1. overview of single-phase asynchronous motor is composed of rotary resistance single-phase AC power supply, the stator winding single-phase single-phase AC power supply. When access, it generates an alternating pulsed magnetic field in the air gap of the stator and rotor, the magnetic field in the space not only rotating, the magnetic flux and the magnetic induction of the sinusoidal changes with the size time and space. A fixed axis, pulsating magnetic field size changes as sine wave, can be decomposed into two equal speed, the rotating magnetic field in the opposite direction. When the rotor is at rest, the synthesis of the electromagnetic torque two rotating magnetic field is zero, so the single-phase asynchronous motor can not be started.In order to make the single-phase asynchronous motor self starting. It is going to produce a rotating magnetic field at startup. This can be used to realize the self starting phase capacitance of single-phase asynchronous motor. The wiring principle diagram of capacitor phase asynchronous motor stator. There are two winding, AX is winding, BY is the starting winding, winding and BY series capacitor, two axis winding in the space perpendicular to each other. By properly choosing the circuit parameters so that the current iB BY in advance of 90 DEG winding than the current iA AX winding in phase. So, after electrify a the rotating magnetic field produced in the air gap and rotor set will sub, the single-phase asynchronous motor to start. Two current iA B, as shown by the rotating magnetic field generated by the direction is from BY to AX, which is ahead of the winding current (BY) to the winding current delay (AX), as a clockwise direction in the rotation. Under the effect of rotating magnetic field, the rotor will rotate along the clockwise direction. 

2 motor reversal to single-phase asynchronous motor reversal, lies in the rotation direction of the rotating magnetic field changes, but not like a three-phase asynchronous motor that rely on swap two power line to achieve. Through the analysis, caused by single-phase asynchronous motor rotating magnetic field is reverse change iA and iB advanced lagged relationship. If the iB iA 90* in advance to make a single-phase asynchronous motor clockwise rotation for the forward, then to make the single-phase asynchronous motor reversal, as long as the iA ahead of iB90*. Through the capacitor. Split phase asynchronous motor phase current waveform inversion wiring diagram change windings and power connection circuit as shown in the first end winding AX and 2 power line connection terminal X connected to the power line 1. Connection mode change will make the current phase around the group iA in AX changed, namely iA reverse then iA from iB90* to iB90* in advance lag so also causes the rotating magnetic field reverse, single-phase asynchronous motor reversal. Two phase current as shown. The capacitor phase asynchronous motor phase current waveform inversion connection conclusion In summary, if the use of single-phase asynchronous motor starting capacitor split phase method, can be used to change the capacitance of C series, realize the connection and change the working windings and power connection and power supply branch started to change the above method. After experimental verification, the feasible.