Abstract:
A thrust reverser device for an aircraft includes at least two thrust reversers, and each of them includes a movable cowl movably actuated by an actuator driven by an electric motor. The electric motor is powered by a single power-conversion module including at least one autotransformer which is supplied with an alternating electric voltage and connected to at least one rectifier stage converting the alternating electric voltage into a direct voltage. The rectifier stage is connected to a current balancing stage and a current smoothing stage, supplying with the direct voltage the electric motor of the electric actuator of the movable cowl.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/FR2013/051507, filed on Jun. 27, 2013, which claims the benefit of FR 12/56155, filed on Jun. 28, 2012. The disclosures of the above applications are incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to a thrust reverser device for an aircraft comprising at least two thrust reversers. 
     BACKGROUND 
     The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
     An aircraft is propelled by a plurality of turbojet engines each housed in a nacelle that also accommodates a set of complementary devices related to its operation such as a thrust reverser device. 
     The role of a thrust reverser during landing of an aircraft is to improve its braking ability by redirecting forward at least a part of the thrust generated by the turbojet engine. 
     In this phase, the thrust reverser obstructs the gas ejection nozzle and directs the ejection flow of the engine to the front of the nacelle thereby generating a counter-thrust which adds to the braking of the wheels of the aircraft. 
     The means implemented to achieve this flow reorientation vary depending on the thrust reverser type. Regardless of the type of reverser, the structure of a thrust reverser comprises movable cowls displaceable between an opening position in which they open a passage within the nacelle intended for the diverted flow and a closing position in which they close this passage. 
     These movable cowls may fulfill by themselves the function of deflection or simply a function of actuation of other diverting means such as flaps of obstruction of the flow path. 
     The actuation of the thrust reverser, thus the displacement the movable cowl, is controlled according to prior art by hydraulic or pneumatic cylinders which require a network of transportation of pressurized fluid. 
     This pressurized fluid is conventionally obtained either by air tapping on the turbojet engine in the case of a pneumatic system or by picking upon the hydraulic circuit of the aircraft in the case of a hydraulic system. 
     The necessity for complex equipment for allowing air or fluid picking up, and the network of hydraulic or pneumatic transportation, significantly make the aircraft heavier. 
     Moreover, such systems require a significant maintenance because the slightest leakage in the hydraulic or pneumatic network may have harmful consequences on the thrust reverser as well as on other parts of the nacelle. 
     To overcome these drawbacks, the thrust reverser manufacturers have sought to replace them with electric actuation systems. 
     Each thrust reverser is supplied with electrical energy by a power source of the aircraft. Each of the power sources is connected to a power-conversion module providing the conversion from the alternating voltage delivered by the power source into a direct voltage. 
     A first drawback of this type of architecture is related to the number of power lines necessary for the operation of the actuation systems of the thrust reversers, the aircraft generally offering only a limited number of power lines. 
     A second drawback comes from the fact that the actuation systems of the thrust reversers are segregated. Indeed, when the various thrust reversers do not deploy simultaneously or when only one thrust reverser is deployed, it is up to the pilot to check that the non-deployed thrust reverser has a minimum thrust on the corresponding turbojet engine. 
     The patent application EP 2 236 413 known from the prior art refers to an aircraft source supplying a power-conversion module that distributes the power supply to a plurality of actuators. 
     However, such an electrical architecture is adapted for actuators that can be sequentially supplied but is not conformed for a use specific to the actuators of thrust reversers to be supplied at the same time with minimum power dissymmetry between each actuator. 
     SUMMARY 
     The present disclosure provides a thrust reverser device for an aircraft comprising at least two thrust reversers, each of said thrust reversers comprising at least one cowl movably mounted between a closing position and an opening position, said cowl being actuated by at least one actuator able to be driven by at least one electric motor, said electric motors being electrically supplied by a single power-conversion module electrically supplied by a single power source of said aircraft, said device being remarkable in that the power-conversion module comprises at least one autotransformer supplied with an alternating electric voltage by the power source of said aircraft and connected to at least one rectifier stage adapted for converting said alternating voltage into direct voltage, said rectifier stage being connected to a current balancing stage and/or to a current smoothing stage, adapted for supplying with direct voltage said electric motor of said actuator of said cowl of the thrust reverser. 
     Thus, by providing a single power-conversion module adapted for electrically supplying the actuators of each thrust reverser, the power supply of said module is carried out by a single power source of the network of the aircraft, which allows limiting the number of power sources necessary to the power supply of the actuators while limiting the current harmonics on this power source of the aircraft network. 
     Moreover, by gathering in a single module all the components necessary to supply all the actuators of the thrust reversers, the thrust reverser device is simplified. 
     According to a first form, the power-conversion module comprises two autotransformers, each being supplied with alternating electric voltage by said power source of said aircraft, each of said autotransformers comprising phase-shifted outputs and connected to at least two rectifier circuits, each of said rectifier circuits of a same autotransformer being connected to a single interphase inductor at least adapted for balancing the currents and delivering a direct voltage supplying at least one electric motor of an actuator of the cowl of a thrust reverser. 
     According to a second form, the power-conversion module comprises two autotransformers supplied with an alternating electric voltage by said power source of said aircraft, and each of said autotransformers comprising phase-shifted outputs and connected to at least one rectifier circuit, each of said rectifier circuits of a same autotransformer being connected to a coupled DC inductor at least adapted for smoothing the current and delivering a direct voltage supplying at least one electric motor of an actuator of the cowl of a thrust reverser. 
     Thus, according to this form of the present disclosure, the power-conversion module comprises a total of two rectifier circuits, thereby significantly reducing the weight of the set relative to the first form. 
     In a third form, the power-conversion module comprises a single autotransformer supplied with alternating electric voltage by said power source of said aircraft, said autotransformer comprising two phase-shifted outputs connected to at least two rectifier circuits, each of said rectifier circuits being connected to a coupled DC inductor at least adapted for smoothing the current and delivering a direct voltage supplying at least one electric motor of an actuator of the cowl of a thrust reverser. 
     Thanks to this third form, the weight of the power-conversion module is substantially reduced in that it comprises a single autotransformer. 
     According to one form, at least one rectifier circuit of the power-conversion module comprises a diode bridge comprising at least six diodes. 
     According to another form of the present disclosure, the power-conversion module further comprises at least one supervisor adapted for monitoring and controlling the actuators of the cowls of said thrust reversers, said supervisor being supplied with direct voltage by said inductors. 
     Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which: 
         FIG. 1  schematically illustrates the thrust reverser device of an aircraft according to the present disclosure, comprising two thrust reversers supplied by the power-conversion module according to a first form; 
         FIG. 2  illustrates the thrust reverser device according to the present disclosure, the power-conversion module being shown according to a second form; and 
         FIG. 3  illustrates the thrust reverser device according to the present disclosure, the power-conversion module being shown according to a third form. 
     
    
    
     The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
     DETAILED DESCRIPTION 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
     Referring to  FIG. 1 , illustrating the power management assembly  1  of the thrust reversers of an aircraft, the power-conversion module being shown according to a first form. 
     Such a power management assembly comprises a power-conversion module  100  supplied at the input by a power source  3  of the aircraft, and connected at the output to two actuators  5  and  5 ′, each being adapted for actuating the cowl of thrust reverser alternately between an opening position and a closing position. Typically, an actuator comprises a power electronic board, for example an inverter, allowing management of the electric motor  6 ,  6 ′ of each actuator. 
     The power source  3  delivers three-phase alternating voltage Va, Vb, Vc to the input conductors  7   a ,  7   b  and  7   c  that should be converted into direct voltage. 
     The power-conversion module  100  comprises two autotransformers  101  and  101 ′, each being connected to the three input conductors  7   a  to  7   c  of the power source  3  of the aircraft. 
     Typically, the autotransformer  101  and  101 ′ each comprise a primary coil and two secondary coils (not shown) phase-shifted in order to reduce the current harmonics on the single power source of the aircraft network. 
     The primary coil comprises three primary windings, on the one hand connected together, and on the other hand connected to the input conductors  7   a ,  7   b  and  7   c.    
     The secondary coil comprises in turn six secondary windings connected to six output conductors  103   a  to  103   f , the conductors  103   a ,  103   b ,  103   c  being connected to a rectifier bridge  105 , and the conductors  103   d ,  103   e ,  103   f  being connected to a rectifier bridge  107 . 
     The configurations of the primary and secondary coils may vary according to the needs of the present disclosure. For example, the primary and secondary coils may equally have a star, triangle or mixed configuration, and the secondary coils may be phase-shifted. 
     The rectifier bridge  105  comprises six diodes  109   a  to  109   f , and delivers a direct voltage between the outputs  111  and  113 . The rectifier bridge  107  also comprises six diodes  115   a  to  115   f  and delivers a direct voltage between the outputs  117  and  119 . 
     The outputs  111 ,  113 ,  117 ,  119  are connected to an interphase inductor  121  in order to allow the balancing of the rectifier bridges. 
     The interphase inductor delivers a direct voltage between the outputs  123  and  125 . 
     Similarly to what has been described for the autotransformer  101 , the autotransformer  101 ′ is also connected to two rectifier bridges  105 ′ and  107 ′ of same configuration as the rectifier bridges  105  and  107 . The rectifier bridges  105 ′ and  107 ′ deliver two direct voltages respectively between the outputs  111 ′ and  113 ′, and  117 ′ and  119 ′, connected to an interphase inductor  121 ′. The interphase inductor  121 ′ delivers a direct voltage between the outputs  123 ′ and  125 ′. 
     The interphase inductors  121  and  121 ′ supply respectively the actuators  5  and  5 ′ of each thrust reverser with direct voltage. 
     As shown, the direct voltage delivered by the interphase inductor  121  supplies a DC/DC converter  127  which allows reducing the voltage at the output of the inductor in order to supply a single supervisor  129 . 
     For example, the interphase inductor delivers an output voltage of −135 volts/+135 V. The DC/DC converter allows reducing the output voltage to a voltage in the range of 28 volts. 
     The supervisor  129  allows monitoring and controlling of the actuators of the thrust reversers and the AC/DC converter. 
     The two output direct voltages  123 ,  125  and  123 ′,  125 ′ of the power converter  100  supply each actuator  5  and  5 ′ thanks to two contactors or “SSPC”  131 ,  133 , and  131 ′,  133 ′ controlled by a control member of the aircraft. 
     These contactors allow having a line of defense of power and are controlled by the aircraft. 
     More specifically, the supervisor receives control orders from the control unit of the electric motor of the actuator and manages the tracking of the trajectory during the opening and the closing of the cowls of the thrust reversers. 
     The supervisor also sends back to the control unit of the turbojet engine the state of the set comprising the power-conversion module  100 , the actuators  5  and  5 ′ of the thrust reverser cowls, and the contactors  131 ,  133 ,  131 ′,  133 ′. 
     The supervisor  129  transmits the control orders to the actuators  5  and  5 ′ via a field bus  135 ,  135 ′. 
     Referring now to  FIG. 2 , illustrating the power management assembly  1 , the power-conversion module being shown according to a second form. 
     The power management assembly  1  comprises a power-conversion module  200  comprising two autotransformers  201  and  201 ′. 
     The power-conversion module  200  is supplied at the input by the power source  3  of the aircraft and connected at the output to the actuators  5  and  5 ′ of the thrust reversers equipping each nacelle of the turbojet engine of the aircraft. 
     The power source  3  delivers a three-phase alternating electric voltage Va, Vb, Vc, respectively on the input conductors  7   a ,  7   b  and  7   c  that should be converted into direct voltage. 
     The autotransformers  201  and  201 ′ comprise each a primary coil and a secondary coil (not represented). 
     The primary coil comprises three primary windings, on the one hand connected together, and on the other hand connected to the input conductors  7   a ,  7   b  and  7   c.    
     Each primary winding respectively receives an alternating voltage V 2   a , V 2   b  and V 2   c . The secondary coil comprises in turn three secondary windings connected to three output conductors  203   a  to  203   c  connected to a rectifier bridge  205 . 
     The configurations of the primary and secondary coils may vary according to the needs of the present disclosure. For example, the primary and secondary coils may have a star, triangle or mixed configuration, and the secondary coils may be phase-shifted. 
     The rectifier bridge  205  comprises six diodes  209   a  to  209   f , and delivers a direct voltage between the outputs  211  and  213 . 
     The outputs  211  and  213  are connected to a coupled DC inductor  221  allowing the smoothing of the current of the rectifier bridge. 
     The coupled DC inductor  221  delivers a direct voltage between the outputs  223  and  225 . 
     Similarly to what has been described for the autotransformer  201 , the autotransformer  201 ′ comprises three primary windings each receiving an alternating voltage V′ 2   a , V′ 2   b  and V′ 2   c.    
     The secondary coil comprises three secondary windings connected to the three output conductors  203 ′ a  to  203 ′ c  connected to a rectifier bridge  205 ′ of same configuration as the rectifier bridge  205  and delivering a direct voltage between the outputs  211 ′ and  213 ′. 
     The outputs  211 ′ and  213 ′ are connected to a coupled DC inductor  221 ′ allowing the smoothing of the current of the rectifier bridge. 
     The coupled DC inductor delivers a direct voltage between the outputs  223 ′ and  225 ′. 
     The coupled DC inductors  221  and  221 ′ supply respectively the actuators  5  and  5 ′ of each thrust reverser with direct voltage. 
     The outputs  203   a  to  203   c  are phase-shifted relative to the outputs  203 ′ a  to  203 ′ c  and adapted for limiting the current harmonics on the power source of the network of the aircraft. 
     As shown, the DC direct voltage delivered by the coupled DC inductor  221  supplies a DC/DC converter  227  which reduces allows reducing the voltage at the output of the inductor in order to supply a single supervisor  229 , the operation of which is similar to that described for the first form. For example, the coupled DC inductor delivers an output voltage of −135 volts/+135 V. The DC/DC converter reduces allows reducing the output voltage to a voltage in the range of 28 volts. 
     The supervisor  229  allows monitoring and controlling the actuators of the thrust reversers and the AC/DC converter. 
     The two direct voltages of the outputs  223 ,  225  and  223 ′,  225 ′ of the power converter  200  supply each actuator  5  and  5 ′ thanks to two contactors or “SSPC”  231 ,  233 ,  231 ′,  233 ′. 
     These contactors allow having a line of defense of power and are controlled by the aircraft. 
     As described above, the supervisor receives control orders from the control unit of the electric motor of the actuator and manages the tracking of the trajectory during the opening and the closing of the cowls of the thrust reversers. 
     The supervisor also sends back to the control unit of the turbojet engine the state of the set comprising the power-conversion module  200 , the actuators  5  and  5 ′ of the thrust reverser cowls, and the contactors  231 ,  233 ,  231 ′,  233 ′. 
     The supervisor  229  transmits the control orders to the actuators  5  and  5 ′ via a field bus  235 ,  235 ′. 
     Referring now to  FIG. 3 , illustrating the power management assembly  1 , the power-conversion module being shown according to a third form, according to which the power-conversion module  300  comprises a single autotransformer  301 , of power equal to twice the power of the autotransformers  101 ,  101 ′,  201  and  201 ′. 
     The power-conversion module  300  is supplied at the input by the power source  3  of the aircraft and connected at the output to the actuators  5  and  5 ′ of the thrust reversers equipping each nacelle of turbojet engine of the aircraft. 
     The power source  3  delivers three-phase alternating voltage Va, Vb, Vc on the input conductors  7   a ,  7   b  and  7   c  that should be converted into direct voltage. 
     The autotransformer  301  comprises a primary coil and two secondary phase-shifted coils and adapted for reducing the current harmonics on the single power source of the aircraft network (not shown). The primary coil comprises three primary windings, on the one hand connected together, and on the other hand connected to the input conductors  7   a ,  7   b  and  7   c.    
     The secondary coil comprises six secondary windings connected to six output conductors  303   a  to  303   f.    
     The configurations of the primary and secondary coils may vary according to the needs of the present disclosure. For example, the primary and secondary coils may have a star, triangle or mixed configuration, and the secondary coils may be phase-shifted. 
     The output conductors  303   a ,  303   b ,  303   c  are connected to a rectifier bridge  305 , and the output conductors  303   d ,  303   e ,  303   f  are connected to a rectifier bridge  305 ′. 
     The rectifier bridges  305  and  305 ′ each comprise respectively 6 diodes  307   a  to  307   f  and  307 ′ a  to  307 ′ f , and each delivering a direct voltage between the outputs  311  and  313 , and  311 ′ and  313 ′. 
     The outputs  311  and  313  are connected to a coupled DC inductor  321  and the outputs  311 ′,  313 ′ are connected to a coupled inductor  321 ′, the inductors  321  and  321 ′ allow balancing and smoothing the currents of the rectifier bridges  305  and  305 ′. 
     The coupled DC inductors  321  and  321 ′ each deliver a direct voltage between the outputs  323 ,  325  and  323 ′,  325 ′, respectively supplying the actuators  5  and  5 ′ of each thrust reverser with direct voltage. 
     As shown, the DC direct voltage delivered by the coupled DC inductor  321  supplies a DC/DC converter  327  which reduces allows reducing the voltage at the output of the inductor in order to supply a single supervisor  329 , the operation of which is similar to that described for the first and second forms. The supervisor  329  allows monitoring and controlling of the actuators of the thrust reversers and the AC/DC converter. For example, the coupled inductor delivers an output voltage of −135 volts/+135 V. The DC/DC converter reduces allows reducing the output voltage to a voltage in the range of 28 volts. 
     The two direct voltages of the outputs  323 ,  325  and  323 ′,  325 ′ of the power converter  300  supply each actuator  5  and  5 ′ via two contactors or “SSPC”  331 ,  333 ,  331 ′,  333 ′. 
     These contactors allow having a line of defense of power and are controlled by the aircraft. 
     As described above, the supervisor receives control orders from the control unit of the electric motor of the actuator and manages the tracking of the trajectory during the opening and the closing of the cowls of the thrust reversers. 
     The supervisor also sends back to the control unit of the turbojet engine the state of the set comprising the power-conversion module  300 , the actuators  5  and  5 ′ of the thrust reverser cowls, and the contactors  331 ,  333 ,  331 ′,  333 ′. 
     The supervisor  229  transmits the control orders to the actuators  5  and  5 ′ via a field bus  335 ,  335 ′. 
     Thanks to the present disclosure, all of the components necessary to the power conversion are gathered in a single casing. Therefore, a single power source of the aircraft network is necessary for supplying the actuators of the thrust reversers of the aircraft, thereby greatly simplifying the electrical architectures of actuation of the thrust reversers. 
     The power-conversion modules  200  and  300  of the second and the third forms allow dividing the number of diode bridges by two relative to the first form, thereby reducing the weight of the assembly. Furthermore, the power-conversion module according to the third form presents a reduced weight in that the power-conversion module comprises a single autotransformer. 
     In addition, the architecture of this present disclosure also allows attenuating the harmonic distortions on the network. 
     The power-conversion module is positioned within the aircraft fuselage, a particularly advantageous disposition for small aircrafts, when the turbojet engines are integral to the fuselage. 
     The power management assembly has been described with reference to the power supply of two actuators of thrust reversers. It is however quite possible to adapt the power-conversion module for a higher number of thrust reversers actuators. 
     In addition, all the description has been made with reference to a power-conversion module comprising a system called “12-pulse” system, that is to say, the power-conversion module comprises 12 diodes per autotransformer. However, the power-conversion module may equally comprise a 18-pulse, 24-pulse system, etc. if the person skilled in the art finds in it a particular benefit.