The motor on permanent magnets and its application

A permanent magnet motor is an attempt to reduce the weight and overall dimensions of an electric machine, simplify its design, improve reliability and ease of operation. Such an engine allows and significantly increase the efficiency (efficiency). He received the greatest distribution as a synchronous machine. In this device, permanent magnets are designed and used to create a rotating magnetic field.

At the present time, a combined version is used: permanent magnets together with electromagnets, on the coil of which a constant electric current flows. Such combined excitation provides a lot of positive moments: obtaining the required adjusting characteristics of voltage and speed with decreasing excitation power, reducing the volume of the magnetic system (and, as a consequence, the cost of such a device as a combined motor on permanent magnets) in comparison with the classical system of electromagnetic excitation of a synchronous cars.

To date, the use of permanent magnets is possible in devices with a power of only a few kilovolts-amperes. However, permanent magnets are now being developed with improved characteristics, and the power of the machines is gradually increasing.

The synchronous machine as a permanent magnet motor is used as a direct motor or generator in drives of different capacities. Such devices have found application and distribution in mines, metallurgical plants, thermal stations. Since the synchronous motor works with very different reactive power, it is used in refrigerators, pumps and other mechanisms with a constant speed of operation. The permanent magnet motor is used in low power devices and devices where strict and precise speed constancy is required. These are automatic self-recording instruments, electrical watches, software control devices and so on. At the stations and substations special synchronous generators are installed, producing only reactive power in the idle mode . This power is used for asynchronous motors, and synchronous machines of this type are called "compensators".

The principle of operation of such a machine as a motor on permanent magnets, and in particular a synchronous motor, is based on the interaction of the magnetic field of the rotor (moving part) and the stator (fixed part).

Thanks to the interesting and not yet fully explored properties of magnets, inventions based on them have often appeared and are appearing. For example, one of the most common ideas is the creation of such a device as a non-fuel perpetual motion machine on permanent magnets. From the standpoint of modern science and physics, a perpetual motion machine is impossible (it should have a coefficient of efficiency greater than one, and this is considered unreal), but inventors in the field of alternative energy do not lose hope of creating and developing such an invention.