MCQOPTIONS
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MCQOPTIONS
This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Power Systems knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The phasor operator which is used to depict the unbalanced phase voltages into three phase quantities, provides a rotation of |
| A. | 120o counter clockwise |
| B. | 120o clockwise |
| C. | 90o counter clockwise |
| D. | 90o clockwise |
| Answer» B. 120o clockwise | |
| 2. |
A given system to be analysed was found with the below phasor representation of the system voltages. Which of the symmetrical components will be present in the mentioned system? |
| A. | Positive sequence components |
| B. | Negative sequence components |
| C. | Zero sequence components |
| D. | All of the mentioned |
| Answer» B. Negative sequence components | |
| 3. |
A 400 V, 50 Hz three phase balanced source ripples to a star connected load whose rating is S(=300+j400) kVA. A delta connected capacitor bank needed to bring p.f. to 0.9 lagging. The operating power factor of the system is |
| A. | 0.8 |
| B. | 4/3 |
| C. | 3/4 |
| D. | 0.6 |
| Answer» B. 4/3 | |
| 4. |
A 400 V, 50 Hz three phase balanced source ripples to a star connected load whose rating is S(=300+j400) kVA. The rating of the delta connected capacitor bank needed to bring p.f. to 0.9 lagging is _______ KVAR. |
| A. | 254.7 |
| B. | 25.4 |
| C. | 84.9 |
| D. | 284.5 |
| Answer» B. 25.4 | |
| 5. |
Two alternators A and B having 5% speed regulation are working in parallel at a station. Alternator A is rated at 15 MW while B is at 20 MW. When the total load to be shared is 12 MW, then how much of the load will be shared by the alternator B? |
| A. | 6.85 MW |
| B. | 5.14 MW |
| C. | 6 MW |
| D. | 7 MW |
| Answer» B. 5.14 MW | |
| 6. |
A 200 bus power system has 160 PQ bus. For achieving a load flow solution by N-R in polar coordinates, the minimum number of simultaneous equation to be solved is ___________ |
| A. | 359 |
| B. | 329 |
| C. | 360 |
| D. | 320 |
| Answer» B. 329 | |
| 7. |
A three phase transformer has a name plate details of 30 MVA and voltage rating of 230Y kV/69∆ kV with a leakage reactance of 10% and the transformer connection via wye-delta. Taking a base of 230 kV on the high voltage side, the transformer reactance referred to the low voltage side in ohms is |
| A. | 0.1 |
| B. | 0.2 |
| C. | 0.198 |
| D. | 0.4 |
| Answer» B. 0.2 | |
| 8. |
A three phase transformer has a name plate details of 30 MVA and voltage rating of 230Y kV/69∆ kV with a leakage reactance of 10% and the transformer connection via wye-delta. Taking a base of 230 kV on the high voltage side, the transformer reactance referred to the low voltage side in ohms is __________ |
| A. | 47.61 Ω |
| B. | 15.87 Ω |
| C. | 176.33 Ω |
| D. | 157.8 Ω |
| Answer» B. 15.87 Ω | |
| 9. |
A three phase transformer has a name plate details of 30 MVA and voltage rating of 230Y kV/69∆ kV with a leakage reactance of 10% and the transformer connection via wye-delta. Taking a base of 230 kV on the high voltage side, the transformer reactance on the LV side is___________ |
| A. | 176.33 Ω |
| B. | 1763.3 Ω |
| C. | 47.6 Ω |
| D. | 15.87 Ω |
| Answer» B. 1763.3 Ω | |
| 10. |
A three phase transformer has a name plate details of 30 MVA and voltage rating of 230Y kV/69∆ kV with a leakage reactance of 10% and the transformer connection via wye-delta. Taking a base of 230 kV on the high voltage side, turns ratio of the windings is ______ |
| A. | 2 |
| B. | 1.5 |
| C. | 6 |
| D. | 4 |
| Answer» B. 1.5 | |