WO2007003474A2 - Procede de commande pour convertisseur a deux etages - Google Patents

Procede de commande pour convertisseur a deux etages Download PDF

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Publication number
WO2007003474A2
WO2007003474A2 PCT/EP2006/062697 EP2006062697W WO2007003474A2 WO 2007003474 A2 WO2007003474 A2 WO 2007003474A2 EP 2006062697 W EP2006062697 W EP 2006062697W WO 2007003474 A2 WO2007003474 A2 WO 2007003474A2
Authority
WO
WIPO (PCT)
Prior art keywords
signal
reference signal
switching element
converter
pulse width
Prior art date
Application number
PCT/EP2006/062697
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German (de)
English (en)
Other versions
WO2007003474A3 (fr
Inventor
Jalal Hallak
Original Assignee
Siemens Ag Österreich
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 Siemens Ag Österreich filed Critical Siemens Ag Österreich
Publication of WO2007003474A2 publication Critical patent/WO2007003474A2/fr
Publication of WO2007003474A3 publication Critical patent/WO2007003474A3/fr

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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
    • H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
    • H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
    • H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
    • H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
    • H02M3/1582—Buck-boost converters

Definitions

  • the invention relates to a control method for a converter, which comprises a buck converter with a first switching element and a boost converter with a second switching element, wherein the switching elements are switched on and off by a control device by means of a first and a second pulse width modulated drive signal. Furthermore, the invention relates to an arrangement for carrying out the method.
  • PFC Power Factor Correction
  • Switching power supplies an input current in the form of short pulses from the grid. This causes undesired distortions of a sinusoidal mains voltage and disturbing harmonics.
  • switching power supplies for power factor correction are connected to a mains voltage with a high-buck converter.
  • boost converter an intermediate circuit voltage is regulated to the peak value of the mains voltage and reduced to a lower value in a downstream step-down converter (see FIG. 1).
  • a method for power factor correction by means of boosters is given in WO1998009368. In this method with linear pulse width modulation and constant switching period, no detection of the input voltage is necessary, which instead of three only two feedback loops are required.
  • the method causes after rectification of an AC voltage, the output of a DC link voltage with sinusoidal current drain.
  • a downstream buck converter can be used to reduce to a desired DC output voltage.
  • boost converter and buck converter for converting a rectified higher AC voltage into a lower DC voltage with power factor correction can also be applied in the opposite way.
  • a low DC voltage of an alternative DC voltage source can be converted to a pulsating, higher DC voltage, with the maximum value of the output voltage being above and the minimum value of the output voltage being below the input voltage value.
  • the buck and boosters are alternately active during a period.
  • the buck converter In the sections where the pulsating output DC voltage is below the input voltage, the buck converter is active and in the sections where the pulsating DC output voltage is above the input voltage, the step-up is active.
  • the transitions between active buck and boost are critical.
  • the invention is therefore based on the object to provide a method and an arrangement with which a high and a buck converter can be operated in the manner described.
  • a control method for a converter which comprises a buck converter with a first switching element and a boost converter with a second switching element, wherein the switching elements are switched on and off by a control device by means of a first and a second pulse width modulated drive signal, wherein a second reference signal is formed from a first reference signal and a difference value, a comparison signal for both reference signals is determined, and wherein the comparison signal and the first reference signal, the first drive signal is modulated and wherein the comparison signal and the second reference signal, the second drive signal is modulated.
  • An arrangement for carrying out the method comprises a step-down converter with a first switching element connected in series with a step-up converter with a second switching element.
  • the switching elements are connected to a control device, in the means for presetting the second reference signal, formed from the first reference signal and the difference value and means for determining the comparison signal for both reference signals and means for modulating the first drive signal from the comparison signal and the first reference signal and for modulating the second drive signal from the
  • Comparison signal and the second reference signal are provided.
  • the amplitude of a reference signal minus a correction value is specified as the difference value.
  • the comparison signal can be used unchanged for both pulse width modulations, ie it requires no gain, attenuation or other adjustment of the comparison signal for one of the two pulse width modulations.
  • the correction value compensates for the voltage drop in the chokes, diodes and switching elements and causes both boosters and step-downs in the transition region during the passage of the output voltage through the input voltage value are active and no dips in the output voltage curve occur.
  • the first reference signal is generated with zero as the lower limit value by means of a signal generator and with a
  • Peak detection unit is generated from a peak signal and that the second reference signal is formed from the first reference signal by adding or subtracting the peak signal minus the correction value.
  • Peak detection unit and an adder necessary.
  • changes in the first reference signal due to tolerances of the signal generator or due to thermal changes are automatically compensated.
  • Another advantageous embodiment of the invention provides that by means of a signal generator, the first reference signal and an amplitude detection unit, an amplitude signal is generated and that the second
  • the minimum value of the first reference signal then does not have to be zero, since the amplitude is detected here as the difference between the maximum value and the minimum value of the first reference signal.
  • the comparison signal is generated by means of a control element from a predetermined desired output voltage and an actual output voltage in such a way that with increasing comparison signal initially overlapping with the first reference signal and thus increase the turn-on of the first switching element until if the comparison signal matches the peak values of the first reference signal, the first switching element remains switched on and that the second switching element begins to clock starting from the coincidence of the rising comparison signal with the peak values of the first reference signal minus the correction value and the turn-on times increase with the comparison signal increasing further.
  • the controller of the converter switches the switching elements of the high and the buck in the way that the actual output voltage of this target output voltage follows.
  • the correction value is specified in such a way that in a region in which intersect the first reference signal and the second reference signal alternately with the comparison signal, the actual output voltage continuously passes through the value of the input voltage. This prevents unevenness in the course of the output voltage from occurring when the output voltage passes through the current input voltage value. Depending on the voltage drops in the components used, the output voltage would sag momentarily when passing through the input voltage value without the correction value.
  • control device comprises a signal generator which generates the first reference signal and is connected to a first pulse width modulation unit, an addition unit and a peak detection unit for generating the peak value signal and that the addition unit is connected to the peak detection unit and the output side is connected to a second pulse width modulation unit and that the converter is connected with its output voltage to a control unit which supplies the comparison signal with a predetermined output voltage and is connected on the output side to the first pulse width modulation unit and to the second pulse width modulation unit and that the first pulse width modulation unit the first switching element and the second pulse width modulation unit is connected to the second switching element.
  • Fig. 1 Converter operated according to the prior art
  • Fig. 2 converter with Hochsetzer and downstream
  • Step-down converter Fig. 3 Converter with step-down converter and downstream circuit
  • FIG. 4 Pulse width modulation with a comparison signal V smaller than the input voltage value Ue
  • FIG. 5 Pulse width modulation with a comparison signal V equal to the input voltage value Ue
  • FIG. 6 Pulse width modulation with a comparison signal V greater than the input voltage value Ue
  • Fig. 7 Pulse width modulation with correction value X.
  • FIG. 1 shows a converter with a step-up converter and a downstream step-down converter in the manner used according to the prior art for power factor correction.
  • the boost converter consisting of a switching element SH, a choke LH and a diode DH is connected to an input capacitor Ce to a pulsating input voltage Ue as a rectified AC voltage.
  • a DC link capacitor Cz then the constant DC link voltage Uz is applied, the value of which corresponds to the peak value of the input voltage Ue.
  • the buck converter connected to the intermediate circuit voltage Uz comprises a switching element ST, a diode DT and a choke LT and supplies via an output capacitor Ca a constant output voltage Ua whose value is less than the peak value of the input voltage Ue.
  • the switching elements SH and ST are controlled by a controller with pulse width modulation PWM.
  • the controller switches the switching elements SH and ST on and off in such a way that the shape of the current consumption corresponds to the sinusoidal form of the input voltage Ue.
  • FIG. 2 shows an advantageous embodiment of the present invention. Except for the control of the switching elements SH and ST, the arrangement corresponds to that shown in Figure 1.
  • the input voltage Ue is assumed to be, for example, a constant DC voltage.
  • the boost converter causes by an inventive control of the switching element SH, that in the DC link capacitor Cz an intermediate circuit voltage Uz with constant sections and intermediate positive semi-sinusoidal voltage groups is applied.
  • the constant sections of the intermediate circuit voltage curve have the value of the input voltage Ue, and the maximum values of the semi-sinusoidal voltage points reach approximately twice the value.
  • Switching element ST in the buck converter causes the constant sections in the intermediate circuit voltage curve are reduced in such a way that the output voltage Ua is a pulsed DC voltage, the one SoIl output voltage Usoll with exemplary semi-sinusoidal
  • the drive is based on the target output voltage Usoll and the measured actual output voltage Ua, which in one
  • Controller element I / A are compared and from which a comparison signal V is generated at the output of the controller element I / O.
  • This comparison signal V is supplied both to the first pulse width modulation unit PWM1 for the switching element ST in the step-down converter and to the second pulse width modulation unit PMW2 for the switching element SH in the step-up converter.
  • a signal generator G generates a sawtooth signal which is supplied as a reference signal to the first pulse width modulation unit PWM1.
  • a peak signal is generated from the sawtooth signal, which is then added to the sawtooth signal.
  • the resulting sum signal is supplied as a second reference signal of the second pulse width modulation unit PWM2.
  • the first pulse width modulation unit PWM1 generates from the first reference signal and the comparison signal V a drive signal Al for switching the switching element ST of the buck converter on and off.
  • the second pulse width modulation unit PWM2 generates from the second reference signal and the comparison signal V a drive signal A2 for switching the switching element SH of the boost converter on and off.
  • FIG. 3 shows a converter in which a step-down converter is connected downstream of a step-down converter, wherein both switching elements ST and SH are again driven according to the invention in an advantageous manner.
  • the buck converter with the switching element ST and the diode DT are connected via the input capacitor Ce to an input voltage Ue. Behind it is connected in series with a common inductor L, the boost converter with the switching element SH and the diode DH.
  • the arrangement then supplies an output voltage as a pulsed DC voltage which follows a desired output voltage Usoll and whose minimum value is below the current one
  • Input voltage value (for example, zero) and the maximum value Ü is above the current input voltage value.
  • the elements of the control of the two switching elements ST and SH correspond to those shown in FIG.
  • the first pulse width modulation unit PWM1 again supplies the drive signal Al for the switching element ST of the buck converter
  • the second pulse width modulation unit PWM2 controls the switching element SH of the boost converter with the drive signal A2.
  • FIG. 4 shows the signal curves for the two pulse width modulations. In the diagrams, the signal values are plotted over time. The top diagram shows the first reference signal
  • Saw number signal for the pulse width modulation unit PWMl between the value zero and a first peak corresponds to the value of the amplitude A-PWMl.
  • Pulse width modulation unit PWM2 The amplitude of the second reference signal A-PWM2 thus corresponds to the amplitude of the first reference signal A-PWMl.
  • This second reference signal is generated in a simple manner by addition of the first reference signal with a peak value signal which is formed from the peak value of the first reference signal.
  • the drawn course of the comparison signal V is, for example, approximately 3/4 of the first peak value, so that it intersects with the course of the first reference signal.
  • the intersections between the comparison signal and the reference signal result in accordance with the pulse width modulation, the on and off times for the switching element associated with the reference signal.
  • the drive signal A2 results as a continuous zero signal, i. the assigned switching element SH always remains switched off.
  • the first reference signal results in the intersections of the ascending course sections with the comparison signal off pulses and for the intersections of the falling
  • FIG. 5 shows the same progress diagrams as in FIG. 4, with the difference that the comparison signal V corresponds to the first peak signal.
  • the comparison signal V thus touches the upper peaks of the first reference signal and the lower peaks of the second reference signal, which causes the drive signal Al to turn on continuously and the drive signal A2 signals continuous switching off.
  • the switching element ST of the buck converter thus remains switched on, without clocking, and the switching element SH of the Hochsetzers remains switched off without clocking.
  • the current value of the output voltage Ua thus corresponds to the current input voltage value, in which case the input voltage Ue is assumed as a constant DC voltage.
  • FIG. 6 shows the progress diagrams with a further increase
  • Comparison signal V shown.
  • the comparison signal V has only points of intersection with the second reference signal, wherein again with the drive signal A2 at an intersection point with rising reference signal switch off and at an intersection with falling reference signal switching on of the switching element SH of the Hochsetzers is signaled.
  • the drive signal Al further causes the switching element ST remains turned on without clocking.
  • FIG. 7 shows the course of the signals with correction value X.
  • the course of the first reference signal is unchanged.
  • the second reference signal is shifted by the correction value X in the direction of the abscissa, so that the minimum values of the second reference signal by the correction value X are lower than the maximum values of the first reference signal.
  • the comparison signal is constant on average between the minimum values of the second reference signal and the maximum values of the first reference signal, ie it intersects both reference signals in this control state.
  • the intersections of a rising reference signal with the course of the comparison signal causes shutdown again and the intersections of a descending reference signal with the course of the comparison signal causes switching on again one of the switching elements SH and ST.
  • the two control signals A1 and A2 initially signalise switching on.
  • the comparison signal first separates the second reference signal in the further chronological sequence, the drive signal A2 drops to zero and thus signals the switching element SH of the boost converter to switch off. Then, the comparison signal intersects the first reference signal, whereby also the first drive signal Al drops to zero and signals the switching element ST of the buck converter off. Shortly thereafter, the comparison signal simultaneously intersects the falling edges of both reference signals, whereby both control signals Al and A2 jump to the switch-on pulse value and thus cause switching on of both switching elements SH and ST. This sequence repeats periodically.
  • the magnitude of the correction value X depends on the voltage drops in the components of the converter and is then selected correctly if the output voltage curve when passing through the input voltage value has no discontinuities. If the correction value X is too low, the output voltage curve drops briefly in the range of the input voltage value. If the correction value X is too large, it briefly increases.
  • the comparison signal V is drawn parallel to the abscissa because the clock frequency of the switching elements is very high in relation to the frequency with which the output voltage changes (for example with the frequency of a supply network). In the illustrated time period, the comparison signal V thus remains approximately constant, but in fact it changes with the frequency of the predetermined desired output voltage and thus undergoes the states shown in Figures 4 to 7.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)

Abstract

L'invention concerne un procédé de commande pour un convertisseur, comprenant un module abaisseur de tension avec un premier élément de commutation (ST) et un module élévateur de tension avec un second élément de commutation (SH). Les éléments de commutation (ST, SH) sont enclenchés et arrêtés par un dispositif de commutation au moyen d'un premier et d'un second signal d'attaque (A1, A2) à impulsions modulées en largeur. Un signal de référence est formé à partir d'un premier signal de référence et d'une valeur différentielle. Un signal de comparaison (V) est obtenu pour les deux signaux de référence et le premier signé d'attaque (A1) est modulé avec le signal de comparaison (V) et le premier signal de référence. Le second signal d'attaque (A2) est modulé avec le signal de comparaison (V) et le second signal de référence. L'invention permet d'assurer une commande aisée, coordonnée dans le temps, des éléments de commutation (ST-SH) dans des modules élévateurs de tension et dans des modules abaisseurs de tension.
PCT/EP2006/062697 2005-06-30 2006-05-30 Procede de commande pour convertisseur a deux etages WO2007003474A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102005030599.7 2005-06-30
DE200510030599 DE102005030599A1 (de) 2005-06-30 2005-06-30 Steuerungsverfahren für zweistufige Konverter

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WO2007003474A2 true WO2007003474A2 (fr) 2007-01-11
WO2007003474A3 WO2007003474A3 (fr) 2007-06-28

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI405395B (zh) * 2009-03-30 2013-08-11 Yuan Henh Technology Ltd 串兩級隔離之直流轉換裝置
CN107248816A (zh) * 2017-08-11 2017-10-13 株洲宏达微电子科技有限公司 基于传统Buck‑Boost拓扑的一种新型变换器电路

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT505446B1 (de) * 2007-06-19 2009-08-15 Siemens Ag Oesterreich Analog dividierer
AT505801B1 (de) * 2007-09-20 2012-09-15 Siemens Ag Verfahren zum betrieb eines elektronisch gesteuerten wechselrichters
EP2479878B1 (fr) 2011-01-25 2016-07-20 Siemens Aktiengesellschaft Procédé destiné au réglage d'un convertisseur abaisseur-élévateur
CN103163930A (zh) * 2013-04-07 2013-06-19 北京机械设备研究所 一种级联变换器的电压闭环稳定控制电路
DE102016000207A1 (de) * 2016-01-11 2017-07-13 Finepower Gmbh Verfahren zum Betrieb eines Buck-Boost-Konverters

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3104965A1 (de) * 1981-02-12 1982-08-26 Brown, Boveri & Cie Ag, 6800 Mannheim Gleichstrompulswandler
DE4306070C1 (de) * 1993-02-26 1994-10-06 Siemens Nixdorf Inf Syst Schaltungsanordnung zum Ansteuern der Schaltglieder eines Auf-Abwärts-Spannungswandlers
US6166527A (en) * 2000-03-27 2000-12-26 Linear Technology Corporation Control circuit and method for maintaining high efficiency in a buck-boost switching regulator
US20030052654A1 (en) * 2001-08-07 2003-03-20 Yoshihide Kanakubo Boosting and step-down switching regulator controlling circuit and boosting and step-down switching regulator for use in the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3104965A1 (de) * 1981-02-12 1982-08-26 Brown, Boveri & Cie Ag, 6800 Mannheim Gleichstrompulswandler
DE4306070C1 (de) * 1993-02-26 1994-10-06 Siemens Nixdorf Inf Syst Schaltungsanordnung zum Ansteuern der Schaltglieder eines Auf-Abwärts-Spannungswandlers
US6166527A (en) * 2000-03-27 2000-12-26 Linear Technology Corporation Control circuit and method for maintaining high efficiency in a buck-boost switching regulator
US20030052654A1 (en) * 2001-08-07 2003-03-20 Yoshihide Kanakubo Boosting and step-down switching regulator controlling circuit and boosting and step-down switching regulator for use in the same

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
JALADE,J. MARPINARD,J.C VALENTIN, M.: "dc/ac high power cell structure improves sine generator performance" AEROSPACE AND ELECTRONICS SYSTEMS, IEEE TRANSACTIONS ON, Bd. AES-17, Mai 1981 (1981-05), Seiten 373-379, XP002428500 *
SEN P C ET AL: "A new DC-to-AC inverter with dynamic robust performance" TENCON '98. 1998 IEEE REGION 10 INTERNATIONAL CONFERENCE ON GLOBAL CONNECTIVITY IN ENERGY, COMPUTER, COMMUNICATION AND CONTROL NEW DELHI, INDIA 17-19 DEC. 1998, PISCATAWAY, NJ, USA,IEEE, US, Bd. 2, 17. Dezember 1998 (1998-12-17), Seiten 387-390, XP010355530 ISBN: 0-7803-4886-9 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI405395B (zh) * 2009-03-30 2013-08-11 Yuan Henh Technology Ltd 串兩級隔離之直流轉換裝置
CN107248816A (zh) * 2017-08-11 2017-10-13 株洲宏达微电子科技有限公司 基于传统Buck‑Boost拓扑的一种新型变换器电路

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DE102005030599A1 (de) 2007-01-11
WO2007003474A3 (fr) 2007-06-28

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