What type of winding would be used for the following:

1.2.1     A high-voltage low-current.

1.2.2     A high-current low-voltage DC machine.     

(1.2)

Step 1:

Winding is a twisting movement or course of wire. 

Types of winding are

                Coil winding machine

                Film winding machine

                Rope winding machine

                wave winding

                Paper winding machine

                Foil winding machine

(1.2.1)

For high-voltage low-current applications wave winding is used.

Wave winding is one type of armature winding. In this winding the end of one coil is connected to the starting of another coil of the same polarity as that of the first coil.

In this winding only two brushes are required but more parallel brushes can be added to make it equal to the number of poles. If one or more brushes set poor contacts with the commutator, satisfactory operation is still possible.

For a given number of poles and armature conductors it gives more emf than that of lap winding. Hence wave winding is used in high voltage and low  current  machines. This winding is suitable for small generators circuit with voltage rating 500-600V.

(1.2.2)

For high-current low-voltage applications foil winding is preferred.