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connections, called the short shunt and the long shunt,
respectively.
Each of these configurations may be connected so that the
series part of the field adds to the shunt part (cumulative
compounding) or so that it subtracts (differential compounding).

3 Make the following phrases complete.
1. This type of construction is rather common, and poles
constructed in this fashion are called … .
2. The DC machine can produce a nearly constant … .
3. If a machine is in the separately excited configuration, an
additional … .
4. A series resistor can be added to the field circuit to provide
the means for … .
5. The third type of DC machine is the compound-connected
machine, which consists of … .

4 Make a written translation of the following:
To keep this torque angle constant as the rotor spins on its shaft,
a mechanical switch, called a commutator, is configured so the
current distribution in the rotor winding remains constant, and
therefore the rotor poles are consistently at 90◦ with respect to the
fixed stator poles.
In a DC machine, the magnetizing current is DC, so that there is
no spatial alternation of the stator poles due to time-varying
currents.
To understand the operation of the commutator, consider the
simplified diagram of Figure 3.4. In the figure, the brushes are
fixed, and the rotor revolves at an angular velocity ωm; - the
instantaneous position of the rotor is given by the expression: θ =
ωmt − γ.
The commutator is fixed to the rotor and is made up in this
example of six segments that are made of electrically conducting
material but are insulated from one another. Further, the rotor
windings are configured so that they form six coils, connected to
the commutator segments as shown in Figure 3.4.

5 Using Figure 3.5 speak about the configuration of DC
machines.

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