EE6401-Electrical Machines-1-Important Question April/May 2018
Important Question 13 Marks
- Explain the losses in the Magnetic Materials and how these losses can be minimized.
- Discuss the AC operation of Magnetic Circuits.
- Compare electric and Magnetic circuit.
- Briefly explain about statically & dynamically induced emf.
- Derive the emf equation of a transformer.
- Draw the phasor diagram of transformer on different load conditions
- Predetermine the efficiency of transformer by SC and OC test.
- Explain in detail step by step procedure to draw the equivalent circuit of transformer
- Explain the working of autotransformer, Also derive the expression for the volume of copper of an autotransformer
Unit – III
- Explain the concept of doubly excited magnetic system
- Explain the concept of rotating Magnetic field
- Derive an expression for torque developed in round rotor machine.
- Explain the mmf space wave of a phase of distributed winding.
Unit – IV
- Derive the emf equation of a DC Generator.
- Explain armature Reaction in DC Generators and methods to reduce armature reaction
- Explain the Methods of excitation and characteristics of DC Generators.
Unit – V
- Explain the methods of speed control of DC Shunt Motor
- Need for starter, Explain the working of 3 point starter
- Derive the torque equation of a DC Motor
- Explain Swinburne’s test to predetermine the efficiency of a DC Machine.
- Explain Hopkinson’s test for determining the efficiency of two similar DC shunt Machine
YOU CAN ALSO CHECK THE FOLLOWING HERE