Harmonics in the exciting current of transformers . FIGURE 3. » 5 As said before the exciting current can be broken up into wattless andenergy components , the hysteresis power current i , and the react-ive magnetizing current i are plotted in Figure 4 and show that i is nearly a sinewave and i is greatly distorted . Thus the wattless or magnetizing current componentof the exciting current causes the distortion .. FIGURE 4. 6 SINGLE PHASE . The best method of studying the exciting current is by means of the oscillc-graph . In the investigation of the harmonics causing distorte
Harmonics in the exciting current of transformers . FIGURE 3. » 5 As said before the exciting current can be broken up into wattless andenergy components , the hysteresis power current i , and the react-ive magnetizing current i are plotted in Figure 4 and show that i is nearly a sinewave and i is greatly distorted . Thus the wattless or magnetizing current componentof the exciting current causes the distortion .. FIGURE 4. 6 SINGLE PHASE . The best method of studying the exciting current is by means of the oscillc-graph . In the investigation of the harmonics causing distorted waves it is necess-ary to know the shape of the electromotive force wave impressed u^on the transformercircuits or primaries . Plate I shows the reproduction of the oscillogram taken of the electromot-ive force wave of a three phase alternator used to supply power in the tests . Uponexamination of this wave , it is seen that it is very nearly a sine wave , onlyhigh harmonics existing , the magnitude of which were too small to cause any appre-ciable error when neglected so that the wave may be considered a sine wave . It isexplained in the proceeding paragraphs that the flux wave will be a sine wave andthat the exciting current v/ill have a distorted appearance . Plate 2 shows the exciting current wave for a single transformer with theelectromotive force shown in Plate I impressed . This wave is distorted and peakedand wa
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttheses, bookyear1912
