SU679961A1

SU679961A1 - Method of adjusting variable voltage

Info

Publication number: SU679961A1
Application number: SU752181194A
Authority: SU
Inventors: Валентин Анатольевич Сучков; Валерий Владимирович Ваняев; Кирилл Борисович Набирков
Original assignee: Горьковский политехнический институт им.А.А.Жданова
Priority date: 1975-10-17
Filing date: 1975-10-17
Publication date: 1979-08-15

Description

1one

Изобретение относитс к области электротехники , в частности, преобразовательной техники, и может быть использовано, например, в устройствах дл регулировани и стабилизации переменного напр жени с регулирующим органом дискретного действи .The invention relates to the field of electrical engineering, in particular, to converter technology, and can be used, for example, in devices for regulating and stabilizing alternating voltage with a discrete-action regulator.

Известен способ регулировани переменного напр жени путем ступенчатого изменени уровн выходного напр жени с помощью тиристорных ключей, коммутируемых в моменты нулевых значений тока.There is a method of controlling an alternating voltage by stepwise varying the output voltage level with the help of thyristor switches switched at times of zero current values.

Недостатком известного способа вл етс ограниченное быстродействие регулирующего органа вследствие наличи переходного процесса в моменты переключений ступеней трансформатора, а также возможность выхода из стро тиристорных ключей из-за больщих перегрузок.The disadvantage of this method is the limited speed of the regulator due to the presence of a transient process at the moments of switching the transformer stages, as well as the possibility of going out of thyristor switches due to large overloads.

Целью насто щего изобретени вл етс исключение переходного процесса в трансформаторе , повыщение быстродействи и надежности.The purpose of the present invention is to eliminate the transient process in a transformer, increasing its speed and reliability.

Поставленна цель достигаетс тем, что сначала осуществл ют переключение уровн выходного напр жени на максимальный , потом максимальный уровень измен ют на минимальный, а затем - на требуемый уровень выходного напр жени , причем все переключени соответствующихThe goal is achieved by first switching the output voltage level to the maximum, then the maximum level is changed to the minimum, and then to the desired output voltage level, all switchings of the corresponding

тиристорных ключей производ т в моменты нулевых значений магнитного потока в сердечнике трансформатора.thyristor switches are produced at times of zero magnetic flux values in the transformer core.

При этом следует отметить, что поскольку переход при нулевом магнитном потоке возможен лищь с тиристорных ключей, обеспечивающих меньщее выходное напр жение на тиристорные ключи большего напр жени , то в данный способ вводитс режим наименьщего выходного напр жени , так как переход с этого уровн на любые другие уровни всегда возможен при нулевом магнитном потоке.It should be noted that since the transition at zero magnetic flux is possible only from thyristor keys providing a lower output voltage to thyristor keys of a higher voltage, the mode of the lowest output voltage is introduced into this method, since the transition from this level to any other levels are always possible with zero magnetic flux.

Этим обсто тельством и обуславливаетс наличие в предложенном способе второй и промежуточных операций по переключению тиристорных ключей.This circumstance causes the presence in the proposed method of the second and intermediate operations for switching thyristor switches.

Перва же операци вводитс дл обеспечени надежного запирани тиристорныхThe first operation is introduced to ensure reliable thyristor locking.

ключей в процессе их искусственной коммутации .keys in the process of their artificial switching.

При этом очевидно, что переключение на наименьщий уровень выходного напр жени при нулевом магнитном потоке можноIt is obvious that switching to the lowest level of the output voltage at zero magnetic flux can be

осуществить лищь использу принудительную коммутацию.implement lisch using forced switching.

Электрическа схема устройства, реализующего данный способ регулировани переменного напр жени , приведена на фиг.The electrical circuit of the device implementing this method of adjusting the alternating voltage is shown in FIG.

Claims

1, where indicated:. .. 4,5,679, 2 - secondary and primary windings of booster transformer; 3 - load; 4-13 - thyristor keys; 14-18 - taps of the adjusting transformer; 19, 20 - diodes; 21, 22 - commutation capacitors; 23, 24 - switching thyristors; 25 - current sensor; 26 —Voltage maximum sensor; 27 — control unit; 28 is a control transformer. 10 Timing diagrams explaining the essence of the control method are adapted in FIG. 2, where it is indicated: a is the output voltage curve; b - current curve with active-inductive load; b - voltage curve on the booster transformer; g - curve of the magnetic flux of booster transformer; 20 d, e - control pulses applied to the thyristor keys in a static mode; g - control pulses of the thyristor keys of the maximum level; 25 3 - control pulses of the thyristor switches of the minimum level in the dynamic mode; and - the impulse to control the thyristors of the switching circuit in dynamic zo mode; K, l, m - the moments of the beginning of the switching steps. In this case, the pulses (Fig. 2), generated by the control unit when the current passes through zero, are shown conventionally with a smaller amplitude, and the pulses corresponding to the maxima of the supply voltage eg xni - with a larger amplitude. The essence of the proposed method of regulation is as follows. The output voltage of the device (Fig. 1) is controlled by discretely varying the voltage supplied to the primary winding 2 45 of a booster transformer, for which the transformation ratio of the adjusting transformer 28 is stepwise changed by connecting different pairs of thyristor switches 4-13 to the corresponding - 50 spurs 14-18. The switching of the thyristor switches when operating at the same level (static mode) is carried out when the current passes through zero.55 1 The switching of the thyristor switches when switching from one voltage level to another (the dynamic mode is performed at the maximum of the supply voltage, while switching from the thyristor key pairs to the thyristor keys of the maximum level are carried out by natural switching. Then using switching elements 19-22 and turning on the thyristors 23 and 24 of the artificial switching circuit, switch to the thyristor Key switches of the minimum output voltage level and after that, due to natural switching, transition and thyristor switches of the required output voltage level are performed. All transitions at the required time points are provided by synchronizing the operation of the control unit with 27 signals from the current sensor 25 and the voltage maximum sensor 26. Thus, the proposed method of controlling the alternating voltage in the dynamic mode makes it possible to use a single sequence for any switching pa regulator and the nature of any load that is vidimol1u allow complemented with clear field of application of discrete regulators alternating voltage with a stepped output voltage regulation over a wide range. At the same time, a certain complexity of the logic pays off by increasing the speed of the device. Claims The method of controlling the alternating voltage by changing the output voltage level with the help of thyristor switches, characterized in that, in order to increase the speed and reliability by eliminating the transient process in the transformer, the magnetic flux in the transformer core is controlled and its value changes to zero. the output voltage level to the maximum, then the maximum level is changed to the minimum, and the last to the specified output voltage level.

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