REYROLLE 1 Introduction • Micro TAPP voltage control and monitor is a numeric system based • Widely used as Super TAPP relay • Operational control of Tap changing transformers and protection against abnormal voltage • Full supervision and self monitoring of the internal relay functions • User friendly access to the relay setting, displays ontions and fault data • A Reydisp evolution software is used to set and commission the relay.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
REYROLLE1
Introduction
• Micro TAPP voltage control and monitor is a numeric system based
• Widely used as Super TAPP relay• Operational control of Tap changing transformers and
protection against abnormal voltage• Full supervision and self monitoring of the internal
relay functions• User friendly access to the relay setting, displays
ontions and fault data• A Reydisp evolution software is used to set and
commission the relay.
REYROLLE2
Power System Requirements• Power supply quantity in all voltage level from transmission and
distribution networks• Automatic voltage control of the electrical network is done by the use
of voltage sensing relays:- On Load Tap Changers (OLTC)Micro TAPP Functionality• An analog voltage and current are connected to the measurement
inputs• Quantities are filtered out for noise• Sampled 32 x per cycle at 50 Hz system and digitised• Use 3 phase VT, one phase is used for measurement. Phase A-B for
measurement and B-C phase for measurement monitoring.• Plant input such as “tap in progress and remote “tap raise or lower”
are connected to the status inputs• Intelligent operation monitoring by BCD (Binary Coded Decimal)
REYROLLE3
• The VT input to the relay is measured against the target setting applied via the system menu
• The voltage is only used for measurement if the voltage quantity is confirmed as satisfactory by the voltage monitor
• The relay will respond to a voltage which is outside the set-point dead band and initiate a timing interval for operation of the transformer tap changing mechanism
• Where a 3 phase VT is used, each phase is monitored as a check against fuse failure
• Any abnormalities detected will inhibit the voltage raise outputs from the relay.
REYROLLE4
Current Measurement
• The measurement of transformer is used by the relay to :-
a) Calculate the group connected load and provide network Load Drop Compensation (LDC)
b) Calculate circulating reactive current
c) Provide on-line reading and historic data
REYROLLE5
• When selected to “automatic” mode:- the voltage regulating relay controls the transformer tap changer
• Voltages which are outside set voltage limits (dead bands) automatically initiate the operation of the transformer tap changer
• When selected to “manual” mode:- the voltage can be regulated via the relay manual raise/lower control switches
• The raise or lower command will only be issued after an initial time delay as set on the voltage regulating relay
• A definite time or an inversely time characteristic is selectable at Micro TAPP.
• Raise and Lower commands operate normally open relay contacts. Output contacts can be mapped to generate alarms or lockout signal
REYROLLE6
Transformers in Parallel• With traditional schemes where 2 or more
transformers are connected in parallel• The following conditions are met:-
a) The transformers are identical
b) The transformers have the same number of taps and tapping interval
c) The transformers have the same impedance
d) The transformers are always on the same tap position
e) The transformers are fed from the same primary source
REYROLLE7
• The Micro TAPP can be configured for use with Master/Follower tap change control scheme, but it is not recommended
• Each Micro TAPP can be connected to other Micro TAPP relays through a screened twisted paired cable
• The Micro TAPP Peer to Peer Communication (MPPC) system is used to transfer data between the relay at site
• If a Micro TAPP relay is de-energized, communication between other relays is not affected
REYROLLE8
Relay Settings• The Micro TAPP is designed as an integral control device • The following information is used by the relay
a) Site data:- Number of transformer forming a groupb) Transformer data:- Rating, impedance, VT and CT detailc) Tap change:- Number of steps, type, etcd) Network data:- Power factor, system voltage, group capacity, etce) Voltage control:- Basic, Band, LDC, etc
• Micro TAPP relay can be configured as ‘Transformer switch out’ and ‘Transformer switch in’
• The command can be initiated either by a SCADA signal from a PC via communications network or from hard wired lacal control switch
REYROLLE9
Control• Micro TAPP relay provides both manual and automatic control of the
tap changing system• The relay is configurable for either local control or remote control
from a control center• Electrical control of a tap change mechanism is normally exercised
from 3 point:-a) At the tap change mechanism:- A Local/Remote selector switch at the
tap changerb) At the voltage control relay panel:- Local/Remote selector on the Micro
TAPPc) At a remote site:- When Micro TAPP is set to Remote, control can be
selected and operated from a remote control center• Auto/Manual:- This switch sets the relay to automatic or manual
voltage control• When the Micro TAPP is set to “manual”, the relay will not correct
the voltage automatically
REYROLLE10
• Raise/Lower:- When the Auto/Manual is set to manual, this switch allows the tap changer to be operated either to increase the tap position or reduce the tap position
• Tap changer:- The tap changer operation is monitored for a mechanism wiring or relay fault. The following is provided
a) Tap change run awayb) Tap change incompletec) Limit of tap change ranged) Tap not achievable
• For correct operation, the following must take place:a) A control signal must be issued to initiate the processb) The tap position must change to a new positionc) The tap change mechanism must stop completely
REYROLLE11
• Fault records:- This screen enables the 10 most recent tap changer fault to be viewed. For each with date and time stamped.
• Event Records:- The event storage buffer holds 200 records with date and time stamped
• A green LED labeled ‘Relay Healthy’ is provided and will be permanently ON. If a permanent fault is detected the LED will flash continuously
• A green LED indicates that the measured voltage is normal• A red LED indicated that the measured voltage is above the relay
dead band setting. If the over-voltage monitor has detected a failure the LED will flash
• A red LED indicates that the measured voltage is below the relay dead band setting. If the under-voltage monitor has detected a failure, the LED will flash
• An amber LED indicates that the tap change mechanism is in the operating state. If the tap change monitor has detected a failure, the LED will flash
REYROLLE12
• Micro TAPP relays are housed in either Epsilon E8 or E12 case
a) E8 case (MT 101) 11 input and 5 outputb) E12 case (MT 102 or MT 101 with extra I/O) 19 input and 13 output
• Rear case an IRIG-B port is also provided for time synchronization
• 2 pairs of fiber optic ST plug connectors are available for the following ;
a) Com1 for substation SCADAb) Com2 for access by protection engineer to the relay from a laptop
computer or PC using sigma converter
• Front 25 pin RS232 port is also available• For IEC 103 protocol should operate on either com1 or com2
REYROLLE13
Power System Voltage Control
MicroTapp
REYROLLE14
BUSINESS REQUIREMENTS
• CUSTOMER
• Correct voltage levels at all times
• Continuous supply
• SUPPLIER
• Zero Maintenance
• Zero Adjustments for any operational situation
• Minimisation of system losses
REYROLLE15
OPERATIONAL PROBLEMS
• Network switching
– Switching transformers OUT of service
– Switching transformers IN to service
– Networks in parallel
• Automated control systems
• Embedded Generation
• Skill levels
• Abnormal voltages
REYROLLE16
TAP CHANGE CONTROL SYSTEMS
• MASTER - FOLLOWER– COMPLEX CONTROL SYSTEM– TRANSFORMERS & TAP CHANGERS MUST BE IDENTICAL– INCOMING VOLTAGES MUST BE THE SAME– NOT ABLE TO RUN IN PARALLEL ACROSS A NETWORK
• CHANGE-OVER SCHEMES– SHORT OUTAGE DURING CHANGE-OVER– COMPLEX CONTROL SYSTEM– INCREASED COPPER LOSSES
• CIRCULATING CURRENT– SIMPLE WIRING BUT REQUIRES CB AUXILLARY SWITCHES
– NOT ABLE TO RUN IN PARALLEL ACROSS A NETWORK• REACTIVE CIRCULATING CURRENT
– SIMPLE WIRING– PARALLEL OPERATION ACROSS A NETWORK– CAN OPERATE DISIMILAR TRANSFORMERS IN PARALLEL
REYROLLE17
‘Identical’ Transformers
Line Voltage (kV)
11
11.1
11.2
11.3
Current (A)
0
250
500
750
1000
Power Factor
0.7
0.8
0.9
1
Tap Position
1
2
3
4
5
6
Circulating Current (A)
0
20
40
60
0:00 6:00 12:00 18:00 0:00
REYROLLE18
Parallel Transformers
'High' 'Low'
‘Transformers are on the correct tap position when minimum circulating current flows between them and the system voltage is correct’
Reactive current flowbetween transformers
REYROLLE19
Reactive Current
Line Voltage
Load
Export circulatingcurrent
Measured voltage
REYROLLE20
MicroTAPP - True Circulating Current
Voltage
G roup Load
T 1 current
C irculating
current
T 2 current
T 1
T 2
REYROLLE21
Reactive Circulating Current
T arget PF
Voltage
G roup Load
T 1 current
C irculating
current
T 2 current
T 1
REYROLLE22
7 8 9 9 7 7 7 6
Tx A
Tap > Tap >
Tx B
A BA B CC
Conventional AVR – Why Independent Auto Results in Drifts
REYROLLE23
7 8 8 7 7 7 8 8
Tx A
Tap > Tap >
Tx B
A
B
A B
CC
Microtapp – Independent Auto, but No Drifts
REYROLLE24
Features
REYROLLE25
Initial Delay to tap Change - DMT
O perateT im e
RelayDeadband
80% Volts
Initia lDelay
Band+2%
REYROLLE26
Tap Change - Overcurrent Blocking
Voltage
T ransform erLoad
Full Load
Norm al O peration
Block Raise Volts
B lock Low er Vo lts
T otal b locking
80% Volts
Low er Band
Upper BandBlocks operationfor excessive LOADbut allowsoperation to reduceCIRCULATINGcurrent
REYROLLE27
Tap Change - Normal operation
time
Raise / Lower Reclaim pulse time
Raise / Lower Reclaim pulse time
Normal Raise / Lower command
In progress logic
Intelligent Tap Positionindicator
Lock out
IP Indication
REYROLLE28
Tap Change - Runaway condition
time
Raise / Lower Reclaim pulse time
NOTE: Timed lockout will occur if second TPI is NOT detected
Normal Raise / Lower command
In progress
Intelligent Tap Positionindicator
Lock out
Timed tap change lockout
REYROLLE29
Hardware
REYROLLE30
MicroTAPP - E8 Case General View
RELAY HEALTHY
LO W
NO RM AL
HIG H
T AP INPRO G RESS
TRANSFO RM ER 1
10.9 07kV -1h
LO CAL AUTO
TAPCO NTRO L
M ENU TEST LEDS
T AP
REYROLLE31
MicroTAPP - Rear View Connections
IR IG B
T X1
RX1
T X2
RX2
28 W AY CO NNECT O RBLO CKS
REAL T IM E CLO CKINPUT
CO M M UNICAT IO NSPO RT 1
CO M M UNICAT IO NSPO RT 2
REYROLLE32
MicroTAPP - Operational Display
TRANSFO RM ER 1
10.9 07kV -1h
LO CAL AUTO
TAPCO NTRO L
M ENU TEST LEDS
T AP
TRANSFO RM ER 1
10.9 07kV
LO CAL AUTO
TAPCO NTRO L
M ENU TEST LEDS
T AP
REYROLLE33
MicroTAPP - Control Level Display
LO W ER RAISE LO CAL REM O TE
EXITAUTO /
M ANUALM O VE ->
M ANUAL/AUTO
TAP 711.2kV
LO W ER RAISE LO CAL REM O TE
LO W ERTAP
RAISETAP
M O VE ->
M ANUAL/AUTO
TAP 711.2kV
REYROLLE34
MicroTAPP - Configuration
TRANSFO RM ER 1
UP DO W N SELECT
SETTING S M O DE
INSTRUM ENTS M O DE
FAULT DATA M O DE
20/09/1999 16:08:40
CANCEL
TRANSFORMER 1
EXIT NEXT CANCEL
20/09/1999 16:08:40
11.3 18.0 0.97Line (kV) Load (MVA) pf lag
REYROLLE35
Settings
REYROLLE36
24 hour Historical Records
REYROLLE37
Event Listing
REYROLLE38
VT and CT Connections
REYROLLE39
Connection to Tap Position Transmitter
Resistor Chain Type BCD Type
REYROLLE40
MPPC Screend twistedpair cable
MPPC line terminatorlink
MPPC line terminatorlink
MPPC screen earthing ata single point
MPPC Inter-MicroTAPP connections
MicroTAPP 1
B1B3 B5
B7
IntermediateMicroTAPP
B1B3 B5
B7
MicroTAPP N
B1 B3B5
B7
MPPC Link Connection
REYROLLE41
REYROLLE42
Communications
Communications to IEC60870-5-103 protocol
Fibre optic with ST connectors
May be connected in a loop with 254 relays
Fibre optic hub available for star configuration
REYROLLE43
Ring Connected Data Comms
F.O Cables
Sigma3
TXRX
RX
RXRXRX
TX
TX TX TX
RS232
PCs to be equipped with Reydisp software
Up to 254 relays can be connected in single loop
Each relay to have unique address LocalPC
RemotePC
REYROLLE44
Star Connected Data Comms
• Star connected data comms• Increased Security
• Sigma 1 F.O. Hub
F.O Cables
Sigma1
LocalPC
RemotePC
REYROLLE45
MicroTAPP - A complete system
Basic Voltage Control Relay
Monitor Relay
Local / Supervisory Control Switching
Communications
Tap Position Inputs
In service over 14 yearsSuperTAPP >6000MicroTAPP >400