Hardware Reference
In-Depth Information
Figure 4.11: The reluctances in the loop circuit
Figure 4.12: The MMF waveform of the distributed conductors
4.2.2 Rotating Magnetic Field, Pole-pair, Speed and Fre-
quency
For the
fi
eld distribution of motor shown in Figure 4.9, there is only 1 pole-pair
of magnetic
fi
eld produced by the winding is. The winding can be designed
such that the number of pole-pairs produced is 2 as shown in Figure 4.13, or
more. When the harmonic
fi
elds are considered, the relationship between the
pole-pair of the airgap
fi
eld and winding structure becomes complicated which
will be discussed later in section 4.3.
It is clear that a rotating magnetic
fi
eld can be generated in the airgap
by rotating the magnets using mechanical force. However, for the design and
analysis of electric machines, we are more concerned about the realization of
rotating magnetic
fi
eld using electrical means.
