Pole-changing, three-phase, alternating current, electric motors and generators

Claim 1

FOR A POLE-CHANGING ROTARY ELECTRIC MACHINE HAVING A THREE-PHASE ALTERNATING CURRENT WINDING COMPRISING THREE PHASE-WINDINGS EACH WITH COILS WOUND AND CONNECTED TO PROVIDE A FIRST NUMBER OF POLES OTHER THAN THREE POLEPAIRS OR A MULTIPLE THEREOF AND HAVING SWITCH MEANS FOR RECONNECTING THE COILS OF EACH PHASE-WINDING ACCORDING TO A POLE-AMPLITUDE MODULATION WAVE EXTENDING OVER THE THREE-PHASE WINDING AS A WHOLE, SAID WAVE COMPRISING AN ODD NUMBER OF COMPLETE CYCLES OTHER THAN THREE OR A MULTIPLE THEREOF, WHEREBY A SECOND NUMBER OF POLES IS PROVIDED WHICH NUMBER IS THREE POLE-PAIRS OR A MULTIPLE THEREOF, A MAGNETOMOTIVE FIELD CORRESPONDING TO A THIRD NUMBER OF POLES, WHICH NUMBER IS NOT THREE POLE-PAIRS OR A MULTIPLE THEREOF BEING SUPPRESSED BY THE ARRANGEMENT OF THE COILS OF THE THREE-PHASE WINDING, A METHOD OF SELECTING SAID COILS FOR RECONNECTION TO PROVIDE SAID SECOND NUMBER OF POLES COMPRISING SELECTING A FRAME FOR THE SAID THREE-PHASE WINDING WHICH HAS SUBSTANTIALLY THREE SLOTS PER POLE PER PHASE, OR A MULTIPLE THEREOF, FOR THE SAID SECOND NUMBER OF POLES AND SELECTING SUBSTANTIALLY ONEHALF THE TOTAL NUMBER OF COILS OF EACH PHASE-WINDING FOR REVERSAL IN CIRCUIT UPON SAID RECONNECTION IN A MANNER BOTH TO PROVIDE THE SAID POLE-AMPLITUDE MODULATION WAVE EXTENDING OVER THE THREE-PHASE WINDING AS A WHOLE AND TO PROVIDE THAT EACH PHASE-WINDING IS SUBSTANTIALLY GEOMETRICALLY BALANCED ABOUT THE NEUTRAL LINE FOR THE PHASE, AS SHOWN BY A SLOT-STAR DIAGRAM FOR EACH OF THE THREE PHASE-WINDINGS.