Generator Protection - Automation-Berlin

Generator Protection

Siemens LSA 2.5.5 . April 1995 1

Application

The 7UM516 is a numerical generatorprotection relay and is mainly used withlarger generation units. In most cases itis combined with other devices of the7UM51 and 7UT51 series, where severalfunctions can be implemented as redun-dant protection.

Construction

The unit incorporates in its compactconstruction all components for Acquisition and evaluation of

measured values Operator panel with display Event/alarm and command outputs Binary inputs Serial interfaces Auxiliary DC/DC converters.Three housing variants are available. Themodel for panel flush mounting or cubiclemounting has rear connection terminals.The model for panel surface mountinghas 100 screw terminals accessible fromthe front. A third variant for flush or cu-bicle mounting without glass cover isavailable.

Functions

The following protection functions areintegrated:

ANSI–No.: Impedance protection 21 Out–of–step protection 78 Reverse power protection 32R Forward power monitor 32 Unbalanced load protection 46 Earth–fault protection V0 > 64 Direct coupling (for separate protection

units).

Measurement method

The influence of harmonics, higher fre-quency transients, DC transient compo-nents and current transformer saturationeffects are extensively suppressed. Thisis achieved using a high performance mi-croprocessor and continuous digital sig-nal processing (measured value acquisi-tion, measured value conditioning andmeasured value processing).High measurement accuracy is achievedby the use of physical models forprocess imaging.The correct measurement is ensured byfilter adaptation even with deviationsfrom rated frequency (fN 10 Hz).

Serial interfaces

The unit is equipped with 2 serial inter-faces.The front serial interface is suitable forconnecting an AT–compatible PC. The PCbased program DIGSI can be used forconvenient and transparent setting, dis-turbance recording and evaluation as wellas commissioning (optional).The rear system interface is available al-ternatively as an isolated V.24(RS232) in-terface or as a fibre–optic interface forconnecting to the SINAUT LSA stationcontrol or to a protection data master unit(protocol to DIN 19 244).

Setting

All setting parameters can be input eithervia the integrated operator and displaypanel or a personal computer. Theparameters are written into non–volatilememory so that the setting valuesremain secure even during interruption ofthe supply voltage.

Self–monitoring

All important hardware and softwarecomponents are continuously monitored,irregularities in hardware and programsequence are detected and alarmed. Thissignificantly improves the security andavailability of the protection system.

7UM516 generator protection relay (Version V3)

Fig. 17UM516 generator protection

21

32

32R

46

64

Scope of functions

78

Siemens AG 1995


Siemens LSA 2.5.5 . April 19952

Impedance protection

This protection function operates asshort–circuit protection and simul-taneously takes over reserve protectionfunctions for the main protection orupstream series–connected protectionequipment (e.g. generator protection,transformer differential protection andnetwork protection).Fault detection is implemented with anovercurrent pick–up (with undervoltageseal–in) and initiates computation of theloop impedance. Depending on the vectorposition in the rectangular trippingcharacteristic, the time to operate is allo-cated (Fig. 2). The first–zone time t1should be set undelayed and the gradingtime t2 in accordance with the higher or-der protection.The first–zone trip is blocked automati-cally if tripping of the voltage transformermcb is detected via binary input, or apower swing is detected by a furtherintegrated algorithm.As a function of the particular switchingstate of the system, it is desirable to ex-tend the first zone reach or to re–routetrip signals. An additional impedancestage R1B, X1B or an additional logic trip-ping function can be activated via thebinary inputs.

Out–of–step protection

Depending on the network configurationstate and the infeed generators, powerswings can occur after disconnection ofshort circuits. If the centre of the powerswing falls within the unit this may leadto inadmissible loading of the generatorand requires disconnection from the net-work. On the other hand network–sidepower swings are less critical.The generator–related protection is basedon the proven impedance measurementprinciple and evaluation of the progressof the complex impedance vector. Fig. 3shows the power swing characteristics.Depending on characteristics, a numberof swings are permitted. Exceedingthereof causes a trip signal.Using the tilt of the characteristics it ispossible to achieve optimum adaptationto the particular system conditions.For purposes of external evaluation eachswing through the power swing charac-teristic is signalled.Activation of the protection function isperformed using the positive sequencecomponents of the current. At the sametime no negative sequence componentsmust exist.

Unbalanced load protection

This protection function detects un-symmetrical loading of three–phasemachines. It operates on the principle ofcomponent splitting and evaluates onlythe negative–phase sequence componentof the current.In the evaluation circuit a sensitive alarmstage 2 > and a course stage 2 areprovided. In addition the negative se-quence component of the current is fedinto a thermal replica where the corre-sponding heating of the rotor surface of agenerator is simulated (Fig. 4). For indica-tion (alarm) purposes an indication(alarm) relay can also be parameterizedto operate before the tripping limit of thethermal replica is reached.


Fig. 2 Characteristic of the impedance pro-tection (R1 0,4 XTr, X1 0,7 XTr; characteristicsX1B and R1B are activated via binary input)

X

R

X1B

R1B

t2

t1

t1b

R1

X1

Fig. 3Characteristic of the out–of–step tripping

P

Z TRIP

Z Make

Z TRIP

Characteristic 2

Im Z

Re Z

Z pos

Characteristic 1

Z Make

Fig. 4Instigation range of unbalanced load protection

Unbalanced loadWarning stage 2>

Thermalinstigation stage

Thermalwarning stage

tTWARN

T>>TRIP

2adm. 2>> 2

Unbalanced loadInstigation stage 2>>



Reverse power protection

If the driving energy of a generator fails,the generator continues on the networkas a motor and covers its friction lossesin the form of power withdrawal from thenetwork. This is undesirable from thenetwork and turbine viewpoint, andshould be terminated after a short periodby opening the generator circuit–breaker.Calculation of the effective power is per-formed using the positive sequence com-ponent vectors of current and voltage, sothat asymmetric network conditions donot lead to measurement errors. Inaddition it is possible to compensateangle errors of the current and voltageinstrument transformer by using a correc-tion angle.Optimized algorithms ensure high sensi-tivity.The state of the emergency trip valve canbe fed to the relay to control switchingbetween two delay times (long–timeshort–time).

Earth–fault protection

The main application is for the acquisitionof earth faults in the stator and on thegenerator terminals. With a high–ohmicor ungrounded generator in unit connec-tion the displacement voltage is eva-luated.By digital filtering of the input value, onlythe fundamental component is evaluated.Any harmonics (e.g. third harmonic) areeffectively suppressed.Appropriate dimensioning of the load re-sistor protects 90% of the stator winding(Fig. 5).

External signals

This enables the processing of signalsand commands from the Buchholz andother relays, which are fed to binary in-puts. External signals (up to 4) can beseparately time–delayed and marshalledlike a protection function.The advantages are in the trip signal pro-cessing and the precise timed event log-ging.

On–load measurement

The on–load measured values generatedin the unit such as current, voltage, fre-quency, active and reactive power, powerfactor, phase angle, resistance and reac-tance as well as negative sequence cur-rent can be displayed at the LC display orby means of a PC.

Fault event data

In a protection unit, depending on theparameterization, either the instanta-neous values (input values) or rms values(calculated values every 10 ms) are used.The maximum period of a disturbancerecording depends on the memory andsystem frequency. Within the buffer sev-eral disturbance records (up to 8) can bestored consecutively. The number is de-pendent on the parameterization and na-ture of the fault event data record.The possibility to set a pre– and post trig-ger time and the triggering event (distur-bance recording start with activation ortrip) permits flexible adaptation to the dif-fering requirements.The disturbance record data can either betransferred to the SINAUT LSA stationcontrol or to a PC, and evaluated theredepending on the user preference.

Trip matrix/trip circuits

The unit is equipped with five trip/com-mand relays. The described protectionfunctions can be arbitrarily allocated tothese relays.In addition, each protection function canbe set to ”OFF” or ”ON” via the operatorpanel. A third ”BLOCKED” position per-mits commissioning of the unit with thelocal indications and the indication (alarm)relay circuits, but without tripping of thecircuit–breakers.With the many parameterizing possibili-ties provided, testing of and alternationsto the circuit–breaker operation can beperformed during commissioning, as wellas during normal operation without theneed for rewiring.

Non–volatile storage of operationalrecords

The unit supplies detailed data for theanalysis of disturbances as well as forchecking of states during operation. Allsubsequently listed indication memoriesare safeguarded against supply voltagefailure. Real–time clock

A standardized, battery–buffered clockis provided, it is synchronized viabinary input or the system interface.All events are recorded with a dateand time tag.

Disturbance event indicationsThe indications of the last 3 distur-bances are always accessible.

Operation indicationsAll indications which do not directlybelong to a disturbance, are stored inthe operation indication buffer.

Assignable indication (alarm) relays,LEDs and binary inputs

For user–specific output and display ofindications, indication (alarm) relays andLEDs can be freely assigned. The stor-able LED displays are secured againstsupply voltage failure.All binary inputs are similarly freely as-signable. It is thus possible to assign abinary input to several logical inputs.




Technical data

Input circuits Rated current NRated voltage VN, can be parameterizedRated frequency fN’, can be parameterizedThermal overload capability

in voltage path, continuousin current path, continuous

1 s10 s

Power consumptionin voltage path at VN = 100 Vin current path at N = 1 A

at N = 5 A

1 or 5 A100 to 125 V AC50/60 Hz

140 V AC4 x N100 x N20 x N

< 0.3 VA< 0.1 VA< 0.5 VA

Voltage supply

via integrated DC/DC converterRated auxiliary voltage Vaux

Permissible tolerance at rated auxiliary voltagePower consumption

24, 48 V DC or60, 110, 125 V DC or220, 250 V DC–20 to +15 %max. 16 W

Setting ranges

Impedance protection

Starting:Current >Reset ratioUndervoltage seal–in V <Seal–in time t

Measurement:Resistance (R1 R1B)

0.2 to 4 x /N0.955 to 110 V0 to 32 s

0.05 to 65 ΩResistance (R1, R1B)Reactance (X1, X1B)

Times:Delay times t1, t1BReset delay trMinimum response time

0.05 to 65 Ω0.05 to 130 Ω

0 to 32 s0 to 32 sapprox. 80 ms

Out–of–step protection Starting:Positive sequence current 1 >Negative sequence current 2 >

Power swing polygonImpedances Za to ZdAngle of inclination P

Number of admissible swingsCharacteristic 1 N1Characteristic 2 N2

Times:Start holding time tHHolding time of out–of–step indication tMReset delay tr

0.2 to 4 x /N0.05 to 1 x /N

0.05 to 130 Ω60 to 90

1 to 41 to 8

0.1 to 32 s0.02 to 0.15 s0.05 to 32 s

Unbalance load protection Warning stage 2 >Max. continuous admissible unbalanced load t1Tripping stage 2 Tripping time t2, reset delay time trReset ratioMinimum response timeThermal replica

Time constant Warning stage

3 to 30 % of 2/N0 to 32 s10 to 80 % of 2/N0 to 32 s0.9580 ms

100 to 2500 smax. 70 to 99 % of tripping stage

Reverse power protection Reverse power –P >Delay times t1, t2 (without/with emergency tripping)Reset delay trReset ratioMinimum response time

0.5 to 30 % of SN0 to 32 s0 to 32 sapprox. 0.6 350 ms

Earth–fault protection Displacement voltage VE >Delay time t, reset delay time trReset ratio VE or EMinimum response time

5 to 120 V AC0 to 32 s0.7 or 0.95100 ms

Pick–up tolerances under ratedconditions

Current valuesVoltage valuesImpedance valuesActive power valuesTime values

3 % of setting value 3 % of setting value 3 % of setting value 5 % of setting value or 0.2 % off SN 10 ms




Technical data (continued)

On–load measurement Display of valuesfor currentfor voltagefor frequencyfor active powerfor reactive powerfor load anglefor load anglefor resistancefor reactancefor inverse current

L1, L2, L3, posVL1, VL2, VL3, 3V0, VposFreq.P/SNQ/SN

p.f.PHIRX2, 2th.

Fault recording Instantaneous values (approx. every 1.67 ms at 50 Hz)RMS values (approx. every 10 ms at 50 Hz)

L1, L2, L3, vL1, vL2, vL3, 3v0pos, Vpos, PHI, 2, R, X, P/SN, Q/SN

Contacts Potential–free trip/command contactsSwitching capacity make

breakPermissible current continuous

0.5 sSwitching voltageIndication contactsSwitching capacity make/breakPermissible currentSwitching voltage

3 x 2 NO, 2 x 1 NO (total 5 trip relays)1000 W/VA30 W/VA5 A30 A250 A DC13 (see Fig. 5)20 W/VA1 A250 V DC

Displays, inputs LED displays on unit frontBinary inputs for 24 to 250 V DC operating voltageCurrent consumption independent of voltage range

168approx. 2.5 mA

Construction For panel surface mountingWeight approx.

For panel flush mounting/cubicle mountingWeight approx.

Protection class to EN 60 529

in housing 7XP20 40–111.5 kgin housing 7XP20 40–210 kgIP 51

Standards DIN VDE 0435, part 303 and IEC 255–5 or IEC 255–6

Insulation tests High voltage test

Impulse voltage test

2 kV (rms), 50 Hz; 1 min or alternatively2.8 kV DC; 1 min5 kV (peak); 1.2/50 s; 0.5 J;3 positive and 3 negative shots at intervals of5s

Disturbance tests High frequency test(1 MHz test)IEC 255–22–1, class IIIElectrostatic discharges(ESD test)IEC 255–22–2, class IIIElectromagnetic fields(Radiated electr. magn. field test)IEC 255–222–3 (report), class IIIHigh–speed, transient disturbances(Fast transient test)IEC 41B (CO) 53 (draft), class III

2.5 kV (peak); 1 MHz; = 15 s;400 shots per s; duration 2 s

8 kV (peak); 5/30 ns;10 positive discharges

Frequency 27 MHz to 500 MHz; 10 V/m

2 kV (peak); 5/50 ns; 5 kHz;4 mJ per pulse; 1 min per polarity

Degree of radio interference DIN VDE 0871, limit value class B

Climatic conditions Permissible ambient temperature during serviceduring storageduring transport

Humidity class

–5 to +55 C–25 to +55 C–25 to +70 CAnnual average 75% relative humidity;on 30 days/year up to 95% relative humidity;condensation not permissible

Mechanical stress

DIN 40 046Permissible mechanical stress during service

during transport

10 to 60 Hz: 0.035 mm amplitude60 to 500 Hz: 0.5 g acceleration5 to 8 Hz: 7.5 mm amplitude8 to 500 Hz: 2 acceleration




Selection and ordering data

Order No.7UM516 generator protection relay 7UM516 – A 0 1 – 0 A 0

Rated current at 50 to 60 Hz, 100 to 125 V AC1 A5 A

15

Rated auxiliary voltage24, 48 V DC60, 110, 125 V DC220, 250 V DC

245

Mechanical designfor panel flush mounting or cubicle mountingfor surface mountingfor panel flush mounting or cubicle mounting, without glass cover

CDE

Serial interfacedecoupled, wire–connected (V24)integrated fibre–optic connection

BC





Fig. 5Connection diagram for the 7UM516

or

Ind.

out

–of–

step

cl.

1

Trip

out

–of–

step

(cl.

1, c

l. 2)

Trip

impe

danc

e pr

otec

tion

(Z1)

Grou

p al

arm

(act

iv. L

1, L

2, L

3)

Anti–

hunt

dev

ice

impe

danc

e pr

otec

tion

Trip

reve

rse

pow

er l–

Pr l

with

SS

Trip

unb

alan

ced

load

(

)

War

ning

sta

ge u

nbal

ance

d lo

ad (

)

Trip

sta

tor e

arth

–fal

ut (

)

Trip

cou

plin

g

Ind.

out

–of–

step

cl.2

Trip

reve

rse

pow

er l

L+ (M

2)

L+ (M

1)In

tern

al fa

ilure

TxD

Trip

com

man

d 1

Trip

com

man

d 2

Trip

com

man

d 3

Trip

com

man

d 4

Trip

com

man

d 5

Optio

nal V

.24

FO c

onne

ctio

n

RL

Exte

rnal

sig

nal 2

LED

Rese

t

Rese

t the

rmal

imag

e

Bloc

k I–

Pr I

>

Emer

genc

y tri

p va

lve

cont

act

Volta

ge tr

ansf

orm

er m

cb

Activ

atio

n ov

erre

ach

stag

e

Exte

rnal

sig

nal 1

Exci

tatio

nsy

stem

I N I L1

I L2

I L3

L+

n

e

L3L2

L1

GI 2

th.

I 2

I 2I 2

th.

V0

Unit

trans

form

er

65 64 63 68 67 66 71 70 69 86 85 84 87 88 89 7491 92 94 95 96 43 44 45 46 47 489390

7B1

8B1

6B1

7B2

8B2

6B2

7B3

8B3

6B3

7B4

8B4

6B4

3D1

4D1

3D2

3D3

4D3

4D4

3C1

4C1

3C2

4C2

3C3

4C3

3C4

4C4

3D4

4D2

19 18 17

6A3

6A1

6A2

99 100

75 72 97 98 73 20 22 23 21 24 25 49 50 76 77

5B1

5B3

5B4

5B2

5A1

5A3

5A4

5A2

6D1

6D3

6D4

6D2

5D1

5D2

5D3

5D4

4A3

4A4

L+ L– L+ MT

L– L+ L– L+ L+

Vers

ion

for f

lush

mou

ntin

g/cu

bicl

e m

ount

ing

Trip

/com

man

dre

lay

5

Alar

m re

lay

13

Trip

/com

man

dre

lay

1

Trip

/com

man

dre

lay

2

Trip

/com

man

dre

lay

3

Trip

/com

man

dre

lay

4

Alar

m re

lay

1

Alar

m re

lay

2

Alar

m re

lay

3

Alar

m re

lay

4

Alar

m re

lay

5

Alar

m re

lay

6

Alar

m re

lay

7

Alar

m re

lay

8

Alar

m re

lay

9

Alar

m re

lay

10

Alar

m re

lay

11

Alar

m re

lay

12

Bina

ryin

put 2

Bina

ryin

put 1

Bina

ryin

put 3

Bina

ryin

put 4

Bina

ryin

put 5

Bina

ryin

put 6

Bina

ryin

put 7

Bina

ryin

put 8 V.

24 in

terfa

ce, 2

kV

isol

ated

Coup

ling

to c

entra

l uni

t

Fibr

e op

tic in

terfa

ceCo

uplin

g to

cen

tral u

nit

L+ L–

4B1

4B2

L–

4A1

4A2

RxD

15 16 51 52 2683828180797862616059585756

1A1

555453

1A2

7D3

7D4

7D1

7D2

8D3

8D4

8D1

8D2

7A3

7A4

7A1

7A2

8A3

8A4

8A1

8A2

3B1

2B1

3B2

2B2

3B3

2B3

2C2

2C4

3A1

3A2

2A1

2A2

3 79 13 10 14 11 31 39 40 1 5 2 6

VL3

VL2

VL1

I NI L1

I L2

I L3

Vers

ion

for p

anel

sur

face

mou

ntin

g

I 2

Z1Ü

Pow

er s

uppl

y

MR

VN V

03

7UM

516

(Uni

t mal

func

tion

alar

m)



Dimension drawings in mm

Fig. 67UM516 with housing 7XP2040–2 (for panel flush mounting or cubicle mounting)

Front view Side view Panel cutout

206.5

180

221

7.3

13.2

255.

8

245

266

231.5

30 29.5

1.5

5.4

225

220

244

172

10

Fibre opticinterface

Diam. 5 or M4

Diam. 6

Fig. 77UM516 with housing 7XP2040–1 (for panel surface mounting)

Front view Side view

260

27 29.526

6

71Z

280

344

234

219

detail Z:fibre opticinterface

126

1.539

40

Cutout 20 x 60 (without paint)

10051 75

5025

76

7.5

. . . . .. . . . .

. . . . .. . . . .



Conditions of Sale and Delivery

Subject to theGeneral Conditions of Supply and Deliveryfor Products and Services of theElectrical and Electronic Industryand to any other conditions agreed uponwith the recipients of catalogs.

The technical data, dimensions and weights are subject to change unlessotherwise stated on the individual pagesof this catalog.

The illustrations are for reference only.

We reserve the right to adjust the pricesand shall charge the price applying onthe date of delivery.

Export Regulations

In accordance with present German andUS export regulations export licences (da-ted 03.95) are not required for the prod-ucts listed in this catalog.Export and re–export are therefore

permissible without the approval of therelevant authorities except where currentGerman export regulations contain coun-try–specific restrictions.

Subject to change.Relevant are the criteria stated in the delivery note and in the invoice.An export licence may be required due to country–specific application of theproduct.

Trademarks

All product designations used are trade-marks or product names of Siemens AGor of suppliers.

Dimensions

All dimensions in this catalog are given inmm

Responsible for

Technical contents: Norbert Schuster,Siemens AG, EV S T11, Nürnberg

General editing: Claudia Kühn–Sutiono,Siemens AG, EV MK 2, Erlangen

Conditions of Sale and Delivery Export Regulations Trademarks Dimensions

A 9.91 a


Siemens LSA 2.5.5 . April 199510Siemens Aktiengesellschaft

BereichEnergieübertragung und -verteilungGeschäftsgebietZähler, Sekundär- und NetzleittechnikP. O. Box 48 06D-90026 Nürnberg

Order No.: E50001-K5752–A151-A1–7600Printed in the Federal Republic of GermanyKG K 0495 3.0 SC 10 En

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Generator Protection - Automation-Berlin