There are three main operation modes of synchronous motor, that is, as generator, motor and compensation machine.
As the generator operation is the most important operation mode of synchronous motor.
As an operation of the motor, it is another important operation mode of the synchronous motor. The power factor of synchronous motor can be adjusted. The application of large synchronous motor can improve the operation efficiency without the need of speed regulation. Small synchronous motor has been widely used in variable frequency speed regulation system.
The synchronous motor can also be connected to the power grid as synchronous compensator. At this time, the motor without any mechanical load, by regulating the excitation current in the rotor to the grid to send the required inductive or capacitive reactive power, in order to achieve the purpose of improving the power factor of the grid or regulating the grid voltage.
Synchronous generators, like other types of rotating machines, consist of two parts: a fixed stator and a rotatable rotor. It can be divided into transition type synchronous motor and rotary hub synchronous motor.
The most commonly used is synchronous generator. The inner circle of the stator core is evenly dispersed with the stator slot, and the slot is embedded with a three-phase symmetrical winding arranged in accordance with the law. The stator of the synchronous motor is also called armature, and the stator core and winding are also called armature core and armature winding.
The rotor core is made up of pairs of poles which must be made of shape. There is an exciting winding around the magnetic pole. When the DC current is applied, the magnetic field will be formed in the air gap of the motor, which is called the exciting magnetic field (also called the main magnetic field and rotor magnetic field).
The prime mover drives the rotor to rotate (the mechanical energy input to the motor). The exciting magnetic field between the poles rotates along with the shaft and cuts the stator windings in turn (equivalent to the winding conductor cutting the exciting magnetic field).