SU1285448A1 - Multistep variable a.c.voltage converter - Google Patents

Abstract

The invention relates to the field of converter technology and can be used to regulate and stabilize an alternating voltage. The purpose of the invention is to simplify and increase efficiency. The voltage is controlled by varying the transformation ratio of the transformer I by changing the order of switching on the thyristors 7-12, 16-27. To obtain the minimum output voltage, the thyristors 11 12, 16, 19, 25, 26 are included. For the first nine control steps, the thyristors 11, 12 are permanently turned on. For the next nine control steps, the thyristors 9, 10 are constantly turned on. The nine stages of regulation corresponding to the maximum voltage continuously switch on the thyristors 8, 7. At the time of switching the thyristors, circuit currents may occur, which are limited by a current limiting link 13. The design of the device allows The loop current is limited to one current-limiting link, thereby simplifying and increasing efficiency. 2 h. item f-ly, 1 silt, 1 tab. i (P

Description

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The invention relates to electrical engineering, in particular, to converter technology, and can be used in devices for regulating and stabilizing alternating voltage.

The purpose of the invention is to simplify and increase efficiency.

The drawing shows a diagram of the device for the number of sections of the adjusting winding 2rt-1 3.

The device contains a transformer 1, input terminals 2 and 3, the main winding of the transformer with intermediate terminals 4 and 5, one extreme terminal of which is connected to the first output terminal 6, thyristor groups 7 and 8, 9 and 10, 11 and 12, common points in series thyristors in each group are connected to the second extreme and intermediate terminals of the main winding of the transformer, and the cathodes of thyristors 7, 9 and 11 through the limiting link 13 are combined with the anodes of the thyristors 10 and 12, the second output terminal 14 connected to the extreme cathode and anode outputs waters of the main thyristor groups 7-12 through an additional control unit 15, which contains additional thyristors 16-27, where the thyristors 16-19 constitute the first, the thyristors 20-23 - the second, the thyristors 24-27 - the third additional group of thyristors, three sections windings separated by an average tap into two equal parts, the first section into parts 28 and 29, the second section into parts 30 and 31, the third section into parts 32 and 33. The end of the first section is located at the junction point of the thyristors 24 and 25, and the end of the third section at the junction point of thyristors 26 and 27. its beginning torus section connected to the second output terminal 14. The number of turns in the sections is: for the first portions 28 and 29 is equal 2VI y; i; for the second of parts 30 and 31 is equal to 4Wya; for the third of parts 32 and 33 is 2Wy; i between pins 4 and 5, pins 4 and the second extreme of the main winding of the transformer W 9W a, where Wv.i is the specific number of turns per volt.

Taking into account thyristors 6–11 of the main groups, the total number of thyristors of such a circuit is L / 6 (n + 1) 18.

The device works as follows.

To obtain the minimum output voltage, the thyristors 12, 11, 16, 19, 25, and 26 must be turned on.

Algorithms for switching on the thyristors of the additional control unit for the first nine stages of the output voltage are given in the table, with the thyristors 12 and 11 being continuously included.

Repeating the algorithm for turning on the thyristors, shown in the table, with the inclusion of the next pair of main thyristors 10 and 9, and then thyristors 8 and 7, the proposed scheme allows for 27 steps

output AC voltage at N 1.8.

At the time of switching from one section of the transformer to another, it is possible that emergency circuit currents occur, which are limited by one current-limiting link for the entire device.

Claims (3)

1.Multi stage adjustable AC voltage converter a variable containing a transformer with K (K any integer) intermediate terminals of the main winding, the first extreme terminal of which is connected to the first output terminal K + 1 of the main groups of thyristors, two series-connected thyristors in each, the second extreme and intermediate to one common points the main winding pins, and the extreme cathode pins of the main groups of thyristors are connected to their extreme anode pins through the current-limiting the link that differs i & vi is that, in order to simplify and increase the efficiency, it is equipped with an adjusting winding containing 2n-1 sections with average leads and three additional groups, thyristors, 2 "each (l any integer) of consecutively connected thyristors each, the extreme cathode and anode outputs of all additional thyristor groups are combined with the extreme cathode and anode outputs of the main thyristor groups, respectively, in this case, both extreme and average outputs of each section are connected to common connection points of the corresponding thyristors of each of the additional groups, and one of the extreme conclusions of the nth section is connected to the second output output. 2. The converter according to claim 1, is different, because with n odd, the beginning of all odd and the ends of all even, and with even n - the beginning of all even and the ends of all not The even-numbered sections are located at the connection point of the thyristors of an additional group, having a zero point with a second output terminal, while the p-section is connected according to the main winding of the transformer. 3. The converter according to claim 1, characterized in that the number of turns in the sections with / 1, 2, 3 ... rt is selected according to the law Зг - (- 1) Ц7уд  il at / l, 1, ... (2n + 1) - by law ( Wi . and the number of turns between adjacent terminals, except the first extreme, the main winding of the transformer according to the law W 3 -W ,, where L is the section number; .i is the unit number of turns per volt.