变压器是静止的电气设备，它的主磁场是脉动磁场，•一、二次 绕组 中的电动势和电流具有相同的频率。而异步电动机则是旋转的电气设备，它的主磁场是旋转磁场，转子旋转时，定子、转子绕组中的电动势和电流iV有不同的频率。
Transformer is a static electrical equipment, its main magnetic field is pulsating magnetic field, and the electromotive force and current in primary and secondary windings have the same frequency. The asynchronous motor is a rotating electrical equipment. Its main magnetic field is the rotating magnetic field. When the rotor rotates, the electromotive force and current iV in the stator and rotor windings have different frequencies.
变压器中只有能试的传递，通过主磁场把•一次侧的电能传送到二次侧。异步电动机中除了能世的传递之外，还有能M的转换.即定子绕组中的电能通过主磁场传送到转子绕组以后，有相当大的一部分要转换成机械能，从转子轴上输出给机械负叙。
In transformer, only the test-able transmission can transmit the energy of the primary side to the secondary side through the main magnetic field. In asynchronous motors, besides the energy transfer, there is also the energy M conversion. That is, after the electric energy in the stator winding is transmitted to the rotor winding through the main magnetic field, a considerable part of the energy is converted into mechanical energy, which is output from the rotor shaft to the mechanical negative narrative.