SYNCHRONOUS/ASYNCHRONOUS MOTOR Russian patent published in 1999 - IPC

FIELD: electrical engineering; multiphase double-speed drives. SUBSTANCE: motor stator has multiphase pole-changing winding with numbers of pole pairs P₁:P₂; rotor winding is combination of high-speed three-phase winding with pole pair number P = P₁ and low-speed DC field winding with pole pair number P = P₂. Proposed double-speed motor runs at high speed as squirrel-phase induction motor and at low speed, as synchronous motor showing high stability in case of supply voltage fluctuations. EFFECT: high overload capacity of double-speed motor at low speed. 2 dwg