thus become the symbol of
modernization for railway transportation. However electrified railways,
which include traction power supply systems, electric locomotives,
and their maintenance systems,
also require a large investment,
exhibit electromagnetic interference, and face many other problems. A traction railways substation,
traction network, and electric locomotive constitute a closed traction
power supply circuit, as shown in
Figure 1. The following section
introduces three main aspects: the

Electrified Railway
Power Supply System

The objectives of high-speed train transportation management are to use existing technology, equipment, and manpower to maintain the safe handling of high-speed trains
and complete the entire transportation process smoothly
according to the established organizational plan. The following section introduces three
main parts of high-speed train
transportation management in
Distribution System
Power Station
detail: the traction power supply
Transmission Line
system for electrified railways, the
Users
transportation organization mode,
Generator Step-Up Transformer
and the high-speed train operation
Step-Down Transformer
control system.
Dedicated High-Voltage
Transmission Line

110 kV
Traction
Substation

(Traction) Power
Supply System

Return Line

Neutral Zone

Feeder

Overhead
Lines 27.5 kV
Rail

TCMS
TCU

10
9

1) Pantograph
2) Main
Circuit Breaker

Traction Motor
4

3) Traction Transformer

5

Four-Quadrant Intermediate
Converter
Circuit

6
Inverter

7
Transmission 8

Figure 1. The traction power supply system for electrified railways. TCMS: Train Control and
Management System; TCU: traction control unit.

	

IEEE Electrific ation Magazine / S EP T EM BE R 2 0 1 9

67
IEEE Electrification - September 2019

Table of Contents for the Digital Edition of IEEE Electrification - September 2019
