TransactionsPublished under the care of the General Secretary and the Treasurer . al number of slots on pri-mary and secondary, and may be assimied to be practically constantThus the excess (over the initial value) is due entirely to the beltleakage, which does not reach its maximum value at the half-beltpoint (position 2), since at that point the belt-leakage path has arelatively high reluctance. In the case of Fig. 13, curve I is the same as curve IT of Fig. curve II the rotor winding was connected up six-phase, andfor curve III, twelve-phase. The belt leakage is shown clearly byVol. 1
TransactionsPublished under the care of the General Secretary and the Treasurer . al number of slots on pri-mary and secondary, and may be assimied to be practically constantThus the excess (over the initial value) is due entirely to the beltleakage, which does not reach its maximum value at the half-beltpoint (position 2), since at that point the belt-leakage path has arelatively high reluctance. In the case of Fig. 13, curve I is the same as curve IT of Fig. curve II the rotor winding was connected up six-phase, andfor curve III, twelve-phase. The belt leakage is shown clearly byVol. 1 — 46 722 ADAMS: LEAKAGE liEACTAXCE OF IXDUCTIOX MOTORS. the areas between these curves. These areas also show how rapidlythe belt reactance increases with the minimum belt pitch, A,(equation 8). For curve IV both rotor and stator were rewound for eightpoles, and for curve Y IG-pole windings were employed. Hereagain the effect of changing the belt pitch is clearly shown, butwith the difference that the initial values are altered, due to thechanged lencrth of end .2 .4 .G .8 Stator Core #2. Rotor Core #2. Air Gap =.5~ I Three phase 4 pole winding on Stator and Rotor II Stator 3 phase 4 pole; Rotor 6 phase 4 pole III 12 one slot per pole per phase IV Three phase 8 pole winding on Stator and,RotorV V 16 VI Stator 3 phase 16 pole; Rotor made into squirrel cage with bars hayingsame location in slots as former winding. Fig. 13. Another test was made with the rotor connected two-phase, theresult being just what was predicted, an average increase of beltreactance, but a much-reduced variation of total reactance, due tothe shorter belt cycle. The experimental results considered above show clearly that evenin the case of 3-phase, 60 cycle motors, the belt reactance playsan important part in the variation of the total reactance with rotorposition, and that in the case of lower frequencies it becomes stillmore prominent. Therefore if a reaso
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