protection lecture updated.pdf

8/17/2019 protection lecture updated.pdf

http://slidepdf.com/reader/full/protection-lecture-updatedpdf 1/48

/05/1435

NEPCO

لوطنيشركة لكهربا

Protection

in Electrical System

ئرا

اظم

وا

أ

وا ةزأد

NEPCO


وا مو

ود و رطخ رأ عوو ا تطا و.

و اطت از ل ن أر ذا ار اخطر

طا

در

دائرة

وره

اشره

ن

واد

.

.او ارئ(أظ)ذه اطت دوائر وأزة

دأ اظم ارئ ظ او ن اراض ووع اطل

:

ئرا طا زوو لو دو ل طا:



/05/1435

NEPCO


ئرا

اظم

وا

أ

1-ئرا طا ةدو ن.

.ام اكهبئاتاعطل فيثاح ن-2

.احظ عى سقارة ام اكهبئ-3

NEPCO


1

2

3

5 6

4



/05/1435

NEPCO


اكهبئي

ام

حدات

في

اعطل

ثر

NEPCO


ثر اعطل في حدات ام اكهبئي



/05/1435

NEPCO


ثر اعطل في حدات ام اكهبئي

NEPCO


Auxiliary

Trip Relay

Alarm System

IPCT

IPVT

VT

CT

++

--

110V DC Supply bus wire50V DC Supply bus wire

Main Protective Relay

AC Contact

Timer

وا

دائرة

Trip Coilوت

R

Y

B

إ ادائرة

ا



/05/1435

NEPCO


ئرا تا س

س اطل

ال

د زن خر ظ

إرل اشرة شرة

ز لر لخ ن

زل اطل ن ط أو أر

NEPCO


ئرا مظا وا

ار ال Quick response

اط ارب Simplicity

دا

Reliability

ئاSelectivity

ا

Sensitivity

دا

Economyوا

أزة

خئص



/05/1435

NEPCO


Operating timeOf Relay

Operating time ofauxiliary Relay

closing time ofCircuit breaker

0 s

time

[s]Total operating time of protection circuit

ال

را

Speed

ارار اظم

ن اظم دم ال اطل إ أزا

ل اضرار

إ يدؤ:

NEPCO


Simplicityاط ارب

دا

Reliability

را ل وا ز نو نأ

لاو طض و

ر

ئرإ ط لطا و اذإ لش أن ز او ب أن ون در

ز وذ نو نأ

وأن خو دائرة ا ن اطل

دوز ا تطا لخ ن نخا ا ز ةرد نو



/05/1435

NEPCO


اSensitivity

ئرإ

ط

اطل

و

إذا

ط

أد

شل

ارل

وم

أن

و

أن وم أوأ اظروف

ئرإ ط لط إ ب نأ

K s = If min / Io K s > 1.4

رة اد-- عوضوا ما إ س ا ز ل

خدام أزة خص ط ودد-

-ئخ ر ت ن تو ا ةزأ دوز

.

وطا لو ف

NEPCO


ئاSelectivity

و

:

ن دوث اط- إ ا ز ةرد.

- لطا ط لز ا طاوا وأ طا رخا.

-اط

وظروف

طا

اظروف

ن

ارق

ادرة

.

.ادرة ارق إذا ن اطل ضن ؤو أم -

F2

CB1

F1

CB3 CB4

CB2

A B

X

X

X

X

X

X

X X

G1

G2

C



/05/1435

NEPCO


اد

Economics

إن ور ز ن ل ظرف ن ظروف دإ د رغ رأ وا ئرا مظا.

ا روا با مظا رخا نإ:

- دارا زا وأ ا

أ ا أو از اراد اظم ارئ- ئرا طا عطا رأ ىدو.

NEPCO


:از نوا مظو

وا

وشروع

وا ز

وي واد وا مظ ا ةدوا و

.أو أر ن ات وات وودات اضط

ر ب وأ أد وأ و ب م(ر وأ )

و ط طق ز و واد أو و أزة

ن

و

واب

د

ون

.او اض أو:م دة ب دأ ال ل

ا . طا رغ فرظا بو:

ضرا لطا وأ .... .او ن ارع ار

و دة م ا ظأ ن و قط ط و

ل دارا ةدا:

رغو شا وأ وشروع اول شروع اود



/05/1435

NEPCO


ا ةزأProtective relays

ف أزة

ا

(.روط)رت :-ب ارب -ر تر(ورإ.)

ا ا ب:-را تر.

-طوا

رت

.رت ارد- رت ادر- - .....رغو

ئرا ةرئادا و ب

-ئادا ةزأ(Fuses, MCB’s)

-و ةزأ(Protec. Relays)

ئخ ب-دإ

-دإ -ر

NEPCO


Current Relaysرت ار

رت او ن ارع ار

Over Current Relays (OCR)

ا

ار

رت

Deferential Relays

رت ار و ن دم ازان

Unbalance Relays



/05/1435

NEPCO


Current Relaysرت ار

ئادا

ارت

- إ ةزأ أ إ ج VT’s CT’s DC P/S

- ط ن ةرادا ر ل ل و.

NEPCO


Current Relaysرت اروا ترا

K

L

k

l

-+



/05/1435

NEPCO


a

b

a

b

c

d

e

f

I

1

2

a

b

c

d

f

1

2

I

a bc

f

e

1

2

a

b

c

d

I

اشل ا رت ار

NEPCO


اشل ا رت ار

Current

taps

Induction

disk

Lagging

coil

Timing

dial

Braking

2 4 6

1

2



/05/1435

NEPCO


اف

Stopper

ازان

ذراع

زرك

ات

ار

رل

ل

دأ

=

NEPCO


زا صئخا ب را تر ف

X In

Sec.

دا

Sec.

X In

دا

Sec.

X In

ظ

X In

Sec.

ر



/05/1435

NEPCO


ارت اظ م اول زن اخر اب خدامز تؤ

R

S

T

BK

L

Nk

l

NEPCO


T

4L

2

1

دأ ل ارل اراري ن زدة ار

ز:ئ

ادي

ئ:رارا رد ضخا د إ ل دإ ن



/05/1435

NEPCO


K

l

N3i0=iR +iS+iT

k

IR IS IT

TI0>

L

رت ا ن دم ازان

ودم ل ال ضرا برا تار ن

NEPCO


R

U

+

Sig

طوا ترVoltage Relays

UVR

OVR



/05/1435

NEPCO


Solid State Relays

NEPCO


Solid State Relays

Signal Processing:



/05/1435

NEPCO


Solid State Relays

Comparison Element:

NEPCO


If

0 0.5 1

U ph

U

= % of coil length

ا را ترDeferential Relays

Why?



/05/1435

NEPCO


K Lاز اراد

3

K L

k l lk

i2i1

id=i1- i2

i1 i2

+

Sig.

1 2

I1 I2

ا

ار

رت

Deferential Relays

ا أد ل(را)ارا ن

اراد

از

ن

رخاو

خادا

NEPCO


K L

از اراد

3

K L

k l lk

i2i1

id=i1- i2

i1 i2

+

Sig.

1 2

I1 I2

ا

ار

رت

Deferential Relays

: دم وود طل

I1 = I2 , i1 = i2 & id = i1 – i2

If i1 = i2 then id = 0

: اطلI1 I2 , i1 i2 & id = i1 – i2 0



/05/1435

NEPCO


K Lاز اراد

3

K L

k l lk

i2i1

id=i1- i2

i1 i2

+

Sig.

1 2

I1 I2

ا را ترDeferential Relays

ةد ط م كذر وز ث دأ ال د رور

(10%- 40%)ا

ز

ا

ار

ن

.

Actually i1 i2 :

- Vector group of protected Tr.

- n1 n2

- Outside S/C.

- Prim. Curr. of Protected Tr. Sec. Curr.

- Protected Tr. Have ON Load Tap Changer.

Relay (3) isn't instantaneous relay

NEPCO


i

CT2

CT1

IPVT1

IPVT2

MT



/05/1435

NEPCO


ضا لرا

CT1 CT2

CT3

IPVT2

IPVT3

IPVT1

U1U2

U3

YY

d

Yy0

Yd5

Yd5

Yy0

Yd5

I1 I2

i1

i1’

i3’

i2’

i3

i2

NEPCO


n=5 1

0I

iCT’s Characteristics

5In

Point of

saturation

10In

n=102

n=20 3

20In

I

Unbalance Current



/05/1435

NEPCO


K LK L

k l lk

i2

i1

id = i1- i2=0

i1 i2

1

5

3

2

4

+

is=1/2 (i1+ i2)

ذك د ن رل ار و رل ازان

اشل

وح

رل

أو

Differential Coil

Stabilizing Coil

NEPCO


A

idl

is

iop

iop min

ال ط

i2op = i2

op min + K 2s i2s

K s = tg K sل ات

MMF I2

iS = 0

F in spring

Unbalance current

Operating Characteristics



/05/1435

NEPCO


K LK L

k l lk

i2

i1

2i = i1- i2

i1 i2

1

5

3

2

4

+

0= (i1+ i2)

I1I2

د وود طل از ا ذ ن اطرن ون رات

اشل

و

ارات

NEPCO


ئرا نازا تر

طورا

اوى

خل

ن

شرة

ارات

ر

دأ

ل

is=1/2(i1+i2)

id= i1 - i2

ا زا

TS

Td

i1 i2

I1 I21

2

3 4

Principal of electrical Balance Relay

5

+ Closing

Opening



/05/1435

NEPCO


Moment I iop = iop min + K s is

K s = tg K S & = f(N2 of TS or R)

Not applicable

characteristics

Unbalance current

Operating Characteristics

Non linear resistance or EMF

In stabilizing circuit

A

B

a b

idl

In xIn is

iop

iop min

NEPCO


I1

I2

I>

i1 i2

i1 – i2

id = i1 – i2N2

N2

Ns

Ns

NdNi i2

i2

d

s

i

s

Protec. Element

Magnetic Balance Relay



/05/1435

NEPCO


1

4

3i

ir I

iu

2

u

ur

ر ا غ ف ن

د

زم

ر

رك

و

.ادرة

Mr = K Ur ir Cos(r + ) - Mm

ازم ال اؤر او ار – :Mrث

r – او

طوا

ن

وازا

.

– ر

خادا

وازا

. K – را

رب

د

ت

. Mm – موا ا مزا( كرزا .وغر....اك

Mr = 0 or >0 or <0 Depends on (r + )

To be Operate K Ur ir Cos(r + ) Mm

NEPCO


1

4

(ارت ا)وت رت ادرة

3

i

ir I

iu

2

u

ur



/05/1435

NEPCO


1

4

3i

ir I

iu

2

u

ur

M = k

i

u

sin

i I u U

i

u

iu

I

uIu

U

i = u M = k 1 IU sin(u - )

u = 90 - M = k 1 IU cos( + )

If P = IU cos ( + ) M = k 1 P

NEPCO


P = IU cos ( + ) + (U/2)2 + (I/2)2 - (U/2)2 + (I/2)2

P = (U/2)2 + (UI cos( + ))/2 + (I/2)2 – (U/2)2 - (U/2)2 cos( + ))/2 + (I/2)2

P = U/2 + I/2 2 - U/2 - I/2 2

U

I

|U + I|2 |U - I|2



/05/1435

NEPCO


U

|U + I| |U - I|

U

|U + I| |U - I|

NEPCO


ا لشا ئر نو لضأ تا حرطو عو ر نإ:

R

iu + ii iu - ii

ii

iu

U

ir

Electrical Balance Relays ئرا نازا لر ل أد

Tr 1Tr 2



/05/1435

NEPCO


R

iu + ii iu - ii

ii

iuU

ir

NEPCO


ئرا نازا لر ل أد

R

iu + ii iu - ii

ii

iu

U

ir

IDC (iu + ii)IDC (iu - ii)

ir = iu + ii - iu - ii

ارل

ن

د

ورإ

دائرة

خدم

ا

را

Rارت



/05/1435

NEPCO


iu - ii

iu + ii - iu - ii

ii

iu

iu + ii iu + ii - iu - ii

iu

ii

Lagging iu by

<

Power Direction in the

opposite Bus Direction

<

If the P. Direc. Be changed

The polarity of ir changed

M will change its direction

اراف ن ارات

iu - ii

180

Power Direction assame as Bus Direction

iu + ii

NEPCO


1

4

3i

ir I

iu

2

u

ur

ر ا غ ف ن د مز ر كر و

.ادرة

Mr = K Ur ir Cos(r + ) - Mm

ث

:Mr – ار

او

اؤر

ال

ازم

r

– او

طوا

ن

وازا

.

– ر

خادا

وازا

. K – را بر د ت. Mm –

ازرك )ازم ا اوم .وغر....اك

Mr = 0 or >0 or <0 Depends on (r + )

To be Operate K Ur ir Cos(r + ) Mm



/05/1435

NEPCO


Total Operating Power : Ur ir = Sr [VA]

Sop = Mm / K Cos(r + )

The relay will be very Sensitive

If r + = 0 because of Sop = Sop min

- Angle between Ir & Ur During Fault time

To be operate with max. sensitivity Should

r + =

&Mm = min

Above conditions obtained by Changing using reconnections

NEPCO


In this case : r = + - New angle obtained by reconnections on the Relay terminals

Reconnections can be made by connecting the current circuit on

One phase wile the voltage circuit on the other phase, also by mixing

phase & line voltages & currents together.

=0

Ir Ur

0

Ir Ur

0

30

= - 30

Ir

Ur

0

90

= - 90

>0 , Lagging <0 , Leading



/05/1435

NEPCO


خادا

وازا

ا

وا

إخر

اوول

ن

ا

وغ ذه ارأر د أي زاو طل وغر

ا عاو:

+ = 90 (VAR) Q - relays

Depending on it’s construction these relays can be divided into :

- Induction relays,

- Electro dynamic Relays,

- Electrical Balance Relays.

+ = 30 - 180 (VA) S - relays

+ = 0 (W) P - relays

+ = 180 Reverse Power relays

NEPCO


ا ترا صئخ

ا ترا صئخ رؤ ا ا را:

-خادا وازا()ما ذخو(0, 30, 45, 60, 80, 90, 180) أ د ز نوو

(0 or 90)و اب()ازاو ا ن طر اول-

واوط اوو ارل و ازاو ن اوط ا د ار ارل

- وو اخط ن ات ا وات ا ااخط ازاوي

-ا

وؤد

ارل

إ

خادا

ات

دى

ارى

ا

و

إوا

طا

وا

اخرى

ا

ون

اذي

-را لخد ا ا ما)110 Or 1103 V )أو( 1 or 5 A )و ادة



/05/1435

NEPCO


ا ترا صئخ

ال

ازخئص

اخئص

)P - j Q اوى

ط

(

jQ

P

jQ

P

Not

Operate

=45o

=0o

Error Boundary when U=100% Un

Error Boundary when U=K 1% Un K 1<100%

Error Boundary when U=K 2% Un K 2< K 1

Theoretical Characteristic

Min. op. Power

Actual char. Little bet

deff. From ideal one.

NEPCO


A Theoretical setting valueG Nominal value relay.

Error Boundary when U=100% UnError Boundary when U=K 1% Un K 1<100%

Error Boundary when U=K 2% Un K 2< K 1

Theoretical characteristic

= 0

P

jQ

AG

Actual oper.Char.

of Direc. P Relay



/05/1435

NEPCO


= const.

Operate

Not OperateVoltage

U

Iop

Operating Characteristics of Directional relay as Iop = f(U)

NEPCO


0

30

6090120

150

180

150

6090120

30

Theoretical

Characteristic

Reference

Phase

Direction of

non reference

value

Error Boundary when 100% Reference value Error Boundary when K 1% reference value

Oper. Char. of Direc. relay in polar system = 30



/05/1435

NEPCO


Operating Characteristics of Directional relay as Uop = f(I)

1 2 3

Operate

Not Operate I

Uop

NEPCO


Time Characteristics of Directional relay

P

t (s)

Nom.

power

Set

point



/05/1435

NEPCO


Top.

P

ts or min.

Time Characteristics of Directional relay

NEPCO


ا تراDistance Relays

LTL >> No of TL Supplies >> Complex form Of TL >>

Geographical & Natural Conditions become more Difficult

Probability of Faults becomes more & more

request the protective relays to have a high speed to eliminate the

faults as quick as possible.

0.20.40.60.811.2 1.210.80.60.40.2

Solution: top<< as Lfault <<



/05/1435

NEPCO


G G

A B C D

F1 2 3 4 5 6

Uf Uf


UopUop

Old Criteria : top

U

Disadvantages:- U = f(ZL, If ) top>> as If >>

- Zfault >> so U >> top >>

NEPCO


LiLu

U

i

ا ا ل أد

u = cu1 USC i = ci1 ISC Fu = cu2 u2 Fi = ci2 i

2

Fu Lu= Fi Li cu u2 = ci i

2(u/i)2 = ci/cu = k 1

2

u/I = cu1 USC/ci1 ISC= c Z Z = k 1/c = K



/05/1435

NEPCO


SC

K

Z0 = K

Z = k 1/c = KR 2 + X2 = K

R arc

NEPCO


U

i

k i

ا ا ل أد

u – ki 2 = i2 z = u/i z – k 2 = 1

It’s a vector has ohm character

If the angle between k & z is then : z2 – 2zk cos + k 2 = 1



/05/1435

NEPCO


z2 – 2zk cos + k 2 = 1

k

sc

Z = Kz

Z

2

–

2ZkK cos

+ (kK)

2

= K

2

kK sc

K

NEPCO


K sc

K

For k = 1 Z2 – 2ZK cos + K 2 = K 2

رة ن دائرة ر ط ال و ل خئص اخئص

MOH Relay



/05/1435

NEPCO


ا ا ل أد

K=0 1

iU-k i

|u-k i| |i|+

Sig.

NEPCO


New Criteria : top (U, 1/If )


top = K U/If = K Zline

Zline = Z1 * L & U = I * Z1 * L

These Relays called : Impedance or Distance Relays

Impedance of

length unit

Distance

R - FVoltage where the

Relay build in



/05/1435

NEPCO


ل

ودأ

وت

ا لرا

+ +

+ -

-

-

S D M F

T

NEPCO


t (s)

L (Km)

t4

t3

t2t1

L’1L’2 L’3

ا ترا صئخ



/05/1435

NEPCO



Utr >> & Ltr >>

Protective Distance >>

Ptr >>

Znor. Cond. or ZO/L Zop

Operating Conditions Zline < Zset

و طا ا س أد ل ا ترا

ط ةرادا ر ن را ةرد د م.ارء واظروف اط أو ظروف ال زائد

NEPCO



ذا أح ن ز

اواب

ا

ا

رد

ل

أن

ن

إ

وا

وب

ل

ب

واز

س

أن

ا

ا

ل

س

.

B

A

B’

A’

jX

R

ZL between A & B

R arc + R f.point

At ideal cases relay

Should operate, if the

measured impedance

Less than A-B & s

s : S/C angle of faulty line.

To be relay operated correctly for any fault happened

a long A - B it should has the characteristics above.

But when S/C accurse there is

an additional ohm resistance

Added to the line impedance.

Because of S/C arc.

S

ZS

Zn

At normal cases 0



/05/1435

NEPCO



خف ازاو ن اوط وار ك إ خف ظر

ا

وا

أزة

ف

م

و

ا

ال

و

:

او ا از

Us/Is = Zs

ام از

Impedance

Us/Is Coss = Zs Coss = R s Resistive

Us/Is Sins = Zs Sins = Xs Reactance

Is/Us= 1/Zs = Ys Admitance

Is/Us Coss =Ys Coss = G Conductance

Is/Us Sins =Ys Sins = B Suseptance

NEPCO



أط أواع ذه ازة و

(Impedance Relays)

ن وط ور

واز و.

Zop = const.

Line

D

D

jX

R Zop

If Z < Zop Relay will Operate

Because of Z not f() so

This type of relay need

Directional unit, D - D

Making new reconnections on the relay terminals,

the circle can Be moved left, up, right or down.



/05/1435

NEPCO



R

jX

Zo

Line

Zop

s

Zo = Zop min

Zo = Zop Cos(s - )

= f()

According to internal angle in the relay () Which

determine Zop.min we can draw the following char.

This type of relay need

Directional unit, D - D

NEPCO


Zo = Zop Cos

s = R op = const

For = 0


Changing internal angle ()

We'll obtained deferent

Kinds Of Characteristics

jX

R

D

D

R 0

R op

Line

s



/05/1435

NEPCO


Zo = Zop Sin s = Xop = const = 90


jX

R

D

D

Xop Zop

Line

s

NEPCO


إن ازة ا ل دأ س او ودت

طت

اوب كرا مزا ل ن ذإبا

:

MHO Relays

Line

S

Zop

jX

R

=45

1/Zop * ( Cos (s - ))

ذه ا دائرة طر ور

راد واز ا تادا(.)

= 45ود رت ل ال

Relay will operate when Z < Zop

No need directional unit

for this type of relays

This Relay Called MHO

Relay as an Opposite of

OHM Relays.



/05/1435

NEPCO


MHO Relays

jX

R

Line

S

=0

Conductance Characteristics

NEPCO


jX

R

Line

S

=90

Reactance Characteristics

MHO Relays



/05/1435

NEPCO


ا ضوا ن رو ا ةزأ صئخ ن فدو

ا لشا صئخ تر جإ م:

MHO Relays

S

jX

R

Zop

ZS

Zop

jX

R

NEPCO


ا ز سا ةدو ل ئرا سوا و رأ

ـ ئرا سوا و رد زا تاوا ب:

R a = 28700/(I1.4) /m

خذ ن ار ات ن وال خطوط ال و ر ار (0.5 - 5)ن و اوس ادود

إ (5 – 50)ود ول طور ارض ل أوأ اظروف



/05/1435

NEPCO


إ و ث ظر د ار وأ ط تاذ وا هذو

ئطخ

ارل

در

ون

و

ال

و

إ

. را د ل ا صئخا فخ رأ فخو

For Impedance Relays

R a

ZSZm

jX

R

For MHO Relays (R)

R aZS

Zm

jX

R

NEPCO


For MHO Relays (X)

R a

Zm

ZS

jX

R



/05/1435

NEPCO


Impedance Relays

R a

Zm

ZS

jX

R

NEPCO


Resistance Relays

R aZS

Zm

jX

R



/05/1435

NEPCO


Inductance Relays

jX

R aZS

Zm

R

protection lecture updated.pdf

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