(19)
(11)EP 2 456 060 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
09.09.2020 Bulletin 2020/37

(21)Application number: 10799682.9

(22)Date of filing:  27.05.2010
(51)International Patent Classification (IPC): 
H02M 5/458(2006.01)
H02M 7/48(2007.01)
H02M 1/36(2007.01)
H02M 7/06(2006.01)
H02M 1/32(2007.01)
(86)International application number:
PCT/JP2010/058995
(87)International publication number:
WO 2011/007620 (20.01.2011 Gazette  2011/03)

(54)

POWER CONVERTER CIRCUIT

STROMWANDLERSCHALTUNG

CIRCUIT CONVERTISSEUR DE PUISSANCE


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

(30)Priority: 15.07.2009 JP 2009166378

(43)Date of publication of application:
23.05.2012 Bulletin 2012/21

(73)Proprietor: Daikin Industries, Ltd.
Osaka-shi, Osaka 530-8323 (JP)

(72)Inventors:
  • SEKIMOTO, Morimitsu
    Kusatsu-shi, Shiga 525-8526 (JP)
  • MAEDA, Toshiyuki
    Kusatsu-shi, Shiga 525-8526 (JP)

(74)Representative: Hoffmann Eitle 
Patent- und Rechtsanwälte PartmbB Arabellastraße 30
81925 München
81925 München (DE)


(56)References cited: : 
EP-A1- 1 643 631
JP-A- H1 052 051
JP-A- 2005 020 836
JP-U- S6 358 899
US-A- 6 002 103
US-A1- 2007 177 407
US-A1- 2008 211 449
DE-A1- 10 162 246
JP-A- 2001 333 573
JP-A- 2005 020 836
JP-U- 63 058 899
US-A1- 2007 013 332
US-A1- 2008 130 183
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    TECHNICAL FIELD OF THE INVENTION



    [0001] The present invention relates to a power converter circuit provided between an alternating-current power supply and a load.

    BACKGROUND ART



    [0002] In US 2007/0013332 A1 there is described a variable speed drive comprising a main rectifier module including thyristors to power a main continuous bus from an external power network, an inverter module delivering a variable control voltage to an electric motor from the main bus, auxiliary rectifier module connected to the external power network, an electronic control unit controlling the thyristors, a powering module supplying the control unit from the auxiliary rectifier module and from the main rectifier module. A switching device controlled by the control unit is used to disconnect the powering module and the auxiliary rectifier module.

    [0003] Further, a variety of power converter circuits provided between an alternating-current power supply and a load to respectively supply the load with a predetermined alternating-electric current have been developed. Out of them, downsizing of inverters and inverters without capacitors aimed for a cost-cut have been suggested ("IMPROVED POWER FACTOR RECTIFIER CIRCUIT FOR INVERTER CONTROLLED PM MOTOR" written by Isao Takahashi announced at 2000 Technical Meeting 4-149 of the Institute of Electrical Engineers of Japan (held in March, 2000), page 1591). As shown in FIG. 6, an inverter 40 without capacitor comprises: a diode group 16; a DC section 18; and an inverter 20. Further, a relay S for power shutdown is provided at a point between a power supply 12 and the diode group 16 to prevent electric energy from inflowing into the DC section 18 when the inverter 20 stops.

    [0004] The diode group 16 is a diode bridge consisting of four diodes. The diode group 16 performs full-wave rectification for an output of the alternating-current power supply 12 and outputs to a power supply line 22 of an upper arm and a power supply line 24 of a lower arm. The DC section 18 comprises: a reactor Lin inserted into the power supply lines 22 and 24; and a smoothing capacitor Cdc provided at a point between the power supply lines 22 and 24. The DC section 18 does not include a large capacity of an electrolytic capacitor. The smoothing capacitor Cdc of the DC section 18 typically has a capacity of about 20 µF, which is about 0.01 to 0.02 time as large as the electrolytic capacitor. The inverter 20 includes a switching power element (transistor) and a reflux diode, and outputs alternating-current power to the load 14.

    [0005] Direct current voltage fluctuates widely even though the inflow energy into the DC section 18 is small because the smoothing capacitor Cdc of the DC section 18 is small in capacity. Further, examples of the state in which direct current voltage tends to rise include the time when LC resonance of a reactor Lin caused by power supply activation/power strain and a smoothing capacitor Cdc is generated, and the time when inductance energy reflux of the load 14 is performed when the inverter stops.

    [0006] As shown in FIG. 7, an inverter 40b without capacitor equipped with an energy-absorbing circuit 28 in the DC section 18 has been suggested as a measure to prevent the aforementioned overvoltage (JP 2005-20836 A). In the energy-absorbing circuit 28, a diode Ds, a resistor Rs, an electrolytic capacitor Cs are series-connected to one another between the power supply lines 22 and 24. Since the electrolytic capacitor Cs is also charged as well as the smoothing capacitor Cdc, the apparent capacity of the smoothing capacitor Cdc grows. Moreover, the resistor Rs controls the passing of a charging current through the electrolytic capacitor CS. Accordingly, a potential difference Vdc of both edges of the smoothing capacitor Cdc becomes smaller, which leads to prevent overvoltage.

    [0007] The charging voltage of the electrolytic capacitor Cs is almost uniformly smoothed. The electrolytic capacitor Cs can be used as a power supply of a circuit for driving at a fixed voltage. Further, the inverter 40b without capacitor is equipped with a control circuit 26 arranged and configured to control the switching power element and the relay S. Consequently, it has been suggested in JP 2005-20836 A that the electrolytic capacitor Cs is used as a power supply of the control circuit 26.

    [0008] However, in the case where the relay S is Off, no voltage is applied to the energy-absorbing circuit 28 provided in the DC section 18. The electrolytic capacitor Cs to be used as a power supply of the control circuit 26 is not charged, so that the control circuit 26 is not driven. As a result, the relay S cannot be switched on and the inverter 40b without capacitor remains stacked.

    [0009] The Japanese patent document JPH1052051 discloses an AC/AC electric power converter circuit comprising an electromagnetic switch connected to an AC input power supply, a rectifier converter, a DC circuit, a DC circuit capacitor, an inverter, connected to the DC circuit, a diode rectifier bridge connected between the electromagnetic switch and the AC input power supply.

    SUMMARY OF THE INVENTION



    [0010] It is an object of the present invention to provide a power converter circuit capable of suppressing overvoltage of a DC section and generating a power supply for a control circuit.

    MEANS FOR SOLVING THE PROBLEMS



    [0011] The summary of the present invention is described as follows:
    In a first preferred aspect of the present invention, there is provided a power converter circuit according to claim 1 which comprises: a diode group including a plurality of diodes arranged to rectify an output voltage of an alternating-current power supply; a relay provided at a point located closer to the alternating-current power supply than the diode group; a DC section where an output voltage of the diode group is applied; and an inverter arranged to output a three-phase alternating-electric current to a three-phase load. The DC section has a maximum pulse voltage twice as great as a minimum pulse voltage thereof. The DC section includes an energy-absorbing circuit being a series circuit between a diode and an electrolytic capacitor. A rectifying circuit is directly connected to a point closer to the alternating-current power supply than the relay and is connected to the electrolytic capacitor to provide a pathway arranged to apply the output voltage of the alternating-current power supply from the alternating-current power supply to the electrolytic capacitor via a rectifying circuit, not via the relay, when the relay is off.

    [0012] According to the present invention, the power converter circuit generally rectifies at a diode bridge and charges the electrolytic capacitor provided on a subsequent stage. When the relay provided on a former stage of the diode bridge is Off, the power converter circuit charges the electrolytic capacitor from the power supply via the rectifying circuit, not via the relay.

    [0013] In a second preferred aspect, the power converter circuit according to the present invention further includes a control circuit arranged and configured to control the inverter using a charging voltage of the electrolytic capacitor as a power supply. The control circuit operates using the charging voltage of the electrolytic capacitor as a power supply.

    [0014] In a third preferred aspect, the power converter circuit according to the present invention further includes a control circuit arranged and configured to switch the relay on/off using the charging voltage of the electrolytic capacitor as a power supply. The electrolytic capacitor is usually used as a power supply of the control circuit because the electrolytic capacitor is charged even when the relay is off.
    is cancelled.

    [0015] In a fourth preferred aspect of the power converter circuit according to the present invention,
    the energy-absorbing circuit (28) further comprises a resistor (Rs) and is a series circuit among the diode (Ds), a resistor (Rs), and the electrolytic capacitor (Cs); and the rectifying circuit (30) is connected to either point of connection between the diode (Ds) and resistor (Rs) or the resistor (Rs) and the electrolytic capacitor (Cs).

    [0016] In a fifth preferred aspect of the power converter circuit, the pathway is arranged to apply the output voltage of the alternating-current power supply (12) to the electrolytic capacitor (Cs) via the rectifying circuit (30) includes a resistor (Rss).

    [0017] In a sixth preferred aspect of the power converter circuit, the rectifying circuit is either a full-wave rectifying circuit or a half-wave rectifying circuit. Full-wave rectification or half-wave rectification is performed to apply a voltage to the electrolytic capacitor.

    [0018] In a seventh preferred aspect of the power converter circuit of the present invention, the electrolytic capacitor is an electrolytic capacitor of the energy-absorbing circuit provided on the subsequent stage of the diode bridge. The charging voltage of the electrolytic capacitor in the energy-absorbing circuit is virtually constantly smoothed and becomes a power supply of the control circuit that needs a fixed voltage.

    EFFECTS OF THE INVENTION



    [0019] According to the present invention, it is possible to apply a voltage from the power supply to the electrolytic capacitor via the rectifying circuit, not via the relay. This makes it possible to charge the electrolytic capacitor even when the relay is Off. Even if the relay is Off, the control circuit using the electrolytic capacitor as a power supply is driven, so that the relay is turned on/off. It is possible for the power converter circuit to prevent overvoltage because of having an electrolytic capacitor.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0020] 

    FIG. 1 is a schematic diagram of a power converter circuit according to the present invention;

    FIG. 2 is a schematic diagram in which a resistor of the power converter circuit shown in FIG. 1 is shared;

    FIG. 3 is a schematic diagram in which a resistor value of the power converter circuit shown in FIG. 1 is adjusted;

    FIG. 4 is a schematic diagram of a power converter circuit according to the present invention using a full-wave rectifying circuit;

    FIG. 5 is a schematic diagram in which a resistor value of the power converter circuit shown in FIG. 4 is adjusted;

    FIG. 6 is a schematic diagram of a conventional inverter without capacitor.

    FIG. 7 is a schematic diagram of an energy-absorbing circuit in the inverter without capacitor shown in FIG. 6.


    DESCRIPTION OF THE PREFERRED EMBODIMENTS



    [0021] The power converter circuit of the present invention will now be described by referring to the accompanying drawings. The power converter circuit described below is an inverter without capacitor.

    [0022] As shown in FIG. 1, a power converter circuit 10 is used at a point between a power supply 12 and a load 14 and outputs predetermined alternating-current power to the load 14. The power supply 12 shown in FIG. 1 is a single-phase power supply. The load 14 is a three-phase load and an example thereof is a three-phase motor.

    [0023] The power converter circuit 10 includes a relay S, a diode group 16, a DC section 18, and an inverter 20. The diode group 16, the DC section 18, and the inverter 20 are connected to one another by a first power supply line 22 of an upper arm and a second power supply line 24 of a lower arm. Further, the power converter circuit 10 includes a control circuit 26 arranged and configured to drive and control the relay S and the inverter 20.

    [0024] The diode group 16 is a diode bridge consisting of four diodes. The diode group 16 performs full-wave rectification to output a direct current voltage to the first power supply line 22 and the second power supply line 24. The second power supply line 24 is lower than the first power supply line 22 in voltage.

    [0025] The DC section 18, in which the output of direct current voltage is applied to the subsequent stage of the diode group 16, includes a reactor Lin and a smoothing capacitor Cdc for smoothing the direct current voltage outputted from the diode group 16. The reactor Lin is inserted in the first power supply line 22 and is connected to a point between the power supply lines 22 and 24. As shown in FIG. 1, the reactor Lin and the smoothing capacitor Cdc are designed to be general smoothing circuits. As described in the prior art, the smoothing capacitor has a low volume.

    [0026] The DC section 18 has a maximum pulse voltage twice as great as a minimum pulse voltage thereof. And the DC section 18 includes an energy-absorbing circuit 28 as a measure thereof. The energy-absorbing circuit 28 is parallel-connected to the smoothing capacitor Cdc. The energy-absorbing circuit 28 is series-connected to the diode Ds, the resistor Rs, and the electrolytic capacitor Cs in this order from the first power supply line 22 side. In the diode Ds, an anode is connected to the first power supply line 22. The smoothing capacitor Cdc is series-connected to the electrolytic capacitor Cs, resulting in an increase in the apparent capacity of the smoothing capacitor Cdc. The resistor Rs has functions to control a rapid rise in voltage. Overvoltage of the voltage placed between both ends Vdc in the smoothing capacitor Cdc is suppressed by the energy-absorbing circuit 28. Further, the electrolytic capacitor Cs is charged with a voltage smoothed into the fixed voltage.

    [0027] In the present invention, although the resistor Rs is used for the energy-absorbing circuit 28, the resistor Rs may be omitted, if there is no need to minimize the rapid electrolytic capacitor Cs charging.

    [0028] A rectifying circuit 30 is connected to a point located closer to the alternating-current power supply than the relay S to apply a voltage to the electrolytic capacitor Cs via the rectifying circuit 30 in the present invention. That is, even when the relay S is Off, a voltage can be applied to the electrolytic capacitor Cs. The rectifying circuit 30 is a half-wave rectifying circuit consisting of one diode Dss. The anode of the diode Dss is connected to the alternating-current power supply. A direct current voltage is generated by half-wave rectification. This makes it possible to apply the direct current voltage to the electrolytic capacitor Cs.

    [0029] The control circuit 26 transmits a signal to turn the relay S on or transmits a control signal to drive a switching power element to the inverter 20. The control circuit 26 drives a charging voltage of the electrolytic capacitor Cs as a power supply. As mentioned above, it is possible to secure the power supply of the control circuit 26 because the electrolytic capacitor Cs is charged even though the relay S is Off. It is possible to transmit a signal to turn the relay S on and drive the power converter circuit 10 because the control circuit 26 is always driven. When the relay S is On, the electrolytic capacitor Cs is charged via the diode Ds and the resistor Rs. The voltage is converted into a voltage which is capable of driving the control circuit 26 by a DC/DC converter 32 when necessary.

    [0030] A resistor Rss is provided between the rectifying circuit 30 and the electrolytic capacitor Cs. This resistor Rss reduces electric current. When the resistor Rs of the energy-absorbing circuit 28 is too great, a drop in voltage in the resistor Rs at the time when energy is absorbed, in other words, when an electric current flows to the resistor Rs, resulting in a rise in voltage Vdc. Thus, there are more cases where the resistor Rss is set to be greater than the resistor Rs. In addition, the resistor Rss may be provided at a point located closer to the power supply 12 than the rectifying circuit 30 in the case where the resistor RSS is located in a pathway between the power supply 12 and the electrolytic capacitor Cs.

    [0031] When the value of the resistor Rss is the same as that of the resistor Rs, while the resistor Rss still remains like a power converter circuit 10b shown in FIG. 2, an output of the rectifying circuit 30 may be connected to a point between the diode Ds of the energy-absorbing circuit 28 and the resistor Rs. Further, like a power converter circuit 10c shown in FIG. 3, the output of the rectifying circuit 30 may be connected to a point between the diode Ds of the energy-absorbing circuit 28 and the resistor Rs. As a result, the resistor Rss is series-connected to the resistor Rs, so that two resistors Rss and Rs reduce the electric current. As mentioned above, the value of the resistor Rss is appropriately set.

    [0032] It is to be understood that the rectifying circuit 30 is not limited to a half-wave rectifying circuit. As indicated in a power converter circuit 10d shown in FIG. 4, a full-wave rectifying circuit consisting of four diodes DBss is connected to a point located closer to the alternating-current power supply than the relay S. An output of the full-wave rectifying circuit is applied to the electrolytic capacitor Cs. Use efficiency of a power supply voltage is more increased than the half-wave rectifying circuit. And as indicated in a power converter circuit 10e shown in FIG. 5, the output of the full-wave rectifying circuit may be connected to a point between the diode Ds of the energy-absorbing circuit 28 and the resistor Rs. In FIG. 5, there is a case in which it is impossible to set the resistor Rss like FIG. 2. The value of the resistor Rss is appropriately set.

    [0033] In the inverter 20, two switching power elements (transistors) are series-connected to each other and a connecting section thereof is connected to a terminal of the load 14. The series-connected switching power elements are connected to the first power supply line 22 and the second power supply line 24. Since the load 14 is a three-phase load, the total number of the switching power elements is six. A reflux diode is parallel connected to each switching power element. A desired three-phase electric current is outputted to the load 14 by the adjustment of the timing of switching on/off of the switching power elements using the control circuit 26.

    [0034] As described above, it is possible to apply a voltage to the electrolytic capacitor Cs in the DC section 18 located on the subsequent stage of the diode group 16 from the former stage, not from the relay S in the present invention. Even when the relay S is Off, it is possible to cause the control circuit 26 to drive using the electrolytic capacitor Cs as a power supply. As a result, there is no possibility that the relay S may remain Off like a conventional one. Further, it is possible to avoid overvoltage by the electrolytic capacitor Cs of the energy-absorbing circuit 28 as well as a conventional one.

    [0035] For instance, the embodiment is also applicable to a three-phase inverter without capacitor, although a single-phase inverter without capacitor shown in FIG. 1 is also applicable.

    DESCRIPTION OF THE REFERENCE NUMERALS



    [0036] 10, 10b, 10c, 10d, 10e: power converter circuit; 12: alternating-current power supply; 14: load; 16: diode group; 18: DC section; 20: inverter; 22: power supply line of upper arm; 24: power supply line of lower arm; 26: control circuit; 28: energy-absorbing circuit; 30: rectifying circuit; 32: DC/DC converter


    Claims

    1. A power converter circuit (10) comprising:

    a diode group (16) including a plurality of diodes arranged to rectify an output voltage of an alternating-current power supply (12);

    a relay (S) provided at a point located closer to the alternating-current power supply (12) than the diode group (16) ;

    a DC section (18) where an output voltage of the diode group (16) is applied; and

    an inverter (20) arranged to output a three-phase alternating-electric current to a three-phase load (14),

    the DC section (18) has a maximum pulse voltage twice as great as a minimum pulse voltage thereof,

    characterized in that

    the DC section (18) includes an energy-absorbing circuit (28) being a series circuit between a diode (Ds) and an electrolytic capacitor (Cs), and

    a rectifying circuit (30) is directly connected to a point located closer to the alternating-current power supply (12) than the relay (S) and is connected to the cathode of the diode (Ds) in the energy-absorbing circuit (28) to provide a pathway arranged to apply the output voltage of the alternating-current power supply (12) from the alternating-current power supply (12) to the electrolytic capacitor (Cs) via the rectifying circuit (30), not via the relay (S), when the relay is off.


     
    2. The power converter circuit (10) according to claim 1, further comprising a control circuit (26) arranged and configured to control the inverter (20) using a charging voltage of the electrolytic capacitor (Cs) as a power supply.
     
    3. The power converter circuit (10) according to claim 1 or claim 2, further comprising a control circuit (26) arranged and configured to switch the relay (S) on/off using the charging voltage of the electrolytic capacitor (Cs) as a power supply.
     
    4. The power converter circuit (10) according to any one of claims 1 to 3, wherein the energy-absorbing circuit (28) further comprises a resistor (Rs) and is a series circuit among the diode (Ds), a resistor (Rs), and the electrolytic capacitor (Cs); and
    the rectifying circuit (30) is connected to either point of connection between the diode (Ds) and resistor (Rs) or the resistor (Rs) and the electrolytic capacitor (Cs).
     
    5. The power converter circuit (10) according to any one of claims 1 to 4, wherein the pathway arranged to apply the output voltage of the alternating-current power supply (12) to the electrolytic capacitor (Cs) via the rectifying circuit (30) includes a resistor (Rss).
     
    6. The power converter circuit (10) according to any one of claims 1 to 5, wherein the rectifying circuit (30) is one of a full-wave rectifying circuit and a half-wave rectifying circuit.
     


    Ansprüche

    1. Stromwandlerschaltung (10), umfassend:

    eine Diodengruppe (16), einschließlich einer Vielzahl von Dioden, die zum Gleichrichten einer Ausgangsspannung einer Wechselstromversorgung (12) angeordnet ist;

    ein Relais (S), das an einem Punkt bereitgestellt ist, der sich näher an der Wechselstromversorgung (12) befindet als die Diodengruppe (16);

    einen Gleichstromabschnitt (18), an den eine Ausgangsspannung der Diodengruppe (16) angelegt ist; und

    einen Wechselrichter (20), der angeordnet ist, um einen dreiphasigen elektrischen Wechselstrom an eine dreiphasige Last (14) auszugeben,

    wobei der Gleichstromabschnitt (18) eine maximale Impulsspannung aufweist, die doppelt so groß ist wie eine minimale Impulsspannung davon,
    dadurch gekennzeichnet, dass

    der Gleichstromabschnitt (18) einen Energieabsorptionskreis (28) einschließt, der eine Reihenschaltung zwischen einer Diode (Ds) und einem Elektrolytkondensator (Cs) ist, und

    ein Gleichrichterkreis (30) direkt mit einem Punkt verbunden ist, der sich näher an der Wechselstromversorgung (12) als das Relais (S) befindet und mit der Kathode der Diode (Ds) in dem Energieabsorptionskreis (28) verbunden ist, um einen Pfad bereitzustellen, der angeordnet ist, um die Ausgangsspannung der Wechselstromversorgung (12) von der Wechselstromversorgung (12) über den Gleichrichterkreis (30) und nicht über das Relais (S) an den Elektrolytkondensator (Cs) anzulegen (S), wenn das Relais ausgeschaltet ist.


     
    2. Stromwandlerschaltung (10) nach Anspruch 1, ferner umfassend einen Steuerkreis (26), der angeordnet und konfiguriert ist, um den Wechselrichter (20) unter Verwendung einer Ladespannung des Elektrolytkondensators (Cs) als Stromversorgung zu steuern.
     
    3. Stromwandlerschaltung (10) nach Anspruch 1 oder Anspruch 2, ferner umfassend einen Steuerkreis (26), der angeordnet und konfiguriert ist, um das Relais (S) unter Verwendung der Ladespannung des Elektrolytkondensators (Cs) als Stromversorgung ein- und auszuschalten.
     
    4. Stromwandlerschaltung (10) nach einem der Ansprüche 1 bis 3, wobei der Energieabsorptionskreis (28) ferner einen Widerstand (Rs) umfasst und eine Reihenschaltung zwischen der Diode (Ds), einem Widerstand (Rs) und dem Elektrolytkondensator (Cs) ist; und
    der Gleichrichterkreis (30) entweder mit einem Verbindungspunkt zwischen der Diode (Ds) und dem Widerstand (Rs) oder dem Widerstand (Rs) und dem Elektrolytkondensator (Cs) verbunden ist.
     
    5. Stromwandlerschaltung (10) nach einem der Ansprüche 1 bis 4, wobei der Pfad, der angeordnet ist, um die Ausgangsspannung der Wechselstromversorgung (12) über den Gleichrichterkreis (30) an den Elektrolytkondensator (Cs) anzulegen, einen Widerstand (Rss) einschließt.
     
    6. Stromwandlerschaltung (10) nach einem der Ansprüche 1 bis 5, wobei der Gleichrichterkreis (30) eines von einem Vollwellengleichrichtkreis und einem Halbwellengleichrichtkreis ist.
     


    Revendications

    1. Circuit convertisseur de puissance (10) comprenant :

    un groupe de diodes (16) incluant une pluralité de diodes conçues pour redresser une tension de sortie d'une source d'alimentation en courant alternatif (12) ;

    un relais (S) prévu à un point situé plus près de la source d'alimentation en courant alternatif (12) que le groupe de diodes (16) ;

    une section CC (18) où une tension de sortie du groupe de diodes (16) est appliquée ; et

    un onduleur (20) conçu pour produire en sortie un courant électrique alternatif triphasé vers une charge triphasée (14),

    la section CC (18) a une tension d'impulsion maximale deux fois supérieure à une tension d'impulsion minimale de celle-ci,

    caractérisé en ce que

    la section CC (18) inclut un circuit d'absorption d'énergie (28) étant un circuit en série entre une diode (Ds) et un condensateur électrolytique (Cs), et

    un circuit redresseur (30) est connecté directement à un point situé plus près de la source d'alimentation en courant alternatif (12) que le relais (S) et est connecté à la cathode de la diode (Ds) du circuit d'absorption d'énergie (28) pour fournir un trajet conçu pour appliquer la tension de sortie de la source d'alimentation en courant alternatif (12) de la source d'alimentation en courant alternatif (12) au condensateur électrolytique (Cs) via le circuit redresseur (30), et non via le relais (S), lorsque le relais est hors tension.


     
    2. Circuit convertisseur de puissance (10) selon la revendication 1, comprenant en outre un circuit de commande (26) conçu et configuré pour commander l'onduleur (20) en utilisant une tension de charge du condensateur électrolytique (Cs) en tant que source d'alimentation.
     
    3. Circuit convertisseur de puissance (10) selon la revendication 1 ou la revendication 2, comprenant en outre un circuit de commande (26) conçu et configuré pour mettre le relais (S) sous tension/hors tension en utilisant la tension de charge du condensateur électrolytique (Cs) en tant que source d'alimentation.
     
    4. Circuit convertisseur de puissance (10) selon l'une quelconque des revendications 1 à 3, dans lequel le circuit d'absorption d'énergie (28) comprend en outre une résistance (Rs) et est un circuit en série entre la diode (Ds), une résistance (Rs) et le condensateur électrolytique (Cs) ; et
    le circuit redresseur (30) est connecté à l'un ou l'autre point de connexion entre la diode (Ds) et la résistance (Rs) ou la résistance (Rs) et le condensateur électrolytique (Cs).
     
    5. Circuit convertisseur de puissance (10) selon l'une quelconque des revendications 1 à 4, dans lequel le trajet conçu pour appliquer la tension de sortie de la source d'alimentation en courant alternatif (12) au condensateur électrolytique (Cs) via le circuit redresseur (30) inclut une résistance (Rss).
     
    6. Circuit convertisseur de puissance (10) selon l'une quelconque des revendications 1 à 5, dans lequel le circuit redresseur (30) est l'un d'un circuit redresseur à deux alternances et d'un circuit redresseur à une alternance.
     




    Drawing

















    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description




    Non-patent literature cited in the description