The three-phase alternator uses the electromagnetic induction principle of cutting magnetic lines of wire to induce electric potential, and converts the mechanical energy of the prime mover into electrical energy for output. Synchronous generator consists of two parts: stator and rotor. The stator is the armature that generates electricity, and the rotor is the magnetic pole. The stator consists of an armature core, evenly distributed three-phase windings, a machine base and an end cover. The rotor is usually a hidden pole type and consists of an excitation winding, an iron core and a shaft, a retaining ring, a center ring, etc.

The stator and rotor of the generator are connected and assembled through the bearings, base and end cover, so that the rotor can rotate in the stator. A certain excitation current is passed through the slip ring, so that the rotor becomes a rotating magnetic field. The stator coil moves to cut the magnetic lines of force, thereby generating an induced electric potential, which is drawn out through the terminals and connected in the circuit to generate a current.

Three-phase generator schematic diagram

Extended information

The three-phase synchronous motor is a type of AC rotating motor, because its speed is always equal to the three-phase synchronous speed And got its name. Three-phase synchronous motors are mainly used as generators and can also be used as electric motors and condensers. In the modern power industry, whether it is thermal power generation, hydropower generation, or nuclear power generation, almost all three-phase synchronous generators are used.

Three-phase synchronous motors are widely used in drives that do not require speed regulation and have high power due to their good characteristics of maintaining a constant speed when the power supply voltage fluctuates or the load torque changes. In mechanical equipment, such as steel rolling mills, turbine compressors, blowers, various pumps and converter units, etc.; or for various ball mills and reciprocating compressors with low driving power but low speed; it can also be used For driving propellers of large ships, etc.

In recent years, as the technology of silicon-controlled frequency conversion devices has become increasingly mature and large-scale, synchronous motors can also operate at variable speed through frequency conversion. Therefore, under a certain control method, the operating characteristics of the three-phase synchronous motor are similar to those of the separately excited DC motor, thus expanding its scope of use.

Baidu Encyclopedia: Three-phase motor