SU888302A1

SU888302A1 - Three-phase thyristorized voltage inverter

Info

Publication number: SU888302A1
Application number: SU772444525A
Authority: SU
Inventors: Иван Федорович Калинин; Владимир Исакович Степанов; Деметра Игоревна Степанова
Priority date: 1977-01-18
Filing date: 1977-01-18
Publication date: 1981-12-07

Description

(5) ТРЕХФАЗНЫЙ ТИРИСТОРНЫЙ ИНВЕРТОР НАПРЯЖЕНИЯ(5) THREE PHASE THYRISTOR VOLTAGE INVERTER

Изобретение относитс к области преобразовани посто нного тока в пе- ременный многофазный и может быть использовано дл питани различных пот ребителей электроэнергии, например электродвигателей.This invention relates to the field of converting direct current to alternating multiphase alternating current and can be used to power various electrical power consumers, such as electric motors.

Известны схемы трехфазных тиристорных инверторов Tl и 2.Known circuits of three-phase thyristor inverters Tl and 2.

Наиболее близким вл етс трехфазный тиристорный инвертор, содержащий в каждой фазной группе два последовательно соединенных через коммутирующий дроссель со средней точкой основных тиристора, подключенных к выводам дл источника питани , а также коммутирующие конденсаторы и обратный диодный мост 2 .The closest is a three-phase thyristor inverter containing in each phase group two connected in series through a switching choke with the midpoint of the main thyristor connected to the terminals for the power supply, as well as switching capacitors and a reverse diode bridge 2.

Недостаток известной схемы - значительные коммутационные потери энергии .A disadvantage of the known scheme is significant switching energy losses.

Целью изобретен 1Я вл етс уменьшение коммутационных потерь.The purpose of the invented IP is to reduce switching losses.

Цель достигаетс тем, что в инверторе , между положительным выводом источника питани и общей точкой катодов обратных диодов, а также между отрицательным выводом источника питани и общей точкой анодов обратных диодов включены обмотки дополнительного коммутирующего дроссел с общим магнитопроводом, причем выводы обмоток подключены так, что их магнитные потоки взаимно компенсируютс .The goal is achieved by the fact that in the inverter, between the positive output of the power source and the common point of the cathodes of the reverse diodes, as well as between the negative output of the power source and the common point of the anodes of the return diodes, the windings of the additional switching droplet with the common magnetic conductor are connected, and the windings are connected so that magnetic fluxes cancel each other out.

На чертеже приведена принципиаль10 на схема предлагаемого инвертора напр жени .The drawing shows a principle 10 on the circuit of the proposed voltage inverter.

Инвертор содержит шесть тиристоров 1-6 и три коммутирующих дроссел 7, 8, 9, образующие три чейки. К The inverter contains six thyristors 1-6 and three commutating chokes 7, 8, 9, forming three cells. TO

15 средним точкам чеек подключены коммутирующие конденсаторы 10,.11, 12, которые могут быть соединены в звезду или в треугольник, или по мостовой схеме. К этим же средним точкам 15 middle points of the cells are connected switching capacitors 10, .11, 12, which can be connected in a star or in a triangle, or on a bridge circuit. To the same middle points

Claims

20 cells connect the load and reverse diodes. One of the windings of the additional droplet is connected between the positive pole of the power supply and the common point of the cathodes of diodes 13, 15, I, and the other between the negative pole of the power source and the common point of the anodes of the diodes 16, 18, The ends of the windings of the chokes 19 are connected so that the magnetic fields The windings are directed opposite. The inverter works as follows. Let the thyristor 1 conduct the current; The switching capacitors 10, 11 are charged and have the polarity shown in the drawing; With the switching on of the thyristor 2, the energy stored in the capacitors passes into the choke 7) after which this energy returns; capacitors that are recharged and acquire the opposite polarity. The reverse diode k in this case does not prevent the return of energy from the throttles 7, since for a sharp increase in current in one of the windings, for example in the lower one, the throttle 19 requires a similar increase in the current in the other (in the upper) winding. Since the analogous process of switching in other cells is not yet taking place at this time, choke 19 prevents the circuit from closing along the circuit: choke 7 — thyristor 2 — diode I — choke 7. At the same time, when Hai-switch decreases, reverse diodes prevent an increase in voltage zheny at the exit. In this case, the diodes from both the even and odd groups are opened, and the current can freely increase sharply through the windings of the throttles 19. Thus, in this inverter, with a high inductance of the commutating chokes 7, 8, 9, the current in their 4 currents under the action of switching processes increases slightly. Thyristors and reverse diodes will not be uselessly loaded. All this will lead to a reduction in switching losses. This technical solution eliminates the need for an aid to TehbHbix thyristors, which results in simplification of the device. Since the magnetic fields of the windings are directed oppositely, there is no magnetic bias of the core .. A core without a gap can be used in this device. Invention Three-phase thyristor voltage inverter, containing in each phase group two connected in series via commutation (throttle with midpoint of main thyristor connected to terminals for power supply, as well as switching capacitors connected to output terminals, and reverse diode bridge, different so that, in order to reduce switching energy losses, between the positive output of the power source and the common point of the cathodes of the reverse diodes, as well as between the negative output of the source The power source and the common point of the anodes of the reverse diodes are connected to the windings of an additional commutating throttle with a common magnetic core, and the terminals of the windings are connected so that the magnetic fluxes of the windings are mutually compensated. Sources of information taken into account during the examination 1. English patent No. H 2 F 23 .iD7.63.

2. USSR author's certificate №, cl. G 05 F 3/08, 01/26/68.

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