The direct current generator

• In a DC generator current only flows in one direction
• A DC generator has a commutator instead of slip rings
• A current is generated as the coil rotates between the poles
• The coil cuts the magnetic force lines of the magnet

Flow of current in a generator. Image credit electrical4u.com

• A current is thus induced in the coil and collected by the commutator
• As the coil turns there is a change of contact in the vertical position
• One brush remains positive while the other remains negative
• The commutator has a split metal ring which keeps contact with the positive terminal when the coil is on the other side
• And with the negative terminal when it moves to the opposite side as well
• The commutator thus “reverses” the direction of current
• This ensures that the current generated keeps flowing in one direction
• A real world DC generator has more than one coil
• This ensures that the current produced is much smoother and will match that of produced by for example cells
• Other sophisticated methods are also employed to make the generator more usable in the real world

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