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A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.
Correct answer is between '15300.00,15500.00'. Can you explain this answer?
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Verified Answer
A three phase, 100 MVA, 25kV generator has solidly grounded neutral. T...
Concept:
In a single line to ground (LG) fault, the fault current is
Where,
Ea = terminal voltage
Z1 = positive sequence impedance
Z2 = negative sequence impedance
Z0 = zero sequence impedance
Zn = impedance in neutral grounding
The fault current can also be written as If = 3Ia1
In a single line to ground (LG) fault, the fault current is
Where,
Ea = terminal voltage
Z1 = positive sequence impedance
Z2 = negative sequence impedance
Z0 = zero sequence impedance
Zn = impedance in neutral grounding
The fault current can also be written as If = 3Ia1
Calculation:
Single line to ground fault, Fault current in If = 3Ia1
Fault current If = 15396 A.
Single line to ground fault, Fault current in If = 3Ia1
Fault current If = 15396 A.
Most Upvoted Answer
A three phase, 100 MVA, 25kV generator has solidly grounded neutral. T...
Concept:
In a single line to ground (LG) fault, the fault current is
Where,
Ea = terminal voltage
Z1 = positive sequence impedance
Z2 = negative sequence impedance
Z0 = zero sequence impedance
Zn = impedance in neutral grounding
The fault current can also be written as If = 3Ia1
In a single line to ground (LG) fault, the fault current is
Where,
Ea = terminal voltage
Z1 = positive sequence impedance
Z2 = negative sequence impedance
Z0 = zero sequence impedance
Zn = impedance in neutral grounding
The fault current can also be written as If = 3Ia1
Calculation:
Single line to ground fault, Fault current in If = 3Ia1
Fault current If = 15396 A.
Single line to ground fault, Fault current in If = 3Ia1
Fault current If = 15396 A.
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Community Answer
A three phase, 100 MVA, 25kV generator has solidly grounded neutral. T...
Given information:
- Generator rating: 100 MVA
- Line voltage: 25 kV
- Neutral grounding: Solidly grounded
- Positive sequence reactance: 0.2 pu
- Negative sequence reactance: 0.2 pu
- Zero sequence reactance: 0.05 pu
Calculating fault current:
1. Calculate the per unit impedance of the generator:
- The per unit impedance is calculated by dividing the reactance by the base impedance.
- Given the generator rating is 100 MVA, we need to calculate the base impedance.
- The base impedance is calculated using the formula: \(Z_{base} = \dfrac{V_{base}^2}{S_{base}}\), where \(V_{base}\) is the line voltage and \(S_{base}\) is the generator rating.
- Substituting the given values, we get \(Z_{base} = \dfrac{25^2 \times 10^3}{100 \times 10^6} = 0.625 \Omega\).
- The positive sequence impedance is 0.2 pu, which is equal to \(0.2 \times 0.625 = 0.125 \Omega\) in absolute terms.
2. Calculate the fault current:
- In a solidly grounded system, the fault current is given by \(I_f = \dfrac{V_f}{Z_{pos}}\), where \(V_f\) is the fault voltage and \(Z_{pos}\) is the positive sequence impedance.
- The fault voltage is the line voltage, which is 25 kV or 25,000 volts.
- Substituting the values, we get \(I_f = \dfrac{25,000}{0.125} = 200,000\) amperes.
3. Convert the fault current to amperes:
- The fault current is given in per unit, so we need to convert it to amperes.
- The base current is calculated using the formula: \(I_{base} = \dfrac{S_{base}}{V_{base}}\), where \(I_{base}\) is the base current.
- Substituting the given values, we get \(I_{base} = \dfrac{100 \times 10^6}{25 \times 10^3} = 4,000\) amperes.
- The fault current in amperes is calculated by multiplying the per unit fault current by the base current.
- Substituting the values, we get \(I_{fault} = 200,000 \times 4,000 = 800\) million amperes or 80,000 amperes.
Conclusion:
The fault current in amperes immediately after the fault is approximately 80,000 amperes.
- Generator rating: 100 MVA
- Line voltage: 25 kV
- Neutral grounding: Solidly grounded
- Positive sequence reactance: 0.2 pu
- Negative sequence reactance: 0.2 pu
- Zero sequence reactance: 0.05 pu
Calculating fault current:
1. Calculate the per unit impedance of the generator:
- The per unit impedance is calculated by dividing the reactance by the base impedance.
- Given the generator rating is 100 MVA, we need to calculate the base impedance.
- The base impedance is calculated using the formula: \(Z_{base} = \dfrac{V_{base}^2}{S_{base}}\), where \(V_{base}\) is the line voltage and \(S_{base}\) is the generator rating.
- Substituting the given values, we get \(Z_{base} = \dfrac{25^2 \times 10^3}{100 \times 10^6} = 0.625 \Omega\).
- The positive sequence impedance is 0.2 pu, which is equal to \(0.2 \times 0.625 = 0.125 \Omega\) in absolute terms.
2. Calculate the fault current:
- In a solidly grounded system, the fault current is given by \(I_f = \dfrac{V_f}{Z_{pos}}\), where \(V_f\) is the fault voltage and \(Z_{pos}\) is the positive sequence impedance.
- The fault voltage is the line voltage, which is 25 kV or 25,000 volts.
- Substituting the values, we get \(I_f = \dfrac{25,000}{0.125} = 200,000\) amperes.
3. Convert the fault current to amperes:
- The fault current is given in per unit, so we need to convert it to amperes.
- The base current is calculated using the formula: \(I_{base} = \dfrac{S_{base}}{V_{base}}\), where \(I_{base}\) is the base current.
- Substituting the given values, we get \(I_{base} = \dfrac{100 \times 10^6}{25 \times 10^3} = 4,000\) amperes.
- The fault current in amperes is calculated by multiplying the per unit fault current by the base current.
- Substituting the values, we get \(I_{fault} = 200,000 \times 4,000 = 800\) million amperes or 80,000 amperes.
Conclusion:
The fault current in amperes immediately after the fault is approximately 80,000 amperes.
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A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer?
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A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer?.
A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer?.
Solutions for A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? in English & in Hindi are available as part of our courses for Electrical Engineering (EE).
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A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer?, a detailed solution for A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? has been provided alongside types of A three phase, 100 MVA, 25kV generator has solidly grounded neutral. The positive, negative, and the zero sequence reactances of the generator are 0.2 pu, 0.2 pu, and 0.05 pu, respectively, at the machine base quantities. If a bolted single phase to ground fault occurs at the terminal of the unloaded generator, the fault current in amperes immediately after the fault is________.Correct answer is between '15300.00,15500.00'. Can you explain this answer? theory, EduRev gives you an
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