Structure of domestically produced servo motor AC servo motors can be divided into two main parts, namely stator and rotor parts. With the resolver stator stator structure is basically the same, also placed in the stator two-phase winding space at a 90-degree angle to each other. One group for the excitation winding, another set of control winding, a two-phase AC servo motors AC motor. When using AC servo motor, excitation winding ends of applying a constant excitation voltage Uf, controlling both ends of the coil control voltages Uk.