Miniature permanent magnet synchronous motor

Abstract

The invention discloses a miniature permanent magnet synchronous motor which comprises a stator and a permanent magnet rotor which have equal number of poles. An alternating current source supplies power to the stator through a switch of a control circuit, and an air gap between the stator and the rotor narrows down from one pole to another pole along the rotating direction so that the axis of each pole of the rotor under free state deflects for an acute angle along the rotating direction by taking the axis of the nearest pole of the stator as the reference. A linear magnetic position sensor is installed at a set position on the circumference of the rotor so as to detect the polarity and the position of the rotor; the control circuit determines the axis direction of the permanent magnetic flux of all the poles of the rotor according to the output of the sensor and by taking the set position as the reference. The control circuit detects the polarity of the voltage supplied to the stator by the power source so as to determine the axis direction of the main fluxes generated by all the poles. The switch switches on the power source half-wave when the motor is started and the intersection angle between the axis direction of the main fluxes and the axis direction of the permanent magnetic fluxes is the above acute angle or when the motor runs and the axis direction of the main fluxes is opposite or approximately opposite to the axis direction of the permanent magnetic fluxes. The motor has good starting performance in preset rotating direction and good operational performance and the control structure of the motor is simple and reliable.

Description

technical field [0001] The invention relates to a miniature permanent magnet synchronous motor, in particular to a miniature permanent magnet synchronous motor directly driving a small-power centrifugal water pump. In the international patent classification table, the classification can belong to H02P6 / 20. Background technique [0002] Compared with the asynchronous motor, the traditional miniature permanent magnet synchronous motor directly driving the small-power centrifugal water pump is obviously energy-saving and material-saving, but its uncertain direction of rotation and low torque or uneven operation affect the use effect. The existing technology has been improving Efforts for this deficiency can be found in the Chinese invention patent application publication specification CN1275257A and the Chinese utility model patent specification CN201409107Y. However, the control structures of these designs in the prior art are rather complicated, and the practical effect is st...

AI Technical Summary

Problems solved by technology

[0002] Compared with the asynchronous motor, the traditional miniature permanent magnet synchronous motor directly driving the small-power centrifugal water pump is obviously energy-saving and material-saving, but its uncertain direction of rotation and low torque or uneven operation affect the use effect. The existing technology has been improving Working hard for this deficiency can be found in the Chinese invention patent application publication specification CN1275257A and the Chinese utility model patent specification CN201409107Y

However, the control structure of these designs in the prior art is rather complicated, and the actual use effect is still not good.

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