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الموضوع: ملتقى الخبراء

  1. #1
    عضو رابطة مهندسى الكهرباء العرب الصورة الرمزية رافد الشاوي
    تاريخ التسجيل
    May 2006
    الدولة
    iraq
    المشاركات
    440

    ملتقى الخبراء

    الى كافة الاخوان المهندسين الذين لديهم خبرة في موضوع مناول المسافة ان يضع معلومة ولو بسيطة عن مناول المسافة لكي يصبح عبارة عن مصدر لهذا الموضوع لاخوان الذين لديهم اسئلة عن هذاالموضوع المهم

    شاكر استجابتكم

  2. #2
    عضو مجلس إدارة المنتديات
    تاريخ التسجيل
    Sep 2006
    الدولة
    Ciro
    المشاركات
    277

    رد: ملتقى الخبراء

    السلام عليكم ورحمة الله وبركاته
    أخوانى الأعزاء
    سوف أعطى فكرة مبسطة عن أهم وقاية للخطوط والكابلات وخاصة لمهمات الجهد الفائق والعالى (500-220-66) كيلو فولت - وهى Distance Relay

    - فكرة عمل الجهاز:
    1- يتم أولا وضع قيم ال Primary Data للخط أو الكابل (من طوله بالكيلو متر- مساحة مقطعه-نوع مادته) ويتم تحديد حسابات قيم الSecondary التى سوف توضع على الجهاز
    طبقا ل )Current Transformer Ratio
    Voltage Transformer Ratio,ومن هذه النسبة ومعلومية Z primary للمراحل وهى : Z1 primary,Z2 primary ,Z3 primary,Z4 primary
    وكذلك قيم Fault Angle ,Ko
    من هذه القيم يتم حسابات Z1,Z2,Z3,Z4 Secondary التى توقع على الجهاز
    ويعتمد أساسا على قيم X,R والتى منها يرسم الCharachtristic التى يعمل عليها الجهاز ويتحقق من قيم الضبط من خلال أجهزة ال Tester والخاصة لكل نوعية من منتجات الشركات.
    وتكون عادة Z1 =80%
    Z2 = 100%
    Z3 = 120%
    Z4 = Revirse Direction
    - ويراعى عند توصيل أطراف الجهاز : أتجاه تأريض الجهاز
    - أتجاه تأريض محولات التيار للدائرة( Bus Bar side or Line side)
    حتى يعمل الجهاز فى الإتجاه الصحيح وهو- يرى الFault بأتجاه الجهة لأخرى
    - وفى الجهة الأخرى من الخط (المحطة المقابلة)- يفضل أن يكون الجهاز المركب من نفس الطراز وبنفس القيم حتى يتحقق تحديد سليم للFault
    - يعمل الجهاز لتحديد جميع أنواع القصر (Phase to Phase & Phase to Earth)
    وهناك Timrs تعمل مع هذة النوعيات من القصر وتحددها المراحل .
    مكونات الجهاز : (Sensing Element -Measuring Element -Action Element)
    هذة فكرة مبسطة أرجوا أن أكون قد قدمت بها ولو معلومة .

    أخيكم / Mohamed Gamal Edeen

  3. #3
    عضو رابطة مهندسى الكهرباء العرب الصورة الرمزية رافد الشاوي
    تاريخ التسجيل
    May 2006
    الدولة
    iraq
    المشاركات
    440

    رد: ملتقى الخبراء

    اجدد دعوتي الى الاخوان المهندسين
    وهذ مثال تطبيقي لمعايرة مناول مسافة نوع alstom p442
    الملفات المرفقة الملفات المرفقة

  4. #4
    عضو رابطة مهندسى الكهرباء العرب الصورة الرمزية رافد الشاوي
    تاريخ التسجيل
    May 2006
    الدولة
    iraq
    المشاركات
    440

    رد: ملتقى الخبراء

    اجدد دعوتي الى الاخوان المهندسين المختصين في هذا المجال اغناء الموضوع بالمعلومات الرائعة

  5. #5
    Junior Engineer
    تاريخ التسجيل
    May 2006
    الدولة
    KSA
    المشاركات
    102

    رد: ملتقى الخبراء

    هذاه طريقة حساب قيم الضبط لمرحل من نوع Siemens 7SA522



    RELAY SETTING FOR DISTANCRE PROTECTION RELAY 21DP

    GENERAL PROJECT DATA:

    CUSTOMER:
    PROJECT: 380KV S/S
    STATION:
    FEEDER:

    DISATNCE PROTECTION RELAY TYPE 7SA522
    Power System Data:

    System voltage 380 kV
    Frequency f 60 Hz
    System time contant 80 ms
    Short Circuit Level on 380Kv Bus Bar 50 KA

    Instrument Transformers:

    CT ratio:
    Primary 2000 Amp
    Secondary 1 Amp
    PT ratio:
    Primary 380000 Volts
    Secondary 100 Volts

    Impedance transformation Factor:

    nCT ratio/n PT ratio = 0.53 =K

    Line Parameters:
    Line length = 98 km
    Positive sequence resistance R1 = 0.0185 Ohm/km/phase
    Positive sequence reactance X1 = 0.352 Ohm/km/phase
    Zero sequence resistance Ro = 0.231 Ohm/km/phase
    Zero sequence reactance Xo = 1.223 Ohm/km/phase
    Mutual Zero sequence resistance R0M = 0.1386 Ohm/km/phase
    Mutual Zero sequence reactance X0M = 0.07338 Ohm/km/phase
    Secondary values of the protected line:

    R1= Line length * R1 * K = 0.96 Ohms
    X1 = Line length * X1 * K = 18.28 Ohms
    Ro = Line length * Ro * K = 12.00 Ohms
    Xo = Line length * Xo * K = 63.52 Ohms

    Mutual Zero sequence resistance R0M = 7.20
    Mutual Zero sequence reactance X0M = 38.112

    Next Shortest line is
    L = 12
    R1 = 0.0185
    X1 = 0.352
    Ro = 0.44
    Xo = 1.67
    Secondary Parameters of Next Shortest Lines:

    R1( shortest line ) = 0.120 Ohm/phase
    X1 ( shortest line ) = 2.240 Ohm/phase
    Ro( shortest line ) = 2.800 Ohm/phase
    Xo ( shortest line ) = 10.620 Ohm/phase

    Next Longest Line is:
    L = 63.7
    R1 = 0.0185
    X1 = 0.352
    Ro = 0.44
    Xo = 1.67
    Secondary Parameters of Next Longest Lines:
    R1( longest line ) = 0.620 Ohm/phase
    X1 ( longest line ) = 11.880 Ohm/phase
    Ro( longest line ) = 14.850 Ohm/phase
    Xo ( longest line ) = 56.380 Ohm/phase

    Max. current carrying capacity of F/D = 2500 Amps
    Maximum load on feeder Pmax1 = 1.73*System Voltage*Max. current
    Maximum load on feeder Pmax1 = 1645 MVA (Continuous Duty)
    Maximum Overload on feeder Pmax2 = 1.0*Max. load on Feeder (assumed)
    Maximum Overload on feeder Pmax2 = 1645 MVA

    Minimum Load Impedance:
    The minimum load impedance can be calculated on the basis of a maximum permitted power flow over
    the protected feeder. We suppose also 90% of rated voltage as a minimum permitted system voltage.
    We also suppose the minimum load factor of 90%. This gives the minimum
    load impedance of :

    Umin = 0.9Un
    Rloadmin(Primary) = ( Umin)^2 / Pmax = 78.98 Ohms
    Rloadmin(Secondary) = Umin / 1.73* Ilmax = K*78.98
    Rloadmin(Secondary) = Umin / 1.73* Ilmax = 41.86 Ohms
    Applying a margin of 10%
    Rloadmin(Secondary) = 37.674 Ohms

    System p.f = 0.63
    Load Angle = cos-1(0.63)
    = 51
    Taking a margin of 5o due to load spread angle
    Setting f load(q-E) = 56 deg

    Z1 = R1+ j X1 = 0.96 + j 18.28
    = 18.31 Ohms
    Short Circuit angle = 86.99 degree

    Zo = Ro+ j Xo = 12.00 + j 63.52
    = 64.64 Ohms
    angle = 79.3 degree


    SETTINGS FOR EARTH IMPEDANCE RATIO:

    Resistance Ratio:
    RG/RL = 1/3(Ro/R1-1)
    = 3.83

    Reactance Ratio:
    XG/XL = 1/3(Xo/X1-1)
    = 0.82


    PHILOSIPHY OF CALCULATION AND RELAY SETTING:

    ZONE REACH SETTINGS :
    Zone 1: 85% of the line
    Zone 1B: 200% of the line
    Zone 2: 100% of (Protected line+ 50% Next shortest line)
    Zone 3: 100% of (Protected line+Next longest line)
    Zone 4: 200% * Z3
    Zone 5: 300% * Z4


    SETTINGS FOR MUTUAL PARALLEL LINE COMPENSATION RATIO:

    Resistance Ratio:
    RM/RL = 1/3(R0M/RL)
    = 2.50

    Reactance Ratio:
    XM/XL = 1/3(X0M/XL)
    = 0.07


    Resistive reach Philosiphy
    The following formula are used to calculate the arc resistance

    For Zone-1:
    It may be assumed that the arc voltage is independent of the current magnitude
    Hence as a standard we can use:
    Uarc = 2500 V/m
    From this, arc-resistance is:
    Rarc = 2500*Larc/ Iarc ohms- - - - - - - - - - - - - - - - - - - - - - - - - - - - - (equation-1)
    Where,
    Iarc = arc current in A
    Larc = arc length in meters

    Rarc = 28700*Larc / ( Iarc )^1.4- - - - - - - - - - - - - - (equation-2)
    Larc = 4 meter (assumed)
    I = 1 kA (assumed)
    => Rarc = 7.25 Ohms Pri.
    For Higher Zones:
    The arc may expands due to wind and delay ed time. This is the dynamics of the arc.
    The following equation represents an approximationof this phenomena:
    Rarc* = (1+(5*v*tB/Larc)).Rarc- - - - - - - - - - - - - - (equation-3)
    tB = arc duration in s
    v = wind velocity in m/s
    Larc = Original Length of arc
    hence,
    Iph-E = 5000 A
    Iph-ph = 5000 A
    ZONE-1 SETTING
    X-Setting:
    X(Z1) = 0.85*Line Length*K*X1
    = 0.85*98*0.53*0.352
    = 15.54 ohms

    Resistive Reach:
    Tower Footing Resistance(primary) = 10 ohms
    Tower Footing Resistance(Secondary),RT = 5.3 ohms

    From equation -1
    Rarc(ph-ph) = 2500*4/5000
    = 2 ohms(primary)
    = 1.06 ohms(secondary)
    & From equation-2
    Rarc(ph-ph) = 28700*4/(5000)^1.4
    = 0.76 ohms(primary)
    = 0.4 ohms(secondary)
    Hence , as a worst case we can use higher of the two values
    Rarc(ph-ph) = 1.06 ohms
    For phase -E fault
    From equation -1
    Rarc(ph-E) = 2500*4/5000
    = 2 ohms(primary)
    = 1.06 ohms(secondary)
    & From equation-2
    Rarc(ph-E) = 28700*4/(5000)^1.4
    = 0.76 ohms(primary)
    = 0.4 ohms(secondary)
    Hence , as a worst case we can use higher of the two values
    Rarc(ph-E) = 1.06 ohms
    R-Setting:
    As we have to give adequate margin for the arc resistance but this value sould not exceed six times the
    value of X setting for the Zone in consideration. Hence , this can be calculated as:

    R(Z1) = 0.85* Line Length*K*R1 +0.5*Rarc(ph-ph)
    = 0.85*98*0.53*0.0185 +0.5*1.06
    = 1.35 ohms
    Now, for earth fault arc resistance shall include tower footing resistance.
    RG(Z1) = 0.85* Line Length*Kimp*R1 +Rarc(ph-E)+RT
    0.85*98*0.53*0.0185 +1.06+5.3
    = 7.18


    ZONE-2 SETTING
    X-Setting:
    X(Z2) = 1*(X1 Protected Line + 0.5 * X1 Next Shortest Line) >1.2*X1L*K
    = 1*(18.28+0.5*2.24)
    = 19.40 ohms > 21.94
    Hence, our Setting is = 21.94 ohms

    Resistive Reach:
    We can use equation -3 to calculate the arc resistance for this zone
    We can have
    v = 3 m/s
    tB2 = 0.60 s

    Rarc*(ph-ph) = (1+(5*3*0.6/4))*1.06
    = 3.45 ohms
    Also,
    Rarc*(ph-E) = (1+(5*3*0.6/4))*1.06
    = 3.45 ohms

    R-Setting:
    As we have to give adequate margin for the arc resistance but this value sould not exceed six times the
    value of X setting for the Zone in consideration. Hence , this can be calculated as:

    R(Z2) = 1*(R1 Protected Line + 0.5 * R1 Next Shortest Line) +0.5*Rarc(ph-ph)
    = 1*(0.96+0.5*0.12) +0.5*3.45
    = 2.75 ohms
    Now, for earth fault arc resistance shall include tower footing resistance.
    RG(Z2) = 1*(R1 Protected Line + 0.5 * R1 Next Shortest Line) +Rarc(ph-E)+RT
    = 1*(0.96+0.5*0.12) +3.45+5.3
    = 9.77

    ZONE-3 SETTINGS:
    X-Setting:
    X(Z3) = 1*(X1 Protected Line + X1 Next Longest Line)
    = 1*(18.28+11.88)
    = 30.16 ohms

    Resistive Reach:
    We can use equation -3 to calculate the arc resistance for this zone
    We can have
    v = 3 m/s
    tB3 = 1.00 s

    Rarc*(ph-ph) = (1+(5*3*1/4))*1.06
    = 5.04 ohms
    &
    Rarc*(ph-E) = (1+(5*3*1/4))*1.06
    = 5.04 ohms

    R-Setting:
    As we have to give adequate margin for the arc resistance but this value sould not exceed six times the
    value of X setting for the Zone in consideration. Hence , this can be calculated as:

    R(Z3) = 1*(R1 Protected Line + R1 Next Longest Line) +0.5*Rarc(ph-ph)
    = 1*(0.96+0.62) +0.5*5.04
    = 4.10 ohms
    Now, for earth fault arc resistance shall include tower footing resistance.


    RG(Z3) = 1*(R1 Protected Line + R1 Next Longest Line) +Rarc(ph-E)+RT
    1*(0.96+0.62) +5.04+5.3
    = 11.92 ohms

    X-Setting:
    X(Z4) = 2*(1*(X1 Protected Line + X1 Next Longest Line))
    = 2*(1*(18.28+11.88))
    = 60.32 ohms

    Resistive Reach:
    We can use equation -3 to calculate the arc resistance for this zone
    We can have
    v = 3 m/s
    tB4 = 1.50 s

    Rarc*(ph-ph) = (1+(5*3*1.5/4))*1.06
    = 7.02 ohms
    &
    Rarc*(ph-E) = (1+(5*3*1.5/4))*1.06
    = 7.02 ohms
    R-Setting:
    As we have to give adequate margin for the arc resistance but this value sould not exceed six times the
    value of X setting for the Zone in consideration. Hence , this can be calculated as:

    R(Z4) = 2*(1*(R1 Protected Line + R1 Next Longest Line) +0.5*Rarc(ph-ph))
    = 2*(1*(0.96+0.62)) +0.5*7.02
    = 6.67 ohms
    Now, for earth fault arc resistance shall include tower footing resistance.


    RG(Z4) = 2*(1*(R1 Protected Line + R1 Next Longest Line) +Rarc(ph-E)+RT
    2*(1*(0.96+0.62)) +7.02+5.3
    = 15.48 ohms

    ZONE-5 SETTINGS:
    X-Setting:
    X(Z5) = 3*(2*(1*(X1 Protected Line + X1 Next Longest Line)))
    = 3*(2*(1*(18.28+11.88)))
    = 180.96 ohms

    Resistive Reach
    We can use equation -3 to calculate the arc resistance for this zone
    We can have
    v = 3 m/s
    tB5 = 2.00 s

    Rarc*(ph-ph) = (1+(5*3*2/4))*1.06
    = 9.01 ohms
    Rarc*(ph-E) = (1+(5*3*2/4))*1.06
    = 9.01 ohms
    R-Setting:
    As we have to give adequate margin for the arc resistance but this value sould not exceed six times the
    value of X setting for the Zone in consideration. Hence , this can be calculated as:

    R(Z5) = 3*(2*(1*(R1 Protected Line + R1 Next Longest Line) +0.5*Rarc(ph-ph))
    = 3*(2*(1*(0.96+0.62))) +0.5*9.01
    = 13.99 ohms
    Now, for earth fault arc resistance shall include tower footing resistance.


    RG(Z5) = 3*(2*(1*(R1 Protected Line + R1 Next Longest Line) +Rarc(ph-E)+RT
    3*(2*(1*(0.96+0.62))) +9.01+5.3
    = 23.79 ohms
    ZONE-1B (OVERREACHING ) SETTINGS:
    This zone should start positively for any fault in the forward direction of
    the protected line. We propose a setting of :

    X-Setting:
    X(Z1B) = 2*Line Length*Kimp*X1
    = #REF!
    = 36.56 ohms

    Resistive Reach:
    We can use equation -3 to calculate the arc resistance for this zone
    We can have
    v = 3 m/s
    tB1B = 0.00 s

    Rarc*(ph-ph) = (1+(5*3*0/4))*1.06
    = 1.06 ohms
    &
    Rarc*(ph-E) = (1+(5*3*0/4))*1.06
    = 1.06 ohms

    R-Setting:
    As we have to give adequate margin for the arc resistance but this value sould not exceed six times the
    value of X setting for the Zone in consideration. Hence , this can be calculated as:

    R(Z1B) = 2* Line Length*Kimp*R1 +0.5*Rarc(ph-ph)
    = 2*98*0.53*0.0185 +0.5*1.06
    = 2.45 ohms
    Now, for earth fault arc resistance shall include tower footing resistance.
    RG(Z1B) = 2* Line Length*Kimp*R1 +Rarc(ph-E)+RT
    2*98*0.53*0.0185 +1.06+5.3
    = 8.28 ohms



    SETTINGS FOR EMERGENCY OVERCURRENT PROTECTION:


    I> = 2.5 *In
    = 2.5 A
    TI> = 2.5 sec.
    3Io> = 0.4 *In
    = 0.4
    = 0.4 A
    T3Io> = 2.5 sec.
    I>> = 2.5 *In
    = 2.5 A
    TI>> = 2.5 sec.


    SETTINGS FOR DIRECTIONAL EARTH FAULT PROTECTION:

    Scheme Selected DIRCTIONAL COMPARISON
    3Io > = 0.1 *In
    = 0.1 A
    T 3Io > = 0.15 sec.
    3Io >> = 0.7 *In
    = 0.7 A
    T 3Io >> = 2.00 sec.
    3Uo > = 5 V
    Note:
    Remaining all stages shall be blocked .

    TELEPROTECTION SCHEME:

    SCHEME = POTT(With Z1B tripping and sending also)


    LOAD ENCROACHMENT CHECK:

    The value of resistive reach setting for zone - 5 is :
    R5= R5E = 23.79 ohms
    Rloadmin(Secondary) = Umin / 1.73* Ilmax = 37.674 ohms

    Hence there is no possibility of load encroachment.

    TIMER SETTINGS:

    T1 = 0.00 sec.
    T2 = 0.60 sec.
    T3 = 1.00 sec.
    T4 = 1.50 sec.
    T5 = 2.00 sec.

  6. #6
    عضو رابطة مهندسى الكهرباء العرب الصورة الرمزية رافد الشاوي
    تاريخ التسجيل
    May 2006
    الدولة
    iraq
    المشاركات
    440

    رد: ملتقى الخبراء

    الاخوان المهندسن احب ان اظيف هذا الملف البسيط
    الملفات المرفقة الملفات المرفقة

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