4.4: Rotating Machines
- Page ID
- 55578
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Some network elements are more readily represented by sequence networks than by ordinary phase networks. This is the case, for example, for synchronous machines. synchronous motors and generators produce a positive sequence internal voltage and have terminal impedance. For reasons which are beyond the scope of these notes, the impedance to positive sequence currents is not the same as the impedance to negative or to zero sequence currents. A phase-by-phase representation will not, in many situations, be adequate, but a sequence network representation will. Such a representation is three Thevenin equivalent circuits, as shown in Figure 6
Figure 6: Sequence Networks For A Synchronous Machine