来源：/ 发布时间：2019-12-07 浏览：次
How does the motor start? I'm sure some friends will say that electricity is used. What starting means is the principle of motor starting. Next, we'll introduce the starting methods of several motors in detail.
There are many common types of DC motor: permanent magnet type, series pole type, self excitation type, other excitation type and compound excitation type. The basic structure of a motor is an electrical system composed of a stator coil that generates a magnetic field and an armature coil and a commutator on the rotor that generates power.
After the stator coil is energized, it is also called excitation （except for permanent magnet motor）， which will generate N and S pole electromagnetic fields. The armature coil of the rotor obtains current through the commutator, and the energized conductor will generate magnetic field force in the magnetic field. According to the left-hand rule, it will know its force direction, drive the rotator to rotate and apply different polarity to the two effective sides of the armature coil through the magnetic field through the commutator The direct current of makes the motor run continuously.
AC motor: it can be divided into two categories: asynchronous motor （single-phase motor, three-phase squirrel cage motor and three-phase wound motor） and synchronous motor.
The main structure of asynchronous motor is the stator and rotor winding （squirrel cage is the squirrel cage in the rotor core, winding is the winding coil in the rotor core） starting principle is: the energized stator coil generates alternating electromagnetic field, the closed stator coil generates induced current by cutting the electromagnetic line, and the induced current cuts the magnetic line in the closed conductor to generate electricity The magnetic force drives the motor rotor to rotate, so that the electrical energy can be converted into mechanical energy.
When the synchronous motor is started, the main structure of the synchronous motor is the excitation coil and damping ring on the stator coil and rotor, as well as the conductive collector ring. Synchronous motor has no starting torque, it is asynchronous starting synchronous operation, that is to say, the damping ring （equivalent to squirrel cage of asynchronous motor） on the motor rotor is used to generate starting torque, when the motor is dragged to subsynchronous speed, DC excitation current is applied to the excitation coil to make the magnetic pole of rotor and stator coil attract each other and make the motor run.