Classification of electric motors. Scheme, description

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
Free library / Electrician

Classification of electric motors. Encyclopedia of radio electronics and electrical engineering

Free technical library

Encyclopedia of radio electronics and electrical engineering / Electric motors

Depending on the type of current used in the electric machine, they are divided into motors DC и alternating current, as well as universal (collector). Each type of engine has both advantages and disadvantages.

The device of AC motors is simpler, therefore, it is much easier to work with them. However, it is almost impossible to control the speed of such engines. This limits the scope of their application to devices in which there is no need to adjust the speed, for example, in electric saws and similar mechanisms.

Structurally, in the most general form, AC electric motors consist of two main parts: a fixed part - stator and rotating part - rotor (Fig. 97).

Rice. 97. The device of a three-phase motor series 4A: 1 - shaft; 2 - fixing key; 3 - bearing; 4 - stator; 5 - stator winding; 6 - rotor; 7 - fan; 8 - terminal box; 9 - paw.

Release them single-phase и multiphase, and the power consumption is in the range from 0,2 to 200 kW or more.

The design of DC motors also includes a moving part - anchor and motionless stator. The stator and armature windings in these motors can be connected in series, in parallel and in combination. Their undeniable advantage over AC motors is the ability to control the speed. They are mainly used in industrial installations where there is a precise speed limit.

In household electrical appliances - refrigerators, vacuum cleaners, juicers, etc. - universal collector motors are used, designed to operate both from alternating current with a frequency of 50 Hz (voltage 127 and 220 V) and from direct current (voltage 110 and 220 V) .

Collector motors have low power - up to 600 W; maximum speed - up to 8000 rpm. The rotational speed in them is regulated by changing the value of the voltage supplied to their windings: if the engine is low-power, then the voltage change is carried out by connecting a rheostat; for more powerful motors, a transformer is used.

The advantage of collector motors is primarily their versatility. The disadvantages include the impossibility of working at low loads, that is, idle (the engine overheats in this mode); low efficiency when operating on alternating current; the occurrence of radio interference during engine operation. True, the last drawback can be reduced if the excitation winding is symmetrical, that is, the armature is turned on on both sides.

Author: Korshevr N.G.

See other articles Section Electric motors.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Machine for thinning flowers in gardens 02.05.2024

In modern agriculture, technological progress is developing aimed at increasing the efficiency of plant care processes. The innovative Florix flower thinning machine was presented in Italy, designed to optimize the harvesting stage. This tool is equipped with mobile arms, allowing it to be easily adapted to the needs of the garden. The operator can adjust the speed of the thin wires by controlling them from the tractor cab using a joystick. This approach significantly increases the efficiency of the flower thinning process, providing the possibility of individual adjustment to the specific conditions of the garden, as well as the variety and type of fruit grown in it. After testing the Florix machine for two years on various types of fruit, the results were very encouraging. Farmers such as Filiberto Montanari, who has used a Florix machine for several years, have reported a significant reduction in the time and labor required to thin flowers. ... >>

Advanced Infrared Microscope 02.05.2024

Microscopes play an important role in scientific research, allowing scientists to delve into structures and processes invisible to the eye. However, various microscopy methods have their limitations, and among them was the limitation of resolution when using the infrared range. But the latest achievements of Japanese researchers from the University of Tokyo open up new prospects for studying the microworld. Scientists from the University of Tokyo have unveiled a new microscope that will revolutionize the capabilities of infrared microscopy. This advanced instrument allows you to see the internal structures of living bacteria with amazing clarity on the nanometer scale. Typically, mid-infrared microscopes are limited by low resolution, but the latest development from Japanese researchers overcomes these limitations. According to scientists, the developed microscope allows creating images with a resolution of up to 120 nanometers, which is 30 times higher than the resolution of traditional microscopes. ... >>

Air trap for insects 01.05.2024

Agriculture is one of the key sectors of the economy, and pest control is an integral part of this process. A team of scientists from the Indian Council of Agricultural Research-Central Potato Research Institute (ICAR-CPRI), Shimla, has come up with an innovative solution to this problem - a wind-powered insect air trap. This device addresses the shortcomings of traditional pest control methods by providing real-time insect population data. The trap is powered entirely by wind energy, making it an environmentally friendly solution that requires no power. Its unique design allows monitoring of both harmful and beneficial insects, providing a complete overview of the population in any agricultural area. “By assessing target pests at the right time, we can take necessary measures to control both pests and diseases,” says Kapil ... >>

Random news from the Archive

Google is looking for female programmers 26.06.2014

Google launched the Made with Code initiative to get more American schoolgirls into programming. Its author was Susan Wojcicki, sister of Anna Wojcicki, wife of Google co-founder Sergey Brin. In February 2014, Susan Wojcicki was appointed by Google to be the CEO of YouTube.

"My daughter is of school age. She instinctively knows how to play games, watch videos and chat with friends. I mean, she understands technology. And she loves using it. But she has never shown any interest in using technology to do anything." create. That's why I decided to create said project," shared Susan Wojcicki.

As part of Made with Code, Google plans to spend $50 million on teacher rewards and funding for various US projects dedicated to teaching programming.

Instructors will be able to earn rewards for their work at institutions such as Codecademy and Khan Academy, which teach programming in HTML, CSS, JavaScript, PHP, Python and Ruby.

Participants in the Khan Academy project, for example, receive a $100 reward for each student who completes a programming course, and a $500 bonus for four students. These funds can then be used by educators to purchase learning materials at DonorsChoose.org.

As part of Made with Code, a web portal of the same name was also created. It invites you to get acquainted with the Blocky constructor, which allows you to build applications in a web browser using blocks. On the site you can watch a video about how some girls and women are already using computer programs in work, research and creativity.

Now at Google, only 17% of the technical staff are women. According to the American Association of University Women, less than 1% of high school students are interested in a professional career in programming. At the same time, over the past 30 years, the number of girls in the United States graduating from educational institutions in a specialty related to computer technology has fallen from 40% to 14%.

Other interesting news:

▪ Apple to switch to recycled cobalt, gold, tin and rare earths

▪ Laptops with a preinstalled OS will be released less

▪ Video hit from Gigabyte

▪ Masked erythrocytes

▪ The danger of global warming for aircraft

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Lecture notes, cheat sheets. Selection of articles

▪ article Gradation of batteries by quality. video art

▪ article What does the heart do? Detailed answer

▪ Article Bilberry ordinary. Legends, cultivation, methods of application

▪ article Simulator of sounds for a shooting gallery. Encyclopedia of radio electronics and electrical engineering

▪ article Square on the calendar. Focus Secret

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews