The working principle of the generator

A generator is a mechanical device that converts other forms of energy into electrical energy. It is driven by hydraulic turbines, steam turbines, diesel engines, or other power machinery. It converts the energy from water flow, gas flow, fuel combustion, or nuclear fission into mechanical energy for transmission to generators. The generator is converted to electrical energy. Generators have a wide range of uses in industrial and agricultural production, national defense, technology and daily life.

There are many types of generators, but their working principle is based on the law of electromagnetic induction and the law of electromagnetic force. Therefore, the general principle of its construction is to form magnetic circuits and circuits that conduct electromagnetic induction with each other with appropriate magnetic and conductive materials so as to generate electromagnetic power for the purpose of energy conversion.

Generator structure:

Generators usually consist of components such as stators, rotors, end caps, and bearings.

The stator consists of a stator core, wire wound windings, a frame, and other structural parts that hold these parts.

The rotor consists of rotor iron core (or magnetic pole, magnetic pole) winding, guard ring, center ring, slip ring, fan and shaft.

The stator and rotor of the generator are assembled by bearings and end caps, so that the rotor can rotate in the stator, so as to cut the movement of the magnetic force lines, thereby generating induced electric potentials, which are led out through the connecting terminals and connected in the circuit, and then generate electric current.

The working principle of the generator First, the electromagnetic induction We know that all objects are composed of molecules, the molecules are composed of atoms, the atom is composed of the nucleus and electrons that rotate around it. The nucleus has a positive charge, the electrons have a negative charge, attract each other, and the amount of charge is equal, so the atom does not show electrical properties to the outside world.

Take a straight conductor, the conductor in the magnetic field for "cut" movement of the magnetic induction line, the conductor will produce an induced electromotive force. This is because when the conductor “cuts” the magnetic induction line in the magnetic field, the positive charges and free electrons of the conductor will move in the magnetic field at the same speed, and the magnetic field will generate a force on the motion charge. The direction of the force is determined by the left-hand rule. Therefore, the positive charge moves from the b-end of the conductor to the a-side, and the free electron moves from the a-end of the conductor to the b-side. As a result, electrons are collected at the b-end and become negatively charged. The electrons at the a-end have a positive charge, which causes a certain potential difference between the two ends of the conductor, that is, an induced electromotive force is generated in the conductor. (This is equivalent to the generator running at a constant speed). When the external circuit is turned on, an induced current is formed in the circuit. (This is equivalent to the generator in running power).

The direction of the induced electromotive force can be determined by the right-hand rule: the right palm is to be leveled, the thumb is perpendicular to the four fingers, and the palm faces the magnetic induction line. The thumb points in the direction of the conductor's motion, and the direction of the four fingers is the induced electromotive force. direction. The magnitude of the induced electromotive force in the straight conductor is proportional to the magnetic induction B, the conductor motion velocity v, and the conductor length L. When the conductor moves in the direction parallel to the magnetic field, no induced electromotive force is generated in the conductor.

Second, the sinusoidal alternating electromotive force produces a simple generator diagram of sinusoidal alternating electromotive force.

We can use the graph to represent the change in the magnitude of the potential at each position of the line graph, so that the waveform of the alternating current can be drawn. This sinusoidal regular change of current (or potential) is called sinusoidal alternating current.

Three identical windings A-X, B-Y, and C-Z, which are separated from each other by 120°, are placed on the rotor of the generator. When the rotor is rotating at a constant speed in a sinusoidally distributed magnetic field, three separate symmetrical three-phase potentials eA, EB, EC can be generated.

How diesel generators work Diesel engines drive generators to convert diesel energy into electricity.

In the cylinder of the diesel engine, the clean air filtered by the air filter is fully mixed with the high-pressure atomized diesel fuel injected by the injector. Under the piston's upward compression, the volume is reduced and the temperature rapidly rises to reach the ignition point of the diesel fuel. Diesel is ignited, the mixture gas burns violently, and the volume expands rapidly, pushing the piston down, called 'work'. Each cylinder in turn performs work in a certain order. The thrust acting on the piston becomes a force that drives the rotation of the crankshaft through the connecting rod, thereby driving the rotation of the crankshaft.

By installing the brushless synchronous alternator coaxially with the crankshaft of the diesel engine, the rotation of the diesel engine can be used to drive the rotor of the generator. Using the principle of 'electromagnetic induction', the generator will output the induced electromotive force, and the closed load circuit can generate current. .