Single phase asynchronous motor principle - Introduction

1.Single-phase asynchronous motor is a kind of can convert electrical energy into mechanical energy device, usually the case, the capacity of a single-phase asynchronous motors are relatively small, only single-phase power supply, easy to use, widely used in industry and agriculture and live electrical appliances field, typical applications include: washing machines, electric fans, refrigerators, air conditioners, pumps, blowers, juicer, soybean milk and so on.

2. The single-phase asynchronous motor principle - structures

In the single-phase induction motor, in the form of numerous, but in its generality, the structure of single-phase induction motor by the fixed part, rotating part, the three major components supporting part, etc., refers to the fixed portion of the stator, the rotation section refers to the rotor, and the support portion refers to the end cap and the bearing.

Frame structure with motor cooling, protective type, installation and use vary. Classified according to their material, cast iron, cast aluminum and steel structure and so are several.

Core includes a stator core and the rotor, the role of the three-phase asynchronous motor, is used to form a magnetic circuit of the motor.

Often made of two-phase stator windings: primary and secondary windings. Two winding axis shifted certain electrical angle. Commonly used cage-type rotor winding winding. Commonly used aluminum die-casting.

Cap: corresponding to a different base material, end caps also cast iron, cast aluminum and steel stampings.

Bearing: ball bearing and sleeve bearing.

3. Single-phase asynchronous motor principle

When single-phase asynchronous motor stator winding through the single-phase AC magnetic field is generated case. As shown below, it is a simple, single-phase asynchronous motor schematics, arranged on the stator core will have single-phase stator winding, rotor squirrel cage knot.

After a single pass into the stator windings of the single-phase AC induction motor phase by the figure, when the current in the positive half cycle and a negative half-cycle when the constantly alternating, which produces a magnetic field magnitude and direction will continue change, but will not change the direction of the longitudinal axis of the magnetic field along the axis of the magnetic field at this time is called a pulsating magnetic field.

When the rotor is stationary, the rotor conductor synthesis induced electromotive force and currents are zero, while net torque is also zero, then the rotor does not start torque. So single-phase asynchronous motor if certain measures are not taken, it can not start on its own, this time with a force if the rotor rotates about, the rotor can continue to rotate in the direction to go.