Universal Differential relay 7SD610

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Universal Differential relay 7SD610
87 Universal differential relay - For line /
cables- with transformers in the protection
zone With secure digital communication - Fibre
optic cables- Communication networks - Digital
telefon network / telefon cables 7SD610
In preparation
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Protection and communication come togetherThree
benefits of the 7SD610

• Differential protection for the universal
  use with easy to handle settings Two line
  terminals, Less CT-requirements Handles
  transformers and compensation coils within
  the protection zone Tripping time less than
  one period
• Additional functions Backup (parallel
  running) or emergency O/C - function (3 stages)
  Breaker failure protection, Overload
  protection, Switch on to fault feature, 4
  fast remote signals, Intertrip function
  Supervision of the communication link, Bus-wire
  supervision
• Direct and modular connection to fibre optic
  and digital communication networks

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Application - Fibre optic connection
Direct connection with fibre optic (FO) cables-
Offers high speed tripping (16 ms)- Flexible
plug in modules for different fibre typ or
distance
Distance FO-cable Connector
820 nm, 1,5 km
Multimode62,5/125 um
STSTSTFC
820 nm, 3 km
FO
1300 nm, 10 km
Monomode9/125 um
1300 nm, 35 km
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Application - Digital communication network
Connection via a communication system with
multiplexers - Automatic delay time measurement
(adaptive correction from 0 ms - 30 ms)-
Immediate detection of switch-over conditions of
communication routes- Communication addresses,
Synchonous electrical interface X.21 (64/128/512
kBit/s) or G703.1 (64 kBit/s)

Communicationconverter
820 nm, 1,5 km
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Application - Leased telefon line
Leased telefon line (standby or dial-up) - 2 wire
telefon cable (max. 8 km)

Twisted telefon pair max. 8 km (5 miles)
E
O
820 nm, 1,5 km
Communicationconverter
5 kV insulationintegrated
In test
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Applications - Line or cable with different CT -
ratios
4005, 10P10, 10VA, kAlf 59, k 50
6001, 5P20, 20 VA, kAlf 130, k 33,3
VT optionNot requiredfor diff. function
20 kA
___ IN,CT
IK,max
k
87L50/5150 BF49
- Mismatch of the CT ratio of 18 allowed, 1A or
5A input settable in the relay- CT datas /
errors are set in the relay and automatically
considered in the restraint current calculation-
CT-requirement kAlf for the local CT must be
greater then k (kmin 30)
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Application - Transformer and line in the
protection zone
20 MVA, 110 kV/20 kV, Yd1
10P10, 10 VA, 2001
10P10, 10 VA, 5005
1 mile
87T50/5150 BF49
tripcommand
- Settings for the transformer datas in each
relay with vector group matching, ratio
adaption and zero sequence elimination -
Differential setpoint is rated to the nominal
current of the transformer - Inrush restraint
with second harmonic included (time limit for
Crossblock) High set element for immetiate trip
(16 ms) through heavy fault currents
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Scope of functions / Hardware options
Options for the Protection Interface
Scope of functions - Fast high set element
IDiffgtgt. Current summation.- Sensitive trip
stage with vector summation IDiffgt -
Autoreclosure 1/3 pole - Communication features -
Commissioning aid - Overload protection -
Backup-/emergency overcurrent - Breaker failure
protection- Switch on to fault protection- 4
remote commands- Intertrip (also from
external)- User defined logic- Exact time
tagging
Relay Hardware
820 nm1,5 / 3 km multimode
ST- connector
- 3Iph, and IE - 4 U - 7 binary inputs - 5
trip contacts - 1 alarm contact - 1 Protection
interface - System interface (option) - Rear
DIGSI interface (option) - Time synchronisation
interface for GPS
internal
1300 nm10 kmmonomode
ST- connector
internal
1/3 19
O
1300 nm35 kmmonomode
FC- connector
internal
ElectricalX21 G703.1interface
820 nm1,5 kmST-connectors
External converter
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Modular hardware concept with Plug in modules
Plug in modules
Protection interface 1Port D
Remote line end
Synchronous N x 64kB/sec
Subst. control interface
Substation control
Communication modules
Interfacemodul 2
RS485 or RS232 Available ProtocolsIEC - standard
RS485 or FO
DIGSI 4 also for modem connectionand Browser
Interfacemodul 1
RS485 RS232
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Main board of the relay with its Communication
- Interfaces
Main processor board of the relay Sockets for
the communicationmodules
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Main protection functionFeatures of the
differential function

• Phase selective differential protection (2
  terminals). Tripping time of 16 ms with fast
  trip stage.
• Fundamental vector comparison for the sensitive
  trip stage. Detects even high resistive faults
  under full load.
• Dynamic increase of sensitive differential
  setpoint during switch-on of long cables
  (settable time)
• CT saturation detector. Increase of restraint
  current if CT-saturation is indicated by the
  measured fault currents.
• Phase selective intertrip within 20 ms (normally
  not required)
• Settable delay time for single phase faults
  (special feature for inductive compensated
  networks)
• Inrush detection with 2nd harmonic. Undelayed
  trip forheavy fault currents.
• Vector group matching and zero sequence current
  elimination included with transformer option
• Lockout function

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Adaptive differential relayingConsideration of
CT- errors and comms-errors
I1
I2
IDiff
Tripping area
I2
Restraint area
I1
IDiffgt
Max.measurementerror (e) due tolinearCT -
error
Currentsummation Max. errorsummation
IRest
IDiff I1 I2 I3
IRest IDiffgt eCT1 I1 eCT2 I2
Sync.error
Trip, if diff.current exceeds the estimated error
(restraint)
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Settings for CT - parametrer
C.t. Parameter
c.t. e.g. 5P20, 10VA
Pi PN
tolerance at ALFN
With PB Pleads Prelay (?0,1
VA)
ALFe ALFN
Pi PB
Thumb rule Ri ? 0,1...0,2 RN RN at 10 VA ?
10? gt Ri ? 2 ?
ALFe ALFN
2 VA 10 VA

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2 VA 1 VA

• Resulting Relay Parameter
• effective ALF / nominal ALF 4 (calculation as
  per above)
• IEC 44 -1 tolerance in load area up to ALFe /
  ALFN 1 with 5P, 3 with 10P c.t.s
• total error at accuracy limit nN 5 with
  class, 5P and 10 10 P

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Approximation of CT-tolerance
Basis for the restraint current calculation is
the estimated max. measurement error of the CT
IDiff
I1
Fault current tolerance

Tolerance of a real CT
Load current tolerance

ALFe / ALFN IN,c.t
I1
parameter 7SD610, 7SD52
Example 10P10, eload lt 3, eFault at k_ALFN 10
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Restaint current calculted by the relay from
the CT-datas
I1
I2
Both CTs 4001, 10P10
eLoad 5 (3 2 safety magin) eFault
10 kAlf / kAlf,N 2
IC50 A
e
10
5
I/IN,CT
1
2
Setting for I_Diffgt IDiffgt 2,5IC / IN,CT
125 A Restraint current calcuation by the relay
(adaptive)I1 I2 200 A IRest
IDiffgt 0,05206 A 0,05200A 125 A 20 A
145 A (0,36) I1 I2 600 A IRest
IDiffgt 0,1600A 0,05600A 125 A 90 A
215 A (0,53) I1 I2 1000 A IRest
IDiffgt 0,11000A 0,11000A 125 A 200 A
325 A (0,82)
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Values displayed in DIGSI 4 with 50 load
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Grafical view in a Browser screen with 50 load
Currents (amount / phasor)
Differential and restraint values
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Values displayed in DIGSI 4 with 150 load
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Grafical view in a Browser screen with 150 load
Currents (amount / phasor)
Differential and restraint values
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Values displayed in DIGSI 4 with 250 load
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Grafical view in a Browser screen with 250 load
Currents (amount / phasor)
Differential and restraint values
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To complete the 7SD610Additional functions

• 3 stage backup- or emergency O/C protection(Can
  be activated automatically if the communication
  with the remote end is gt50 ms interrupted)
• Overload function (Thermal replica with
  IOperation)
• Breaker failure protection
• User definable logic and control functions(AND,
  OR, NOT, Timer, Flip-Flop)
• 4 remote commands via binary input or logic
  inputs
• Operational values currents, voltages,
  power,delay time, differential current - remote
  end refresh 2 s
• Fault recorder with voltages, currents, binary
  traces and differential and restraint current per
  phaseFault records are exactly time synchronized
  at both line ends
• Fast monitoring functionsFast broken wire
  supervision, Current symmetry
• Switch On to Fault protection with breaker
  monitor
• Option Three pole and single pole AR (Single
  pole AR during 2pole fault without earth
  possible, adaptive AR)

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Familiar with digital communication networks
Features of the relay to relay communication

• Synchronous data transmission by HDLC- protocol
  - 32 bit CRC-checksum offers extreme high
  security
• Permanent supervision of the data transmission
• Microsecond resolution time tagging of the
  telegrams - Exact time synchonisation
  between both line terminals
• Two settable alarm levels - Data disturbance
  (detects gaps in a telegram stream) -
  Complete data failure (interruption of the data
  transmission)
• Measurement and compensation of transmission
  duration - max. 30 ms (adaptivily)
• Measurement of the availability of the comms
  link in per/min, per/h Blocking the
  diff.protection if transmission failure rate is
  too high
• Settings for the data transmission (N64
  kBit/s, N settable from 1 - 8, synchronous
  HDLC-protocol)
• Communication device addresses (Protection
  devices are clearly assigned to a defined
  protection section)
• Detection of reflected data in the loops in
  comms- network

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Plug and Protect Commissiong helps and test
features

• Transmission time duration measuement (delay
  time)Mean value of transmit and receive
  direction
• Test loop facility included- Helps to test the
  fibre or comms-link
• Absolute value and phase measurement of
  currentsLocal measurement of angle between IL1,
  IL2, IL3,Angle between currents of each phase
  from remote
• CB test trip
• Counting of faulty telegrams in per minute and
  hour
• Activation of binary inputs and outputs by
  operating software DIGSI 4.
• Display of the status of binary inputs
• Test telegrams to the substation control system
• Test mode which can be activated via DIGSI,
  bin.input- Remote diff. is blocked from the
  local side
• Commissiong mode (diff. runs but doesnt trip)
• Complete commissioning support with DIGSI 4
  andbrowser based PC-software

IL1_2
Phi1-gt2
IL1_1
IL2_1
IL2_2
IL3_2
IL3_1
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Browser view - Startpage with overview
Web-Server is running in the device. Homepage of
the device settable with DIGSI (e.c.
http//140.141.255.150)Serial access to the
device via a standard Dial up Network under
WINDOWS(R)
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Browser view - Local and remote measurements
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Browser view Diff. and restraint measurements
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Comprehensive fault analysis with DIGRA 4
Exact time synchronized fault records from both
line ends
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Prefault and fault conditions in the vector
diagram