In the protection of transformers, harmonic restraint is used to guard against

Initial inrush of magnetizing currents have high component of even and odd harmonics.
2nd - 63%
3rd -26.8%
4th- 5.1%
5th- 4.1%
6th- 3.7
7th-2.4

The corona effect can be minimized by increasing

Corona can be reduced by using large size of conductor, bundle conductor and hollow conductor.

Which motor is used to start heavy loads?

Torque in d.c motor = k* φ * Ia
In series motor φ α Ia
Tα I²
starting torque of dc series motor is high

DC series motors are best suited for traction work because

Torque in d.c motor = k* φ * Ia
In series motor φ α Ia
Tα I²
N α 1/φ
N α 1/T

Fot fast load flow calculations, the best method is

If the percentage reactance of the system upto the point of fault is 20% and the base kVA is 10,000 the short ciruit kVA is

Short circuit kVA = Base kVA/%X