| Start of section
Production, amateur Radio amateurs Aircraft model, rocket-model Useful, entertaining |
Stealth Master
Electronics Physics Technologies Inventions |
Secrets of the cosmos
Secrets of the Earth Secrets of the Ocean Tricks Map of section |
  |
| Use of the site materials is allowed subject to the link (for websites - hyperlinks) | |||
Navigation: => |
Home / Patent catalog / Catalog section / Back / |
|
INVENTION
Patent of the Russian Federation RU2274942
CONVERSION VOLTAGE CONVERTER IN THREE-PHASE VARIABLE
The name of the inventor: Grigorash Oleg Vladimirovich (RU); Rudenko Vadim Grigorievich (RU); Raklo Alexander Victorovich (RU); Novokreschenov Boris Olegovich (RU); Kleshenov Vitaly Alexandrovich
The name of the patent holder: Kuban State Agrarian University
Address for correspondence: 350044, Krasnodar, ul. Kalinin, 13, KubSAU, PIO
Date of the beginning of the patent: 2004.09.15
The invention relates to electrical engineering and is intended for use in autonomous power supply systems for converting the DC voltage into a symmetrical three-phase AC voltage system. The technical result is to improve the reliability of the converter. The converter comprises an inverter (1) consisting of a first and a second transistor (2) and (3), respectively, an inverter capacitor (4), a control unit (5) and a transformer with a rotating magnetic field 6 comprising first and second primary windings 7) and (8), respectively, phase-shifting capacitor 9 and secondary windings (10) - (12), terminals for connecting a DC power supply U d and terminals A, B and C for connecting a three-phase load.
DESCRIPTION OF THE INVENTION
The invention relates to electrical engineering and is intended for use in autonomous power supply systems for converting the DC voltage into a symmetrical three-phase AC voltage system.
The known converter contains three bridge single-phase transistor inverters and a three-phase transformer (Moin BC Stabilized transistor converters .-- M .: Energoatomizdat, 1986, p.314, Fig. 9.1, c). The disadvantages of this converter are low reliability of operation and a high level of electromagnetic interference due to a large number of power semiconductor devices - transistors and the complexity of the control unit providing voltage conversion and its stabilization.
The closest in terms of the technical solution is a converter containing an input capacitor, a single-phase bridge inverter whose power circuit contains four transistors and four diodes, and a transformer with a rotating magnetic field (RF patent No. 2210167, 2003). The disadvantage of the converter is low reliability of operation.
The technical solution of the task is to improve the reliability of the converter.
The task is achieved by the fact that the inverter comprises first and second transistors and an inverter capacitor, wherein the collector of the first transistor is connected to the emitter of the second transistor and to the first terminal of the inverter capacitor, the second terminal of which is connected to the end of the first primary winding of the transformer with the rotating magnetic field, and the emitter of the first Of the transistor is connected to the first terminal of the DC power supply, the collector of the second transistor is connected to the second terminal of the DC power supply and to the first terminal of the phase shift capacitor whose second terminal is connected to the start of the second primary winding of the transformer with the rotating magnetic field, the emitter and the base of the first and second transistors Connected to the control unit, the beginning of the first primary winding of the transformer with the rotating magnetic field is connected to the second terminal of the DC power supply, and its end to the end of the second primary winding of the transformer with a rotating magnetic field that is displaced in space relative to the first by an angle of 90 °, The windings of the transformer with a rotating magnetic field are shifted relative to each other by an angle of 120 °, their beginnings are connected in the "star" scheme, and the ends are terminals for connection of a three-phase load.
The novelty of the claimed technical solution is due to the fact that instead of a single-phase bridge inverter an inverter made on two transistors is used.
According to the data of the scientific, technical and patent literature, the authors do not know the claimed set of characteristics aimed at achieving the task, and this decision does not follow clearly from the prior art, which allows to conclude that the solution meets the level of the invention.
The essence of the invention is explained in the drawing, which shows the circuit diagram of the DC-to-three-phase converter.
 |
The converter comprises an inverter 1 consisting of a first and a second transistor 2 and 3 connected in turn, a capacitor of the inverter 4, a control unit 5 and a transformer with a rotating magnetic field 6 comprising first and second primary windings 7 and 8, respectively, a phase-shift capacitor 9 and secondary windings 10-12. The drawing shows the terminals for connecting a DC power supply U d and terminals A, B and C for connecting a three-phase load. |
TRANSDUCER WORKS AS FOLLOWING
The voltage of the DC power supply U d goes to the input of the inverter 1. Suppose, in the initial state, the capacitor of the inverter 4 is discharged. To generate a positive half-wave voltage in the primary windings 7 and 8 of a transformer with a rotating magnetic field 6, the control unit 5 supplies control pulses to the transistor 2, it opens, and the capacitor of the inverter 4 begins to be charged in such a way that its terminals will have the potentials indicated by the signs in the drawing . The charge current of the capacitor of the inverter 4 will flow through the primary windings 7 and 8 of the transformer with the rotating magnetic field 6 and the phase-shift capacitor 9. To form the negative half-wave of the voltage in the primary windings of the transformer, the control unit 5 closes the transistor 2 and opens the transistor 3. In this case, the capacitor of the inverter 4 Will be a power source for the load, and its discharge current will flow through the primary windings of the transformer 6 and the phase-shift capacitor 9 in the reverse direction.
Thus, alternating current flows through the primary windings 7 and 8 of the transformer 6, which results in the appearance of an alternating magnetic flux in the toroidal magnetic circuit of the transformer. Since the first 7 and the second 8 primary windings of the transformer are displaced in space with respect to each other by an angle of 90 ° and connected through a phase-shifting capacitor 9, a rotating magnetic field is generated in the magnetic circuit of the transformer, causing the EMF in the secondary windings. The secondary windings 10-12 of the transformer are shifted relative to each other by an angle of 120 °, so a symmetrical three-phase system of alternating current voltages is formed at the terminals A, B and C of the converter.
The use of an inverter made on two transistors and an inverter capacitor distinguishes the proposed DC-to-three-phase converter from the known one, since the number of power semiconductor devices in the inverter circuit decreases, the control unit circuit simplifies, which increases the reliability of the converter operation.
CLAIM
A three-phase AC converter comprising a single-phase inverter and a rotating magnetic field transformer, characterized in that the single-phase inverter comprises first and second transistors and an inverter capacitor, wherein the collector of the first transistor is connected to the emitter of the second transistor and to the first terminal of the inverter capacitor, Which is connected to the end of the first primary winding of the transformer with a rotating magnetic field, and the emitter of the first transistor is connected to the first terminal of the DC power supply, the collector of the second transistor is connected to the second terminal of the DC power supply and to the first terminal of the phase shift capacitor whose second terminal is connected to the start Of the second primary winding of the transformer with the rotating magnetic field, the emitter and the base of the first and second transistors are connected to the control unit, the beginning of the first primary winding of the transformer with the rotating magnetic field is connected to the second terminal of the DC power supply, and its end to the end of the second primary winding of the transformer with rotating A magnetic field that is displaced in space relative to the first by an angle of 90 °, three secondary windings of the transformer with a rotating magnetic field are shifted relative to each other by an angle of 120 ° and are connected in a star arrangement, the ends of said secondary windings being terminals for connecting a three-phase load.
print version
Publication date 17.02.2007gg
Comments
Commenting on, remember that the content and tone of your message can hurt the feelings of real people, show respect and tolerance to your interlocutors even if you do not share their opinion, your behavior in the conditions of freedom of expression and anonymity provided by the Internet, changes Not only virtual, but also the real world. All comments are hidden from the index, spam is controlled.