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期中報告
授課教授：秦純 教授
班級：碩研電機一甲
姓名：吳旻鴻
學號：MA020127
Question 4.12
 The three-phase synchronous machine of Problem 4.9 is to be moved to an
 application which requires that its operating frequency be reduced from 60 to
 50Hz. This application requires that , for the operating condition considered in
 Problem 4.8, the rms generated voltage equal 13.0 kV line-to-line. As a result,
 the machine armature must be rewound with a different number of turns.
 Assuming a winding factor of Kw=0.928, calculate the required number of
 series turns per phase.
Answer
線電壓的均方根值
由4.9可知
因此
Question 4.18
 A two-pole, 60 Hz, three-phase, laboratory-size synchronous generator has a




rotor radius of 5.71 cm, a rotor length of 18.0 cm, and an air-gap length of 0.25
mm. The rotor filed winding consists of 264 turns with a winding factor of kr =
0.95. The Y-connected armature winding consists of the 45 turns per phase with
a winding factor kw = 0.93.
a. Calculate the flux per pole and peak fundamental air-gap flux density which
will result in an open-circuit, 60-Hz armature voltage of 120 V rms / phase
(line-to-neutral).
b. Calculate the dc field current required to achieve the operating condition of
part (a).
c. Calculate the peak values of the field-winding to armature-phase-winding
mutual
inductance.
(a)
Answer
φ=BA(wb)
(b)
(c)