ABB AVR PPT

8/2/2019 ABB AVR PPT

1/45

UNITROLUNITROL 50005000


2/45

Refresher:Refresher:

Excitation SystemsExcitation Systems


3/45

UNITROL5000

AVR

Automatic VoltageRegulator

Excitation Transformer

Thyristor

ConverterCrowbar

Field Breaker

Excitation System Main ComponentsExcitation System Main Components


4/45

UNITROL5000

Providing variable DC current with

short time overload capability Controlling terminal voltage with

suitable accuracy

Ensure stable operation withnetwork and / or other machines

Keep machine within permissibleoperating range

Contribution to transient stabilitysubsequent to a fault.

Communicate with the power plantcontrol system

AVR

Excitation System Duties


5/45

UNITROL5000

Max. field current limiterMax. field current limiter

Min. field current limiterMin. field current limiter

Stator current limiterStator current limiter

Under excitation P,Q limiterUnder excitation P,Q limiter

P

+Q-Q 1/Xd

Power Chart with Opreation Limits


6/45

UNITROL5000 Excitation Transformer

Galvanic insulation between power

source and rotor winding

Limitation of DC short circuit current

Adaptation of supply voltage to reach the

required ceiling voltage

Air cooled or oil immersed


7/45

UNITROL5000 Thyristor Converter

Rectification of AC voltage

Fast control of DC current

Inversion of DC voltage

Short-time overcurrent capability

Withstand certain overvoltages onAC side

Limitation of commutation

overvoltages


8/45

UNITROL5000 Field Discharge Circuits

Field Breaker on AC-side of the converter

Opening of field circuit under fault conditions

Fast absorption of field energy

Field overvoltage protection

Allow machine to slip


9/45

UNITROL5000 AVR Automatic Voltage Regulator

Control terminal voltage on preset value with required accuracy

Ensure stable operation with network and / or other machines

Keep machine within permissible operating range

Generate thyristor triggering pulses even under possible fault conditions

Communicate with the power plant control system


10/45

UNITROL5000 Basic Characteristics

Excitation Current up to 10000 amps

Input frequency range from 16 Hz to 400 Hz

Adaptable to different redundancy requirements for controls and converters

State of the art man machine interface

Compatibility with most applied power plant control systems

Remote diagnostics

Comfortable commissioning tools


11/45

UNITROL5000 Operational Application


12/45

UNITROL5000

RangeofA

pplication

Generator Power/Excitation current

Excitation withrotating machines

Static Excitation Systems

UNITROL5000

UNITROLF

UN 1000

15A 500 A >10000 AIfn

Product RangeProduct RangeUNITROL


13/45

UNITROL5000

UNITROL 5000UNITROL 5000 UNITROLF

REDUNDANCY- Control Current control back up or Full redundancy

full redundancy

- converter Twin or N-1 Twin

HARDWARE- No. of digital I/Os >32 32- Current measurement 3-phase 1-phase

BUS COMMUNICATION AF100 30 words AF100 6 Words

CONVERTOR SUPPLY 16400 Hz (unlim. Current) DC 25 A16400 Hz max

300 A

Delimitation Against UNF


14/45

UNITROL5000

UNITROL 5000UNITROL 5000 UNITROL

CONTROL FUNCTIONS Adaptive Power SystenStabilizer

CONVERTER Negative excitation current

(4 quadrant)Automatic equalizing ofbridge current

FAULT HANDLING Real time stamp sequence of faults

Delimitation Against UNF


15/45

Main Standard Software FunctionsMain Standard Software Functions


16/45

UNITROL5000

Me

asuring

Protection

Monitoring

AVR + FCR

Logic Control

Fieldbreaker

Field flashingField suppression

AVR 1AVR 2

ConverterControl

CONVERTER 1

CONVERTER 2

CONVERTER 3

AVR = Autom. Voltage Reg.

FCR = Field Current Reg.

Systems Overview


17/45

UNITROL5000 Standard Program Functions

CLOSEDCLOSED--LOOP CONTROLLOOP CONTROL (AVR, Limiters, Other controllers) Voltage regulator with adjustable PID filter circuit Soft-start (gradual voltage increase)

Reactive and active current droop Individually adjustable limiters

- overexcited (max. field current, stator current)

- underexcited (-Q = f (P) * U2, stator current, min. field current)

- Volt per Hertz

Superimposed controllers- Power Factor

- MVAr

- Soft-stop (MVAr unload)

Power System Stabilizer (add. Hardware required)

Field current regulator with adjustable PI filter Follow-up control between AUTO / MAN mode

A

UTOMATIC

MANUAL

IARV / UNF10 E

CHIND / 612


18/45

UNITROL5000

Max. field current limiterMax. field current limiter

Min. field current limiterMin. field current limiterStator current limiterStator current limiter

Under excitation P,Q limiterUnder excitation P,Q limiter

P

+Q-Q 1/Xd

Power Chart with Operation Limits


19/45

UNITROL5000

+P[MW]

+Q[MVAR]-Q

Q = 0.2 p.u

+P [MW]

+Q [MVAR]

-P

-Q

Cos = 0.8

a) POWER FACTOR Control b) REACTIVE POWER Control

Superimposed RegulatorsSuperimposed Regulators


20/45

UNITROL5000 Standard Program Functions

MONITORING AND PROTECTIONMONITORING AND PROTECTION

Thyristor conduction monitoring Thyristor heatsink temperature

DC short-circuit Field flashing time Loss of actual value (PT failure)

Overcurrent Volts per Hertz Loss of excitation Rotor temperature

Rotating diode failure (add. hardware required)

IARV / UNF11 E

CHIND / 612


21/45

UNITROL5000

Rotor thermal overload stage 1

Rotor over temperature stage 1

Loss of p.t.

SW supervision per channelHW supervision per channelsupply monitoring

HW /SW

monitoring

Thyristormonitoring

Air flow

monitoring

Monitoring Concept

(use of redundancy)


22/45

UNITROL5000

Overflux V/HzOver temperatrure

Over load

Rotor earth faultRotor short circuit

Rotor thermal overload stage 2Rotor over Temperature stage 2Rotor overvoltage

SW supervisionHW supervision

internal supply

internal shortcircuit

converter overload

Protection Concept (shut down)


23/45

UNITROL5000

Current versus time characteristic ofconverter and settings of protectionfunctions for a 48 MVA generator

1 p.u. = 1'315 A

0.1 0.2 10

1

1.6

2

3

t (s)

I(p.u.)

f

n bridges

(n = 3)

n-1 bridges(n = 2)

Change over

to manual

Rotor

Iflimiter

Trip

Induced field current

3ph SC gen. terminals

Induced field current3ph SC HV side block transf.

Overcurrent Capability and

Protection Setting


24/45

UNITROL5000

+

_

+

_

AVR Setpoint-V/Hz limiter- Soft start- IQ Compensation- IP Compensation

Underexcit. limiter-Q=F(P,U,UG)-Stator current lead

-Min. field current

Overexcit. limiter-Max field current-Stator current lag

Power SystemStabilizer PSS

Man setpoint

MeasuringandA/D

conversion

Min.

/ma

x.valuepriority

PID

PI

To pulsegeneration

UG, IG, If

UG, IG

UG

UG, IG, If

UG, IG

If

AVRs Main Functions


25/45

UNITROL5000

Low

value

gate

PID

PSS

High

value

gate

UGAVR set point

Parameter set 2

IG OEL

IG UEL

P(Q) UEL

Parameter set 3Ie max lim OEL

Ie min lim UEL

Under excitation

limiter

UEL

Over excitation

limiter

OEL

Parameter set 1 AVR

Parameter set

1,2,3

Intervention in the AVR

OEL and UEL Limiters


26/45

UNITROL5000

t

UGIf

Field FlashingReference value ramp up

Normal operation

Intervention in the AVRs

Set Point Soft Start

I t ti i th AVR S t P i t


27/45

UNITROL5000

+ Q- Q

UG

Uref

droop

compensation

Reactive Power Droop+ P

UG

Uref

droop

compensation

Active Power Droop

Intervention in the AVRs Set Point

Reactive and Active Power Droop

I t ti i th AVR


28/45

UNITROL5000

f

UG set point

UG nominal

fnominal

UG min set point

UG max setpoint

Setting range V/Hz

Allowed range of operation

Intervention in the AVRs

Set Point V/Hz-Limiter


29/45

UNITROL5000

Power factor control

MVAr control

MVAr unload control

MUB

QBUS

QGEN

PFGEN

PFBUS

Q controlDischarge

P.F control

BUS 1)

Generator

Power

factor

Reactive

Power

Dis-charge

(0)

set point

AVRset point

1) mainly used in

industrial plants

Super-Imposed Controllers


30/45

UNITROL5000

Uf [p.u.]

Generatorvoltage [p.u.]

GeneratorReactivePower [p.u.]

1

1+sTR

HV

Gate

LV

Gate 1+sTB2

1+sTC2

UPKR

TBTC

+ 11

UP

KR

TB

TC

11

1+sTB1

1+sTC1

UP

KR

+

UP

KR

KR1

1+sTs

Up+ UTKc If

Up- UT

from under-excitation

Limiters UEL

from over-excitation

Limiters OEL

UT -

UT setpoint

[p.u.]

+

1

1+sTR

1

1+sTR

KIR

KIA

QT

PT

+

+

+

UST

Stabilizing

signal from PSS

GeneratorActivePower [p.u.]

+

+ Parameter Description Unit RangeTR Measuring filter time constant s 0.020

Ts Gate control unit and converter time constant s 0.004

KIR Reactive power compensation factor p.u. -0.20...+0.20

KIA active power compensation factor p.u. -0.20...+0.20

KR Steady state gain p.u. 10...1000

Kc Voltage drop due to commutation p.u. Acc. Transf.

TB1 Controller first lag time constant s TB1TB2

TB2 Controller second lag time constant s 0


31/45

UNITROL5000

s.TW3

1 + s.TW3

Ks2

1 + s.T7

s.TW4

1 + s.TW4

Ks3

V2

UST

+

s.TW1

1 + s.TW1

s.TW2

1 + s.TW2

( )

( )

1 8

1 9

+ +

s T

s T M

N ++

-

1+s.T1

1+s.T2Ks1

1+s.T3

1+s.T4

USTmax USTmax

USTmin USTmin

V1

Parameter Description Unit Range

TW1,TW2 Measuring filter time constant s 0.1...30

TW3,TW4 Gate control unit and converter timeconstant

s 0.1...30

Ks1 PSS gain factor p.u. 0.1...50

Ks2 Compensation factor for calculationof integral of electric power p.u. 0.01...5

Ks3 Signal matching factor p.u. 0.01...5

T1,T3 Lead time constants of conditioningnetwork

s 0.00...2.50

T2,T4 Lag time constants of conditioningnetwork

s 0.00..2.50

Parameter Description Unit Range

T7 Time constant for integral of electricpower calculation

s 3...30

T8 Ramp tracking filter time constant s 0.00...2.50

T9 Ramp tracking filter time constant s 0.00...2.50

M Ramp tracking filter degree - 2...5

N Ramp tracking filter degree - 1...4

USTmax Upper limit of stabilizing signal p.u. 0.000...3.277

USTmin Lower limit for stabilizing signal p.u -0.000...-3.277

Transfer Function

Acc. to IEEE PSS 2A


32/45

RedundancityRedundancity conceptconcept


33/45

UNITROL5000

IARV / SES38 E

CHIND / 805

Redundancy

Every converter bridge is supplied with its own ventilator and pulse

amplifier.

(n-1) Redundancy Several converter bridges operating in parallel at the same

time (3 x 50 %, 4 x 33.3 %, etc.)

In case of failure of one bridge, this one is blocked.Operation continues without restrictions.

(1+1) Redundancy (Twin)

Two bridges: one in operation, the other blocked (2 x 100 %) In case of failure of the active bridge, there is a switch-over

to the standby bridge.


34/45

UNITROL5000

AVR

FCR

UGIG

IF

AVR = Automatic Voltage Regulator

FCR = Field Current Regulator

Single Channel AVRSingle Channel AVR

Automatic channel with change over to manual control

Type S5E


35/45

UNITROL5000

AVR

FCR

IF

AVR = Automatic Voltage RegulatorFCR = Field Current Regulator

BFCR = Backup Field Regulator

BFCR

Block

Backup Regulator follows themain control and takes overautomatically in case of failureof the main control but not viceversa

Backup Regulator follows themain control and takes over

automatically in case of failureof the main control but not viceversa

Single Channel and back up FCR

Type D5E

UGIG

IF


36/45

UNITROL5000

AVR

FCR

Block

IF BFCR

Block

AVR = Automatic Voltage RegulatorFCR = Field Current RegulatorBFCR = Backup Field Regulator


With Redundant Twin Converters(cold standby, 100% redundancity)

Type D5T

UGIG

IF


37/45

UNITROL5000

AVR

FCR

1

2

n

IF BFCR

Block

AVR = Automatic Voltage RegulatorFCR = Field Current RegulatorBFCR = Backup Field Regulator


With redundant n-1 Converters(Redundancity: 3 x 50%, 4 x 33%, 5 x 25% etc )

Type D5S

UGIG

IF

Dynamic Current Distribution among


38/45

UNITROL5000

t

t

t

Current equalizing line

Thyristor firing pulses from AVR

+

-

1 2 n

Dynamic Current Distribution among

Parallel Converters


39/45

UNITROL5000



AVR

FCR

AVR

FCR

Block

Two Channel Control

With Single Converter

Type A5E

UGIG

IF

UGIG

IF


40/45

UNITROL5000

Regulation

Logic Control

Regulation

Monitoring

Protection

Logic Control

Voltage regulator (AUTO)

Field current regulator (MAN)

Power System Stabilizer

Limiter functionsOverriding controllers (P.F., VAr)

Actual voltage value (P.F. failure)

Actual field current value

CPU

Rotor temperature

Field overcurrentV/Hz

Rotating diodes

Actual valuesTrip signals

Status of systemFollow-up

Actual voltage value

Actual field current value

CPU

Field overcurrent

V/Hz

Rotating diodes

Monitoring

Protection

STAND BY OPERATING

Redundancy Concept of A5..Types


41/45

UNITROL5000



AVR

FCR

AVR

FCR

BlockBlock

Two Channel control

Type A5T

With Redundant Twin Converters(cold standby, 100% redundancity)

UGIG

IF

UGIG

IF


42/45

UNITROL5000



AVR

FCR

1

2

n

AVR

FCR

Block

Two Channel control

With redundant n-1 Converters(Redundancity: 3 x 50%, 4 x 33%, 5 x 25% etc )

Type A5S

UGIG

IF

UGIG

IF


43/45

UNITROL5000

BFCRIF

IF BFCR

AVR

FCR

1

2

n

AVR

FCR

Two Channel control with Back up FCR

Type Q5S With redundant n-1 Converters(Redundancity: 3 x 50%, 4 x 33%, 5 x 25% etc )

UGIG

IF

UGIG

IF

UNITROL 5000 S ti l f R d d


44/45

UNITROL5000

TRIP

Functionality AVRFull Prot.

Full Monit

Full Control

FCRFull Prot.

Full Monit

Full Control

BFCRBack up

Prot.

Minimum

Control

AVRFull Prot.

Full Monit

Full Control

FCRFull Prot.

Full Monit

Full Control

BFCRBack up

Prot.

Minimum

Control

Possible

Failure

Failure

in AVR

Failure

in Hardware

Failure in

back upcontrol

Failure

in AVR

Failure in

Hardware

Failure in

back upcontrol

D5..

A5..

A5.. with BFCR

CHANNEL 1 CHANNEL 2

Sequentional use of Redundancy

UNITROL 5000


45/45

UNITROL5000

The reference values of all controllers that are on standby orswitched off are always adjusted so that bumpless change over isassured.

Automatic Voltage Regulator AVR set point

Field Current Regulator FCR set point

Back up Field Current Regulator BFCR set point

Superimposed Q-control set point (optional)

Superimposed Power Factor control set point (optional)

Follow up Control

Documents

ABB AVR PPT