Trans-synchronous motor appts. using time staggering technique - generates speeds which are fractions of synchronous speeds using triacs, logic circuit and crossing detector

摘要

In one example of a preferred motor three symmetrically geometrically displaced windings A,B and C with six magnetic pos, connected in Y-fashion. Clearly the device may be used with other types of winding connections and other even numbers of magnetic poles. The windings have their output terminals connected to a power source AC - in this case, a single phase source - with the AC neutral line, so-labelled, at the common connection point P' of the windings A,B and C. Triacs or other switching devices a, b and c respectively connect the inner pole terminals of the respective windings A, B and C with the common point P'. The respective switching triacs a, b and c are triggered from leads III, IV and V of the output of a three-phase ring counter RC, controlled by the output II of a zero-axis-crossing detector D that produces a pulse for each zero-crossing of the waveform I of the input 60-cycle line.