Electrical Machines Objective Questions – Set 20

The fall in speed of the DC generator due to increase in load can be corrected by

The voltmeter connected across a generator reads voltage same at no load and at full load (rated). The generator is of the type

For a specific open-circuit voltage of a DC generator, the short-circuit electric current will be maximum when it is

A generator may loose residual magnetism due to

Due to magnetic saturation, the flux per pole in a DC machine without brush shift

In a Dc generator the magnetic neutral axis coincide with geometrical neutral axis, when

The voltage regulation of a DC generator at full load being zero implies that the generator is

The armature mmf of a DC machine has

Flashing of DC generator means

The armature MMF waveform of a DC machine is

Which of following DC generator will be in a position to build up without any residual magnetism in the field?

In DC generators, the residual magnetism is of the order of

To avoid formation of grooves in the commutator

In large sized DC machines the compensating windings are provided to

The compensating winding in a DC machine

With the increases in field excitation of a DC generator, its generated emf

Short circuiting is caused in the armature winding due to

Which of the following DC generators has rising V-I characteristics?

A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be

A 220 V DC generator is run at full speed without any excitation. The open circuit voltage will be

The slight curvature at the lower end of the OCC of a self excited DC generator is due to

In DC machines, the interpoles are provided

The factors that are responsible for decrease in terminal voltage of a shunt generator are

Flashing the field of DC generator means

In a DC generator, the ripples in the direct emf generated are reduced by employing

In a DC machine the armature mmf is

Open circuited armature coil of a DC machine is

The ___________________ generator has the poorest voltage regulation.

In DC generator on no-load, the air gap flux distribution in space is

If residual magnetism is present in a DC generator, the induced emf at zero speed will be