Chain of electrical modules for powering a rotating electrical machine

Abstract

Chain (30) of modules (10) for an electrical circuit (100) comprising a first terminal (11a) and a second terminal (11b), each module (10) comprising: - a primary terminal (11a) and a secondary terminal (11b), the primary terminal (11a) being connected to the secondary terminal (11b) of another module (10) and / or the secondary terminal (11b) is connected to the primary terminal (11a) of another module (10), - an electrical energy storage unit (10), - an H-shaped switching bridge (13), the bridge (13) comprising two switching arms comprising two controllable switches (14a, 14b, 14c, 14d) arranged on either side of a midpoint (13a, 13b), each midpoint (13a, 13b) being connected to one of the terminals (11a, 11b) of the module (10), the electrical energy storage unit (12) being arranged in a branch in parallel with the switching arms, and - at least one module (10) comprising a DC / DC converter (15), comprising controllable switches,connected on the one hand to the terminals of the electrical energy storage unit (12) and on the other hand to a tertiary terminal (16a) and to a quaternary terminal (16b) of the module (10), Characterized in that at least one DC / DC converter (15) is an isolated and reversible converter. Abstract figure: [Fig. 1],

Description

Title of the invention: Chain of electrical modules for supplying a rotating electrical machine

[0001] The present application refers to a chain of modules for a power supply circuit of a rotating electrical machine for propelling a vehicle.

[0002] In a known example, in particular from application US11799392B2, such a chain of modules comprises a first terminal and a second terminal, each module comprising:

[0003] - a primary terminal and a secondary terminal, the primary terminal being connected to the secondary terminal of another module and / or the secondary terminal is connected to the primary terminal of another module

[0004] - an electrical energy storage unit,

[0005] - an H-shaped switching bridge, the bridge comprising two switching arms comprising two controllable switches arranged on either side of a midpoint, each midpoint being connected to one of the terminals of the module, the electrical energy storage unit being arranged in a branch in parallel with the switching arms, and

[0006] - at least one module comprising a DC / DC converter, comprising inter controllable breakers, connected on the one hand to the terminals of the electrical energy storage unit and on the other hand to a tertiary terminal and a quaternary terminal of the module.

[0007] It may be desirable to intelligently control the switches within the modules to ensure that the discharge of the energy storage units is equitable between the different modules. There is a need to simplify the load balancing of the energy storage units within the modules.

[0008] There is also a need to propose a solution for powering consumers within the vehicle requiring a greater quantity of energy, for example the air conditioning or cooling systems of the vehicle's powertrain. These consumers cannot be connected to the DC / DC converters of the modules because the nominal voltages of the electrical energy storage units within the modules are generally of the order of a few volts or a few tens of volts, for example between 3V and 60V, whereas these consumers may have a nominal voltage of several hundred volts, for example 400V, 800V or even more than 1000V, the voltage conversion between these two orders of magnitude of nominal voltage requiring an infrastructure that is too expensive and / or too energy-consuming for this circuit topology.

[0009] The invention aims to meet all or part of these needs and it achieves this by one of its aspects, by means of a chain of modules for an electrical circuit comprising a first terminal and a second terminal, each module comprising

[0010] - a primary terminal and a secondary terminal, the primary terminal being connected to the secondary terminal of another module and / or the secondary terminal is connected to the primary terminal of another module,

[0011] - an electrical energy storage unit,

[0012] - an H-shaped switching bridge, the bridge comprising two switching arms comprising two controllable switches arranged on either side of a midpoint, each midpoint being connected to one of the terminals of the module, the electrical energy storage unit being arranged in a branch in parallel with the switching arms, and

[0013] - at least one module comprising a DC / DC converter, comprising inter controllable breakers, connected on the one hand to the terminals of the electrical energy storage unit and on the other hand to a tertiary terminal and to a quaternary terminal of the module,

[0014] characterized in that the DC / DC converter is an isolated converter and is reversible.

[0015] This isolated and reversible DC / DC converter allows, when several modules are connected to each other directly by their tertiary and quaternary terminals or through a continuous power supply bus, to be able to carry out an energy transfer between these two modules. More precisely, at least one module is capable of transferring energy to another module, the DC / DC converters of these modules discharging and charging their electrical energy storage unit respectively.

[0016] According to the invention, the modules are arranged within the chain in such a way that their primary terminal is connected to the secondary terminal of another module and their secondary terminal is connected to the primary terminal of another module, with the exception of a module whose primary terminal is connected to the first terminal of the chain and a module whose secondary terminal is connected to the second terminal of the chain.

[0017] All modules in the chain may include a DC / DC converter, this converter being an isolated and reversible converter.

[0018] The first and second terminals of the chain may define the only output voltage of the chain other than voltages defined between tertiary and quaternary terminals of one of the modules.

[0019] This means that there is no intermediate output terminal within the chain, i.e. an output terminal connected both to the primary terminal of a first module and to the secondary terminal of another module in the chain, this primary terminal and this secondary terminal being connected together.

[0020] The electrical energy storage unit may have a nominal voltage of between 3 and 60V. For example, the nominal voltage of the energy storage unit electric can be 5, 12, 24 or 48V.

[0021] The electrical energy storage unit may be a cell of a lithium-ion type cell battery.

[0022] The modules may comprise a bidirectional switching cell arranged between their primary terminal and their secondary terminal, this switching cell comprising at least one controllable semiconductor switch.

[0023] The presence of this switching cell between the terminals of the modules makes it possible to achieve redundancy when it is desired to disconnect the energy storage unit of one of the modules from the rest of the chain. Thus, if the switching cell of said module is defective, it is possible to disconnect the energy storage unit from this module by controlling the switches of the switching bridge, and if one or more switches of the switching bridge are defective, it is possible to functionally disconnect the energy storage unit from the rest of the chain by controlling the switching cell between the terminals of the module. This redundancy can make a circuit using a chain of modules such as described more resistant to malfunctions, extend its service life, and meet a safety requirement for the user of the vehicle.

[0024] The switching cell between the primary terminal and the secondary terminal of the modules may comprise a bidirectional transistor, in particular a four-quadrant GaN-based power transistor.

[0025] Alternatively, the switching cell between the primary terminal and the secondary terminal of the modules may comprise two unidirectional transistors mounted in antiparallel, in particular MOS field effect transistors or bipolar transistors.

[0026] Alternatively, the switching cell between the primary terminal and the secondary terminal of the modules may comprise a microelectromechanical system switch.

[0027] The switching cell between the primary terminal and the secondary terminal is different from a mechanical relay.

[0028] The switches of the switching bridge within the module and the switching cell may be of the same type.

[0029] The energy storage unit within the modules can be arranged in a branch that is devoid of switches. In other words, the electrical energy storage unit is mounted between two nodes of the electrical circuit of the module and is not in series between these two nodes with any switch.

[0030] The invention also relates, according to one of its aspects, to an electrical circuit for supplying a rotating electrical machine for propelling a vehicle comprising:

[0031] - a polyphase electric machine,

[0032] - an input interface capable of being connected to a charging station,

[0033] - a power supply bus, intended to be connected to an electrical consumer,

[0034] - a plurality of electrical module strings, each string being as described previously,

[0035] - a system of switches allowing each chain to be connected to the terminals of a phase of the electrical machine or at the input interface, and

[0036] - a control unit, capable of controlling the switches within the electrical circuit,

[0037] The tertiary and quaternary terminals of all or part of the modules of the chains being connected to the power bus.

[0038] The control unit can control the switches of the DC / DC converters such that at least one module transfers energy to at least one other module via the power bus, the DC / DC converters of these modules discharging and charging their energy storage unit respectively.

[0039] This energy transfer is advantageous because it can be carried out between modules arranged on the same chain and / or different chains thanks to their connection to the power supply bus.

[0040] The circuit may comprise a second power supply bus, intended to be connected to an electrical consumer with a nominal voltage higher than the nominal voltage of the consumer intended to be connected to the first power supply bus and an additional chain of modules, all the modules of the additional chain comprising a DC / DC converter, this converter being an isolated and reversible converter connected by its terminals to the second power supply bus, the tertiary and quaternary terminals of the modules of the additional chain being connected to the first power supply bus.

[0041] The control unit can control the switches of the DC / DC converters so that the modules of the plurality of strings transfer energy to the modules of the additional string through the power bus, the DC / DC converters of the modules of the plurality of strings and the DC / DC converters of the modules of the additional string discharging and charging their energy storage unit respectively, when a charging station applies a voltage to the input interface.

[0042] This transfer of energy from the modules of the plurality of strings to the additional string makes it possible to charge the electrical energy storage units of the modules of the additional string when a charging station applies a voltage to the input interface of the circuit, even if the additional string is not directly connected to the terminals of the input interface.

[0043] The control unit can control the switches of the DC / DC converters so that the modules of the plurality of strings transfer energy to the modules of the additional string via the power bus, the DC / DC converters of the modules of the plurality of strings and the DC / DC converters of the modules of the additional chain discharging and charging their energy storage unit respectively, when the electric machine operates as a generator.

[0044] This transfer of energy from the modules of the plurality of strings to the additional string makes it possible to charge the electrical energy storage units of the modules of the additional string when the electrical machine operates as a generator, even if the additional string is not directly connected to the phases of the electrical machine.

[0045] The control unit can control the switches of the DC / DC converters so that the modules of the additional string transfer energy to the modules of the plurality of strings via the power bus, the DC / DC converters of the modules of the plurality of strings and the DC / DC converters of the modules of the additional string charging and discharging their energy storage unit respectively, when the load connected to the second power bus is less than a predetermined threshold or zero.

[0046] The threshold value may correspond to a ratio between the energy consumed by the consumers intended to be connected to the second power supply bus and the maximum energy that the additional chain can provide, in particular the threshold value may be equal to 10%.

[0047] This transfer of energy from the modules of the additional chain to the plurality of chains makes it possible to charge the electrical energy storage units of the plurality of chains when the consumers connected to the second power bus consume little energy or are not activated, and consequently can extend the autonomy of the circuit.

[0048] The supply of the additional power supply bus from the input interface or from the stator phases of the rotating electrical machine may be carried out exclusively by transfer of electrical energy via the first power supply bus.

[0049] The electrical energy storage units contained in the modules of the additional string may have a different chemical composition, size and / or voltage rating than the electrical energy storage units contained in the modules of the plurality of strings.

[0050] The number of chains implemented in the plurality of chains may be greater than or equal to the number of phases of the rotating electrical machine.

[0051] The switch system can allow each string of the plurality of strings to be connected to the terminals of a phase of the electrical machine to which this string is dedicated. In other words, a given string can only be connected to a single phase of the stator of the electrical machine.

[0052] The rotating electrical machine is for example a synchronous machine, for example a three-phase synchronous machine or a synchronous machine whose The stator electrical winding defines a dual three-phase system. The stator electrical winding is formed, for example, by wires or by conductive bars connected to each other.

[0053] In all of the above, the rotor may be a claw rotor. This rotor then comprises a first and a second nested pole wheels, the first pole wheel defining a series of claws of generally trapezoidal shape, each claw extending axially towards the second pole wheel, the second pole wheel defining a series of claws of generally trapezoidal shape, each claw extending axially towards the first pole wheel. A permanent magnet may be received between two consecutive claws circumferentially speaking for the rotor.

[0054] Alternatively, the rotor may be other than a claw rotor, for example comprising a stack of laminations or being a cage rotor.

[0055] When the rotating machine is a synchronous machine, it may have a wound rotor or a permanent magnet rotor.

[0056] The rotating electrical machine may have a rated electrical power of 25kW, 100kW, 200kW, or more.

[0057] The circuit control unit may be single or comprise a main control unit and several subsidiary control units, for example one subsidiary control unit per chain in the circuit and / or one subsidiary control unit per module.

[0058] The electrical circuit may be reversible, i.e. the switches within the circuit may be controlled so that the strings of modules supply an alternating voltage across the input interface.

[0059] The invention may be better understood by reading the following description of non-limiting examples of its implementation:

[0060] [Fig.l] represents a module intended to be implemented within a chain of electrical modules of a circuit for the power supply of a rotating electrical machine.

[0061] [Fig.2a] represents a chain of modules according to [Fig.l],

[0062] [Fig.2b] represents an example of output voltage of a string of modules according to [Fig.2a] for the power supply of an electric machine.

[0063] [Fig.2c] represents an example of input voltage of a string of modules according to [Fig.2a] allowing the electrical energy storage units to be charged within the modules.

[0064] [Fig. 3] represents a circuit for the power supply of an electrical machine rotating propulsion system of a vehicle, employing a plurality of module chains according to [Fig.2a], and an additional chain according to [Fig.2a] for supplying electrical consumers.

[0065] [Fig.l] shows a module 10 intended to be implemented within a chain of electrical modules of a circuit for supplying a rotating electrical machine.

[0066] The module 10 as shown in [Fig.l] comprises a primary terminal 11a and a secondary terminal 11b, the voltage between terminals 11a and 11b being denoted Vm.

[0067] The module 10 also comprises an electrical energy storage unit 12, of nominal voltage Vc. This electrical energy storage unit may be a cell of a battery employing a plurality of cells, and may have a nominal voltage of between 3 and 60V for example. This energy storage unit 22 is arranged in a branch in parallel with a switching bridge 13, this branch not comprising switches. This switching bridge 13 is mounted in an H shape and comprises controllable switches 14a, 14b, 14c, 14d, arranged on either side of the midpoints 13a and 13b, these midpoints being connected respectively to the primary terminal 11a and the secondary terminal 11b of the module 10. In the example shown in [Fig.l], the switches 14a, 14b, 14c, 14d are MOS field effect transistors.

[0068] When a control unit controls the switches of the switching bridge 13 such that the switches 14a, 14d are in the open position and the switches 14b, 14c are in the closed position, the voltage Vm between the terminals 11a and 11b of the module 10 is equal to Vc. When the switches 14b, 14c are in the open position and the switches 14a, 14d are in the closed position, the voltage Vm between the terminals 11a and 11b of the module 10 is equal to -Vc.

[0069] When a control unit controls the switches of the switching bridge 13 such that the switches 14a, 14d are in the closed position and the switches 14b, 14c are in the open position, the voltage Vm between the terminals 11a and 11b of the module 10 is equal to Vc. When the switches 14b, 14c are in the closed position and the switches 14a, 14d are in the open position, the voltage Vm between the terminals 11a and 11b of the module 10 is equal to -Vc.

[0070] The module 10 also comprises a DC / DC converter 15, on the one hand connected to the terminals of the energy storage unit 12, and on the other hand connected to a tertiary terminal 16a and a quaternary terminal 16b of the module 10.

[0071] The DC / DC converter 15 can raise or lower the voltage Vc coming from the electrical energy storage unit 12.

[0072] The DC / DC converter 15 contains at least one controllable switch not shown in [Fig.l] so that it can be activated or deactivated by a command internal or external to the module 10. The DC / DC converter is also an isolated converter, which can use a transformer, in particular a transformer including windings.

[0073] The DC / DC converter 15 is also reversible, in that it is capable of converting voltage from the energy storage unit 12 to the tertiary 16a and quaternary 16b terminals and vice versa. Thus, when a voltage source applies a DC voltage to the tertiary 16a and quaternary 16b terminals, the DC / DC converter can recharge the energy storage unit 12 of the module 10.

[0074] In [Fig.2a] a chain 30 of four modules 31, 32, 33, 34 is shown. In this example each module is identical and according to module 10 of [Fig.l]. Modules 31, 32, 33, 34 are chained together by their primary and secondary terminals between the two terminals 37a 37b of the chain. More precisely, module 31 is connected to the first terminal 37a of chain 30 by its primary terminal and to the primary terminal of module 32 by its secondary terminal, module 32 is connected to the primary terminal of module 33 by its secondary terminal, module 33 is connected to the primary terminal of module 34 by its secondary terminal and module 34 is connected to the second terminal 37b of chain 30 by its secondary terminal.

[0075] The chain 30 has a single output voltage which is defined between its two terminals 37a and 37b. Regardless of the value that can be taken by this output voltage, it will be designated Vs hereinafter. In the example shown in Figure 2, the electrical energy storage units within the four modules 31, 32, 33, 34 being identical and of nominal voltage Vc, the voltage Vs can take as a value all the positive or negative integer multiples of Vcentre -4*Vc and 4*Vc when these electrical energy storage units are capable of supplying a voltage.

[0076] [Fig.2b] shows a graph 35 representing an example of alternating voltage Vs generated by the module chain 30 shown in [Fig.2a]. This generated alternating voltage Vs is capable of powering a rotating electrical machine, it is periodic with a period Ti and its shape is comparable to a sine wave.

[0077] At times 0, tb t2, and t3, the modules 31, 32, 33, 34 of the chain 30 are controlled successively so that the voltage between their terminals is equal to Vc, the maximum voltage of the generated alternating voltage Vs between two successive times becoming equal to Vc, 2* Vc, 3* Vc and 4*VC respectively. By controlling a module, we mean controlling the switches within said module in order to obtain the desired voltage between its terminals.

[0078] At times t4, t5, t6 the modules 31, 32, 33, 34 of the chain 30 are controlled successively so that the voltage between their terminals is equal to 0, the maximum voltage of the generated alternating voltage 35 between two successive times becoming equal to 3*VC, 2* Vc and Vc respectively.

[0079] The time interval between instants 0 and t7 corresponds to the positive part of the period Ti of the alternating voltage 35.

[0080] The order of control of the modules 31, 32, 33, 34 between times 0 and t7 can cor respond for example to the state of charge of the electrical energy storage unit within the modules 31, 32, 33, 34. In order to balance the state of charge of the energy storage units contained in the modules 31, 32, 33, 34, the modules can for example be controlled at times 0, tb t2, and t3 according to the decreasing order of state of charge of their electrical energy storage unit and the increasing order at times t4, t5, t6 and t7. Thus the storage unit being the most charged among the modules will be discharged for a longer time and the least charged storage unit will be discharged for a shorter time, extending the autonomy of the chain.

[0081] At times t7, t8, t9, and ti0, the modules 31, 32, 33, 34 of the chain 30 are controlled successively so that the voltage between their terminals is equal to -Vc, the maximum voltage of the generated alternating voltage 35 between two successive times becoming equal to -Vc, -2* Vc, -3* Vc and -4*VC respectively. At times tu, ti2, and tn, modules 31, 32, 33, 34 of the chain 30 are controlled successively so that the voltage between their terminals is equal to 0, the maximum voltage of the generated alternating voltage 35 between two successive times becoming equal to -3*VC, -2* Vc and -Vc respectively.

[0082] The time interval between instants t7 and tM corresponds to the negative part of the period Ti of the alternating voltage Vs.

[0083] The order of control of the modules 31, 32, 33, 34 between the times t7 and tn may correspond for example to the state of charge of the electrical energy storage unit within the modules 31, 32, 33, 34, 35. In order to balance the state of charge of the energy storage units contained in the modules 31, 32, 33, 34, the modules may for example be controlled according to the decreasing order of state of charge of their electrical energy storage unit between the times t7, t8, t9, and t10 and the increasing order at the times t1, t12, and t13.

[0084] Between two successive instants, a module can be controlled so that the voltage between its terminals successively changes from Vc to 0 and vice versa during the positive part of the period Ti or -Vc to 0 and vice versa during the negative part of the period TH, for example by pulse width modulation. This makes it possible to reduce the harmonic distortions of the generated alternating voltage 35.

[0085] The time intervals between two successive instants 0, tl, t2, t3, etc. may be all or partially identical.

[0086] [Fig.2b] shows a graph 37 representing an example of charging of the energy storage units within the modules of the chain 30 shown in [Fig.2a] when an alternating voltage Vs is applied to the terminals of said chain.

[0087] The voltage Vs shown in [Fig.2c] is a sinusoidal alternating voltage suitable for being applied to the terminals 37a 37b of the chain 30 of Figure 2. In the example shown, the voltage Vs has a maximum voltage and a minimum voltage of 4*Vcet of -4*Vcrespectively, and is periodic with a period T2. This alternating voltage can come from a charging station, connected to the terminals of chain 30.

[0088] In the example shown in [Fig.2c], during the time interval 41 between the instant O and the instant t26, the instants when the voltage Vs is zero, a module of the chain 30, for example the module 31, is controlled so that the voltage between its terminals is equal to Vc. As a result, during the time interval 41 the electrical energy storage unit of the module 31 is charged. During the time interval 42 between the instant t20 and the instant t25, the instants when the voltage 37 is equal to Vc, another module of the chain 30, for example the module 32, is controlled so that the voltage between its terminals is equal to Vc. As a result, during the time interval 42 the electrical energy storage unit of the module 32 is charged.During the time interval 43 between the instant t2i and the instant t24, the instants when the voltage 37 is equal to 2*VC, another module of the chain 30, for example the module 33, is controlled so that the voltage between its terminals is equal to Vc. As a result, during the time interval 43 the electrical energy storage unit of the module 33 is charged. During the time interval 44 between the instant t22 and the instant t23, the instants when the voltage 37 is equal to 3*VC, another module of the chain 30, for example the module 34, is controlled so that the voltage between its terminals is equal to Vc. As a result, during the time interval 44 the electrical energy storage unit of the module 34 is charged.

[0089] Similarly, during the time intervals 45, 46, 47 and 48, during the negative half-period of the period 38 of the alternating voltage Vs, the modules 31, 32, 33, 34 of the chain 30 are successively controlled so that the voltage between their primary and secondary terminals is equal to -Vcentre the instants when the alternating voltage Vs is equal to 0, -Vc, -2*VC and -3*Vc respectively so that their respective electrical energy storage unit is charged during these respective time intervals.

[0090] The order of control of the modules 31, 32, 33, 34 may correspond for example to the state of charge of the electrical energy storage unit within the modules 31, 32, 33, 34. In order to balance the state of charge of the electrical energy storage units contained in the modules 31, 32, 33, 34, the modules may for example be charged during the intervals 41, 42, 43, 44 respectively according to the increasing order of state of charge of their electrical energy storage unit. Thus, the most discharged electrical energy storage unit will be charged for a longer time and vice versa. This increasing order may be applied similarly for the intervals 45, 46, 47, 48. Balancing the recharging between the electrical energy storage units makes it possible to reduce the overall recharging time of the chain 30.

[0091] Between two successive instants, a module can be controlled so that the voltage between its terminals passes successively from Vc to 0 and vice versa during the positive part of the period 38 or -Vc to 0 and vice versa during the negative part of the period. period 36, for example by pulse width modulation. This helps reduce harmonic distortions when charging the electrical energy storage unit.

[0092] [Fig.3] represents a circuit 100, intended to be integrated within an electrically powered vehicle, using chains 30 according to [Fig.2a].

[0093] The circuit 100 comprises an input interface 101. This input interface is intended to be connected for example to a charging station for an electrically powered vehicle, capable of supplying a single- or polyphase alternating electric voltage or a direct voltage.

[0094] In the example shown in [Fig.3], the input interface 101 comprises three terminals lOlx, lOly, lOlz, capable of being connected to a respective phase of a three-phase alternating voltage. The interface 101 comprises an additional terminal lOln capable of being connected to the neutral of an alternating voltage. When a vehicle charging station connected to the input interface supplies a direct voltage or a single-phase alternating voltage, an interconnection circuit (not shown) arranged between this charging station and the input interface 101 of the circuit 100 makes it possible to distribute the voltage supplied to the three terminals lOlx, lOly and lOlz.

[0095] The circuit 100 comprises a rotating electrical machine 102. In the example shown in [Fig.3], the electrical machine 102 is a polyphase machine, comprising three phases, denoted 102x, 102y and 102z.

[0096] A control unit 109 is present in the circuit 100. The control unit 109 may be a processor or an integrated circuit, for example an FPGA or an ASIC, comprising the means for implementing the control functions of the circuit 100 and for controlling the set of switches within the circuit 100.

[0097] The circuit 100 as shown comprises a plurality of chains 103 composed of three chains 30. These three chains are according to the chain 30 shown in [Fig.2a] and are composed of a plurality of electrical modules 10 according to [Fig.l]. In this example, the chains 30 each comprise four identical modules 10 and according to the module 10 shown in [Fig.l].

[0098] In the example shown in [Fig. 3], all of the tertiary 16a and quaternary 16b terminals of all the modules 10 of the plurality of chains 103 are connected in parallel to a power supply bus 108. This power supply bus is itself connected to an interface 111, this interface 111 being intended to be connected to an electrical consumer, having a nominal voltage being for example between 8 and 48 volts, for example 12V. This consumer can be so-called low-voltage equipment of the vehicle using the circuit 100 of [Fig. 3], for example an on-board navigation system. The DC / DC converters within the modules 10 then perform a raising or lowering of the voltage of the unit of energy storage so that the voltage between terminals 16a and 16b is equal to the nominal voltage of the electrical consumer.

[0099] The strings 30 of [Fig.3] can be connected to a respective phase 102x, 102y, 102z of the electrical machine 102 by closing the switches of the plurality of switches 107.

[0100] When the strings 30 are connected to a respective phase 102x, 102y, 102z of the electrical machine 102, the control unit 59 can control the switches of the plurality of strings 103 so that they each supply an alternating voltage to the phases 102x, 102y, 102z of the electrical machine 102. As an example, this supplied voltage can be such as the voltage 35 shown in [Fig.2b], the voltages generated by the strings 30 being able to be phase-shifted by 120 degrees between them.

[0101] When the strings 30 are connected to a respective phase 102x, 102y, 102z of the electrical machine 102, and the electrical machine 102 is generating an alternating voltage, for example during regenerative braking, the control unit 109 can control the switches of the plurality of strings 103 so that the electrical energy storage units of the modules 10 can be recharged from this alternating voltage.

[0102] In the example shown in [Fig.3], the strings 30 can be connected to a respective terminal lOlx, lOly, lOlz of the input interface by closing the switches of the plurality of switches 106. When connected to the input interface, the strings are capable of receiving an alternating or direct voltage supplied by a charging terminal connected to the input interface.

[0103] In the example shown in [Fig. 3], the circuit 100 is reversible, that is to say that the control unit can control the switches within the circuit in such a way that the chains provide an alternating voltage to the terminals of the input interface 101. As an example, the chains can generate a voltage such as the voltage 35 shown in Figure 2, the voltages generated by the chains 30 being able to be phase-shifted by 120° between them.

[0104] The circuit 100 of [Fig.3] also comprises an additional chain of modules 110, the modules 10 of this chain 110 being identical to each other and according to the module 10 of [Fig.l],

[0105] In this example, the additional string 110 comprises four modules 10 arranged between its terminals. The energy storage units within the modules 10 of the additional string 110 may have a different chemical composition, size and / or nominal voltage compared to the electrical energy storage units contained in the modules 10 of the plurality of strings 103.

[0106] The terminals of the additional chain 110 are connected in parallel to an additional power supply bus 112. This additional power supply bus 112 is connected to an additional interface 113 intended to be connected to an electrical consumer, having a nominal voltage of several hundred volts, for example 400V, 800V or even more than 1000V. This consumer can be so-called high-voltage equipment of the vehicle using the circuit 100 of [Fig.3], for example a powertrain cooling system or an air conditioning system.

[0107] Thus, the modules 10 of the additional chain 110 can be controlled in such a way that they provide a direct voltage, capable of being supplied to the additional consumer intended to be connected to the additional interface 112.

[0108] The tertiary 16a and quaternary 16b terminals of the modules 10 of the additional chain 110 are connected in parallel to the power supply bus 108. This connection of the modules of the plurality of chains 103 and of the additional chain 110 to the same power supply bus, coupled with the fact that the DC / DC converter within the modules 10 is reversible, makes it possible to carry out an energy transfer between several modules 10 within the plurality of chains 103 and / or additional chain 110.

[0109] In the circuit 100 shown in [Fig.3], the supply of the additional power supply bus 112 from the input interface 101 or from the phases 102x, 102y, 102z of the stator of the rotating electrical machine 102 is carried out exclusively by transfer of electrical energy via the power supply bus 108.

[0110] The transfer of energy between several modules 10 can make it possible, in a first example, to balance the state of charge of the electrical energy storage unit between at least two modules 10, at least one first module 10 discharging its electrical energy storage unit, and at least one second module 10 charging its electrical energy storage unit. This balancing of the state of charge of the electrical energy storage units by the power supply bus 108 is advantageous because it can be carried out between two modules of two different chains, and therefore extend the general autonomy of the circuit 100.

[0111] In a second example, this energy transfer can make it possible to charge the electrical energy storage units of the modules 10 of the additional chain 110 when a charging station connected to the input interface 101 provides an alternating or direct voltage. In this case, the modules 10 of the plurality of chains 103 transfer energy to the modules of the additional chain 110. The additional chain of modules 110 not being connected to the terminals of the input interface 101, this energy transfer makes it possible to charge both the energy storage units of the plurality of chains 103 and the energy storage units of the additional chain 110.

[0112] In a third example, this energy transfer can make it possible to charge the electrical energy storage units of the modules 10 of the additional chain. 110 when the electric machine 102 is generating, for example during regenerative braking. In this case, the modules 10 of the plurality of chains 103 transfer energy to the modules of the additional chain 110. The additional chain of modules 110 not being connected to the terminals of the electric machine 102, this transfer of energy makes it possible to charge both the energy storage units of the plurality of chains 103 and the energy storage units of the additional chain 110.

[0113] In a fourth example, this energy transfer can make it possible to charge the energy storage units of the modules 10 of the plurality of chains 103 when the load connected to the additional power bus 112 is less than a predetermined threshold or zero. In this case, the modules 10 of the additional chain 110 transfer energy to the modules of the plurality of chains 103. This makes it possible to use the energy stored in the modules 10 of the additional chain 110 in order to recharge the energy storage units of the modules 10 of the plurality of chains 103 when the additional chain 110 is little used by the consumers connected to the power bus 112. The threshold value can correspond to a ratio between the energy consumed by the consumers intended to be connected to the second power bus 112 and the maximum energy that the additional chain 110 can provide, in particular the threshold value can be equal to 10%.This results in an improvement in the overall autonomy of the 100 circuit.

[0114] The invention is not limited to what has been described with reference to the figures.

[0115] Only a portion of the modules 10 of the plurality of chains 103 of the circuit 100 may comprise a DC / DC converter, and only a portion of the modules 10 may comprise a reversible DC / DC converter.

[0116] The control unit 109 may comprise a main control unit and several subsidiary control units, for example a subsidiary control unit per chain 30 and 110, and a subsidiary control unit per module 10, the functions of controlling the circuit and piloting the switches within the circuit being distributed within the main and subsidiary control units.

[0117] All or part of the modules 10 in the circuit 100 may comprise a bidirectional switching cell arranged between their primary terminal 11a and their secondary terminal 11b, this switching cell comprising at least one controllable semiconductor switch. This switching cell makes it possible to functionally disconnect the energy storage unit 12 from the terminals 11a and 11b of a module 10 by being controlled in the closed position. It is also possible to provide redundancy for the disconnection of the energy storage unit 12 from a module 10 by controlling in the closed position both the switching cell and the switches of the switching bridge 13. This redundancy makes it possible to make a module more resistant to malfunctions, for example a short circuit of a switch.

[0118] This switching cell may comprise a bidirectional transistor, for example a four-quadrant Gallium Nitride (GaN) power transistor, or two unidirectional transistors connected in antiparallel, for example MOS field effect transistors or bipolar transistors, or an electromechanical system switch.

[0119] The switches of the switching bridge 13 within the module 10 and the switching cell may be of the same type.

Claims

Claims

1. Chain (30) of modules (10) for an electrical circuit (100) comprising a first terminal (11a) and a second terminal (11b), each module (10) comprising: - a primary terminal (11a) and a secondary terminal (11b), the primary terminal (11a) being connected to the secondary terminal (11b) of another module (10) and / or the secondary terminal (11b) is connected to the primary terminal (11a) of another module (10), - an electrical energy storage unit (10), - an H-shaped switching bridge (13), the bridge (13) comprising two switching arms comprising two pilotable switches (14a, 14b, 14c, 14d) arranged on either side of a midpoint (13a, 13b), each midpoint (13a, 13b) being connected to one of the terminals (11a, 11b) of the module (10), the electrical energy storage unit (12) being arranged in a branch in parallel with the switching arms, and - at least one module (10) comprising a DC / DC converter (15), comprising controllable switches,connected on the one hand to the terminals of the electrical energy storage unit (12) and on the other hand to a tertiary terminal (16a) and to a quaternary terminal (16b) of the module (10), Characterized in that at least one DC / DC converter (15) is an isolated and reversible converter.,

2. Chain (30) according to the preceding claim, all the modules (10) of the chain (30) comprising an isolated and reversible DC / DC converter (15).

3. A string (30) according to any preceding claim, the first (11a) and second terminal (11b) defining the only output voltage of the string (30) other than voltages defined between tertiary (16a) and quaternary (16b) terminals of one of the modules (10).

4. A chain (30) according to any preceding claim, the electrical energy storage unit (12) having a nominal voltage of between 3 and 60V.

5. Chain (30) according to any preceding claim, all or part of the modules (10) comprising a bidirectional switching cell arranged between their primary terminal (11a) and their secondary terminal (11b), this switching cell comprising at least one controllable semiconductor switch.

6. A chain (30) according to any preceding claim, the unit of energy storage (12) within the modules (10) being arranged in a branch being devoid of switches.

7. Electrical circuit (100) for powering a rotating electrical propulsion machine (102) of a vehicle comprising: - a polyphase electrical machine (102), - an input interface (101) capable of being connected to a charging station, - a power supply bus (108), intended to be connected to an electrical consumer, - a plurality of strings (103) of electrical modules (10), each string (30) being according to any one of the preceding claims, - a system of switches (106, 107) allowing for each string (30) to connect it to the terminals of a phase (102x, 102y, 102z) of the electrical machine (102) or to the input interface (101), and - a control unit (109), capable of controlling the switches within the electrical circuit (100), the tertiary terminals (16a) and quaternaries (16b) of all or part of the modules (10) of the chains (30) being connected to the power bus (108).

8. Circuit (100) according to the preceding claim, the control unit (109) controlling the switches of the DC / DC converters (15) so that at least one module (10) transfers energy to at least one other module (10) via the power bus (108), the DC / DC converters (15) of these modules (10) discharging and charging their energy storage unit (12) respectively.

9. Circuit (100) according to the preceding claim, comprising a second power supply bus (112), intended to be connected to an electrical consumer with a nominal voltage higher than the nominal voltage of the consumer intended to be connected to the first power supply bus (108) and an additional string of modules (110) according to any one of claims 2 to 6, connected by its terminals (37a, 37b) to the second power supply bus (112), the tertiary (16a) and quaternary (16b) terminals of the modules (10) of the additional string (110) being connected to the first power supply bus (108).

10. Circuit (100) according to the preceding claim, the control unit (109) controlling the switches of the DC / DC converters (15) so that the modules (10) of the plurality of chains (103) transfer energy to the modules (10) of the additional string (110) by the power bus (108), the DC / DC converters (15) of the modules (10) of the plurality of strings (103) and the DC / DC converters (15) of the modules (10) of the additional string (110) discharging and charging their energy storage unit (10) respectively, when a charging station applies a voltage to the input interface (101).

11. Circuit (100) according to any one of claims 9 or 10, the control unit (109) controlling the switches of the DC / DC converters (15) so that the modules (10) of the plurality of strings (103) transfer energy to the modules (10) of the additional string (110) by the power bus (108), the DC / DC converters (15) of the modules (10) of the plurality of strings (103) and the DC / DC converters (15) of the modules (10) of the additional string (110) discharging and charging their energy storage unit (10) respectively, when the electric machine (102) operates as a generator.

12. Circuit (100) according to any one of claims 9 to 11, the control unit (109) controlling the switches of the DC / DC converters (15) so that the modules (10) of the additional string (110) transfer energy to the modules (10) of the plurality of strings (103) via the power bus (108), the DC / DC converters (15) of the modules (10) of the plurality of strings (103) and the DC / DC converters (15) of the modules (10) of the additional string (110) charging and discharging their energy storage unit (12) respectively, when the load connected to the second power bus (112) is less than a predetermined threshold or zero.

13. Circuit (100) according to any one of claims 7 to 12, the electrical energy storage units (102) contained in the modules (10) of the additional string (110) having a different chemical composition, size and / or nominal voltage compared to the electrical energy storage units (12) contained in the modules (10) of the plurality of strings (103).

14. Circuit (100) according to any one of claims 7 to 13, the number of chains (30) implemented in the plurality of chains (103) may be greater than or equal to the number of phases (12x, 102y, 102z) of the rotating electrical machine (102).

15. Circuit according to any one of claims 7 to 14, the system of switches (106, 107) being able to allow for each chain (30) to the plurality of strings (103) of connecting it to the terminals of a phase (102x, 102y, 102z) of the electrical machine (102) to which this string (30) is dedicated.

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