Permanent magnet synchronous motor and screw compressor with same

The utility model discloses a permanent magnet synchronous motor and a screw compressor with the same, which belongs to the technical field of motor heat dissipation. The permanent magnet synchronous motor comprises a motor casing, a motor rear cover, a motor stator, a motor rotor and a motor shaft. The motor rear cover is arranged at the end part of one end of the length direction of the motor casing. The motor stator is arranged in a cavity of the motor casing and is fixed with the inner wall of the motor casing. The motor rotor sleeves the motor shaft. The motor rotor is arranged in a cavity of the motor stator, and a gap is arranged between the motor rotor and the cavity of the motor stator. The permanent magnet synchronous motor is characterized in that a centrifugal fan without a volute is arranged on one side, which is away from the motor rear cover, of the motor rotor; and the centrifugal fan without the volute is arranged the end part of the other end of the length direction of the motor casing, and can coaxially rotate along with the motor rotor. The utility model further discloses the screw compressor driven by the permanent magnet synchronous motor. The permanent magnet synchronous motor and the screw compressor have the advantages that the structure is compact; the cooling effect of the motor is great; the airflow noise and the fan power consumption of the motor can be reduced; and the compressor has the advantages of smooth work and long service life.