Patent ID: 8928199
Filing Date: 2015-01-06
Classification: H02K

Abstract:
1. A wound rotor brushless doubly-fed motor for connecting to a power grid power supply and a variable-frequency power supply, the wound rotor brushless doubly-fed motor comprising: an air gap having a circumference; a stator comprising a first set of three-phase windings and a second set of three-phase windings, each winding having pole pairs, wherein there are p a rotor comprising a plurality of slots evenly distributed along the circumference, a number of the plurality of slots being Z′; and one set of multi-phase windings having a plurality of phases, a number of the plurality of phases being m, and having a plurality of winding coils in each phase, each of the plurality of winding coils having an equal span; wherein: Z′ equals to n(p the first set of the three-phase windings is adapted to be connected to the power grid power supply and to receive current from the power grid power supply; the second set of the three-phase windings is adapted to be connected to the variable-frequency power supply and to receive current from the variable-frequency power supply; the rotor is adapted to induce a first rotating MMF and a second rotating MMF in response to the current from the power grid power supply and the current from the variable-frequency power supply, respectively, and rotating direction of the first rotating MMF and rotating direction of the second rotating MMF are opposite to each other; when in use, the rotational speed of the wound rotor brushless doubly-fed motor is variable in response to the variation of the frequency of the variable-frequency power supply; the plurality of winding coils in each phase of the one set of multi-phase windings is disposed in the plurality of slots, and a number of the plurality of winding coils in each of the plurality of slots is zero or one; when p when p