GB/T 24338.1-2018Railway applications -- Electromagnetic compatibility -- Part 1: General (English PDF)

Foreword

GB/T 24338 "Railway applications - Electromagnetic compatibility" consists of

the following parts.

- Part 1. General;

- Part 2. Emission of the whole railway system to the outside world;

- Part 3-1. Rolling stock - Train and complete vehicle;

- Part 3-2. Rolling stock - Apparatus;

- Part 4. Emission and immunity of the signalling and telecommunications

apparatus;

- Part 5. Emission and immunity of fixed power supply apparatus and

systems.

This Part is Part 1 of GB/T 24338.

This Part is drafted in accordance with the rules given in GB/T 1.1-2009.

This Part replaces GB/T 24338.1-2009 "Railway applications - Electromagnetic

compatibility - Part 1. General". As compared with GB/T 24338.1-2009, the

main technical changes are as follows.

- MODIFY the instructions that this Part shall be used in conjunction with

other parts of GB/T 24338 (SEE Chapter 1; Chapter 1 of the 2009 version);

- ADD a normative reference. GB/T 28807 (SEE Chapter 2);

- ADD the requirement that possible electromagnetic interference shall be

considered when adding auxiliary apparatus to railway system (SEE

Chapter 5);

- ADD the requirement of management of electromagnetic compatibility

between rolling stock and train detection systems (SEE Chapter 5);

- MODIFY the composition of electric traction power supply system (SEE A.5;

A.5 of the 2009 version);

- ADD a description of the manner in which the track circuit detects whether

there is a train (SEE A.7.5);

- DELETE the Appendix B "Electromagnetic compatibility management of the

interface between railway infrastructure and train" (SEE Appendix B of the

Introduction

GB/T 24338 (all parts) is used for electromagnetic compatibility management,

also specifies the limits and measurement methods for the electromagnetic

emission of the railway system as a whole to the outside world, and the limits

of electromagnetic emission, immunity level, performance criteria, and

measurement methods of railway apparatus. The electromagnetic emission

level of the apparatus is compatible with the emission limits of the whole railway

system, which is beneficial for apparatus applications in the whole railway

environment. There are different stationary emission limits set for trunk railways,

subways, and trams/trolleybuses. GB/T 24338 (all parts) is applicable to

frequencies ranging from 0 GHz~400 GHz. No tests need to be performed at

frequencies where no requirement is specified. GB/T 24338, through emission

limits and immunity level requirements, achieves electromagnetic compatibility

between the whole railway system and the outside world, as well as between

various types of apparatus in the railway system.

The compatibility between the railway system and the outside world is related

to the emission limits of railway system, which shall be set in consideration of

the measurement results. Assuming that the compatibility between the railway

system and the outside world is satisfactory after the measurements are

completed, and it is confirmed that the measurement results related to the limits

are acceptable, the rail system has satisfactory compatibility. The emission

limits and immunity level requirements do not ensure electromagnetic

compatibility between the rail system and the outside world. In exceptional

circumstances, for instance near a special location which has unusual

electromagnetic interference, the railway system may require additional

measures to be taken to ensure proper compatibility. In special circumstances,

particular care shall be taken when in proximity to special transmitting

equipment such as radio frequency transmitter, or military/medical launchers.

In particular, attention is drawn to any magnetic imaging equipment in hospitals

which may be near to urban transport. The interested parties may consult and

cooperate to achieve electromagnetic compatibility.

The emission limits and immunity levels also do not ensure that the integrated

devices of the electric apparatus in railway system meet the requirements. GB/T

24338 does not cover all possible system compositions, but applies to most

apparatus. In exceptional circumstances, for instance near a special location

which has unusual electromagnetic interference, the railway system may

require additional measures to be taken to ensure proper operation. The

resolution of this is a matter for discussion between the apparatus supplier and

the project manager, infrastructure controller or equivalent.

Railway electric apparatus can form large systems (SEE Appendix A), such as

Railway applications - Electromagnetic compatibility -

Part 1. General

1 Scope

This Part of GB/T 24338 specifies the structure and content of other parts of

GB/T 24338.

This Part specifies performance criteria which apply to the whole standard.

Chapter 5 gives information on electromagnetic compatibility management.

The use of this Part alone is insufficient to judge whether the basic requirements

of the electromagnetic compatibility specification are met. It shall be considered

in conjunction with other parts of GB/T 24338.

Appendix A gives the characteristics of a railway system which has an impact

on electromagnetic compatibility behaviour.

This Part does not include the following phenomena. nuclear electromagnetic

pulse, abnormal operating conditions, and the induction effects of direct

lightning strike.

The emission limits specified in this Part do not apply to intentional transmitters

within the railway system.

Safety considerations are not covered by this Part.

This Part does not consider the biological effects of non-ionizing radiation and

apparatus for medical assistance (e.g., pacemakers).

2 Normative references

The following documents are indispensable for the application of this document.

For the dated references, only the versions with the dates indicated are

applicable to this document. For the undated references, the latest version

(including all the amendments) are applicable to this document.

GB/T 4365 Electrotechnical terminology - Electromagnetic compatibility

[GB/T 4365-2003, IEC 60050(161).1990, IDT]

GB/T 17799.2 Electromagnetic compatibility - Generic standards - Immunity

for industrial environments (GB/T 17799.2-2003, IEC 61000-6-2.1999, IDT)

- Electrostatic coupling, in which an electrostatic body is discharged to a

victim circuit;

- Capacitive coupling, in which the varying voltage in one circuit produces

voltage changes in a victim circuit via mutual capacitance;

- Inductive coupling, in which a magnetic field produced by a varying current

in one circuit, links with a victim circuit, inducing a disturbance voltage via

mutual inductance;

- Conductive coupling, in which the source and victim circuits share a

common conduction path;

- Electric and magnetic radiation, in which the circuit structures act as

antennas transmitting and receiving energy.

A.3 Principal electromagnetic phenomena for immunity

A.3.1 Low frequency conduction

A.3.1.1 Slow variations of the supply voltage including dips, surges, fluctuations,

unbalance.

A.3.1.2 Harmonics and intermodulation components.

A.3.1.3 Data transfer carried on the power supply.

A.3.1.4 Power frequency variations, induced low frequency voltages and DC

component in AC networks.

A.3.2 Low frequency field

Steady/transient magnetic fields and electric fields.

A.3.3 High frequency conduction

Unidirectional and oscillatory transient physical quantities (e.g., single or

repetitive bursts) and induced currents.

A.3.4 High frequency radiation

Magnetic fields, electric fields, and radio frequency radiated waves.

A.4 Principal electromagnetic phenomena for emission

The principal electromagnetic phenomena associated with immunity are also

related to emissions, but only limit requirements are imposed on the following.

a false indication of clear track. Track circuits take many forms of frequency and

time coding to reduce the risk of false energization.

The power supply may contain voltage components at track circuit frequencies,

and the input impedance of the train shall be greater than a specified value.

This prevents the passage of currents at track circuit frequencies forming in the

rails. The traction and auxiliary apparatus of the vehicle and the substations

shall not generate currents at track circuit frequencies which exceed specified

values. In special circumstances, limits shall be considered. For the railway,

these effects are entirely internal and come in many different forms.

A.7.6 Trackside apparatus

Electric energy is used in trackside apparatus to drive motors, heating, train

pre-heating, as well as other apparatus. Although the power is relatively low,

they are close to the line and may affect other railway apparatus.

A.8 Summary of main characteristics of railways

The essential differences between railways and other large electric networks

are.

- A wide variety of power supply configurations;

- A wide variety of control systems, subsystems, and power use;

- The use of sliding contacts to convey high powers to the moving trains;

- High speed operation of the trains;

- The presence of several moving sources of noise at the same time;

- A fluctuating and difficult-to-measure current flow to and from the train,

including the passage of current via the ground;

- High-power single phase loads, which may cause imbalance in the three

phase system;

- The possibility of simultaneous generation of disturbance from several

sources of noise;

- Generation of electromagnetic noise over a wide frequency spectrum;

- The power supply interacts with the vehicles, the effect of which is

enhanced or diminished at a given frequency point.

A.9 External sources of disturbance

......