The principle of magnetron generating microwaves is mainly based on the interaction of electrons in magnetic and electric fields, as well as the coupling effect of resonant cavities.

1、 Basic principles

Magnetron is a device that can convert electrical energy into microwave energy, fully known as magnetron oscillator. Its working principle involves the motion of electrons in constant magnetic and electric fields, as well as the interaction between these electrons and the resonant cavity.

2、 The motion of electrons in magnetic and electric fields

Electron emission: The cathode in a magnetron is the main source of electron emission. When the filament is heated, the cathode emits electrons.
Electron acceleration: These electrons are accelerated under the action of anode voltage, forming an electron flow.
Magnetic field effect: At the same time, electrons are also subjected to a constant magnetic field, causing their direction of motion to deflect and rotate around the cathode. This rotational motion increases the time spent by electrons in the interaction space, thereby improving radiation efficiency.

3、 The interaction between electrons and resonant cavities

Excitation resonant cavity: The electron flow in rotational motion excites the coupled resonant cavity, generating a high-frequency alternating electric field.
Energy conversion: The high-frequency alternating electric field interacts with the electron flow, slowing down the electrons and converting their kinetic energy into microwave energy. This is a process of energy conversion, in which the kinetic energy of electrons is converted into the energy of microwave radiation.

4、 Establishment and stability of microwave oscillation

Favorable and unfavorable electrons: During synchronous motion, some electrons (favorable electrons) are in the microwave deceleration field, and they transfer their energy to the microwave field; And another part of the electrons (unfavorable electrons) are in the microwave acceleration field, obtaining energy from the microwave field. When unfavorable electrons return to the cathode, secondary electrons are ejected, which participate in the microwave oscillation process together with the original electrons.
Automatic phase focusing: Through the phenomenon of automatic phase focusing, unfavorable electrons gradually transform into favorable electrons and form a spoke shaped electron cloud in the interaction space. The formation of this electronic cloud helps stabilize microwave oscillations.


 

5、 Output of microwave energy

The microwave oscillation energy generated inside the resonant cavity is extracted through the coupling loop inside the cavity, which becomes the microwave power output. These microwave energies can be used in various occasions that require microwave heating or processing, such as microwave ovens.

The principle of magnetron generating microwaves is the interaction of electrons in a constant magnetic field and electric field, as well as the coupling effect between electrons and a resonant cavity. Electrons interact with the resonant cavity to generate high-frequency alternating electric fields during acceleration and rotation, converting kinetic energy into microwave energy and outputting microwave power through a coupling loop. This process involves complex physical phenomena and energy conversion mechanisms, which are the key to the ability of magnetrons to generate microwaves.