Electromagnetic Compatibility

Grzegorz Kosobudzki

; Jerzy Leszczyński

Introduction to EMC

Electromagnetic compatibility (EMC)

the ability of a system or equipment to operate within

design tolerances in its intended environment, with
adjacent systems and equipment, and with itself, so
that the effect of any electromagnetic disturbances
produced by the systems or equipment is reduced.

2

Electromagnetic compatibility (EMC)

Equipement,

Device or

System

Intrasystem

interference

Electromagnetic

disturbances

Electromagnetic

environment

Electromagnetic

disturbances

emmision

Electromagnetic

environment

3

Electromagnetic compatibility (EMC)

Electromagnetic

Compatibility

Electromagnetic

emission

Electromagnetic

susceptibility

4

Electromagnetic interference (EMI)

A phenomenon in which electronic devices upset

each other’s operation. Computers, television
receivers, telephone sets, high-fidelity sound
equipment, and certain medical devices can
malfunction because of strong radio-frequency
fields such as those from a nearby broadcast
transmitter. The EMI is usually the result of
improper or ineffective shielding in the affected
device or system.

5

Electromagnetic compatibility

frequency range

 DC
 Power line frequency 50,60,400 Hz
 Low frequency 50…150kHz
 High frequency >150kHz (Radio frequency)

6

The electromagnetic interference (EMI)

coupling channel

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Source of

electromagnetic

disturbances

Victim

(equipment)

Coupling path

Electromagnetic

(Radiative)

Common impedance (Conductive)
Magnetic field

(Inductive)

Electric field

(Capacitive)

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Principal phenomena causing electromagnetic disturbances as classified by the IEC

Group

Exemples

Conducted low frequency phenomena Harmonic, interharmonic, DC in AC networks

Signal system (power line carrier)

Voltage dips, interruption,fluctuation, imbalance

Power frequency variation

Induced low frequency voltages

Radiated low frequency phenomena

Magnetic fields, Electric fields

Conducted high frequency
phenomena

Induced continuous wave voltage or current

Oscillatory transient, Unidirectionat transient

Radiated high frequency phenomena

Magnetic fields, Electric fields, electromagnetic fields

Transients, continuous waves

Electrostatic discharge (ESD)

Nuclear electromagnetic pulse (NEMP)

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Conductive interference

Power Supply

Temperature

sensor

Vo=10mV/

o

C

Vcc

+5V

GND

LOAD

V

m

V

m

=V

o

+V

AB

A

B

I

on

=1A

Shared current path

9

Conductive interference

Power Supply

Temperature

sensor

Vo=10mV/

o

C

Vcc

+5V

GND

LOAD

V

m

V

m

=V

o

A

I

on

=1A

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Inductive interference

R

L

Vs - Signal source

Vn - Noise source

Magnetic flux coupling

I

n

M

R

L

Vs

Vn

11

Capacitive interference

R

L

Electrical field

Vs - Signal source

Vn - Noise source

R

L

Vs - Signal source

C

ef

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Emission limit,immunity limit, compatibility level

and planning level

P

ro

b

a

b

ili

ty

d

e

n

s

it

y

Disturbance level

Emission

Level

Compatibility

Level

Equipement

Compatibility

Level

Immunity

Limit

Planning

Level

Emission

Limit

13

Emission limit,immunity limit, compatibility level

and planning level

D

is

tu

rb

a

n

c

e

L

e

v

e

l

Independent variable

Compatibility Level

Emission Limit

Immunity Limit

Emission Level

Immunity Level

Immunity Margin

Emission Margin

Compatibility Margin

Construction Emission

Margin

Construction Immunity

Margin

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Power Quality – Part of EMC

Power Quality: The concept of powering and
grounding electronic equipment in a manner that
is suitable to the operation of that equipment and
compatible with premise wiring system and other
connected equipment

IEEE std 1159 definition

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Power Quality – Part of EMC

Coupling path

– conductive (Power Distribution System )

Equipement: Immunity to disturbances in power system

Emission of disturbances to power system

Environment: power system voltage parameters

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How to prevent disturbances?

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•Use shielded gaskets to seal doors and
flanges
•Fit an EMC filter on the incoming power side
•Keep signal cables away from power cables
•Use screened cables and use EMC glands for
360 degree earth bonding on both ends

Electromagnetic compatibility

Overview of Standards (IEC 61000 series)

• 1: General : General consideration (fundamental principles).
• 2: Environment : Description and classification of environment.

Compatatibility levels.

• 3: Emission limits and immunity test levels.
• 4: Testing and measurement techniques.
• 5: Installation and mitigation guidelines.
• 6: Generic standards.
• 9: Miscellaneous.

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Enviroment

• EN 61000-2-2 - Compatibility levels for low-frequency conducted

disturbances and signalling in public low-voltage power supply
systems.

• EN 61000-2-4 - Compatibility levels in industrial plants for low-

frequency conducted disturbances.

• EN 61000-2-9 - Description of HEMP environment - Radiated

disturbance. Basic EMC publication.

• EN 61000-2-10 - Description of HEMP environment - Conducted

disturbance.

• EN 61000-2-12 -Environment - Compatibility levels for low-frequency

conducted disturbances and signalling in public medium-voltage
power supply systems.

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Limits

• EN 61000-3-2 - Limits for harmonic current emissions (equipment

input current ≤16 A per phase) .

• EN 61000-3-3 - Limitation of voltage changes, voltage fluctuations

and flicker in public low-voltage supply systems, for equipment with
rated current ≤16 A per phase and not subject to conditional
connection.

• EN 61000-3-11 - Limitation of voltage changes, voltage fluctuations

and flicker in public low-voltage supply systems - Equipment with
rated current ≤ 75 A and subjet to conditional connection.

• EN 61000-3-12 - Limits for harmonic currents produced by equipment

connected to public low-voltage systems with input current > 16 A
and ≤ 75 A per phase.

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Testing and measurement techniques-1

• EN 61000-4-2 - Electrostatic discharge immunity test.
• EN 61000-4-3:2006 - Radiated, radio-frequency,

electromagnetic field immunity test.

• EN 61000-4-4:2004 - Electrical fast transient/burst

immunity test.

• EN 61000-4-5 –Surge immunity test.
• EN 61000-4-6 -Immunity to conducted disturbances,

induced by radio-frequency fields.

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Testing and measurement techniques-2

• EN 61000-4-8 - Power frequency magnetic field immunity test.
• EN 61000-4-9 - Pulse magnetic field immunity test.
• EN 61000-4-10 - Damped oscillatory magnetic field immunity test.
• EN 61000-4-11 - Voltage dips, short interruptions and voltage

variations immunity tests .

• EN 61000-4-34 - Voltage dips, short interruptions and voltage

variations immunity tests for equipment with input current more
than 16 A per phase.

• EN 61000-4-14 - Voltage fluctuation immunity test for equipment

with input current not exceeding 16 A per phase.

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Testing and measurement techniques-3

• EN 61000-4-13 - Harmonics and interharmonics including mains

signalling at a.c. power port, low frequency immunity tests.

• EN 61000-4-12 - Ring wave immunity test .
• EN 61000-4-18:2007 - Damped oscillatory wave immunity test
• EN 61000-4-16 - Test for immunity to conducted, common mode

disturbances in the frequency range 0 Hz to 150 kHz.

• EN 61000-4-17 - Ripple on d.c. input power port immunity test.
• EN 61000-4-20 - Emission and immunity testing in transverse

electromagnetic (TEM) waveguides.

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Testing and measurement techniques-4

• EN 61000-4-21 - Reverberation chamber test methods.
• EN 61000-4-23 - Test methods for protective devices for HEMP and

other radiated disturbances .

• EN 61000-4-24 - Test methods for protective devices for HEMP

conducted disturbance - Basic EMC Publication.

• EN 61000-4-25 - HEMP immunity test methods for equipment and

systems.

• EN 61000-4-27 - Unbalance, immunity test for equipment with input

current not exceeding 16 A per phase.

• EN 61000-4-28 - Variation of power frequency, immunity test for

equipment with input current not exceeding 16 A per phase .

• EN 61000-4-29 - Voltage dips, short interruptions and voltage

variations on d.c. input power port immunity tests

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Testing and measurement techniques-5

• EN 61000-4-7 - General guide on harmonics and

interharmonics measurements and instrumentation, for
power supply systems and equipment connected thereto.

• EN 61000-4-15 - Flickermeter - Functional and design

specifications.

• EN 61000-4-30 –Power quality measurement methods.

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Installation and mitigation guidelines

• EN 61000-5-5 - Specification of protective devices for

HEMP conducted disturbance. Basic EMC Publication.

• EN 61000-5-8 - HEMP protection methods for the

distributed infrastructure.

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Generic standards

• EN 61000-6-1 - Immunity for residential, commercial and

light-industrial environments.

• EN 61000-6-2 - Immunity for industrial environments.
• EN 61000-6-3 - Emission standard for residential,

commercial and light-industrial environments.

• EN 61000-6-4 - Emission standard for industrial

environments.

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International Electrotechnical

Commission

The IEC is the world's leading organization that prepares

and publishes International Standards for all electrical,
electronic and related technologies — collectively
known as „electrotechnology”

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CISPR

The Special International Committee on Radio

Interference (abbreviated CISPR from the French name
of the organization, Comité international spécial des
perturbations radioélectriques) is concerned with
developing norms for detecting, measuring and
comparing electromagnetic interference in electric
devices. Its members are partially also in the
International Electrotechnical Commission (IEC). It was
founded in 1934.

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References and useful links

• www.iec.ch
• www.pkn.pl
• www.lpqi.org
• www.schaffner.com -> www.teseq.com
• www.miedz.org.pl
• www.reo.co.uk
• www.emtest.com

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References and useful links

• C. Sankaran – ”Power quality” – CRC press 2002
• A.Baggini –”Handbook of Power Quality” – John Wiley &

Sons 2008

• R.C.Dugan, M.F. McGranaghan, H.W Beaty – „Electrical

Power System Quality”-McGraw-Hill 1996

• Kenneth L. Kaiser – „Electromagnetic Compatibility

Handbook” – CRC Press 2005

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