UAT #1 & #2 Protection Relay Setting & Testing

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U

UA

A

AT No.1 & No.2

T No.1 & No.2

T No.1 & No.2 Protection Relay Setting &

Protection Relay Setting &

Protection Relay Setting & Test

Protection Relay Setting &

Test

Testing

ing

1. Setting of UAT #1 Protection Relay - - - P. 3 – P13

2. UAT #1 Protection Relay Test Record Sheet - - - P.14 – P.21

3. Setting of UAT #2 Protection Relay - - - P. 22 – P.32

4. UAT #2 Protection Relay Test Record Sheet - - - P. 33 – P.40

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Setting of UAT-1 Protection Relay Type RET670

F87T - Unit Aux. Transformer Differential Protection

1. Terminal identification

Station Name : KERAMASAN

Bay Name: UAT-1

Relay Name RET 670

Relay serial No

Frequency 50 Hz

Aux voltage 110 VDC

2. General Data

Transformer: GSUT-1, two winding

Rated data : Rated power 6 MVA

Voltage ratio 11 kV / 6.3 kV

W1 rated current - Ir1 315 A W2 rated current - Ir2 550 A

Connection Dyn11 (resistive grounding at Y winding)

p.u. Impedance 0.08 at Base 6 CT ratio W1 (11kV) 750 / 1 A CT ratio W2 (6.3kV) 1250 / 1 A VT ratio W1 11 / 0.11 kV VT ratio W2/W3 6.3 / 0.11 kV

Short circuit data :

Three-phase short circuit current at 6.3kV busbar 9300 A Phase to Ground short circuit current at 6.3kV busbar 11 A Phase current contribution of UAT for 3-Ph fault at 6.3kV busbar 6580 A measured at 6.3kV side

Phase current contribution of UAT for 3-Ph fault at 6.3kV busbar 3768.5 A measured at 11kV side

3. Setting Considerations

Protection Scheme

- Transformer 2 winding differential protection (87T) is applied as main

protection to mostly protect the transformer from internal phase to phase fault. Very small earth fault current due to resistive grounding makes REF protection will not be effective and sensitive enough to protect the transformer from internal earth fault. Therefore, sensitive earth fault protection relay shall then be provided in the backup protection relay.

Differential current setting (Idmin)

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The usual practice for transformer protection is to set the bias characteristic to a value of at least twice the value of the expected spill current under

through faults conditions. Spill current may arise from several conditions such as : - transformer phase shift and ratio error

- current transformer ratio error - different CTs characteristic

Idmin of 0.3 x Ibase is normally recommended to be applied. Zero-sequence current substraction

A differential protection may operate unwanted due to external earth faults in cases where the zero sequence current can flow only on one side of the power transformer but not on the other side. This is the situation when the zero sequence current can not be properly transformed to the other side of the power transformer having a combined Y and D connection group. In such case, the zero sequence substraction function shall be set ON for Y winding and OFF for D winding.

4. Setting of analogue input

Configure analogue inputs for TRM1 (-X401) : Set analogue current channels

AI1 AI2 AI3 AI4 AI5

Ctprim = 750 750 750 1250 1250

Ctsec = 1 A 1 A 1 A 1 A 1 A

CTStarPoint = To Object To Object To Object To Object To Object

AI6 AI7 AI8 AI9

Ctprim = 1250 not used not used not used

Ctsec = 1 A not used not used not used

CTStarPoint = To Object not used not used not used Set analogue voltage channels

AI10 AI11 AI12

Vtprim = not used not used not used

Vtsec = not used not used not used

5. Protection Settings

5.1. Setting of the Differential function data under T2WPDIF General settings.

Winding 1 (W1) Winding 2 (W2) RatedVoltageW1 11 kV RatedVoltageW2 6.3 kV RatedCurrentW1 315 A RatedCurrentW2 550 A ConnectTypeW1 D ConnectTypeW2 Y TconfigForW1 No TconfigForW2 No CT1ratingW1 750 A CT1ratingW2 1250 A

ZSCurrSubtrW1 Off ZSCurrSubtrW2 On

ClockNumberW2 11

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Note : All other setting parameters under general setting are not relevant. Use default values.

5.2. Differential Protection Setting (87T) under T2WPDIF Setting group:

Operation = On

Operation of SOTF feature

SOTFMode = Off

Setting of differential current alarm

IDiffAlarm = 0.2 *Ibase Setting of time delay of differential current alarm

tAlarmDelay = 10 s

Setting of minimum differential operating current

IdMin = 0.3 *Ibase Setting of cross-over point between slope 1 and slope 2

EndSection1 = 1.25 Ibase Setting of slope 2 stabilisation, Slope 1 has fixed stabilization

SlopeSection2 = 40% *Ibias Setting of cross-over point between slope 2 and slope 3

EndSection2 = 3.00 Ibase Setting of slope 2 stabilisation

SlopeSection3 = 80% *Ibias

Setting of minimum differential operating current for unrestraint step Idunre = 20.00 *Ibase Set the operation of Cross Blocking logic On-Off

OpCrossBlock = On

Set the second and fifth harmonic stabilizing level when transformers are inside the zone

I2/I1Ratio = 15%

I5/I1Ratio = 25%

Set the operation of Negative sequence differential protection

NegSeqDiffEn = No

Setting of minimum negative sequence differential current level

IMinNegSeq = 0.04

Setting of the Relay operating angles

NegSeqROA = 60 deg

Set the operation of Open CT detection

OpenCTEnable = No

Note : All other setting parameters under this setting group are not relevant.

5.3. All other protection functions

Operation = Off

6. Assignment of Binary Input BIM_3

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BIM_3.BI01 : Bucholz Trip

BIM_3.BI02 : Rapid Pressure Relay Trip

BIM_3.BI03 : Oil Level Low Low Trip

BIM_3.BI04 : Protective Relay Trip

BIM_3.BI05 : Oil Temperature Trip

BIM_3.BI06 : HV Winding Temperature Trip

BIM_3.BI07 : Not used

BIM_3.BI08 : Trip from Generator Protection (59BG)

BIM_3.BI09 : Trip from Generator Protection (52G Mech Fail)

BIM_3.BI10 : Trip from GSUT Protection

BIM_3.BI11 : Reset Lockout BIM_3.BI12 : Not used

7. Assignment of Binary Output BOM_4

BOM_4.BO01 : Transformer Differential Trip (T2WPDIF) BOM_4.BO02 : Not used

BOM_4.BO03 : Trip from Generator Protection

BOM_4.BO04 : Trip from UAT Transformer's Protection (Bucholz etc) BOM_4.BO05 : Not used

BOM_4.BO06 : Not used

BOM_4.BO13 : Trip from UAT Transformer's Protection (Bucholz etc) BOM_4.BO14 : Trip from GSUT Protection

BOM_4.BO17 : Trip from GSUT Protection

BOM_4.BO18 : Trip from Generator Protection BOM_4.BO19 : Not used

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Setting of UAT-1 Protection Relay Type REF615

F5051 - Backup OC & EF Protection

1. Terminal identification

Station Name KERAMASAN

Bay Name: UAT-1

Relay Name REF615

Relay serial No

Frequency 50 Hz

Aux voltage 110 VDC

2. General Data

Transformer: UAT-1, two winding

p.u. Impedance 0.08

at Base 6

CT ratio W1 (11kV) 750 / 1 A

CT ratio W2 (6.3kV) 1250 / 1 A

Maximum tripping time for 6.3kV outgoing feeders Instantaneous

3. Setting Considerations

Protection Scheme

- Low-set phase overcurrent (51) protection at 11kV side are used as backup protection for differential (87T) and REF (87REF) protection.

To maintain selectivity against downstream protection relays, a time delay of 0.5s on top of the downstream (6.3kV outgoing feeders) protection relays maximum operating time shall be introduced.

- Instantaneous-set overcurrent (50) at 11kV side is applied to protect the transformer during short circuit condition. Time delay shall be introduced to maintain selectivity from the fault which occur at the other parts of the system.

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- Sensitive earth fault/SEF (50S) of this relay will be applied at 6.3kV to detect earth fault condition at 6.3kV system. To maintain selectivity against earth fault protection relay at 6.3kV outgoing feeders, a time delay of 0.5s on top of the

outgoing feeders tripping time is introduced. As the fault current is considerably small, a longer operating time is somehow still acceptable as long as not exceeding the rated time of NGR (10s).

- To avoid unwanted operation of the overcurrent and earth fault protection due to inrush current during transformer startup, the inrush detection element INRPHAR is activated to give a blocking signal to the overcurrent & earth fault element when inrush current is detected.

4. Setting of analogue input

Analog input settings, phase currents

Secondary current = 1 A

Primary current = 750 A

Amplitude corr. A = 1

Amplitude corr. B = 1

Amplitude corr. C = 1

Nominal current = 315 A {In}

Rated secondary value = 3 mV/Hz

Reverse polarity = 0 {False}

Analog input settings, residual currents

Amplitude corr. = 1

5. General System Setting

Rated frequency = 50 Hz

Phase rotation = ABC

Blocking mode = Freeze timer

Bay Name = UAT2

IDMT saturation point = 50

6. Setting of Three Phase Overcurrent Function (PHxPTOC) on 11 kV side

6.1. PHIPTOC (Instantaneous) Non group settings:

Activation of the PHIPTOC function

Operation = 1 { 1=On }

Number of phases required for operate activation

Num of start phase = 1 { 1=1-out-of-3 }

Reset delay time

Reset delay time = 20 ms { instantaneous }

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6.2. PHIPTOC (Instantaneous) Group settings:

Start values is set at 130% of transformer short circuit current to get selectivity with faults at 6.3kV. Start Value PHHPTOC = 130% x 3768.5 A

= 4899.1 A Start Value PHHPTOC = 15.6 x In Operate delay time

Operate delay time = 20 ms { instantaneous }

Note : All other setting parameters are not relevant. Default values can be used.

6.3. PHHPTOC (high-set) Non group settings:

Activation of the PHHPTOC function

Operation = 5 { 5=Off }

6.4. Setting of parameters for PHLPTOC (low-set) Non-group Setting

Activation of the PHLPTOC function

Number of phases required for activation

Num of start phase = 1 out of 3 Minimum operate time for IDMT curve

Min. oper. Time = 40 ms

Reset delay time

Reset delay time = 20 ms

Curve parameter for programmable curve

Curve parameter A, B, C, D, E = default {NA}

6.5. PHLPTOC (low-set) Group settings:

Start values is set at 110% of transformer rated current.

Start Value PHLPTOC = 120% x 315 A

= 378 A

Start Value PHLPTOC = 1.2 x In Multiplier for scalng the start value

Start value Mult = 1 Time multiplier setting (TMS)

Time multiplier = 1 {See note below}

Operate delay time

Time delay PHLPTOC = 400 ms {Not relevant for inverse type}

Operating curve type

Curve PHLPTOC = IEC Extremely Inverse Selection of reset curve type

Type of reset curve = 1 {Immediate}

Note : Time delayed PHLPTOC shall be set to operate in about 0.8 s at short circuit

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current to give safe margin to the transformer main protection and other unit protection at the other part of the system.

Short circuit current = 3768.5 A = 12 x In

with start value = 1.2 x In

and set time multiplier = 1

for extremely inverse curve, the operating time t is : t = 0.814 s --> OK

7. Setting of Earth Fault Protection Function (EFxPTOC) on 6.3 kV side

7.1. EFIPTOC (Instantaneous) Non group settings:

Activation of the EFIPTOC function

7.2. EFHPTOC (high-set) Non group settings:

Activation of the EFHPTOC function

7.3. EFLPTOC (low-set) Non group settings:

Activation of the EFLPTOC function

Minimum operate time for IDMT curve

Reset delay time

Selection for used Io signal

Io signal Sel = 1 {Measured Io)

7.3. EFLPTOC (low-set) Group settings:

Start value for earth fault is set at 50% of maximum earth fault current.

Start Value EFLPTOC = 50% x 11 A {See note below}

= 6 A

Start Value EFLPTOC = 0.02 x In Multiplier for scalng the start value

Time multiplier = 0.1 {See note below}

Operate delay time

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Time delay EFLPTOC = 0.9 s Operating curve type

Curve EFLPTOC = Definite time Selection of reset curve type

8. Setting of Inrush Detector INRPHAR

8.1. Inrush Detector INRPHAR Group Setting

Ratio of the 2nd to the 1st harmonic leading to restraint

Start value = 0.15 %

Operate delay time

Operate delay time = 20 ms

8.2. Inrush Detector INRPHAR Non Group Setting

Activation of the INRPHAR function

Reset delay time

9. All other protection functions

10. Assignment of Binary Input

Binary Input Terminal -X110_

BI1 : Not used

BI2 : Not used

BI3 : Not used

BI4 : Not used

BI5 : Not used

BI6 : Not used

BI7 : Not used

BI8 : Not used

BI9 : Not used

BI10 : Not used

Binary Input Terminal -X120_ BI1

BI2 BI3

BI4 : Reset lockout

11. Assignment of Binary Output

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Binary Output Terminal -X100_

PO1 : Overcurrent Trip

(Operation of PHHPTOC, PHLPTOC) PO2 : SEF Trip

(Operation of EFLPTOC) SO1 : Overcurrent Trip

SO2 : SEF Trip PO3

PO4

SO1 : Overcurrent Trip SO2 : SEF Trip SO3

SO4

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Equipment : Feeder : 1. Reference Drawing Schematic Diagram : Transformer Bay : 2. General Data Manufacture : Designation :

Type : Sereal No. :

3. Commissioning Tests 3.1 Visual Check

a) Physically Good ? :

b) Relay Healthy ? :

c) Mounting and wiring completed ? :

Protection Relay Test

Unit Aux. Transformer Differential Protection Relay RET670

UAT #1 KPP-00-TPS-W-141 11kV 6.3kV UAT #1 ABB RET670 F87T

3.2 Verifying the connections and the analog inputs

Apply input signals as needed and verify that signals are measured correctly

1 2 3 4 5 6 7

No. Procedure Injected Values

Secondary

Measured

Values Primary Remarks

Inject current phase R → A101 A A

Inject current phase R → A104 A A Inject current phase S → A105 A A Inject current phase S → A102 A A Inject current phase T → A103 A A

Inject current phase T → A106 A A Inject current Neutral → A107 A A

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3.3 Deferential Protection Test

(1) Check on HV side Secondary Injection

No. Procedure Items to be verified. Remarks

1 Make sure that REF and OC / EF function are set to off.

2 Connect the test set for injection of 3 phase current to the current terminals of RET670 which are connected to the CT's on HV side of transformer

3 Increase the current in phase L1 until the protection operates and check

L1

a) the operating current (Iop) a) Iop : A b) Trip contacts operation b) Trip contact :

Operate / Not operate c) Alarm contact operation c) Alarm contact :

a) Iop : A b) Trip contacts operation b) Trip contact :

Operate / Not operate 4 Increase the current in phase L2 until

the protection operates and check

L2 For stable condition,

Trip not operated

a) the operating current (Iop)

Operate / Not operate

For stable condition, Trip not operated

Operate / Not operate Operate / Not operate 5 Increase the current in phase L3 until

the protection operates and check L3

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(2) Check on LV side Secondary Injection

c) Alarm contact operation c) Alarm contact :

Operate / Not operate 1 Connect the test set for injection of 3

phase current to the current terminals of RET670 which are connected to the CT's on LV side of transformer

L2

4 Increase the current in phase L3 until L3

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3.4 6.3kV Restricted EF Protection Test

(1) Secondary Injection

No.

4. Remarks :

Procedure Items to be verified. Remarks 1 Make sure that Differential protection

and OC/EF function are set to off.

2 Connect the test set for injection of neutral current to the current terminals of RET670 to which the NCT 20kV is connected

3 Increase the current in until the protection operates and check

L1

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Type : Sereal No. :

Protection Relay Test

Backup OC & EF Protection Relay REF615

UAT #1 KPP-00-TPS-W-141 11kV 6.3kV UAT ABB RET615 F5051 1VHR91059397

1 2 3 4

Secondary

Measured

Inject current phase T A A

Inject current phase N A A

Inject current phase R A A

Inject current phase S A A

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3.3 Testing of the phase overcurrent protection

The test is performed as a secondary test, by injecting current to the current energizing inputs with the setting values used during normal operation

No.

2 Inject the current (Ii) in phase L2

Procedure Items to be verified. Remarks 1 Inject the current (Ii) in phase L1

Ii = 2.5 * I > * rated current input Start of stage I > : .

I > setting : * In

I > setting : * In Trip of stage I > : . t > setting : s Operation time : s Trip of stage I > : . t > setting : s Operation time : s

I > setting : * In Trip of stage I > : .

t > setting : s

Operation time : s

Ii = 8 * I >>> * rated current input Start of stage I >>> : .

I >>> setting : * In Trip of stage I >>> : .

t >>> setting : s

Operation time : s

t >>> setting : s

Operation time : s

6 Inject the current (Ii) in phase L3 5 Inject the current (Ii) in phase L2

I >>> setting : * In Trip of stage I >>> : . t >>> setting : s Operation time : s

Contractor

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3.4 Testing of the earth fault protection

No.

4. Remarks :

Start of stage I > : .

I0 > setting : * In Trip of stage I > :

.

2 Inject the current (Ii) in the earth fault

Procedure Items to be verified.

energizing input :

Ii = 2.5 * I0 >> * rated current input Start of stage I >> :

.

I0 >> setting : * In Trip of stage I >> :

.

t0 >> setting : s Operation time :

s

Remarks 1 Inject the current (Ii) in the earth fault

energizing input :

Ii = 2.5 * I0 > * rated current input

t0 > setting : s Operation time :

s

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Setting of UAT-2 Protection Relay Type RET670

F87T - Unit Aux. Transformer Differential Protection

1. Terminal identification

Station Name : KERAMASAN

Bay Name: UAT-2

Relay Name RET 670

Relay serial No

Frequency 50 Hz

Aux voltage 110 VDC

2. General Data

Transformer: GSUT-2, two winding

p.u. Impedance 0.08 at Base 6 CT ratio W1 (11kV) 750 / 1 A CT ratio W2 (6.3kV) 1250 / 1 A VT ratio W1 11 / 0.11 kV VT ratio W2/W3 6.3 / 0.11 kV

3. Setting Considerations

Protection Scheme

- Transformer 2 winding differential protection (87T) is applied as main

protection to mostly protect the transformer from internal phase to phase fault. Very small earth fault current due to resistive grounding makes REF protection will not be effective and sensitive enough to protect the transformer from internal earth fault. Therefore, sensitive earth fault protection relay shall then be provided in the backup protection relay.

Differential current setting (Idmin)

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The usual practice for transformer protection is to set the bias characteristic to a value of at least twice the value of the expected spill current under

through faults conditions. Spill current may arise from several conditions such as : - transformer phase shift and ratio error

- current transformer ratio error - different CTs characteristic

Idmin of 0.3 x Ibase is normally recommended to be applied. Zero-sequence current substraction

A differential protection may operate unwanted due to external earth faults in cases where the zero sequence current can flow only on one side of the power transformer but not on the other side. This is the situation when the zero sequence current can not be properly transformed to the other side of the power transformer having a combined Y and D connection group. In such case, the zero sequence substraction function shall be set ON for Y winding and OFF for D winding.

4. Setting of analogue input

Configure analogue inputs for TRM1 (-X401) : Set analogue current channels

AI1 AI2 AI3 AI4 AI5

Ctprim = 750 750 750 1250 1250

Ctsec = 1 A 1 A 1 A 1 A 1 A

CTStarPoint = To Object To Object To Object To Object To Object

AI6 AI7 AI8 AI9

Ctprim = 1250 not used not used not used

Ctsec = 1 A not used not used not used

CTStarPoint = To Object not used not used not used Set analogue voltage channels

AI10 AI11 AI12

Vtprim = not used not used not used

Vtsec = not used not used not used

5. Protection Settings

5.1. Setting of the Differential function data under T2WPDIF General settings.

Winding 1 (W1) Winding 2 (W2) RatedVoltageW1 11 kV RatedVoltageW2 6.3 kV RatedCurrentW1 315 A RatedCurrentW2 550 A ConnectTypeW1 D ConnectTypeW2 Y TconfigForW1 No TconfigForW2 No CT1ratingW1 750 A CT1ratingW2 1250 A

ZSCurrSubtrW1 Off ZSCurrSubtrW2 On

ClockNumberW2 11

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Note : All other setting parameters under general setting are not relevant. Use default values.

5.2. Differential Protection Setting (87T) under T2WPDIF Setting group:

Operation = On

Operation of SOTF feature

SOTFMode = Off

Setting of differential current alarm

IDiffAlarm = 0.2 *Ibase Setting of time delay of differential current alarm

tAlarmDelay = 10 s

Setting of minimum differential operating current

IdMin = 0.3 *Ibase Setting of cross-over point between slope 1 and slope 2

EndSection1 = 1.25 Ibase Setting of slope 2 stabilisation, Slope 1 has fixed stabilization

SlopeSection2 = 40% *Ibias Setting of cross-over point between slope 2 and slope 3

EndSection2 = 3.00 Ibase Setting of slope 2 stabilisation

SlopeSection3 = 80% *Ibias

Setting of minimum differential operating current for unrestraint step Idunre = 20.00 *Ibase Set the operation of Cross Blocking logic On-Off

OpCrossBlock = On

Set the second and fifth harmonic stabilizing level when transformers are inside the zone

I2/I1Ratio = 15%

I5/I1Ratio = 25%

Set the operation of Negative sequence differential protection

NegSeqDiffEn = No

Setting of minimum negative sequence differential current level

IMinNegSeq = 0.04

Setting of the Relay operating angles

NegSeqROA = 60 deg

Set the operation of Open CT detection

OpenCTEnable = No

Note : All other setting parameters under this setting group are not relevant.

5.3. All other protection functions

Operation = Off

6. Assignment of Binary Input BIM_3

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BIM_3.BI01 : Bucholz Trip

BIM_3.BI02 : Rapid Pressure Relay Trip

BIM_3.BI03 : Oil Level Low Low Trip

BIM_3.BI04 : Protective Relay Trip

BIM_3.BI05 : Oil Temperature Trip

BIM_3.BI06 : HV Winding Temperature Trip

BIM_3.BI08 : Trip from Generator Protection (59BG)

BIM_3.BI09 : Trip from Generator Protection (52G Mech Fail)

BIM_3.BI10 : Trip from GSUT Protection

BIM_3.BI11 : Reset Lockout BIM_3.BI12 : Not used

7. Assignment of Binary Output BOM_4

BOM_4.BO04 : Trip from UAT Transformer's Protection (Bucholz etc) BOM_4.BO05 : Not used

BOM_4.BO13 : Trip from UAT Transformer's Protection (Bucholz etc) BOM_4.BO14 : Trip from GSUT Protection

BOM_4.BO17 : Trip from GSUT Protection

BOM_4.BO18 : Trip from Generator Protection BOM_4.BO19 : Not used

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Setting of UAT-2 Protection Relay Type REF615

F5051 - Backup OC & EF Protection

1. Terminal identification

Station Name KERAMASAN

Bay Name: UAT-2

Relay Name REF615

Relay serial No

Frequency 50 Hz

Aux voltage 110 VDC

2. General Data

Transformer: UAT-2, two winding

p.u. Impedance 0.08

at Base 6

CT ratio W1 (11kV) 750 / 1 A

CT ratio W2 (6.3kV) 1250 / 1 A

Maximum tripping time for 6.3kV outgoing feeders Instataneous

3. Setting Considerations

Protection Scheme

- Low-set phase overcurrent (51) protection at 11kV side are used as backup protection for differential (87T) and REF (87REF) protection.

To maintain selectivity against downstream protection relays, a time delay of 0.5s on top of the downstream (6.3kV outgoing feeders) protection relays maximum operating time shall be introduced.

- High-set overcurrent (50) at 11kV side is applied to protect the transformer during short circuit condition. Time delay shall be introduced to maintain selectivity from the fault which occur at the other parts of the system.

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- Sensitive earth fault/SEF (50S) of this relay will be applied at 6.3kV to detect earth fault condition at 6.3kV system. To maintain selectivity against earth fault protection relay at 6.3kV outgoing feeders, a time delay of 0.5s on top of the

outgoing feeders tripping time is introduced. As the fault current is considerably small, a longer operating time is somehow still acceptable as long as not exceeding the rated time of NGR (10s).

- To avoid unwanted operation of the overcurrent and earth fault protection due to inrush current during transformer startup, the inrush detection element INRPHAR is activated to give a blocking signal to the overcurrent & earth fault element when inrush current is detected.

4. Setting of analogue input

Analog input settings, phase currents

Amplitude corr. A = 1

Amplitude corr. B = 1

Amplitude corr. C = 1

Nominal current = 315 A {In}

Rated secondary value = 3 mV/Hz

Analog input settings, residual currents

Amplitude corr. = 1

5. General System Setting

Rated frequency = 50 Hz

Phase rotation = ABC

Blocking mode = Freeze timer

Bay Name = UAT2

IDMT saturation point = 50

6. Setting of Three Phase Overcurrent Function (PHxPTOC) on 11 kV side

6.1. PHIPTOC (Instantaneous) Non group settings:

Activation of the PHIPTOC function

Number of phases required for operate activation

Num of start phase = 1 { 1=1-out-of-3 }

Reset delay time

Reset delay time = 20 ms { instantaneous }

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6.2. PHIPTOC (Instantaneous) Group settings:

Start values is set at 130% of transformer short circuit current to get selectivity with faults at 6.3kV. Start Value PHHPTOC = 130% x 3768.5 A

= 4899.1 A Start Value PHHPTOC = 15.6 x In Operate delay time

Operate delay time = 20 ms { instantaneous }

6.3. PHHPTOC (high-set) Non group settings:

Activation of the PHHPTOC function

6.4. Setting of parameters for PHLPTOC (low-set) Non-group Setting

Activation of the PHLPTOC function

Number of phases required for activation

Num of start phase = 1 out of 3 Minimum operate time for IDMT curve

Reset delay time

6.5. PHLPTOC (low-set) Group settings:

Start values is set at 110% of transformer rated current.

Start Value PHLPTOC = 120% x 315 A

= 378 A

Start Value PHLPTOC = 1.2 x In Multiplier for scalng the start value

Time multiplier = 1 {See note below}

Operate delay time

Time delay PHLPTOC = 400 ms {Not relevant for inverse type}

Curve PHLPTOC = IEC Extremely Inverse Selection of reset curve type

Note : Time delayed PHLPTOC shall be set to operate in about 0.8 s at short circuit current to give safe margin to the transformer main protection and other

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unit protection at the other part of the system. Short circuit current = 3768.5 A

= 12 x In

with start value = 1.2 x In

and set time multiplier = 1

for extremely inverse curve, the operating time t is : t = 0.814 s --> OK

7. Setting of Earth Fault Protection Function (EFxPTOC) on 6.3 kV side

7.1. EFIPTOC (Instantaneous) Non group settings:

Activation of the EFIPTOC function

7.2. EFHPTOC (high-set) Non group settings:

Activation of the EFHPTOC function

7.3. EFLPTOC (low-set) Non group settings:

Activation of the EFLPTOC function

Minimum operate time for IDMT curve

Reset delay time

Selection for used Io signal

Io signal Sel = 1 {Measured Io)

7.3. EFLPTOC (low-set) Group settings:

Start value for earth fault is set at 50% of maximum earth fault current.

Start Value EFLPTOC = 50% x 11 A {See note below}

= 6 A

Start Value EFLPTOC = 0.02 x In Multiplier for scalng the start value

Time multiplier = 0.1 {See note below}

Operate delay time

Time delay EFLPTOC = 0.9 s

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Curve EFHPTOC = Definite time Selection of reset curve type

8. Setting of Inrush Detector INRPHAR

8.1. Inrush Detector INRPHAR Group Setting

Ratio of the 2nd to the 1st harmonic leading to restraint

Start value = 0.15 %

Operate delay time

Operate delay time = 20 ms

8.2. Inrush Detector INRPHAR Non Group Setting

Activation of the INRPHAR function

Reset delay time

9. All other protection functions

10. Assignment of Binary Input

Binary Input Terminal -X110_

BI1 : Not used

BI2 : Not used

BI3 : Not used

BI4 : Not used

BI5 : Not used

BI6 : Not used

BI7 : Not used

BI8 : Not used

BI9 : Not used

BI10 : Not used

Binary Input Terminal -X120_ BI1

BI2 BI3

BI4 : Reset lockout

11. Assignment of Binary Output

(31)

PO1 : Overcurrent Trip

(Operation of PHHPTOC, PHLPTOC) PO2 : SEF Trip

(Operation of EFLPTOC) SO1 : Overcurrent Trip

SO2 : SEF Trip PO3

PO4

SO1 : Overcurrent Trip SO2 : SEF Trip SO3

SO4

(32)

(33)

Type : Sereal No. :

RET670

Protection Relay Test

Unit Aux. Transformer Differential Protection Relay RET670

UAT #2

KPP-00-TPS-W-141 11kV 6.3kV UAT #2

ABB F87T

1 2 3 4 5 6 7

Secondary

Measured

Inject current phase T → A103 A A Inject current phase R → A104 A A Inject current phase R → A101 A A Inject current phase S → A102 A A

Inject current Neutral → A107 A A Inject current phase S → A105 A A Inject current phase T → A106 A A

(34)

3.3 Deferential Protection Test

(1) Check on HV side Secondary Injection

Operate / Not operate 1 Make sure that REF and OC / EF

function are set to off.

2 Connect the test set for injection of 3 phase current to the current terminals of RET670 which are connected to the CT's on HV side of transformer

the protection operates and check L2 3 Increase the current in phase L1 until

Operate / Not operate Operate / Not operate c) Alarm contact operation c) Alarm contact :

(35)

(2) Check on LV side Secondary Injection

No. Procedure Items to be verified.

a) Iop : A b) Trip contacts operation b) Trip contact :

Remarks 1 Connect the test set for injection of 3

phase current to the current terminals of RET670 which are connected to the CT's on LV side of transformer

L1

a) the operating current (Iop)

Operate / Not operate 4 Increase the current in phase L3 until L3

(36)

3.4 6.3kV Restricted EF Protection Test

(1) Secondary Injection

No.

4. Remarks :

Procedure Items to be verified. Remarks 1 Make sure that Differential protection

and OC/EF function are set to off.

2 Connect the test set for injection of neutral current to the current terminals of RET670 to which the NCT 20kV is connected

3 Increase the current in until the protection operates and check

L1

(37)

Type : Sereal No. :

UAT #2

KPP-00-TPS-W-141 11kV 6.3kV UAT

ABB F5051

RET615

Protection Relay Test

Backup OC & EF Protection Relay REF615

1 2 3 4

Secondary

Measured

Inject current phase R A A

Inject current phase N A A

Inject current phase S A A

Inject current phase T A A

(38)

3.3 Testing of the phase overcurrent protection

t > setting : s

Operation time : s

t > setting : s

Operation time : s

t > setting : s

Operation time : s

t >>> setting : s

Operation time : s

5 Inject the current (Ii) in phase L2 5 Inject the current (Ii) in phase L2

t >>> setting : s

Operation time : s

I >>> setting : * In Trip of stage I >>> : . t >>> setting : s Operation time : s

Contractor

(39)

3.4 Testing of the earth fault protection

No.

4. Remarks :

Remarks 1 Inject the current (Ii) in the earth fault

energizing input :

Ii = 2.5 * I0 > * rated current input Start of stage I > :

.

I0 > setting : * In Trip of stage I > :

.

t0 > setting : s Operation time :

s 2 Inject the current (Ii) in the earth fault

Procedure Items to be verified.

energizing input :

Ii = 2.5 * I0 >> * rated current input Start of stage I >> :

.

I0 >> setting : * In Trip of stage I >> :

.

t0 >> setting : s Operation time :

s

UAT #1 & #2 Protection Relay Setting & Testing

U

U

U

UA

A

A

AT No.1 & No.2

T No.1 & No.2

T No.1 & No.2

T No.1 & No.2 Protection Relay Setting &

Protection Relay Setting &

Protection Relay Setting & Test

Protection Relay Setting &

Test

Test

Testing

ing

ing

ing

Contents

1. Setting of UAT #1 Protection Relay - - - P. 3 – P13

2. UAT #1 Protection Relay Test Record Sheet - - - P.14 – P.21

3. Setting of UAT #2 Protection Relay - - - P. 22 – P.32

4. UAT #2 Protection Relay Test Record Sheet - - - P. 33 – P.40

Setting of UAT-1 Protection Relay Type RET670

F87T - Unit Aux. Transformer Differential Protection

1. Terminal identification

2. General Data

3. Setting Considerations

4. Setting of analogue input

5. Protection Settings

5.1. Setting of the Differential function data under T2WPDIF General settings.

5.2. Differential Protection Setting (87T) under T2WPDIF Setting group:

5.3. All other protection functions

6. Assignment of Binary Input BIM_3

7. Assignment of Binary Output BOM_4

Setting of UAT-1 Protection Relay Type REF615

F5051 - Backup OC & EF Protection

1. Terminal identification

2. General Data

3. Setting Considerations

4. Setting of analogue input

5. General System Setting

6. Setting of Three Phase Overcurrent Function (PHxPTOC) on 11 kV side

7. Setting of Earth Fault Protection Function (EFxPTOC) on 6.3 kV side

8. Setting of Inrush Detector INRPHAR

8.1. Inrush Detector INRPHAR Group Setting

8.2. Inrush Detector INRPHAR Non Group Setting

9. All other protection functions

10. Assignment of Binary Input

11. Assignment of Binary Output

Protection Relay Test

Protection Relay Test

Contractor

Setting of UAT-2 Protection Relay Type RET670

F87T - Unit Aux. Transformer Differential Protection

1. Terminal identification

2. General Data

3. Setting Considerations

4. Setting of analogue input

5. Protection Settings

5.1. Setting of the Differential function data under T2WPDIF General settings.

5.2. Differential Protection Setting (87T) under T2WPDIF Setting group:

5.3. All other protection functions

6. Assignment of Binary Input BIM_3

7. Assignment of Binary Output BOM_4

Setting of UAT-2 Protection Relay Type REF615

F5051 - Backup OC & EF Protection

1. Terminal identification

2. General Data

3. Setting Considerations

4. Setting of analogue input

5. General System Setting

6. Setting of Three Phase Overcurrent Function (PHxPTOC) on 11 kV side

7. Setting of Earth Fault Protection Function (EFxPTOC) on 6.3 kV side

8. Setting of Inrush Detector INRPHAR

8.1. Inrush Detector INRPHAR Group Setting

8.2. Inrush Detector INRPHAR Non Group Setting

9. All other protection functions