SIX-TO-FOUR AND FOUR-TO-SIX POLE-CHANGING WINDING Russian patent published in 1999 - IPC

FIELD: dual-speed motors. SUBSTANCE: motor stator has 36 slots accommodating winding of 21 coil groups; coil number in coil groups is alternating as follows: 1,3,2,4,1,1,1,1,3,2,31; 1,1,2,2,2,1,1,1; coil group finishing lead 2 is connected to finishing lead 6; finishing lead 19, to finishing lead 3; starting lead 3, to starting lead 8; starting lead 21, to starting lead 4; finishing lead 5, to finishing lead 10; starting lead 10, to starting lead 15; starting lead 7, to starting lead 11; finishing lead 9, to finishing lead 13; finishing lead 12, to finishing lead 17; starting lead 17, to starting lead 1; finishing lead 16, to finishing lead 20; combined finishing leads 1, 8, 15 of coil groups form terminal lead 22; combined starting leads 5, 21 and finishing lead 16 of coil groups form terminal lead 23; combined starting leads 2, 12 and finishing lead 7 form terminal lead 24; combined leads 9, 19, and finishing lead 14 form terminal lead 25; combined finishing leads 4, 11, 18 form terminal lead 26; combined starting leads 6, 13, 20 form terminal lead 27. When voltage is applied to leads 23, 24, 25, motor runs as four-pole machine and when it is applied to leads 22, 26, 27, it is changed over to six-pole winding. EFFECT: reduced unbalance of internal-voltage vectors in parallel circuits of winding at four pole pairs. 5 dwg