A simple switching power supply for 220/15 volts 1 amp. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Power Supplies
Comments on the article
This source can be used to power any load with a power of up to 15 ... 20 W and has smaller dimensions than a similar one, but with a step-down transformer operating at a frequency of 50 Hz.
The power supply is made according to the scheme of a single-cycle pulsed high-frequency converter, fig. 5.1. An oscillator is assembled on the transistor, operating at a frequency of 20 ... 40 kHz (depending on the setting). The frequency is adjusted by the capacitance C5. Elements VD5, VD6 and C6 form an oscillator start circuit.
In the secondary circuit, after the bridge rectifier, there is a conventional linear stabilizer on a microcircuit, which allows you to have a fixed voltage at the output, regardless of changes at the mains input (187 ... 242 V).
The circuit uses capacitors: C1, C2 type K73-16 for 630 V; C3 - K50-29 for 440 V; C4 - K73-17V for 400 V; C5 - K10-17; C6 - K53-4A for 16 V; C7 and C8 type K53-18 for 20 V. Resistors can be any. Zener diode VD6 can be replaced by KS147A.
The pulse transformer T1 is made on a M2500NMS-2 or M2000NM9 ferrite core, size Sh5x5 (the cross section of the magnetic circuit at the location of the coil is 5x5 mm with a gap in the center). The winding is made with PEL-2 wire. Winding 1-2 contains 600 turns of wire with a diameter of 0,1 mm; 3-4 - 44 turns with a diameter of 0,25 mm; 5-6 - 10 turns with the same wire as the primary winding.
(click to enlarge)
Rice. 5.1. Wiring diagram of a 15 W switching power supply
If necessary, there can be several secondary windings (only one is shown in the diagram), and for the operation of the autogenerator, it is necessary to observe the polarity of the connection of the winding phase 5-6 in accordance with the diagram.
Setting up the converter is to obtain stable excitation of the oscillator when the input voltage changes from 187 to 242 V. Elements that require selection are marked with an asterisk "*". Resistor R2 can have a value of 150 ... 300 kOhm, and capacitor C5 - 6800 ... 15000 pF. To reduce the dimensions of the converter in the case of less power removed in the secondary circuit, the values of the electrolytic filter capacitors (C3, C7 and C8) can be reduced. Their value is related to the load power by the ratio:
P - power in the load circuit, W;
Um is the amplitude value of the rectified voltage (for a mains voltage of 242 V acting at the input, the amplitude is 342 V);
Fc - network frequency, for calculating C3 it is taken as 50 Hz;
DU - the maximum range of the rectified voltage ripple allowed for the type of capacitor used (taken from the reference book: for K50-29 it is 10 ... 14%, [L16], i.e. 34 V).
The design of the device case should provide for the installation of a transistor and a stabilizer D1 on radiators, as well as shielding the entire circuit to reduce the level of radiated interference.
Publication: cxem.net
See other articles Section Power Supplies.
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 Solar energy from under the asphalt
16.09.2008
Everyone knows how much asphalt heats up in the summer under the rays of the sun. In Holland, they decided to use this heat.
Beneath the surface of the road is a network of plastic pipes through which water circulates. After heating up under the asphalt, it is pumped into heat exchangers located in the underground aquifer at a depth of about a hundred meters.
This layer is heated to 20 degrees Celsius, and in winter, warm water is passed through a network of pipes under the asphalt, which keeps the road free of ice and snow. In summer, heated asphalt cools and hardens due to pumping water, which reduces its destruction by car wheels.
|
Other interesting news:
▪ Sony Mocopi sensors for avatar motion animation
▪ Cleaner in a freshly painted room
▪ paper that stores electricity
▪ Found the closest black hole to us
▪ Artificial zipper removes odor from manure
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ site section Electrical work. Article selection
▪ Article Playground. Tips for the home master
▪ article How were German neo-Nazis encouraged to give up their beliefs with washing machines? Detailed answer
▪ Glogovin's article. Legends, cultivation, methods of application
▪ article A simple laser burglar alarm system. Encyclopedia of radio electronics and electrical engineering
▪ article Electronic fuse, 6-55 volts 10-600 milliamps. Encyclopedia of radio electronics and electrical engineering
Leave your comment on this article:
All languages of this page
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua
2000-2024
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese