المحتويات:

1 .......................................................................................................................................... المقدمة

2 ............................................................................... المصطلحات المستعملة في مجال حماية النظم الكهربية

5 ............................................................................................................ الحماية )المرحالت( أجهزةدور

7 ....................................................................................................... الحماية أجهزةعمل وأسلوبوظيفة

8 ..................................................................................................... لعمل دائرة الحماية األساسيةالمبادئ

10 ......................................................................................................... الحماية ألجهزةة المتطلبات العام

15 ................................................................................................... الحماية الرئيسية والحماية االحتياطية

٢

-1 -

אאאא

אאאאאאאאאאK

א א א א א א א אא

אאאאאאKאאאאאאאאאאא

א א א א א א א א א אאאאא

EKאאאFאאאא אא א א א

אאאאאאאאKאא

א א א א א אא א אא א א א אא א א K

אאאאאאאאK

٢

-2 -

אאאא

• FNormalE א א א אא א

אאאK • FRelays E א א א א אא

אא א ،א א א א אאאAbnormal FאאאKE

• אNormally Open Contact (NOC) אא

א א K אא אאאאKאאא

אאאאאאאאאאK

• Normally Closed Contact (NCC)אא

אאKאאאKאF

א אE Fא א E K אאאאKא

אא א א K אאK

• אא Primary Relays

אאאאאK

٢

-3 -

אאSecondary Relays אאאאאאאK

• אא Electromagnetic Relays

אאאאאאK• אאStatic Relays

א א א (semi-conductors) אא אאאאK

א א אאא(slave devices) אאאאK

• אאMain Relays

אאK• אאאא Back-Up Relays

אאא אא אאאK

• אSelectivity

א FאE אא א א א אאא،אאא

אאאאאאK

٢

-4 -

אSensitivity אאאאאאK• אConsistency

אאאאK• אOperating Time

א א א א אKאאאאא

• אאInstantaneous Relays

א א א א Fא E א١٠K

• אאTime-delay Relay

אאK• אOver Current Relays

א א א אא א אאW

١KאאאאDefinite time-Current Relay

אאאאאאK

٢KאאאאInverse-time-Current Relaysאאאאא

אא( I . t = k) אאK

٢

-5 -

٣KאאאאאInverse-definite time Relay

אאאאאאאK

אFאE

א א אFא Eאאאאאאאא

אאאKא،

אאאאאאאאKא א א א K

אאאאאאאאאאאאא K א א F١ W٢ E٪ א א

אKאאאאאא

אא א אאאא“Electric Brain”Kאאא

אFא Eאאא א א א אא א א א

אאKאאאאאאאא

אאKאאאאאאאאאאאאאאKאאאא

אאא Kאאאאאאאא

אאאאKאW

٢

-6 -

١K אאאאK ٢K אאK ٣K אאאאאאאK ٤K אאאאאK ٥K אאאאאאK

א Fusesאא •• אאא Circuit Breakers • אRelays • אאLightning Arrestors

א אאאאאאא א אא אאא אאא

אאKאאאאא

א א א א א Kאאאאאא

א אFא KEא א א א אאאאאאאאאFאאKE

א א א א א אאאאא

אאK

٢

-7 -

א אאאאאא

אא ، א א א א Fא KE א אא(Distance Relay type reactance)

אאאאאאא א א א אא א א

(Cos Φ)אא )φSin IV

( ٢٪אאאK

א א א א אא אאאא

אא(Potential Transformer) א(Current Transformer)אW

١K א א א א אK

٢K אאאאאאאאאK ٣K אאאאאאK

א אא א אא אא אאא K א א

א אא א א אא א אאא אא

אאאK ( Sensing element)

א( Control element) Kא א א אאאאאאא

אאKאאאאאאאK

אאאאאא

٢

-8 -

אאאאאK

אאאאא(Protective Relays) אאאא

אאאאאאאאאאאאאFאEאא

FאEאאKאF١Eאאאאאאא

K א א א (Bus-Bars) א (Feeders)אאאאKאאאאאK

אאאא אאאא א א אאFא Eאאאא

אאK،אאאאאאאאא

אאאא(Trip Coil t.c.)אא(auxiliary switch)א Kא א א אא

א אKא א א אאאW

אא א א אא א א אא אאאאא Kאאאא

אאאאא א א א א א א

א א א אאאאאK

א אא (L/R)א אאא،אאאאאK

٢

-9 -

אאאא(a)אאאא(rest)Kאאא

אאאאאK

אF١Eאא

محول الجهد

P.T

محول التيارCT

قاطع الدائرة

الدائرة المحمية

اتجاه التشغيل

قضيب التوزيع

قضيب توزيع الثانوي الجهد

ملف تشغيل

مرحل

بطارية

a b c

٢

-01 -

אאאא אאאאא א

אא K אאאא ،א א א א אאאא

א א א K א א אKאWאא

אאאאKאאWאSelectivity

אאאאאאאא אא א א א Kא א א

אא אא אא אא אא KאF٢E

،K

F٢Eאאאאא

א

G G

אא

א

٢

-11 -

אאאאאאאא א א א א K א

אאאאאאK אא FאאEאא א

אאאKא،Kאא( over lapping)א

אK אא אא א

א א א K א F٣ Eא א א א אא F٢ KE א F٣E א א

אאאאאאאMetal clad typeא

אאאאאאאאאאאKאF٤E

אא א Kא אKאאא

אאאאאאאאKא١אאאאא٢

אא٣٤א٥אK

٢

-21 -

F٣Eאאאא

F٤Eאאא

٢

-31 -

אSpeed of operation א אאא،א

אאאאאאאאאאKאא

א א א א א א אאאאK

אאאא א א א א א אא

א א א ،א א،،אאאK

אאאאאאא

א א א א א א א F١}٠١٢}٠EאKאאאא١٥}٠

٣}٠אאאאא٥}١٣אKא א א אאא א

אאאאאאאא،א א

אאאא،אF٠٦}٠١٥}٠E،א٢}٠אא٠٥}٠١٤}٠א

אא١٢}٠א٠٨}٠א ٠٤}٠א א ١}٠ ٢}٠ א

א א ٠٢}٠٠٤}٠א K א א א א

אאאאK

٢

-41 -

א Sensitivity אאאאK

אאאFאאEאאאאKאאאאאאא

א א אא K א א א אאאאא(Back – up protection)K

אReliability א א א א

אאאKא אאאאK

א א א אאאאאאאאא

א א אא א אK אא א א אא Kאאאאאאא

אK

אא Stability א א אא F E

אא אא K אאאאאK

٢

-51 -

אאאאMain and Back-up Protectionאא אא

א אא א א א א אאאאאאאא

א א א K F٤ E אKאא א א א א א אאא

،אאאאאאאW

١K אאאאאK ٢K אאאK ٣K אאאאK ٤K אאאאאK ٥K אאאאאאK