The invention discloses a pole-changing control
permanent magnet synchronous motor, relating to a pole-changing control
permanent magnet synchronous motor system and belonging to the field of motors. The
synchronous motor is characterized in that permanent magnets of a rotor (secondary) are divided into strong-
magnetism permanent magnets and weak-
magnetism permanent magnets, wherein the weak-
magnetism permanent magnets are not magnetized before the operation of the motor,
magnet limbs and grooves at / in the surface of the air gap side of the rotor (secondary) are alternatively arrayed along the directions of relative motions of the rotor (secondary) and a
stator (primary), the strong-magnetism permanent magnets and the weak-magnetism permanent magnets are alternatively arrayed along the directions of relative motions of the rotor (secondary) and the
stator (primary) according to a certain rule; and the strong-magnetism permanent magnets are embedded into the grooves, and the weak-magnetism permanent magnets are fixed on the surfaces of the
magnet limbs. According to the pole-changing control
permanent magnet synchronous motor, in an application process, the polarity of the
magnetic field of the rotor (secondary) can be controlled according to a direct-axis component of the current of the
stator (primary), the changing of the number of poles of the main
magnetic field of the motor is realized, and furthermore, and the torque (push force) in
low speed of the motor and the efficiency in high speed of the motor are improved, so that the speed adjustable range of the motor is broadened.