SU788311A1

SU788311A1 - Method of obtaining predetermined shape of inverter output voltage curve

Info

Publication number: SU788311A1
Application number: SU701524949A
Authority: SU
Inventors: Владимир Самойлович Моин; Николай Николаевич Лаптев; Игорь Александрович Войтович; Виталий Александрович Цишевский
Original assignee: Предприятие П/Я М-5374
Priority date: 1970-10-06
Filing date: 1970-10-06
Publication date: 1980-12-15

Description

Изобретение относится к преобразовательной технике, в частности к инверторам, используемым в качестве вторичных источников питания- систем автоматики и электропривода, преобразующим постоянное напряжение в переменное напряжение с формой, близкой к синусоидальной.The invention relates to a conversion technique, in particular to inverters used as secondary power sources — automation and electric drive systems that convert direct voltage to alternating voltage with a shape close to sinusoidal.

Для получения многоступенчатой формы выходного напряжения инверторы выполняют в виде нескольких инверторных ячеек, выходные напряжения которых суммируют.To obtain a multistage form of the output voltage, the inverters are made in the form of several inverter cells, the output voltages of which are added up.

Известен способ формирования напряжения , при котором на выходе указанных ячеек формируют прямоугольные напряжения, а сигналы управления ячейками взаимосдвигают по фазе.A known method of generating voltage, in which the output of these cells form a rectangular voltage, and the control signals of the cells are offset in phase.

В таком инверторе ячейки имеют выходные трансформаторы, установленная мощность которых превышает мощность нагрузки. Кроме того, количество ячеек при таком способе формирования достаточно велико, например для получения трехступенчатой формы требуется шесть ячеек, а для шестиступенчатой формы - двенадцать ячеек [11 и [2].In such an inverter, the cells have output transformers whose installed power exceeds the load power. In addition, the number of cells with this method of formation is large enough, for example, to obtain a three-stage form, six cells are required, and for a six-step form, twelve cells [11 and [2].

Известен также способ формирования многоступенчатого напряжения на выходе инвертора, состоящего из нескольких инверторных ячеек, при котором на выходе каждой ячейки формируют прямоугольное напряжение с паузами на нуле различной длительности [з].There is also a method of forming a multi-stage voltage at the output of an inverter, consisting of several inverter cells, in which a rectangular voltage is generated at the output of each cell with pauses at zero of various durations [h].

По отношению к известным способам при этом уменьшается установленная мощность трансформаторов и ключей ячеек, так как исключается встречное включение выходов ячеек и возникающая при этом бесполезная возвратная передача энергии из цепи нагрузки в источник питания. Однако так же, как и в предыдущем случае, количество ячеек велико, что увеличивает массу и снижает КПД инвертора.In relation to the known methods, the installed power of the transformers and the cell switches is reduced, since the on-board switching of the cell outputs and the resulting useless return transmission of energy from the load circuit to the power source are eliminated. However, as in the previous case, the number of cells is large, which increases the mass and reduces the efficiency of the inverter.

Цель изобретения - снижение массо-габаритных показателей и повышение КПД.The purpose of the invention is the reduction of mass and overall indicators and increased efficiency.

Цель достигается тем, что для получения заданной формы кривой выходного напряжения инвертора, симметричной относительно середины полупериода, при котором на выходе основной и К дополнительных инверторных ячеек формируют двухполярные симметричные относительно середины полупе риода прямоугольные импульсы с паузой на нуле с каждой стороны полу периода, имеющие длительность соотдетственно с1_ос,_и.'иэл.град., где К - номер дополнительной ячейки, а затем суммируют эти импульсы, произ? водят формирование дополнительных пауз на нуле в каждом полупериоде импульсов на выходе дополнительных ячеек, причем каждая из этих пауз имеет длительность (¾ эл.град. и расположена на расстоянии эл.град. от соответствующего фронта указанного импульса до ближайшей границы паузы. В конкретном случае трехступенчатой формы выходного напряжения используется одна дополнительная ячейка, а углы d-ocH^P-i ⁼ 7Г принимаются •равными 30 эл.град, , а угол cL ι равным нулю, в случае шестиступенчатой формы выходного напряжения используются?· i'pii дополнительные ячейки, а углы прзнимйются равными ~ 7) 2= (f2,~1 - эл. гр ад. _{с (} -- p.j — 'З 4 — 3 0 эл.град., 1¾¾--45 эл.град., а угол d₍равным нулю.The goal is achieved in that in order to obtain a given shape of the output voltage curve of the inverter, symmetrical with respect to the middle of the half-cycle, at the output of the main and K additional inverter cells, bipolar rectangular pulses are generated, symmetrical with respect to the middle of the half-cycle, with a pause at zero on each side of the half-period, having a duration respectively, with 1 _os , _and .'iel.grad., where K is the number of the additional cell, and then these pulses are summed, lead to the formation of additional pauses at zero in each half-cycle of pulses at the output of additional cells, each of these pauses having a duration (¾ electric grad. and located at a distance of electric grad. from the corresponding front of the specified pulse to the nearest border of the pause. In the specific case, there is a three-stage output voltage form is used, one additional cell, and corners d-ocH ^ Pi ⁼ 7D taken • el.grad equal to 30, and cL ι angle equal to zero, if the output voltage six forms are used? · i'pii additionally th cell, and equal angles prznimyyutsya ~ 7) 2 = (f2, ~ 1 - e t al _{c (-..} pj - 'H 4 -. 3 0 el.grad, 1¾¾ - 45 el.grad as well. angle d ₍ equal to zero.

данный способ позволяет уменьшить количество ячеек по отношению к известному способу за счет многократного на протяжении полупериода участия выходного напряжения каждой дополнительной ячейки в формировании выходного напряжения инвертора. Тем самым снижается масса и габариты и повышается КПД инвертора.This method allows to reduce the number of cells in relation to the known method due to the multiple during the half-period of participation of the output voltage of each additional cell in the formation of the output voltage of the inverter. This reduces the weight and dimensions and increases the efficiency of the inverter.

На фиг. 1 (а, б) показана схема, реализующая предлагаемый способ при формировании трехступенчатого напряжения, ч диаграммы основных напряжений этой схемы; на фиг.. 2 (а, б) то «о, жри формировании шестиступенчатого напряжения.In FIG. 1 (a, b) shows a circuit that implements the proposed method when forming a three-stage voltage, h diagram of the main stresses of this circuit; in Fig. 2 (a, b) then "oh, eat the formation of a six-step voltage.

Инвертор (фиг. 1, а) содержит основную мостовую инверторную ячейку на управляемых ключах (транзисторах, тиристорах и т.п.) 1-4 и дополнительную полумостовую инверторную ячейку ,на ключах 5 и 6. На выход моста, образованного ключами 1,2,5,6, включен трансформатор 7, вторичная обмотка которого соединена последовательно с выходом основного моста, образуя цепь для питания -нагрузки 8.The inverter (Fig. 1, a) contains the main bridge inverter cell on controlled keys (transistors, thyristors, etc.) 1-4 and an additional half-bridge inverter cell, on keys 5 and 6. To the output of the bridge formed by keys 1,2 , 5,6, a transformer 7 is turned on, the secondary winding of which is connected in series with the output of the main bridge, forming a circuit for supplying load 8.

г.!Т',-'^ти получают сигналы управления UxjriP -i’ ^иУЛ|-.г^;- U-i_fly.ъ > имеющие вид,показавшей на фиг'. 1,6, и формируемые в устройстве, управления (на фиг. 1 не показано), содержащем задающий генератор и распределитель импульсов любого известного вида. При коммутации ключей на выходе основного моста образуется прямоугольное двухполярное напряжение Uc с паузами на нуле длительностью cZocB.⁼ 30 эл.град. с каждой стороны полупериода, а на выходе трансформатора 7 - напряжение 11( с дополнительными паузами на нуле длительностью (1'4 - 30 эл.град. на расстоянии 30 эл.град. Суммарное •напряжение на нагрузке имеет трехступенчатую форму с коэффициентом.g! T ', -' ^t and receive control signals UxjriP -i ' ^and UL | -.g ^; - Ui _fl y.b> having the view shown in FIG. 1.6, and formed in the device, control (in Fig. 1 is not shown), containing a master oscillator and a pulse distributor of any known type. When the keys are switched, a rectangular bipolar voltage Uc is formed at the output of the main bridge with pauses at zero with duration cZocB. ⁼ 30 electric city on each side of the half-cycle, and at the output of the transformer 7 - voltage 11 (with additional pauses at zero duration (1'4 - 30 electrical degrees at a distance of 30 electrical degrees. Total • the voltage at the load has a three-stage form with a coefficient.

искажений 16% и содержит высшие гармоники только с порядковым номером м = 12η ± 1, где η = 1,2,3,... и т.д.distortion 16% and contains higher harmonics only with serial number m = 12η ± 1, where η = 1,2,3, ... etc.

Аналогичным путем может быть выполнен инвертор с любым числом ступеней в форме выходного напряжения. Например, на фиг. 2 показан инвертор с шестиступенчатой формой Uh? содержащий основную мостовую инверторную ячейку на ключах 9-12 и три дополнительных полумостовых инверторных ячеек на ключах 13-18,на выходе которых включены трансформаторы 19-21. Распределение импульсов управления, подаваемых на ключи инвертора, выполнено таким образом, чтобы на вторичных обмотках трансформаторов 19-21 формировались напряжения U.^ , U и U-j, показанные на фиг. 26. На выходе инвертора формируется шестиступенчатое напряжение = U_o+ Uρ + 0^ + U-j (фиг. 2,6), имеющее коэффициент искажений 7,5% и содержащее высшие гармоники только с порядковым номером m = 2 4 η .- 1 , где η = 1,2,3··· и т.д., т.е. с наиниэшей 25-ой гармоникой .In an analogous way, an inverter with any number of stages in the form of an output voltage can be made. For example, in FIG. 2 shows an inverter with a six-speed form Uh? containing the main bridge inverter cell on keys 9-12 and three additional half-bridge inverter cells on keys 13-18, at the output of which transformers 19-21 are included. The distribution of control pulses supplied to the inverter keys is made in such a way that voltages U. ^, U and Uj shown in FIG. 26. A six-step voltage = U _o + Uρ + 0 ^ + Uj is formed at the inverter output (Fig. 2.6), having a distortion coefficient of 7.5% and containing higher harmonics with only serial number m = 2 4 η .- 1, where η = 1,2,3 ···, etc., i.e. with the 25th harmonic.

Преимущество предлагаемого спо-1 соба состоит в уменьшении количества дополнительных ячеек, а именно: для формирования трехступенчатой кривой (фиг. 1,6) при известном способе требуется две дополнительные ячейки, а при предлагаемом способеодна; для формирования шестиступенчатой кривой (фиг. .2,б) требуется соответственно пять и три дополнительных ячейки. Если уровень выходного напряжения позволяет выполнить основную ячейку . бестрансформаторной, как показано на ’фиг. 1,а и на фиг. 2.а, то при предлагаемом способе уменьшается расчетная мощность выходных трансформаторов дополнительных ячеек по отношению к известным способам в 2-5 раз. Это видно из фиг. 1,6 и фиг. 2₍б при сопоставлении заштрихованной (проходящей через трансформгиоры), и незаштрихованной (бестрансформаторной) площади кривой выходного напряжения.The advantage of the proposed method-1 soba is to reduce the number of additional cells, namely: for the formation of a three-stage curve (Fig. 1,6) with the known method requires two additional cells, and with the proposed method one; for the formation of a six-step curve (Fig.. 2, b), five and three additional cells are required, respectively. If the output voltage level allows you to run the main cell. transformerless, as shown in 'FIG. 1a and FIG. 2.a, then, with the proposed method, the design power of the output transformers of the additional cells is reduced 2-5 times with respect to the known methods. This can be seen from FIG. 1.6 and FIG. 2 ₍ b when comparing the hatched (passing through transformers) and the unshaded (transformerless) area of the output voltage curve.

Вследствие’указанных преимуществ уменьшается масса и габариты инвертор;-! и повышается КПД.Due to these advantages, the weight and dimensions of the inverter are reduced; -! and efficiency increases.

Claims

The invention relates to a conversion technique, in particular, to inverters used as secondary power sources — automation and electric drive systems, which convert a constant voltage to an alternating voltage with a form that is close to sinusoidal. To obtain a multistage output voltage, the inverters are made in the form of several inverter cells, the output voltages of which are summed. There is a known voltage shaping method in which rectangular voltages are formed at the output of yakan cells and cell control signals are mutually shifted in phase. In this inverter, the output transformers have a set power exceeding the load power. In addition, the number of cells with such a method is not large enough, for example, to obtain a three-step form, the cell length is required, and for the six-step form, twelve cells i and G21. A method of forming a multi-stage voltage at the inverter cell consisting of several inverter cells is also known. in which, at the output of each cell, a rectangular voltage is formed with pauses at zero of different duration h. With respect to the known methods, the installed power of the transformers and cell switches is reduced, since counter-switching of the cell outputs is avoided and the return transfer of energy from the load circuit to the power source arising in this case. However, just as in the previous case, the number of cells is large, which increases the mass and reduces the efficiency of the inverter. The purpose of the invention is to reduce the mass-dimensional indicators and increase the efficiency. The goal is achieved in order to obtain a given shape of the output voltage curve of the inverter, symmetrical with respect to the center of the half-rim, in which two-polar symmetrical with respect to the center of the half-period are formed at the output of the main and K additional inverter cells rectangular pulses with a pause at zero on each side of the half period, having a duration, respectively. el.grad., where K is the number of the additional cell, and then these pulses are summed, which causes the formation of additional pauses at zero in each half-period of the pulses at the output of the additional cells, and each of these pauses has a duration (L electr. and at a distance of Jf el.grad from the corresponding front of the specified pulse to the nearest pause boundary. In the specific case of the three-step output voltage, one additional cell is used, and the angles. T P - equal to 30 eh. grad, and the angle cj is equal to zero, In the case of six nachy form; l vpmhdnogo naprikzheny use;: f-} / 1-1, the main cells, and the angles; hp: -and {and; .. 1 are SHOCKED, p. .., (1os.n./R-T-1 - 30 el., .45 el.grad., And angle o, j equal to iuchu.This method allows to reduce the number of cells in relation to lime ot.iy way due to the repeated part of the output voltage each additional cell in the form of the blood voltage and the output voltage of the inverter.This very same time, the mass and ga.baryty and increase the efficiency of the inverter. Fig. 1 (a, b) shows a scheme that implements the proposed method in the formation of a three-stage papre;:;; , п Д1с1 ра№.1г.г main; ; Papr NII g- | oy scheyy; in Fig. 2 (a, b) that ve.,: oh formforming; h c1 1-step palpjecci. Inzag: the torus (fkg. 1, a) contains the main bridge inverter cell of the ynpaBJjrr-MHX keys (transistors, triggers, etc.) 1-4 and additionally a half-bridge invariant cell, at blocks 5 and 6. At the output of the bridge, about 1, 2, 5, and 6 keys, including a transformer 7, the secondary winding of which is coadministered successively with the output of the main bridge, which is used for the load of 8. KI, -7H, tu 1e; rm signal; 1 Zio uprailensh - 1 V..o; i ij .. ,,, p.-i, having the form, in kg gzag-i. fi1. 1.6, and the generated control device (on phpg. 1 is not shown), which contains the master oscillator and the distributor of impulses of God ... godly type. When switching keys at the output of the main bridge, a rectangular two-pole voltage Uo is formed with pauses at zero with a duration of d-ocH.- 30 zl.grad. on each side of the half cycle, and the output of the transformer 7 is voltage U with additional pauses pausing the duration PJ.I - 30 zl.grad. at a distance of 7 30 e. The total load HcnuJtxeHue has a three-stage forg with a coefficient. sayings of 16% and contains higher garonics with only a serial number of 12n ± 1, where n 1,2,3, ... etc. In the same way, an inverter can be made with any number of steps in the form of output voltage. For example, in FIG. Figure 2 shows an inverter with an unistep form of a voltage regulator, containing the main bridge inverter cell on the keys 9-12 and three additional half-bridge inverter checks: on the keys 13-18, the output of which includes transformers 19-21. The distribution of control pulses applied to the inverter keys is designed so that the secondary windings of the transformers 19-21 form the voltages U,, U / and U-j shown in FIG. 2b A six-speed and + U2, + ui voltage UU (Fig. 2.0) is formed at the output of the inverter, having a distortion factor of 7.5% and containing harmonics with the order number m 2k n, - 1, where n 1, 2,3 ..- etc., i.e. with E ainizshaya 25th harmonic. The advantage of the proposed cno-i. Sob is to reduce the number of additional cells, namely: for a three-step curve curve (Fig. 1.6) with the known method, two additional cells are required, and with the proposed method, one is needed; to form a six-step curve (fig. 2.0), respectively, five and three additional cells are required. If the output voltage level allows the main cell to be executed. bestransformator, as shown in FIG. 1, and in FIG. 2, a, then with the proposed method, the calculated power of the output transformers of the additional cells in relation to the known methods is reduced by 2--5 times. This is evident from FIG. 1.6 and FIG. 2.6 when comparing the hatched (passing through transformers) and un hatched (transformerless) area of the output voltage curve. As a result of these advantages, the weight and dimensions of the inverter are reduced and the efficiency is increased. Claim 1, A method for obtaining a predetermined shape of an inverter output voltage curve that is symmetric about the middle of a half period, with icOTOpoM at the output of the main and K additional inverter cells, form two-polar rectangular half-period symmetric pulses with a half-period side, having a half-period, having a duration - respectively, and about {. (el.grad., where K is the number of the additional cell, and then these pulses are summed up, characterized in that, with

in order to reduce mass-size parameters and increase efficiency, at the output of additional cells, in a half-period, at least one additional pair of pauses is formed at zero, each of which has a duration (.h. and is located at a distance of e. degrees from the corresponding front of the specified pulse to the nearest border pause.

2. Method POP.1, characterized in that, in order to obtain a three-step approximating sinusoid curve, the output voltage of the inverter is set to K l ,, otoCHf 30 el.grad.

3. The method according to claim 1, characterized in that /, to obtain a six-step sine curve approximating the output voltage or inverter curve, set,,, eta. T-jf 15 el.,

ctocH 30 el.grad., 45 ep.grady

Sources of information taken into account in the examination

1. USSR author's certificate o 124157, cl. H 02 M 7/48, 1961.

2. Bedford B. et al. Theories of autonomous inverters. Energy, 1969, p. 203, fig. 6-22.

3. In the same place 238, fig. 7-23.

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