WO1988007413A1 - Procede permettant de produire une tension cc variable - Google Patents

Procede permettant de produire une tension cc variable Download PDF

Info

Publication number
WO1988007413A1
WO1988007413A1 PCT/SE1988/000159 SE8800159W WO8807413A1 WO 1988007413 A1 WO1988007413 A1 WO 1988007413A1 SE 8800159 W SE8800159 W SE 8800159W WO 8807413 A1 WO8807413 A1 WO 8807413A1
Authority
WO
WIPO (PCT)
Prior art keywords
voltage
transformer
variable
khz
primary winding
Prior art date
Application number
PCT/SE1988/000159
Other languages
English (en)
Inventor
Per Anders Gustav Ranstad
Original Assignee
Fläkt Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fläkt Ab filed Critical Fläkt Ab
Publication of WO1988007413A1 publication Critical patent/WO1988007413A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/337—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only in push-pull configuration

Definitions

  • the present invention relates generaXlly to a method for generating a variable high d.c. voltage from an alternating voltage, preferably at mains frequency, said d.c. voltage being applied to the electrodes of an electrostatic precip ⁇ itator whose voltage exceeds 30 kV and whose power require- ment is normally from 1 to 100 k .
  • the present invention relates particularly, but not exclu ⁇ sively, to a method of this kind in which the alternating voltage is first converted to a first d.c. voltage and this first d.c. voltage is applied pulsewise to the primary winding of a transformer, such as to obtain a high alternating voltage in the secondary winding of the trans ⁇ former, after which this high alternating voltage is con ⁇ verted to a high d.c. voltage, which constitutes said variable high d.c. voltage.
  • the present invention in addition to enabling a gener ⁇ ated high d.c. voltage across the electrodes of an electrostatic precipitator to be controlled in a predetermined manner or to maintain the d.c. voltage constant at a given level, the present invention also en ⁇ ables a d.c. voltage to be varied in time quickly, in a desired manner.
  • the present invention has been primarily devised for generating practically any desired variable high d.c. volt ⁇ age such as to " ' be applied to the electrodes of an electro ⁇ static precipitator, thereby to enable time control of the • voltage between the electrodes.
  • a high d.c. voltage can be generated, e.g. for supplying the electrodes of an electrostatic precipitator, from, e.g., a mains voltage, by first step- ping up the voltage through a transformer and then recti ⁇ fying said voltage.
  • this high d.c. voltage can be con ⁇ trolled manually by switching the transformer or with the aid of power controlling devices, such as transductors or thyristors, connected in the primary circuit.
  • power controlling devices such as transductors or thyristors
  • the use of power control devices enables slow variations of the d.c. voltage to be obtained -when desired, for instance in order to adapt the d.c. voltage to variations in operating con- ditions.
  • the dimensions of the transformer are contingent on the frequency used for the applied voltage, and that a higher frequency enables a reduction in the weight of the transformer. It is also known that the eddy current losses increase markedl at high frequencies.
  • the core of the transformer norm ly consists of a number of thin plates. In practice, plates ha a thickness of 0.3 mm can be used up to 500 Hz. The thinnest p capable of being handled can be used up to frequencies of between 1 and 3 kHz.
  • the pulse frequency of the d.c. voltage can be increased. to 3 kHz.
  • a further technical problem resides in the need to control the d.c. voltage level in an electrostatic precipitator.
  • a particular technical problem in this art is one of en ⁇ abling the voltage in an electrostatic precipitator to be varied with a time constant which is much shorter than the period of the mains voltage used.
  • Another technical problem is one of being able to interrupt quickly the voltage supply to an electrostatic precipi ⁇ tator in the event of flashover between the precipitator electrodes, and therewith minimize the time during which the precipitator is inactive as a result of gas discharge (arc).
  • a further technical problem resides in the ability of quickly supplying energy to the electrostatic precipitator subsequent to extinguishing the gas discharge caused by flashover.
  • Another technical problem is one of realizing that problems of insulation and problems of capacitive storage of energy in a transformer can be greatly reduced by magnetizing the transformer solely in one direction.
  • a further technical problem resides in the realization that the transformer can be demagnetized by a purely passive circuit, even somewhat quicker than the time during which the active magnetization takes place.
  • a further technical problem resides in the realization that those gaps which occur in the voltage supply to a secondary loa as a result of demagnetizing the transformer passively can be filled with two transformers working in "counterphase".
  • a further technical problem is one of realizing that the power input to an electrostatic precipitator can be ad- vantageously controlled by supplying a high voltage trans ⁇ former with a pulse voltage having a high and fixed fre ⁇ quency, and by varying solely the pulse time.
  • a qualified technical problem in this regard is one of realizing that with a high frequency, pulse-width-modulated pri ary voltage the rectified secondary voltage can be caused to closely resemble a desired, more slowly varying course.
  • a further technical problem resides in the provision, with the aid of simple components, of a method which utilizes a pulse frequency of between 20 kHz and 200 kHz with regard to the d.c. voltage to be applied to the primary winding of the transformer, and therewith to create conditions, in the absence of excessive losses, such that the d.c. voltage occurring between the electrodes of an electrostatic pre ⁇ cipitator can be caused to vary in time in accordance with a predetermined desired pattern or in any desired manner.
  • a further technical problem is one of realizing that when practicing the aforementioned method, in which a configured d.c. voltage is applied pulsewise to the pri ⁇ mary winding of the transformer, the frequency can be selected advantageously between 30 kHz and 70 kHz.
  • the present invention relates to a method for producing a variable or constant high d.c. voltage having a d.c. volt ⁇ age level or value in excess of 30 kV,from an alternating voltage, preferably at mains frequency, such as 50 Hz or 60 Hz.
  • the inventive method is based on the known technique of converting said alternating voltage to a d.c. voltage, optionally subsequent to transforming-up the voltage, and of applying this d.c. voltage pulse-wise to the primary winding of a transformer, and by rectifying the output voltage from the secondary winding of the transformer, this output voltage constituting said variable d.c. voltage. It is proposed in accordance with the invention that this pulsewise supply of d.c. voltage to the primary winding of the transformer is effected at a frequency of between 20 kHz and 200kHz, particularly between 30 kHz and 70 kHz, and preferably at about 50 kHz.
  • the transformer is mag ⁇ netized solely in one direction, by supplying to the primary winding a pulsed d.c. voltage of solely one polar ⁇ ity.
  • variable d.c. voltage is obtain by connecting two transformers in parallel and by activating said transformers alternately.
  • the primary winding of the transformer is supplied with a pulsed d.c. voltage of fixed frequency and the de ⁇ sired variation ih the variable d.c. voltage is obtained by varying the time during which respective d.c. voltage pulses are supplied to the primary winding.
  • the transformer magnetizing time is controlled by active components, such as transistors or thyristors, whereas demagnetization of the transformer is effected with the aid of passive circuit elements, such as diodes for exam ⁇ ple.
  • variable d.c. voltage can be advantageously obtained, by connecting two trans ⁇ formers or transformer windings in parallel and by switching-i them alternatively.
  • ADVANTAGES The advantages primarily characteristic of a method according to the present invention which can be used to particular advantage for varying the high d.c. voltage applied to the electrodes of an electrostatic precipitator reside in the provision of conditions which enable the dimensions of the transformer to be substantially reduced while still achieving improved and more rapid control of the voltage between the precipitator electrodes while enabling the electrode voltage to be maintained with practically any desired time variation.
  • Figure 1 is an electric circuit diagram of a known device for generating a variable high d.c. voltage
  • Figure 2 illustrates a known arrangement in the upper part of an electrostatic precipitator and operating with a device according to Figure 1;
  • Figure 3 is a block schematic of a device constructed in accordance with the present invention.
  • Figure 4 illustrates an arrangement in the upper part of an electrostatic precipitator in which the inventive device of Figure 3 is used;
  • FIG. 5 is a circuit diagram of the inventive device shown in Figure 3;
  • Figure 6 illustrates examples of pulse-width-modulated d.c. voltage pulses applied to the primary winding of the transformer
  • Figure 7 is a perspective view of a proposed transformer core
  • Figure 8 is a perspective view of part of one secondary winding of the transformer.
  • Figure 1 shows the circuitry of a device for generating a variable, high d.c. voltage having a value which, normally exceeds 30 kV and which appears on a conductor 2 «
  • the device is supplied with energy in form of alternating voltage, preferably having a mains frequency of 50 Hz, supplied on a conductor 1.
  • the conductor 2 is connected to corona discharge electrodes in an electrostatic precipitator 10.'
  • Figure 1 corresponds to Figure 6 of US Patent Specification Serial No 4 486 704, and the reader is therefore referred to this patent specification for a better understanding of the circuit illustrated in Figure 1 and the manner in which the d.c. voltage across the electrodes of an electrostatic precipitator is controlled.
  • each precipitator section normally requires a control cabinet or panel 12 by means of which the d.c. voltage supplied to the electrostatic precipitator can be controlled and regulated, therewith to enable the d.c. voltage to be varied in a predetermined manner.
  • Figure 3 is a block schematic illustrating a device con ⁇ structed in accordance with the invention.
  • the device illustrated in Figure 3 comprises a circuit 3 which converts alternating voltage to a d.c. voltage,and a unit 4 which is operative in pulsating the d.c. voltage to the primary winding Tl of the transformer and which is controlled over a conductor 5.
  • the inventive device further includes a circuit 6 which is connected to the secondary winding (T2) of the transformer T, in which circuit 6 the generated a.c. high voltage is converted to a high d.c. voltage, and the output signal of which cir ⁇ cuit 6 is preferably passed through a filter 7 and consti ⁇ tutes said variable high d.c. voltage on the conductor 2, this high d.c. voltage being supplied to the electrostatic precipitator.
  • the unit 4 which supplies the occurrent d.c. voltage pulsewise to the primary wind ⁇ ing Tl is constructed to impart to the d.c. voltage pulses supplied to the primary winding Tl of the transformer a pulse frequency of between 20 kHz and 200 kHz.
  • the d.c. voltage vari ⁇ ation lies within the range of 30 kV to 120 kV, preferably within the range of from 50 kV to 90 kV.
  • the unit 4 is constructed so as to supply the d.c. voltage pulses to the primary winding Tl of the transformer at a pulse frequency of between 20 kHz and 100 kHz, suitably between 30 kHz and 70 kHz, and preferably at a pulse fre ⁇ quency around 50 kHz.
  • the transformer preferably has the confuguration illustrated in greater detail in Figures 7 and 8.
  • the reference 15 identifies an arrangement having a casing 15a which houses the requisite transformer in the bottom half thereof, the construction of which transformer is described in more detail hereinafter, and in the top half thereof houses the requisite control circuits for controlling switches or electrical contacts "A" and "B" in the desired manner.
  • a comparison between Figures.2 and 4 will show the substan ⁇ tial simplification and the reduction in external measure ⁇ ments, and therewith the saving in weight, afforded by the present invention.
  • Figure 5 illustrates an arrangement, or device, which is constructed in accordance with the principles of the pres ⁇ ent invention and which comprises an input three-phase cable 1 which is connected to a circuit 3 of known con- struction for converting the nominal alternating voltage to a d.c. voltage.
  • the alternating voltage supply on the conductors 1 is a three-phase 380 V alternating voltage having a mains frequency of 50 Hz, there will appear on the output conductors 3a of the circuit 3 a d.c. voltage of approximately 500 V, which is supplied to a circuit 4.
  • the circuit 4 includes two switch contacts "A" which, when activated simultaneously, effect a transfer of the d.c. voltage on conductors 3a pulsewise to the primary winding 23 of a first transformer 22.
  • the control circuits which control the switches "A" are of a known kind and have not therefore been shown in detail here for the sake of simplicity.
  • the switches may be arranged to be activated at for instance, frequencies from 20 kHz to 200 kHz. In the illustrated example the switches are activated at a frequency of 50 kHz.
  • the supply time of each pulse is variable, so as to be able to vary the level of the generated variable d.c. voltage within the electrostatic precipitator 10.
  • the circuit, or unit, 4 also includes two switches "B" which, similarly to the switches "A", are intended, when activated simultaneously, to connect the d.c. voltage present on the conductor 3a to the primary winding 27 of a second transformer 26 within a time section other than that in which the switches "A" connect voltage to the primary winding 23.
  • the pulses are also in this case applied at a frequency of 50 kHz and the duration of these pulses can also be regulated or controlled.
  • the illustrated circuit 4 also includes, in accordance with the invention, four diodes, of which two, referenced 20 and
  • the diodes 20, 21 and 24, 25 function as demagnetizing diodes, therewith enabling the transformer to be demagnet ⁇ ized by a current passed through the diodes subsequent to the supply of a d.c. voltage pulse through the primary winding of the transformer.
  • the circuit or unit 4 can be controlled by a control data-processor 30 in a manner which will enable the duration of the d.c. voltage pulse to be varied up to the half-period of the frequency concerned, this control data-processor being of a known kind and therefore not described here.
  • the magnetic core of the transformer is to be de-magnetized during the remaining part of the frequency period.
  • the unit 4 is so controlled by the data processor or control unit 30, through the intermediary of switches "A" and "B", as to effect a pulse width modulation of the individual, sequential pulses, therewith to form a time-variable, high d.c. voltage, which exhibits pulses having a pre-determined variation in time.
  • This latter applies in particular to those cases when the electrostatic pre ⁇ cipitator is to be supplied with a d.c. voltage which shall be superimposed with one or more pulses.
  • Figure 6 is a diagrammatic illustration of d.c. voltage pulses a_ and b which, via the switches "A" and “B", are supplied to respective transformers 22 and 26 during each half time-period, therewith transferring maximum energy to the electrostatic precipitator 10 connected to the point referenced 31, such as to achieve the theoretical maximum d.c. voltage.
  • Figure 6 also illustrates pulses a_' and b 1 which are sup ⁇ plied to the transformers 22 and 26 and the pulse-width- modulation of which is selected so that voltage is trans ⁇ ferred to the primary windings of respective transformers during solely 25 % of the time period. It is obvious that a lower voltage will then lie across the electrodes of the electrostatic precipitator.
  • the lowermost row in Figure 6 illustrates pulses a_" which have mutually different pulse widths in time and which will,, wi t h this distribution in time, successively raise the voltage level in t he electrostatic precipitator. It should be observed in this regard that although in Figure 6 the pulse modulation of the two signals a_ and b has been shown to be equal, this need not necessarily be the case. It will also be understood that the voltage in the electrostatic precipitator 31 can be varied accurately in ' dependence on the prevailing pulse width modulation of the mutually sequential pulses.
  • each transformer comprises two, preferably similar windings 28a and 28b (respectively 29a and 29b), each of which is connected up ⁇ stream and downstream of its respective diode 33 and 34 (33a and 34a) and which has an intermediate diode 35 (35a) connected therebetween, These diodes are connected in- a manner to control the current in the two .windings for current flow in solely one direction.
  • a respective terminal point of each secondary winding is earthed in the system through a respective diode 34 and 34a, and that the two remaining terminal points of the secondary windings 28a, 29a of respective transformers are connected to a common 5 point 36 through their respective diodes 33, 33a.
  • A. diode 37 and a capacitor 38 are earthed in parallel from the common point 36, across the two series-connected wind ⁇ ings and the three series-connected diodes, the diode 37 functioning as a freewheel diode.
  • the system also includes an output choke 39 which is located between the common point 36 and the electrodes (not shown) of the electro ⁇ static precipitator 10.
  • each diode symbol may represent, in practice, a plurality of diode units connected together in series.
  • Figures 7 and 8 illustrated suitable transformer T for the inventive function, where part of the secondary winding of the transformer comprises an electrically con ⁇ ductive layer 40 applied to a circuit card 41.
  • the layer 40 is applied in the form of a "plane spiral" on one side of the card. Seventeen turns of the full secondary winding are located on each circuit card.
  • circuit cards are arranged in side-by-side relationship (41, 41a) such as to form one part of the secondary winding of the transformer, for instance the winding part referenced 28a.
  • the primary winding 23 of the transformer 22 may comprise one or two turns, which are positioned between the two secondary windings 28a, 28b, of which only one part of one secondary winding is shown in Figure 8.
  • circuit cards 41, 41a, and all remaining circuit cards are arranged to embrace and be embraced by a transformer core 43, and each circuit card is positioned at a distance 44 from an adjacent circuit card, this distance preferably being from 1-2 mm.
  • Both circuit cards and transformer cores are surrounded by cooling oil, which also covers the requisite diodes or diode units.
  • diodes such as diodes 45, 46
  • diodes 45, 46 are connected also between mutually adjacent circuit cards. In this way, a diode will connect each cir ⁇ cuit card with another circuit card andtherewith reduce the influence of the capacitance against the core.
  • the primary winding 23 is intended to be placed centrally on the transverse limb 43a ' of the transformer, with a secondary winding 28a on the left hand side and a secondary winding 28b on the right hand side.
  • Requisite diodes 33, 34 and 35 may be mounted adjacent the transformer on a plate not shown.
  • the transformer core may be constructed from a ferrite material and may comprise eight standardized U-shaped sec ⁇ tions.
  • a first two such U-shaped sections 50 and 51 are placed ad- jacent one another and a second two such U-shaped sections 52 and 53 are placed adjacent one another, such that the mutually adjacent limbs of said sections form one half of the illustrated transformer limb 43.
  • the remaining four transformer sections are positioned in mirror image to the aforesaid four sections. Apertures formed centrally in respective circuit cards 41 and 41a are intended to accommodate the limb 43a of the transformer.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Electrostatic Separation (AREA)

Abstract

Procédé permettant de générer à partir d'une tension alternative (1), de préférence de fréquence du réseau, une tension cc variable (3) qui est appliquée aux électrodes d'un appareil électrostatique de précipitation avec un niveau de tension dépassant 30 kV. La tension alternative (1) est convertie (3) en tension cc, facultativement après la transformation de la tension cc, celle-ci (via les commutateurs ''A'' et ''B'') étant envoyée par impulsions à l'enroulement primaire (23) d'un transformateur (22), la tension de sortie de l'enroulement secondaire (28a, 28b) du transformateur étant redressée (33, 35, 34), et constituant la tension cc variable. L'alimentation de la tension envoyée par impulsions de la tension cc à l'enroulement primaire du tranformateur (via les commutateur ''A'' et ''B'') est réalisée à une fréquence située entre 20 kHz and 200 kHz.
PCT/SE1988/000159 1987-04-01 1988-03-30 Procede permettant de produire une tension cc variable WO1988007413A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8701367A SE8701367L (sv) 1987-04-01 1987-04-01 Foerfarande foer att alstra en varierbar likspaenning
SE8701367-8 1987-04-01

Publications (1)

Publication Number Publication Date
WO1988007413A1 true WO1988007413A1 (fr) 1988-10-06

Family

ID=20368069

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1988/000159 WO1988007413A1 (fr) 1987-04-01 1988-03-30 Procede permettant de produire une tension cc variable

Country Status (3)

Country Link
AU (1) AU1599488A (fr)
SE (1) SE8701367L (fr)
WO (1) WO1988007413A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5575836A (en) * 1993-12-28 1996-11-19 Mitsubishi Jukogyo Kabushiki Kaisha Electric dust collector
US5639294A (en) * 1993-01-29 1997-06-17 Abb Flakt Ab Method for controlling the power supply to an electrostatic precipitator
EP1870995A1 (fr) * 2006-06-23 2007-12-26 ALSTOM Technology Ltd Alimentation électrique pour un précipitateur électrostatique
US11338302B1 (en) * 2020-10-30 2022-05-24 Hubei University Of Technology Apparatus and test method for simulating spark discharge of high-voltage electrostatic precipitator

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3562623A (en) * 1968-07-16 1971-02-09 Hughes Aircraft Co Circuit for reducing stray capacity effects in transformer windings
EP0058777A2 (fr) * 1981-02-25 1982-09-01 Blaupunkt-Werke GmbH Convertisseur de tension pour un récepteur de télévision
GB2100525A (en) * 1978-03-23 1982-12-22 Tokyo Shibaura Electric Co Gly-back transformer
EP0203270A2 (fr) * 1985-02-28 1986-12-03 SELENIA SPAZIO S.p.A. Convertisseur courant continu-courant continu comportant un onduleur à modulation d'impulsion produisant une tension de forme quasi-trapézoidale et un rectificateur à faible perte pour produire une tension de sortie continue
EP0206160A1 (fr) * 1985-06-24 1986-12-30 Metallgesellschaft Ag Alimentation de courant pour filtre électrostatique

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3562623A (en) * 1968-07-16 1971-02-09 Hughes Aircraft Co Circuit for reducing stray capacity effects in transformer windings
GB2100525A (en) * 1978-03-23 1982-12-22 Tokyo Shibaura Electric Co Gly-back transformer
EP0058777A2 (fr) * 1981-02-25 1982-09-01 Blaupunkt-Werke GmbH Convertisseur de tension pour un récepteur de télévision
EP0203270A2 (fr) * 1985-02-28 1986-12-03 SELENIA SPAZIO S.p.A. Convertisseur courant continu-courant continu comportant un onduleur à modulation d'impulsion produisant une tension de forme quasi-trapézoidale et un rectificateur à faible perte pour produire une tension de sortie continue
EP0206160A1 (fr) * 1985-06-24 1986-12-30 Metallgesellschaft Ag Alimentation de courant pour filtre électrostatique

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5639294A (en) * 1993-01-29 1997-06-17 Abb Flakt Ab Method for controlling the power supply to an electrostatic precipitator
US5575836A (en) * 1993-12-28 1996-11-19 Mitsubishi Jukogyo Kabushiki Kaisha Electric dust collector
EP1870995A1 (fr) * 2006-06-23 2007-12-26 ALSTOM Technology Ltd Alimentation électrique pour un précipitateur électrostatique
WO2007147844A2 (fr) * 2006-06-23 2007-12-27 Alstom Technology Ltd Bloc d'alimentation pour précipitateur électrostatique
WO2007147844A3 (fr) * 2006-06-23 2008-02-21 Alstom Technology Ltd Bloc d'alimentation pour précipitateur électrostatique
US7701732B2 (en) 2006-06-23 2010-04-20 Alstom Technology Ltd. Power supply for electrostatic precipitator
US11338302B1 (en) * 2020-10-30 2022-05-24 Hubei University Of Technology Apparatus and test method for simulating spark discharge of high-voltage electrostatic precipitator

Also Published As

Publication number Publication date
AU1599488A (en) 1988-11-02
SE8701367D0 (sv) 1987-04-01
SE8701367L (sv) 1988-10-02

Similar Documents

Publication Publication Date Title
US3745440A (en) Electrical inverter-rectifier circuit and inductor apparatus therefor
EP0417771B1 (fr) Circuit générateur d'impulsion à haute tension et précipitateur électrostatique utilisant un tel circuit
EP0055903B1 (fr) Alimentation en courant électrique
US5718662A (en) Apparatus for the magnetic stimulation of cells or tissue
EP0386261A1 (fr) Transformateur electrostatique
DE3271885D1 (en) Pulse circuits for generating short duration high power pulses
DE3922665C2 (fr)
US3846695A (en) Series-parallel dual switching regulator for use with a variety of line voltages
WO1988007413A1 (fr) Procede permettant de produire une tension cc variable
US3530357A (en) Current rectifying system for high voltage
SE9100595D0 (sv) Energifritt kraftaggregat
CA1285987C (fr) Alimentation a decoupage
US3526824A (en) Current transformer device for high voltage
EP0352287A1 (fr) Convertisseur de tension
US3764889A (en) Sequencer for a dual switching regulator
MY103686A (en) High voltage dc generator with reduced ringing and voltage fluctuation
CA1050099A (fr) Alimentation haute frequence pour generateur d'effet couronne
US3303409A (en) Current interrupting network for controlled rectifiers
SU1697061A1 (ru) Регулируемый преобразователь переменного напр жени в переменное
US4437026A (en) Apparatus for electrode current control in linear MHD generators
SU1173506A1 (ru) Устройство дл питани электрофильтра
SU1483568A1 (ru) Многоканальный преобразователь дл зар да емкостных накопителей
SU1525775A1 (ru) Выходной блок много чейкового преобразовател
RU1795533C (ru) Мостовой инвертор
US3829755A (en) Sequencer for a multiple switching regulator

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU BB BG BR DK FI HU JP KP KR LK MC MG MW NO RO SD SU US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE BJ CF CG CH CM DE FR GA GB IT LU ML MR NL SE SN TD TG