la protection s élective des r éseaux électriques - accueil · first objectives of the...

La protection sélective des réseaux électriques. .ULG 21 11 2012

ULg 21/11/2012

© Siemens AG 2006Power Transmission and DistributionA.Belvaux

The T&D grids

Generation Transmission Distribution Industry

ULg 21/11/2012


The electricity network ensure an efficient supply of energy

High Voltage Transformers Medium VoltageComponents, switchgear and turnkey projects for AC and DC power

Components, switchgear and turnkey projects for AC and DC power

Power transformers, distributiontransformers with oil or cast-resin projects for AC and DC power

technology for power transmission ≤ 52 kV.

projects for AC and DC power technology for power transmission > 52 kV.

transformers with oil or cast-resininsulation.

ULg 21/11/2012


Energy AutomationNetwork control systems, protectionand substation automation, telecontrol systems, power quality.

ServicesNetwork planning & consulting, asset maintenance and maintenance management for grids and networks, metering services.

Energy flow in electricity networks

Main power stationMain power stationMain power stationMain power stationWindWindWindWind

HydroHydroHydroHydro

15 15 15 15 kVkVkVkV

150 150 150 150 kVkVkVkV

StorageStorageStorageStorage

CombinedCombinedCombinedCombinedindustrialindustrialindustrialindustrialprocessesprocessesprocessesprocesses

BiomassBiomassBiomassBiomass

Fuel cellFuel cellFuel cellFuel cell150 150 150 150 kVkVkVkV

15 15 15 15 kVkVkVkV

....0000 4 4 4 4 kVkVkVkV

++++ ----

ULg 21/11/2012


DomesticDomesticDomesticDomestic IndustryIndustryIndustryIndustry

....0000 4 4 4 4 kVkVkVkV

DomesticDomesticDomesticDomesticCombinedCombinedCombinedCombinedheat powerheat powerheat powerheat power

SolarSolarSolarSolar

StorageStorageStorageStorage ....0000 4 4 4 4 kVkVkVkV

Key Product for High VoltageNetwork: Circuit Breaker

63

50

40

Rated short-circuit breaking current [kA]

80

3AT2/3 3AT4/5

ULg 21/11/2012


31,5

25

072,5 123 145 300 362 420 550 800

Rated voltage [kV]170 245

3AP1 FI3AP1 FG 3AP2 FI

Coils� Air Core Dry Type

Reactors

Arrester� HV:

AIS (Porcellain, Polymer)

Products for High VoltageArrestors, Bushings, Coils & Instrument Transformer s

Instrument Transformers� Current Transformers

Bushings� Air Core Dry Type Reactors

Reactors� Line Traps� Arc Suppression Coils

AIS (Porcellain, Polymer) & GIS; HVDC, FACTS

� MV: Distribution & Traction Vehicles

ULg 21/11/2012


� Current Transformers� Voltage Transformers

� Air Core Dry Type Reactors� Line Traps� Arc Suppression Coils

Gas Insulated Switchgear (GIS) 8DN9 switchgear

�Rated voltage up to 245 kV

�Rated frequency 50 / 60 Hz

�Rated power frequency�Rated power frequency

withstand voltage (1 min) up to 460 kV

�Rated lightning impulse

withstand voltage (1,2/50 µs) up to 1050 kV

�Rated busbar current up to 3150 A

�Rated feeder current up to 3150 A

�Rated breaking current up to 50 kA

�Rated short-time current up to 50 kA

�Leakage rate per year and

ULg 21/11/2012


�Leakage rate per year and

gas compartment < 0.5 %

�Bay width 1500 mm

�Bay height 3500 mm

�Bay depth 4700 mm

�Bay weight 5 t

� High reliability

� Excellent field experience with more than 2

Medium Voltage ComponentsVacuum Tubes

million vacuum interrupters

� Tailormade development

� Wide product range for any application

� For use in

� LV and MV circuit-breakers, load-break

switches and contactors

ULg 21/11/2012


switches and contactors

� Autoreclosers

� Transformer Tap Changers

Delivery Program

690 up to 1300 V up to 65 kA up to 2500 A

7.2 up to 40.5 kV up to 72 kA up to 6300 A

Energy Automation

Do lor situs cum habilitarum itum alus causticus

� Information and network control technologyalus causticus

imanenter Status landum exus rius laudanum tum.

Lorem exit vulnareus plexus est. Vulna pausta rhus tex, per

technology

� Protection and substation auto-mation, telecon-trol systems, power quality

ULg 21/11/2012


pausta rhus tex, per itum falor sit wunt. Sit itum causticus aurum eum et expli ndus.Cum

-detect fault and isolate only the faulted part of the power system

First objectives of the „SELECTIVE PROTECTION“

-ensure the greatest possible level of the grid and supply reliability

-limit the effect of faults on the equipments (cabl e , transformer,..)

ULg 21/11/2012


LE SYSTEME DE PROTECTION =

TI/TP + Relais+ Disjoncteur

SIPROTEC 4

TI/TP + Relais+ Disjoncteur

Sélectif,rapide,fiable

ULg 21/11/2012


Reliability of the protection relays

X

1. Fast operation ⇒ Limit damages

R

ULg 21/11/2012


2. High accuracy ⇒ High selectivity

3. Signal distortion does not cause delay or maloperation

SIPROTEC more than 100 Years of Experience

1910 1960 1970 1980 1990 2000 2012

ULg 21/11/2012


Analog Relays

Electromechanical Relays

Numerical Protection Relays

O/C protection

ULg 21/11/2012


Time-overcurrent protection Functions

Time-overcurrent protection

Criteria for fault: overcurrent

Criteria for selectivity: time

ULg 21/11/2012


Time-overcurrent protection Characteristics

Tripping characteristic of a two stage time-overcur rent protection device - definite time

t [sec]

1.0

1.5

2.0

Tripping area

protection device - definite time

ULg 21/11/2012


0.5

x IN0.5 1.0 1.5 2.0 2.5I> I>>

Time-overcurrent protection Application

Main protection as line protection

x x x x

O/C O/C O/C O/C

t = 0mst = 300mst = 600mst = 900ms

Ttripbackup

ULg 21/11/2012


Advantage: simple device,only current transformers are necessary

Disadvantage: near infeed higher tripping time

distance

up

Distance protectionDistance protection

ULg 21/11/2012


Why impedance protection?

Situation: Meshed network and two infeedsDirectional overcurrent time relays

0,6s

0,6s

0,3s

0,3s

ULg 21/11/2012


0,6s

0,6s

0,3s

0,3s

non-selective trip

Localization of short-circuits by means of an impedance measurement:

� fault on the protected line Z1

Basic principle of impedance protection

� fault on the protected line

� fault outside the protected line

Z1

relay A

relay A

Z2

ULg 21/11/2012


selectivity

Distance measurement (principle)

ZL = RL + j XLIL1

IL2

Z

L

6 loops: 3 phase- phase loops and3 phase- ground loops

phase- phase -loop:

ZE = RE +j XEIL3

IE Z

EUL1UL2UL3

ULg 21/11/2012


phase- phase -loop:

The same applies to the remaining loops

UL1-L2 = ZL ( IL1 - IL2)

Measured currentmeasured voltage

06.08.97dtgerdis3

Distance measurement (principle)

IL1

IL2

ZL

ZL = RL + j XL

phase-ground-loop: UL1 = ΙL1 · ( RL + j XL )- ΙE · ( RE +j XE)

IL2

IL3

IE Z

EUL1UL2UL3

ZL = RL + j XL

ZE = RE +j XE

ULg 21/11/2012


ΙL1, ΙE measured currentUL1 measured voltage

06.08.97dtgerdis3

The same applies to the remaining loops

UU tjj eUeUU ωϕ ⋅=⋅=

Impedance calculation using U- and I-phasors

R Z

II tjj eIeII ωϕ ⋅=⋅=

II t⋅=ωϕ

UU t⋅=ωϕ

0=t

IUZ ϕϕϕ −=

( ) XjRjZeZZ ZZj Z ⋅+=⋅+⋅=⋅= ϕϕϕ sincos

X

ULg 21/11/2012


( ) ( ) ( )IUIUj

j

j

I

Uj

I

Ue

I

U

eI

eU

I

UZ IU

I

U

ϕϕϕϕϕϕϕ

ϕ

−+−⋅=⋅=⋅⋅== − sincos

R X

Numerical filtered phasor measurement

X

1. Fast operation ⇒ Use short data window

R

ULg 21/11/2012


1. Fast operation ⇒ Use short data window



ni2sin ⋅π

Fourier analysis of measured values

Sampled

C(k)S(k)(k) j III ⋅+=S(k)I

C(k)Ij ⋅ )(kI

)( inki +−

k-n

0 1 2 . . . n

i

C(k)Ik

Sampledmeasuring values

Resulting phasor

ULg 21/11/2012


ni2cos ⋅π

C(k)Ij ⋅

ϕS(k)I

Load and short-circuit impedances

ZL

ZLF1

ZLF2

distance relayoperating characteristic

RF RF

ZLoadDF1 F2

X

ZL

ZLF2

j L

RR

ZF1

ZF2

RR

ZLoad

ZLF1

Fault area

Phase - Phase Fault

RR ≈ RF / 2

Phase - Earth Fault

ULg 21/11/2012


Rj SC1

j SC2

j L

Fault in reverse

direction Load area

Minimum Load Impedance:Minimum voltage 0,9 UnMaximum current 1,1 InMaximum angle ± 30°

RR ≈ RF /(1 + RE/RL)

X

Z5

Line

Impedance zones of digital relays

Distance zones

Inclined with line angle ϕAngle α prevents overreach of

R

ϕϕϕϕ LoadLoad

Z1

Z2

Z4

Z1B

Z5

αααα

Angle α prevents overreach of Z1 on faults with fault resistance that are fed from both line ends

Fault detection

no fault detection polygon: the

ULg 21/11/2012


Z3

no fault detection polygon: the largest zone determines the fault detection characteristic

simple setting of load encroachment area with Rmin and ϕLoad

Graded distance zones

time t3Z2

Z3

∆t = grading time

D1 D2 D3

t1

t2Z1

distance

A CB D

Grading rules:

ULg 21/11/2012


Z1 = 0,85 ZAB

Z2 = 0,85 (ZAB + 0,85 ZBC)Z3 = 0,85 (ZAB + 0,85 (ZBC + 0,85 ZCD))

Safety margin is 15 %:� line error� CT, VT error� measuring error

Grading rules:

Ring feeder: with grading against opposite end

0.6

grading time(s)0.6

0.3

ULg 21/11/2012


The same grading from both sides

Differential protection

ULg 21/11/2012


I1

Measuring Principle

Lines and Cables

I2

I

I5

Lines and Cables

Busbar

Transformer

Generator

ULg 21/11/2012


Kirchhoff: I1+I2+I3+I4+I5=0

I3

I4Motor

Line differential protection

over 3 line ends

7SD52

ULg 21/11/2012


7SD52

7SD52

No restrictions for communicationNo restrictions for communication

� Communication with …

� direct FO connection up to 100 km

� digital communication network (G703, X21)

� ISDN-connection

� 2 or 3 wire pilot wire (twisted, screened)

FO

or

ULg 21/11/2012


Digitalcommunication network

or7SD

5

ISDN

or2/3 wire pilot wire (Cu)

or

7SD

5OEEO

EO

EO

OE

OE

Transformer differential protection

UN1 = 110kV UN2 = 30kV

SN = 100MVA

IP1 = 500A(load current)

IP2 = 1833A(load current)

1000/5A 2000/5A

winding 1 winding 2

7UT512

IN, Trafo = 525A IN, Trafo = 1924A

IS1 = 2.5A IS2 = 4.58A measuredsecondary currents

ULg 21/11/2012


IDiff = ? IStab= ?

Method of Vector Group Determination

Side 2: Side 1:

1L12L1

2L2

IL1,S1IL1,S2 = IL1 - IL2

1L2

1L3

2L2

2L3

ULg 21/11/2012


330°(n * 30°)

Vector group is

Y d 11

Current transformer saturation

Saturation during steady-state current

ULg 21/11/2012


Saturation during offset current

Idiff fault line (k=1)

Ideal internal fault

� Idiff = I1

Trip Characteristic

Idiff fault line (k=1)

internal fault

external fault oroperation condition

� Idiff = I1

� Istab = I1

� fault is on fault line

External fault

� Idiff = 0

ULg 21/11/2012


Istab

� Istab = |I1|+|I2|+...|In|

security for CT deviations

X X X X

Busbar protection - summation transformer version

X

1

X

2

X

3

X

7

. . .

100 mA

ULg 21/11/2012


Summation transformer 4AM5120

Distributed System

substation

central unit

.

terminal panel terminal panel terminal panel terminal panel

22 22

fibre optics

1,5 km

bay unit

ULg 21/11/2012


50

terminal panel

50

terminal panel

50

terminal panel

50

terminal panel

Reliability of the protection relays

X

1. Fast operation ⇒ Limit damages

X

R

ULg 21/11/2012




Power System Influencesi1

t

i1

t

Inrush currents

Transformer overexcitation

CT saturation

t/s0,995 1,000 1,005 1,010 1,015 1,020 1,025 1,030 1,035 1,040 1,045 1,050

U/V

-100

-50

0

50Non system frequent voltages with capacitive voltage transformers

-XC

Leitung

R

X

-XC

Leitung

R

X

Variable system impedances with FACTS

GAP

MOV

ZS

GAP

MOV

ZS

Sub-synchronous frequencies with series compensation

ULg 21/11/2012


High equipment and route capacity

utilization

i/kA

t/ms500

u/kV

t/ms500

200

-3

6

3

i/kA

t/ms500

u/kV

t/ms500

200

-3

6

3

Power swings

Inter-area oscillations

la protection s élective des r éseaux électriques - accueil · first objectives of the...

Documents