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an investigation of dual stator winding induction machines

an investigation of dual stator winding induction machines

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Figure 7.15 Power factor speed characteristics when f = 35 Hz <strong>an</strong>d f = 90 Hz<br />

The XYZ <strong>winding</strong> set is generating when the rotor speed is greater th<strong>an</strong> the<br />

synchronous speed <strong>of</strong> the XYZ <strong>winding</strong> set while the ABC <strong>winding</strong> set produces a<br />

positive torque until the rotor speed reaches the synchronous speed <strong>of</strong> the ABC <strong>winding</strong><br />

set. The output torque <strong>of</strong> the <strong>dual</strong> <strong>stator</strong> <strong>winding</strong> <strong>induction</strong> machine is close to the output<br />

torque <strong>of</strong> the XYZ <strong>winding</strong> set since the electromagnetic torque contributed by the ABC<br />

<strong>winding</strong> set is relatively small.<br />

7.3.6 f = 30 Hz <strong>an</strong>d f = 85 Hz<br />

abc<br />

xyz<br />

The frequency ratio is less th<strong>an</strong> 3 while the frequency <strong>of</strong> the XYZ <strong>winding</strong> set is less<br />

th<strong>an</strong> the rated value in this case. The steady state curves under this condition are given in<br />

Figures 7.16-7.18.<br />

270<br />

abc<br />

xyz

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