BUILDING A LOW COST LISN FOR EMI TESTS

V Conferência de Aplicações Industriais

BUILDING A LOW COST LISN FOR EMI TESTS

Presenter: Fernando Soares dos Reis

Pontifical Catholic University of the Rio Grande do SulPontifical Catholic University of the Rio Grande do Sul

BrazilBrazil


Table of Contents

INTRODUCTION INTRODUCTION

OBJECTIVES OBJECTIVES

TERMS AND DEFINITIONS - EMC, EMITERMS AND DEFINITIONS - EMC, EMI

CONDUCTED EMICONDUCTED EMI

LINE IMPEDANCE STABILIZATION NETWORKLINE IMPEDANCE STABILIZATION NETWORK

PRACTICAL IMPLEMENTATIONPRACTICAL IMPLEMENTATION

EXPERIMENTAL RESULTSEXPERIMENTAL RESULTS

CONCLUSIONSCONCLUSIONS


Some examples of problems caused by EMI: Some examples of problems caused by EMI:

Pistol Drill may Interfere on TV;Pistol Drill may Interfere on TV; Electronic Ballast's may change the TV Electronic Ballast's may change the TV channel;channel; Switching Inductive Load may generate Switching Inductive Load may generate noise in Radios;noise in Radios;

Necessity of accordance with Standards...Necessity of accordance with Standards...

INTRODUCTIONINTRODUCTION


The simulation toolThe simulation tool


SSimulation imulation TToolool Results Results


Experimental ResultsExperimental Results


In this paper will be presented a methodology for In this paper will be presented a methodology for implementation of a Line Impedance Stabilization implementation of a Line Impedance Stabilization Network - LISN, symmetric commutable, in Network - LISN, symmetric commutable, in accordance with the specifications of the accordance with the specifications of the Normative IEC CISPR 16-1, using easily acquirable Normative IEC CISPR 16-1, using easily acquirable components in the electro-electronic stores. The components in the electro-electronic stores. The Line Impedance Stabilization Network is used for Line Impedance Stabilization Network is used for conducted EMI tests in equipment’s witch current conducted EMI tests in equipment’s witch current is not above 16 A.is not above 16 A.

OBJECTIVESOBJECTIVES


TERMS AND DEFINITIONSTERMS AND DEFINITIONS

Electromagnetic Compatibility - EMC:Electromagnetic Compatibility - EMC:

• It´s the characteristic presented by an It´s the characteristic presented by an equipment, or system, working equipment, or system, working satisfactorily, in an electromagnetic satisfactorily, in an electromagnetic environment without causing or environment without causing or suffering unacceptable degradation in suffering unacceptable degradation in its individually designed function.its individually designed function.


COMMUNICATIONCOMMUNICATION ENVIRONMENTENVIRONMENT


Electromagnetic Interference – EMIElectromagnetic Interference – EMI

Any electromagnetic disturbance that Any electromagnetic disturbance that interrupts, obstructs, or otherwise degrades or interrupts, obstructs, or otherwise degrades or limits the effective performance of limits the effective performance of electronics/electrical equipment. It can be electronics/electrical equipment. It can be induced intentionally, as in some forms of induced intentionally, as in some forms of electronic warfare, or unintentionally, as a electronic warfare, or unintentionally, as a result of spurious emissions and responses, result of spurious emissions and responses, intermodulation products, and the like. Also intermodulation products, and the like. Also called radio frequency interference RFI.called radio frequency interference RFI.

TERMS AND DEFINITIONSTERMS AND DEFINITIONS


INDUSTRIAL ENVIRONMENTINDUSTRIAL ENVIRONMENT


By Globalization´s By Globalization´s Highway...Highway...International Rules...International Rules...

ALCAALCA

MERCOSULMERCOSUL

EUROPEAN UNIONEUROPEAN UNION


IECIEC - International Electrotechnical Commission; - International Electrotechnical Commission; CISPRCISPR - International Special Committee on - International Special Committee on

Radio Interference;Radio Interference; CENELECCENELEC - Committee for Electrotechnical - Committee for Electrotechnical

StandardizationStandardization;; These organizations prepares and These organizations prepares and

publishes international standards for all electrical, publishes international standards for all electrical, electronic and related technologies;electronic and related technologies;

GLOBALIZATIONSGLOBALIZATIONS


CONSUMERS REQUIREMENTSCONSUMERS REQUIREMENTS

ELECTRONICS LOADSELECTRONICS LOADS

IN THE LAST YEARS THE ELECTRONIC LOADS GROW IN THE LAST YEARS THE ELECTRONIC LOADS GROW

UP OVER THE WORLDUP OVER THE WORLD

BRAZIL WAS NOT AN EXEPTION AT THIS PROCESSBRAZIL WAS NOT AN EXEPTION AT THIS PROCESS

IN THE LAST YEARS THE ELECTRONIC LOADS GROW IN THE LAST YEARS THE ELECTRONIC LOADS GROW

UP OVER THE WORLDUP OVER THE WORLD

BRAZIL WAS NOT AN EXEPTION AT THIS PROCESSBRAZIL WAS NOT AN EXEPTION AT THIS PROCESS


ELECTROMAGNETIC COMPATIBILITY

EMISSION SUSCEPTIBILITY

CONDUCTED IRRADIATED CONDUCTED IRRADIATED

ELECTROSTATIC

HARMONICSPOWER

FLUTUATION RADIO-INTERFERENCE

Basic Categories for EMCBasic Categories for EMC


Difficulties for realization of the testsDifficulties for realization of the tests

Few test Facilities (in Brazil and South America);Few test Facilities (in Brazil and South America);

Test apparatus are very expensive;Test apparatus are very expensive;

Technical Capacity;Technical Capacity;

Standards Interpretation;Standards Interpretation;

Conducted EMI testConducted EMI test


EMCEMC

Interference MeasurerEMI Receptor

10 kHz to 30 MHzAccording to VDE 0871

Uinter..

LISN

450 kHz a 30 MHzAccording to FCC 15

Telescopic AntennaLoop Antenna

Dipole Antenna

30 to 1000 MHz

Interferencesupply

According to VDE 0871 e FCC

10 kHz to 30 MHzAccording to VDE 0871

Not Required by VDE

Einter..

Hinter..

Pinter..

Iinter...

Line Impedance Stabilization Network


2 X

E U T Antenna

3 XX

Open Area Test SiteOpen Area Test Site


Ground Plane

EUT Antenna4 m

1 m

3 m10 m30 m

1 m

EMI

Receiver

100 m

IRRADIATED EMI MEASURING PROCEEDINGSIRRADIATED EMI MEASURING PROCEEDINGS


CISPR 11CISPR 11

LIMIT STANDARDSLIMIT STANDARDS

FCC 15FCC 15

8080

7070

6060

Limit ValueLimit Valueclass Aclass A

class Bclass B

7070

6060

dBdB

µVµV

100100

9090

MHzMHz0.010.01 0.10.1 11 1010 30301.61.60.450.45

5050

4040

3030

4848

Limit ValueLimit Value

Class AClass A. A device that is marketed for use in a commercial, . A device that is marketed for use in a commercial, industrial or business environment; industrial or business environment;

Class BClass B A device that is marketed for use in a residential A device that is marketed for use in a residential environment notwithstanding use in commercial, business and environment notwithstanding use in commercial, business and industrial environments;industrial environments;

0.15 0.5 30 MHz

100

90

80

70

60

50

40

300.9 10

73

6066

79

56

Limit Value Limit Value Quasi-peak (class A)Quasi-peak (class A)

dBµV

Quasi-peak (class B)Quasi-peak (class B)


It is the part of the electromagnetic interference It is the part of the electromagnetic interference

that flows by power cords.that flows by power cords.

This kind of interference can be propagated in:This kind of interference can be propagated in:

Differential Mode (DM) or inDifferential Mode (DM) or in Common Mode (CM)Common Mode (CM)

CONDUCTED EMICONDUCTED EMI


EquipmentEquipment

ZZ LISNLISN

PhasePhase

NeutralNeutral

ii CDMCDM

CONDUCTED EMI IN CONDUCTED EMI IN DIFERENTIAL MODEDIFERENTIAL MODE


EquipmentEquipment

ZZ LISNLISN iiCCMCCM

CONDUCTED EMI IN CONDUCTED EMI IN COMMON MODECOMMON MODE

PhasePhase

NeutralNeutral

Ground - CommonGround - CommonParasitic CapacitorsParasitic Capacitors


Conductive Surface Connected to GndConductive Surface Connected to Gnd

Equipment Under TestEquipment Under Test

LISNLISN

EMI ReceiverEMI Receiver

80 cm80 cm8080

cmcm

4040cmcm

Equipment Under Test (EUT) and Equipment Under Test (EUT) and Measurements Apparatus Measurements Apparatus

LABORATORY TESTS FACILITIESLABORATORY TESTS FACILITIES

Layout for conducted emissions testsLayout for conducted emissions tests


EMI ReceptorEMI Receptor

80 cm80 cm8080

cmcm

4040cmcm

Frequency (MHz)Frequency (MHz)

Imp

edan

ce

Imp

edan

ce

± 20 % Maximum Tolerance± 20 % Maximum Tolerance

kHz

10

10000

5,4

50

20

80

150

300

800

7,3

21

33

43

49

LISNLISN Fre. Imp.

50µH

50

5

SIMULATION OF THE SIMULATION OF THE LISN CHARACTERISTICSLISN CHARACTERISTICS

CISPR 16

LISNLISN


IMPLEMENTED LISN IMPLEMENTED LISN

EMI

Reveiver

To The EUT

4 µF 8 µF250 nF50 µH

Gnd

4 µF8 µF

250 nF50 µH

50

Phase

Mains

Neutral

To The EUT

1 k

1 k

250 µH

5

5

250 µH


Inductor of the 50 Inductor of the 50 HH



The inductor is a coil with 35 turns, shaping one only layer of 6mm enameled wire. The step of this coil is 8 mm, rolled in an isolating core of (150 mm) 130 mm or 5 inches x 280 mm as the IEC CISPR 16-1 regulations indicates. The wire diameter is the dimension that considers to minimize the inductors resistive component. However, the coil built was fashioned using a 4 mm wire, because the current from the test equipment's is under 5A.



The step rolling control of the inductor was made using a 4 mm fishing string (nylon) between each espire.



To suppress internal resonance in this inductor the IEC CISPR 16-1 regulation, establishes that 430 ± 10% being connected between the espires 4 and 8, 12 and 16, 20 and 24 and 26 and 32 as showed.



To obtain a 430 resistance, which is not commercial it was associated in parallel a

470 resistor with another of 4700 .


LISN Assembled on a PC RackLISN Assembled on a PC Rack


EXPERIMENTAL RESULTSEXPERIMENTAL RESULTSLISN - EXPERIMENTAL RESULTSLISN - EXPERIMENTAL RESULTS

Regulation

Phase

Neuter

Zmin

Zmax


The mainly point of this work is in the fact The mainly point of this work is in the fact

of making more accessible the EMI tests of making more accessible the EMI tests

realization, diminishing the assembling realization, diminishing the assembling

costs in EMI test facilities, reflecting even costs in EMI test facilities, reflecting even

by academic or industrial environment.by academic or industrial environment.

The mainly point of this work is in the fact The mainly point of this work is in the fact

of making more accessible the EMI tests of making more accessible the EMI tests

realization, diminishing the assembling realization, diminishing the assembling

costs in EMI test facilities, reflecting even costs in EMI test facilities, reflecting even

by academic or industrial environment.by academic or industrial environment.



The components utilized to build the The components utilized to build the

Artificial Network are easily acquired, Artificial Network are easily acquired,

because they are not specific for this usage.because they are not specific for this usage.

The only problem to use Artificial Networks The only problem to use Artificial Networks

is the calibration factor. is the calibration factor.

The components utilized to build the The components utilized to build the

Artificial Network are easily acquired, Artificial Network are easily acquired,

because they are not specific for this usage.because they are not specific for this usage.

The only problem to use Artificial Networks The only problem to use Artificial Networks

is the calibration factor. is the calibration factor.



The End

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BUILDING A LOW COST LISN FOR EMI TESTS