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AL TERN A TINC ('('It If EN TS 



ary boosts the line voltage. Figure 255 shows a General Elec- 

 tric induction regulator of this type, disassembled. In this type, 

 the rotor is the primary and the stator the secondary. The 



short-circuited winding at 

 right angles to the pri- 

 mary winding is plainly 

 shown on the rotor. 



The three-phase induc- 

 tion regulator closely re- 

 sembles the three-phase, 

 wound-rotor induction 

 motor. The three stator 

 windings or primaries are 

 connected across the line 

 in either Y or delta. The 

 three secondaries, which 

 correspond to the three 

 phases of a rotor wind- 

 ing, are insulated from 

 one another and each is 

 connected in series with 

 one of the three-phase 

 lines. As the stator pro- 

 duces a uniform rotating 

 field, the induced electro- 

 motive forces in the sec- 

 ondaries are constant and 

 are independent of the 

 position of the rotor. 

 Their boosting and buck- 

 ing effect, however, de- 

 pends upon the phase 

 relations existing between 

 each induced secondary 

 electromotive force and its 

 respective line voltage. 

 The three-phase regulator requires no short-circuited tertiary 

 winding. 



FIG. 256. General Electric feeder voltage 

 regulator assembled, with panel board. 



