AKTU Power System-I · Important Questions 2026Source: ryzenstudy.com PYQs
BEE501 Power System-I Important Questions 2026 (AKTU)
Repeat analysis + most-asked questions, unit-wise
What we did: built from all 4 AKTU Power System-I papers (2021-22–2024-25): 97 questions grouped into 62 distinct questions, 21 of which were asked in more than one paper.
- of marks were repeat questions
- 58%
- of marks were repeat questions
- questions asked in 2+ papers
- 21
- questions asked in 2+ papers
- papers analysed (2021-22–2024-25)
- 4
- papers analysed (2021-22–2024-25)
- units, mapped to current syllabus
- 5
- units, mapped to current syllabus
How much of the paper repeats?
- Repeats are real: when we checked each newer BEE501 paper against the papers before it, on average 58% of its marks were questions already asked in an earlier paper.
- 2023-24 paper: 41% of marks were repeats (5 of 11 repeated questions were in our top list).
- 2024-25 paper: 75% of marks were repeats (11 of 17 repeated questions were in our top list).
- Topic weightage is a guide, not a guarantee: our Tier 1 + Tier 2 topics covered 63% of the next paper's marks — picking the same number of topics at random would have covered about 53%.
Across 10 subjects and 23 papers we tested, 43% of marks repeated earlier questions on average.
1.Unit-wise most-asked questions
Ranked by how many papers asked them, then by how recently. Click a paper to open it.
Unit 1: (Power Generation)
20% of past marks| Question | Asked |
|---|---|
| The yearly load duration curve of a power plant is a straight line. The maximum load is 500 MW and the minimum load is 400 MW. The capacity of the plant is 750 MW. Find (a) Plant capacity factor (b) Load factor (c) Utilization factor (d) Reserve capacity. | Asked 3× |
| Describe the renewable and non-renewable energy resources. | Asked 3× |
| Define these terms: (i) Demand Factor (ii) Diversity Factor. | Asked 3× |
| Draw the block diagram and explain the working of thermal power plants. | Asked 2× |
Unit 2: Configurations of transmission lines · Performance of Lines
22% of past marks| Question | Asked |
|---|---|
| Sketch the T and pi model of medium transmission lines and explain their parameters. | Asked 3× |
| What are corona effects? Explain the factors which affect the corona loss and how it is reduced. | Asked 2× |
| Compare the volume of conductor material required for a d.c. 3-wire system and 3-phase, 3-wire system on the basis of equal maximum potential difference between one conductor and earth. Make suitable assumptions. | Asked 2× |
| What do you understand by single line diagram in power system? | Asked 2× |
Unit 3:
21% of past marks| Question | Asked |
|---|---|
| Describe the factors affecting sag of an overhead transmission line. | Asked 3× |
| Each conductor of a three-phase overhead line is suspended from a cross arm of a steel tower by a string of 4 suspension insulators. The voltage across the second unit is 14.2 KV and across the third 20 KV. Find the voltage between the conductors and the string efficiency. | Asked 2× |
| Explain the methods of calculating sag and tension of overhead transmission lines at unequal level of ground. | Asked 2× |
| Define the term sag. | Asked 2× |
Unit 4: (Transmission Line Parameters)
17% of past marks| Question | Asked |
|---|---|
| What do you mean by self GMD and mutual GMD? | Asked 3× |
| A three phase 50 Hz line consists of three conductors each of diameter 21 mm. The spacing between the conductors is as follows (see original paper). Find the inductance and inductive reactance per phase per km of the line. | Asked 2× |
| Derive an expression for the capacitance of a symmetrical three phase line. | Asked 2× |
| Derive an expression for the inductance of a symmetrical three phase line. What is meant by the term equivalent spacing? State its significance. 7 marks2024-25 Q6(b) | Asked 1× |
Unit 5: (Insulated Cables)
20% of past marks| Question | Asked |
|---|---|
| Determine the overall diameter of a single core cable and its most economical diameter when working on a 3 phase 275 KV system. The maximum permissible stress in the dielectric is not to exceed 15 KV/ (see original paper). | Asked 3× |
| Explain the term insulation and also explain the types of insulating materials. | Asked 3× |
| Explain in detail grading of the overhead cables. | Asked 2× |
| Discuss the inter-sheath grading of cables. What are the practical difficulties in the grading of cables? | Asked 2× |
2.Topic weightage: which topics carry the marks
Blue = Tier 1 + Tier 2 (topics that carried ~80% of past marks). Grey = the rest. It shows where marks have gone, not a promise of what comes next.
Load curve and load factors · U1
10.6% (cum 11%)
Grading of cables · U5
10.1% (cum 21%)
Sag and tension calculation · U3
6.9% (cum 28%)
Short and medium transmission lines · U2
5.5% (cum 33%)
Corona effect · U2
5.1% (cum 38%)
Hydro, thermal, nuclear plant layouts · U1
5.1% (cum 43%)
String potential distribution and efficiency · U3
4.8% (cum 48%)
Capacitance of single and three phase lines · U4
4.3% (cum 52%)
Types and construction of cables · U5
3.9% (cum 56%)
Cable insulation and insulating materials · U5
3.8% (cum 60%)
Conductors, skin effect, Kelvin law · U2
3.8% (cum 64%)
Transposition · U4
3.7% (cum 68%)
Composite conductors and GMD · U4
3.3% (cum 71%)
Supply systems and distribution · U2
3% (cum 74%)
Single line diagram and per unit system · U2
2.9% (cum 77%)
Conventional and non-conventional sources · U1
2.9% (cum 80%)
Types of insulators · U3
2.7% (cum 82%)
Wind and ice loading · U3
2.6% (cum 85%)
Inductance of single and three phase lines · U4
2.6% (cum 88%)
Overhead lines versus underground cables · U5
2.2% (cum 90%)
Bundled conductors · U4
2.1% (cum 92%)
Sag template and vibration dampers · U3
1.9% (cum 94%)
Long lines, ABCD constants, Ferranti effect · U2
1.7% (cum 96%)
Smart grid and IT components · U1
1.5% (cum 97%)
Catenary curve · U3
1.2% (cum 98%)
Methods of equalizing string potential · U3
1.2% (cum 99%)
Effect of earth on capacitance · U4
0.5% (cum 100%)
| Topic | Papers | Share |
|---|---|---|
| Load curve and load factors · Unit 1 · Tier 1 | 4/4 | 10.6% |
| Grading of cables · Unit 5 · Tier 1 | 4/4 | 10.1% |
| Sag and tension calculation · Unit 3 · Tier 1 | 4/4 | 6.9% |
| Short and medium transmission lines · Unit 2 · Tier 1 | 4/4 | 5.5% |
| Corona effect · Unit 2 · Tier 1 | 3/4 | 5.1% |
| Hydro, thermal, nuclear plant layouts · Unit 1 · Tier 1 | 3/4 | 5.1% |
| String potential distribution and efficiency · Unit 3 · Tier 1 | 4/4 | 4.8% |
| Capacitance of single and three phase lines · Unit 4 · Tier 1 | 3/4 | 4.3% |
| Types and construction of cables · Unit 5 · Tier 2 | 3/4 | 3.9% |
| Cable insulation and insulating materials · Unit 5 · Tier 2 | 4/4 | 3.8% |
| Conductors, skin effect, Kelvin law · Unit 2 · Tier 2 | 2/4 | 3.8% |
| Transposition · Unit 4 · Tier 2 | 2/4 | 3.7% |
| Composite conductors and GMD · Unit 4 · Tier 2 | 3/4 | 3.3% |
| Supply systems and distribution · Unit 2 · Tier 2 | 3/4 | 3% |
| Single line diagram and per unit system · Unit 2 · Tier 2 | 2/4 | 2.9% |
| Conventional and non-conventional sources · Unit 1 · Tier 2 | 3/4 | 2.9% |
| Types of insulators · Unit 3 · Tier 2 | 2/4 | 2.7% |
| Wind and ice loading · Unit 3 · Tier 3 | 1/4 | 2.6% |
| Inductance of single and three phase lines · Unit 4 · Tier 3 | 2/4 | 2.6% |
| Overhead lines versus underground cables · Unit 5 · Tier 3 | 2/4 | 2.2% |
| Bundled conductors · Unit 4 · Tier 3 | 1/4 | 2.1% |
| Sag template and vibration dampers · Unit 3 · Tier 3 | 2/4 | 1.9% |
| Long lines, ABCD constants, Ferranti effect · Unit 2 · Tier 3 | 2/4 | 1.7% |
| Smart grid and IT components · Unit 1 · Tier 3 | 1/4 | 1.5% |
| Catenary curve · Unit 3 · Tier 3 | 1/4 | 1.2% |
| Methods of equalizing string potential · Unit 3 · Tier 3 | 1/4 | 1.2% |
| Effect of earth on capacitance · Unit 4 · Tier 3 | 1/4 | 0.5% |
3.Paper pattern (2024-25)
| Section | Questions | Rule |
|---|---|---|
| A | 7 × 2 marks | Attempt all |
| B | 5 × 7 marks | Attempt any 3 |
| C | 10 × 7 marks | Attempt any 1 |
4.In the syllabus, never asked yet
Low priority, but read them once — a new paper can always start here.
- Cogeneration, captive and solar PV · U1
- Base load and peak load sharing · U1
- Line conductors and inductance basics · U4
- EHV cables · U5
- Cable insulation resistance and capacitance · U5
5.Study order
- 1Load curve and load factors (Unit 1, Tier 1)
- 2Grading of cables (Unit 5, Tier 1)
- 3Sag and tension calculation (Unit 3, Tier 1)
- 4Short and medium transmission lines (Unit 2, Tier 1)
- 5Corona effect (Unit 2, Tier 1)
- 6Hydro, thermal, nuclear plant layouts (Unit 1, Tier 1)
- 7String potential distribution and efficiency (Unit 3, Tier 1)
- 8Capacitance of single and three phase lines (Unit 4, Tier 1)
- 9Types and construction of cables (Unit 5, Tier 2)
- 10Cable insulation and insulating materials (Unit 5, Tier 2)
- 11Conductors, skin effect, Kelvin law (Unit 2, Tier 2)
- 12Transposition (Unit 4, Tier 2)
- 13Composite conductors and GMD (Unit 4, Tier 2)
- 14Supply systems and distribution (Unit 2, Tier 2)
- 15Single line diagram and per unit system (Unit 2, Tier 2)
- 16Conventional and non-conventional sources (Unit 1, Tier 2)
- 17Types of insulators (Unit 3, Tier 2)
FAQ
Which units of BEE501 carry the most marks?
Unit 2 (Configurations of transmission lines · Performance of Lines, 22% of past marks) and Unit 3 (, 21% of past marks).
Do AKTU Power System-I questions repeat?
Yes. On average 58% of the marks in each newer BEE501 paper came from questions already asked in an earlier paper, and 21 questions have appeared in more than one paper.
How is this list made?
Every question from the 4 papers (2021-22–2024-25) was mapped to the current AKTU syllabus and grouped with the same question from other years. Questions are ranked by how many papers they appeared in, then by how recently.
Study this subject
Note: this is based on past AKTU papers, not a guarantee. Questions are mapped to the current syllabus; topics that are no longer in the syllabus are left out.