What is the homopolar generator?

Homopolar generator is a type of electrical generator that produces direct current (DC) using an electrically conductive disk that rotates inside the static magnetic field. The disc is at right angles to the magnetic field, so its rotation creates a difference between the electrical potential between the center of the disk and its edges. Brush contacts Connect the disk edge to the shaft that turns the disc. The polarity of the electric current depends on the direction of rotation with respect to the magnetic field. It is referred to as "homopolar" or "unipolar" because only one pole of the magnet is used. The stationary magnet and the rotating disc are the most common method, but if the magnet and the disk rotate, energy is still generated. This is possible due to Lorentz's strength, which is the power of electrons caused by an electromagnetic field.

Michael Faraday invented a homopolar generator in 1831, leading to one of his alternative names, Faraday Disc. The first versions of this device were not particularly efficient electricity sources, but showedY principles that now use commuters to produce direct current. The inefficiency of early homopolar generators was mainly due to the countermeasure; The magnet induces the primary flow of current on the part of the disk, which is directly below the magnet, but this current circulates towards the disk areas that are outside the magnetic field. This counterattack warms the disc rather than produces electric current.

Modern homopolar generators will partially solve this problem by arrangement of a number of magnets around the disk perimeter. This allows the magnetic field to remain stable from the center to the edge of the disk. The degree of countermeasures is significantly reduced that increases the efficiency of the generator.

, which is commonly used for demonstration purposes, a small homopolar generator produces only a few volts, while larger generators, such as generators used in scientific research, can produce several hundred volts. Some electrical control systems use more homopolar Gene to produce thousands of voltsRators, but generally do not have many practical industrial uses. The homopolar generator can be made to have a very low resistance, so it can produce a large amount of current, occasionally exceeding 1 million amps.