Electrical Machine 1

1. Magnetic circuits and its types 33 Minutes _Free

2.B-H relationship and Hystereisis with DC excitation 26 Minutes _Free

3.Hysteresis with AC excitation - Hysteresis loss and Eddy current loss 17 Minutes

4.Faraday's Law of electromagnetic induction , statically and Dynamically induced EMF 11 Minutes

5.Force on current carrying conductor - Expression for self Inductance 10 Minutes

6.Numerical 1 (2076 Baisakh) 18 Minutes

7.Numerical 2 (flux calculation in the core having multiple windings 15 Minutes

8.Numerical 3 (Parallel magnetic circuit) 20 Minutes

9.Numerical 4 (2069 - ring related) 8 Minutes

10.Numerical 5 (2073 Magh - ring related) 12 Minutes

11.Numerical 6 (2069 Bhadra- self inductance) 6 Minutes

1.Construction, Operating Principle and EMF equation of single phase transformer 21 Minutes

2.Mutual Inductance and Coupled circuit model 7 Minutes

3.No load and Load operation of transformer 16 Minutes

4.Equivalent circuit diagram of transformer (Detail) 32 Minutes

5.Capacity of Transformer - Exciting current harmonics - Transformer inrush current 14 Minutes

6.Transformer testing (Polarity test) 7 Minutes

7. Transformer testing ( No Load or Open Circuit test ) 23 Minutes

8. Transformer testing (Short circuit test) 23 Minutes

9. Voltage Regulation 27 Minutes

10. Losses , Efficiency and condition for maximum efficiency in a transformer 20 Minutes

11.Instrument transformer (current transformer & potential transformer) 15 Minutes

12. Auto transformer (Construction , working principle & Cu saving) 17 Minutes

13. Three phase transformer (Introduction) 15 Minutes

14. Three phase transformer connections (Detail) 36 Minutes

15.Three phase to two phase conversion (Scott connection) - Three winding transformer 16 Minutes

16.Parallel operation of single phase and three phase transformer 35 Minutes

17. Numerical 1 (2076 Baisakh - step up transformer testing 30 Minutes

18.Numerical 2 (2072 magh - step down transformer testing) 27 Minutes

19. Numerical 3 (2073 Bhadra - efficiency related) 12 Minutes

20.Numerical 4 (2073 Magh - efficiency related) 7 Minutes

21. Numerical 5 (2071 Magh - efficiency related) 13 Minutes

22. Numerical 6 (2070 magh) 9 Minutes

23. Numerical 7 (2069 bhadra - efficiency related) 20 Minutes

24. Numerical 8 (2072 Ashwin - three phase) 21 Minutes

25. Numerical 9 (2070 Magh - three phase) 18 Minutes

26. Numerical 10 (2069 Poush - three phase) 15 Minutes

1. Constructional details of DC machine and Armature Windings 14 Minutes

2. Operating principle and EMF equation of DC generator 35 Minutes

3. Method of Excitation and Types of DC generator 21 Minutes

4. Characteristics of series, shunt and compound generator 21 Minutes

5. Voltage build up process in DC generator 19 Minutes

6. Armature Rxn in DC generator and methods to reduce Armature Rxn 13 Minutes

7. Losses , efficiency and voltage regulation in DC generator 3 Minutes

8. Numerical 1 (2076 Baisakh - short shunt and long shunt compound dc generator) 54 Minutes

9. Numerical 2 (2075 Bhadra - dc shunt generator) 20 Minutes

1. Operating principle and Torque equation of DC motor 48 Minutes

2. Back EMF and its role in DC motor 15 Minutes

3. Types of DC motor and Performance characteristics of DC motor 38 Minutes

4. starting of DC motors ( 3 point and 4 point starters) 24 Minutes

5. Speed control of DC shunt motor 28 Minutes

6. Speed control of DC series motor 23 Minutes

7. Numerical 1 (2076 Baisakh - dc shunt motor) 23 Minutes

8. Numerical 2 (2075 Bhadra - dc shunt motor) 17 Minutes

9. Numerical 3 (2073 Magh - dc shunt motor) 14 Minutes

10. Numerical 4 (2075 Baisakh - dc series motor) 11 Minutes

11. Numerical 5 (2066 Magh - dc series motor) 13 Minutes

1. Construction and Operating principle of three phase induction motor 34 Minutes

2. Torque equation of three phase induction motor at standstill and running condition 21 Minutes

3. Torque slip characteristics , condition for max. torque & effect of rotor resistance on torque slip characteristics 28 Minutes

4. Testing of induction motor( no load test and blocked rotor test) 25 Minutes

5. Losses , power stages and efficiency of three phase induction motor 16 Minutes

6. Starting methods of three phase induction motor 24 Minutes

7. Speed control methods for three phase induction motor and Double cage Induction motor 11 Minutes

8. Working principle , Voltage build up in an induction generator 28 Minutes

9.Power stage diagram of induction generator 5 Minutes

10. Isolated and grid connected mode of operation of three phase induction generator 23 Minutes

11. Numerical 1 (2074 Bhadra - efficiency related) 14 Minutes

12. Numerical 2 (2073 Bhadra) 21 Minutes

13. Numerical 3 (2076 Baisakh - Torque related) 17 Minutes

14. Numerical 4 (2075 Bhadra - Torque related) 14 Minutes

15. Numerical 5 (2072 Magh- Torque related) 15 Minutes

16. Numerical 6 (2072 Ashwin - Torque related) 12 Minutes

17. Numerical 7 (Testing of induction motor related) 20 Minutes