Electrical Machines
Flashing the field of DC generator means

  creating residual magnetism by a DC source.
  neutralising residual magnetism.
 increasing flux density by adding extra turns of winding.
  making the magnetic losses forces parallel.

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Electrical Machines
Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are 4% and 5% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW?

 generator 1 gets over load
 200 MW and 400MW
None of these
 generator 2 gets over load

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Electrical Machines
Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is

 1, 4, 6
 1, 2, 6
 1, 2, 5
 1, 3, 5

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