Power supply circuit for vehicle electrical energy storage unit

Abstract

The invention relates to an electrical circuit (6) comprising: two input terminals (13) connectable to a DC voltage; a control unit (7p, 7s); a first switching arm (B1, B3) comprising two controllable electronic switches (12) connected in series on either side of a first midpoint, the switches of the first arm being controlled by the control unit according to a first duty cycle; a second switching arm (B2, B4) comprising two controllable electronic switches (12) connected in series on either side of a second midpoint, the switches of the second arm being controlled by the control unit according to a second duty cycle; inductance units (10, 20) for contactless energy exchange consisting of inductors, mounted between first and second midpoints (14, 15), the first arms (B1, B3) and the second arms (B2, B4) being mounted in parallel, the circuit comprising a filter unit (11, 21) for filtering common and / or differential mode noise.

Description

Technical Field

[0001] This invention relates to a contactless power supply circuit for a vehicle energy storage unit. Background Technology

[0002] The energy storage unit has a nominal voltage of 12 V, 48 V, 60 V or higher, such as greater than 300 V, such as 400 V, 800 V or 1000 V.

[0003] The known approach involves supplying power ranging from 3 kW to 50 kW to the vehicle's energy storage unit via inductive coupling using contactless transmission, whether the vehicle is stationary or moving. This contactless power supply is then achieved through remote electrical sub-circuits that are magnetically coupled and tuned to the same resonant frequency. Each magnetically coupled sub-circuit implements an LC resonant element.

[0004] The solution disclosed in French application No. 22 09978, filed on September 30, 2022, which does not constitute part of the prior art, involves applying an AC voltage across the terminals of a primary inductor unit connected to a secondary inductor unit via inductive coupling, which allows electrical energy to be transferred at a low frequency to an energy storage unit, such as a battery in an electric vehicle, through impedance matching.

[0005] In this solution, large passive capacitors and inductors must be used to adapt the behavior of the inductor unit to low-frequency operation. Such components are expensive, especially at very low frequencies (e.g., less than or equal to 1000 Hz), and have equivalent series resistance (ESR). The value of these ESRs can lead to parasitic behaviors that can affect the efficiency of power transfer. Summary of the Invention

[0006] The present invention aims to allow low-frequency inductive loads without the aforementioned disadvantages, and according to one aspect of the invention, the object of the invention is an electrical circuit comprising: Two input terminals, which can be connected to a DC voltage; Control unit; The first switch arm includes two controllable electronic switches connected in series on both sides of the first midpoint, and the switch of the first arm is controlled by the control unit with a first duty cycle. The second switch arm includes two controllable electronic switches connected in series on both sides of the second midpoint. The switching of the second arm is controlled by a control unit with a second duty cycle. An inductor unit used for non-contact energy exchange, which is composed of inductors; The inductor unit is installed between the first midpoint and the second midpoint; The first and second arms are installed in parallel; The control unit is configured to operate on a first duty cycle and a second duty cycle in such a way that the voltage between the first midpoint and the second midpoint simulates the presence of an inductor and a capacitor mounted in series with the inductor unit. The circuit includes a filtering unit for filtering common-mode noise and / or differential-mode noise, the unit comprising: Two magnetically coupled inductors, each connected in series between the midpoint of the switch arm and the terminals of the inductor unit; and At least one of a capacitor arranged in parallel with the inductor and a capacitor arranged between the terminals of the inductor and ground.

[0007] The circuit defined above eliminates the need for physical capacitors and inductors by controlling the switching arm, while achieving electrical behavior equivalent to that obtained with such physical components. Therefore, the present invention benefits from the existence of existing voltage converters to add additional functionality to them. This, in turn, reduces the cost and size of the circuit.

[0008] However, eliminating these physical components by switching the switching arm can cause high-frequency components to propagate in the voltage across the terminals of the inductor unit (even at low levels). This propagation occurs in both differential and common modes and produces parasitic behavior.

[0009] Therefore, since there is a filtering unit for filtering common-mode noise and / or differential-mode noise, the circuit defined above also overcomes the disadvantages associated with removing the inductors and capacitors that are now being simulated.

[0010] Therefore, this invention allows for the removal of bulky capacitors and inductors (simulating the behavior of capacitors and inductors) and allows for filtering of any high frequency using inductors and one or more smaller and cheaper capacitors. The capacitors and inductors replaced by the simulation will have a value, for example, that is at least 5 times, and especially at least 10 times, the product of the inductors and capacitors in a filter unit used for filtering common-mode noise and / or differential-mode noise. For example, the capacitors and inductors replaced by the simulation will have a value that is at least 5 times, and especially at least 10 times, the product of any inductor and any capacitor in a filter unit used for filtering common-mode noise and / or differential-mode noise.

[0011] Two magnetically coupled inductors can be obtained, for example, by two coils wound on the same magnetic core. Other methods can also be used to obtain two magnetically coupled inductors.

[0012] This control allows for the simulation of inductors and capacitors while keeping the values ​​constant.

[0013] Compared to inductors and capacitors connected in series, control performed by the control unit can more broadly allow the simulation of complex impedances connected in series with the inductor unit, such as impedances with negative inductance, impedances with negative capacitance, or impedances of inductors with values ​​that change over time or impedances of capacitors with capacitance values ​​that change over time.

[0014] The voltage between the two midpoints can correspond to the voltage applied to a series mount that includes the following: Inductor unit; Analog inductor; Analog capacitors; and The filter unit has two magnetically coupled inductors.

[0015] The electrical circuit according to the invention may include a current sensor mounted in series with an inductor unit. For example, the current sensor is arranged such that mounting between a first midpoint and a second midpoint of the electrical circuit involves a series connection of two inductors magnetically coupled around the inductor unit and the current sensor. This series branch also includes an analog inductor and an analog capacitor.

[0016] According to a first variant of the invention, the two input terminals are connected to a voltage network via an AC / DC converter. According to this first variant, two switching arms define the DC / AC converter, thereby allowing an AC voltage to be present across the terminals of the inductor unit.

[0017] The electrical network provides a nominal RMS voltage of, for example, 230 V or 110 V, with a frequency of 50 Hz or 60 Hz. The electrical network is, for example, single-phase.

[0018] An electricity network can be, for example, a regional or national electricity network. As a variation, an electricity network can be a standalone local network, comprising, for example, one or more batteries powered by energy sources such as wind turbines, solar panels, fuel cells, or hydroelectric generators.

[0019] According to a second variant of the invention, two input terminals of the electrical circuit are connected to the energy storage unit. According to this second variant, two switching arms define the DC / AC converter, thereby allowing impedance matching at the AC input terminals of the converter, independent of the impedance of the energy storage unit. This impedance matching can be performed as follows: One of the first and second switching arms switches at a frequency of non-contact energy exchange; and One of the first and second arms can switch at a higher frequency, for example, at a frequency equal to or greater than 5 or 10 times the frequency of contactless energy exchange. One of the switching arms switches at a frequency of contactless energy exchange, for example, with a 50% duty cycle, and the other switching arm switches at a frequency equal to or greater than the frequency of energy transfer from the primary circuit (especially equal to or greater than 5 or 10 times the frequency of energy transfer from the primary circuit) and with a duty cycle modulated according to the measured AC current and the voltage at the AC input terminals of the two switching arms. This implementation of impedance matching of the two switching arms of a DC / AC converter is described, for example, in the applicant's application FR 3 140 490. The contents of that application are incorporated herein by reference for how the two switching arms are controlled, wherein an inductor unit is mounted between the midpoints of the switching arms to perform impedance matching.

[0020] The energy storage unit can typically be a lithium-ion battery. This battery has a nominal voltage of, for example, 12 V, 48 V, 60 V or higher, such as greater than 300 V, such as 400 V, 800 V or 1000 V.

[0021] The filtering unit can be used to filter common-mode noise and differential-mode noise. In addition to the two magnetically coupled inductors mentioned above, this unit also includes: A first capacitor, which is arranged in parallel with the inductor unit; A second capacitor is disposed between the first terminal of the inductor unit and ground; and The third capacitor is arranged between the second terminal of the inductor unit and ground.

[0022] When a first and second capacitor are present, and in the absence of a third capacitor, the two existing capacitors may already provide differential filtering. In appropriate cases, this differential filtering may not require the presence of a third capacitor.

[0023] When the aforementioned current sensor and inductor unit are connected in series, the first capacitor can be connected in parallel with the series connection of the current sensor and inductor unit. Similarly, in this case, the current sensor can be installed between the sensing unit and the connection point to the second or third capacitor.

[0024] Typically, the capacitance of the first capacitor is less than or equal to 1 mF and greater than or equal to 10 nF, and the capacitance of the second and / or third capacitor is less than or equal to 1 mF and greater than or equal to 10 nF.

[0025] Because the capacitance is low, the second and third capacitors can be Y capacitors. The first capacitor is, for example, an X capacitor.

[0026] Typically, each of the inductors in the filter unit has a value less than or equal to 1 mH and greater than or equal to 100 nH.

[0027] Typically, the magnetic coupling rate between the two inductors of a filter unit can take any value between 0% and 100%, including extreme values.

[0028] The present invention also relates to a power supply circuit for an energy storage unit, the power supply circuit comprising: The first circuit, referred to as the "primary circuit" as described above; The second circuit, referred to as the "secondary circuit" as described above; The control units for the primary and secondary circuits are configured to operate at a first duty cycle and a second duty cycle for each circuit, in such a way that: The voltage between the first and second midpoints of the primary circuit is analogous to the presence of an inductor and capacitor connected in series with the primary inductor unit; and The voltage between the first and second midpoints of the secondary circuit simulates the presence of an inductor and capacitor connected in series with the secondary inductor unit; The inductors in the primary circuit and the secondary circuit are configured to exchange electrical energy non-contactly through inductive coupling.

[0029] By adjusting the control laws of the DC / AC converters in the primary and secondary circuits respectively, the voltage between the first and second midpoints of the primary circuit and the voltage between the first and second midpoints of the secondary circuit can be obtained respectively. This voltage behaves as if it were applied to a component comprising a primary inductor unit and a secondary inductor unit connected in series with an inductor and a capacitor respectively. In addition, there is a filtering unit for filtering common-mode noise and / or differential-mode noise.

[0030] Therefore, this circuit allows the removal of bulky capacitors and inductors (simulating the behavior of capacitors and inductors) and allows filtering of high frequencies using inductors and one or more smaller and cheaper capacitors.

[0031] To allow contactless energy exchange between the primary and secondary circuits, the inductors in the primary and secondary circuits are configured to exchange energy contactlessly via inductive coupling.

[0032] Where appropriate, these physical coils and the components whose behavior is simulated are selected in such a way that the inductors of the primary circuit and the inductors of the secondary circuit have substantially the same resonant frequency.

[0033] Non-contact power exchange via inductive coupling occurs, for example, at frequencies below 10 kHz, such as 7 kHz, such as 5 kHz, such as below 3 kHz, or even below 2 kHz or 1 kHz, especially at frequencies still substantially equal to 400 Hz or 50 Hz.

[0034] As a variant, contactless power exchange via inductive coupling can be performed at a frequency of 85 kHz.

[0035] Throughout the above, the control unit can be configured to control each switch arm selectively: The energy storage unit is charged from the voltage network; or The voltage network is charged from the energy storage unit.

[0036] Therefore, electrical energy can be exchanged in one direction or the other as needed.

[0037] In all of the above, each controllable electronic switch is, for example, a transistor (e.g., a bipolar, MOS, or IGBT transistor) or a thyristor. For example, each controllable electronic switch is bidirectional.

[0038] In all of the above, each control unit can be a digital processing circuit, such as an ASIC (Application-Specific Integrated Circuit) or a microcontroller.

[0039] As a variant, a single control unit (e.g., a digital processing circuit) can be provided, which controls the switching arms of the primary and secondary circuits.

[0040] As another variant, the control unit is shared by the primary and secondary circuits, and the control unit includes a primary circuit control module and a secondary circuit control module.

[0041] According to another aspect of the invention, another object of the invention is a component for powering an energy storage unit, the component comprising the electrical circuitry defined above, the component particularly defining a structure supporting a primary circuit and a secondary circuit, such that the primary circuit and the secondary circuit are rigidly connected to each other. Such a component is commonly referred to as an "on-board charger." This component can be mounted on a hybrid or electric vehicle.

[0042] According to another aspect of the invention, another object of the invention is a device for supplying power to an energy storage unit, the device comprising: Charging stations for hybrid or electric vehicles, wherein the primary circuitry of the electrical circuit described above is arranged in or connected to the charging station; and A component capable of being mounted on a hybrid or electric vehicle, wherein the secondary circuitry of the electrical circuit described above is arranged in the component.

[0043] The terminal then receives electrical power from the power network via a cable, which can be a single-phase or three-phase cable. In this case, the primary and secondary circuits are not integrated into the same physical component. Attached Figure Description

[0044] The invention will be better understood by reading the following description of non-limiting embodiments thereof and by referring to the accompanying drawings, in which: Figure 1 An electrical circuit according to an embodiment of the present invention is illustrated schematically; Figure 2 An electrical circuit including inductive and capacitive components that can be simulated by the present invention is illustrated schematically. Detailed Implementation

[0045] Figure 1 A power supply circuit 1 for an energy storage unit 2 is shown. The energy storage unit 2 is, for example, a vehicle battery, which may have a nominal voltage of 48 V, 60 V, 300 V, 400 V, 800 V, or greater. This invention is used to power the drive system of an electric vehicle or a hybrid vehicle.

[0046] The power supply circuit 1 includes: Primary circuit 4, which is connected to voltage network 5; and Secondary circuit 6, which is connected to energy storage unit 2.

[0047] The power supply circuit 1 implements contactless power exchange through inductive coupling between the primary circuit 4 and the secondary circuit 6 in order to charge the power storage unit 2.

[0048] In the example under consideration, primary circuit 4 includes: Two input terminals 13 are connected to AC / DC converter 9, which in turn is connected to voltage network 5. Primary control unit 7p; The first switch arm B1 includes two controllable electronic switches 12 connected in series on both sides of the first midpoint 14. The switching of the first arm is controlled by the primary control unit 7p with a first duty cycle αp1. The second switch arm B2 includes two controllable electronic switches 12 connected in series on both sides of the second midpoint 15. The switching of the second arm is controlled by the primary control unit 7p with a second duty cycle αp2. A primary inductor unit 10 for contactless energy exchange, in this case, the inductor unit is composed of an inductor and is installed between a first midpoint 14 and a second midpoint 15.

[0049] like Figure 1 As shown, the first switch arm B1 and the second switch arm B2 are installed in parallel.

[0050] Electrical network 5 provides, for example, a nominal RMS voltage of 230 V, with a frequency of 50 Hz or 60 Hz. In this case, voltage network 5 is single-phase, making the voltage across the terminals of AC / DC converter 9 also single-phase.

[0051] In this case, each switching arm B1 and B2 of the primary circuit 4 includes two controllable electronic switches 12 mounted in series, such as MOS, IGBT, bipolar transistor, or thyristor.

[0052] The first arm B1 therefore includes two controllable electronic switches 12 connected in series, with the first terminal of the primary inductor unit 10 for non-contact energy exchange connected between the two controllable electronic switches.

[0053] The second arm B2 therefore includes two controllable electronic switches 12 connected in series, with the first terminal of the primary inductor unit 10 for non-contact energy exchange connected between the two controllable electronic switches.

[0054] The two arms B1 and B2 are cascaded together with the AC / DC converter 9.

[0055] according to Figure 1 In the illustrated embodiment, the primary circuit 4 includes a primary current sensor 8p mounted in series with the primary inductor unit 10. This primary current sensor 8p can advantageously transmit information about the measured current to the primary control unit 7p.

[0056] In this case, the primary control unit 7p is configured to operate at the first duty cycle αp1 and the second duty cycle αp2 in such a way that the voltage between the two midpoints 14 and 15 of the primary circuit 4 simulates the presence of an inductor and capacitor connected in series with the primary inductor unit 10.

[0057] In this configuration, the primary inductor unit 10 is formed from a coil used to generate magnetic energy. Controlling the duty cycle using the primary control unit 7p allows the behavior of a capacitor to be simulated, thus forming a resonant unit. For example, the coil has an inductance ranging from 1 mH to 100 mH, and the capacitor, whose behavior is simulated by controlling the duty cycle using the primary control unit 7p, has a capacitance ranging from 100 µF to 100 mF.

[0058] like Figure 1 As shown, the primary circuit also includes a filter unit 11, which filters common-mode noise and differential-mode noise in the example under consideration.

[0059] In this case, the filtering unit 11 includes: Two magnetically coupled inductors 17a and 17b are connected in series between the midpoints 14 and 15 of the switch arm and the terminals of the inductor unit 10. The first capacitor 16 is arranged in parallel with the inductor unit 10; The second capacitor 18a is arranged between the first terminal of the inductor unit 10 and ground. The third capacitor 18b is arranged between the primary current sensor 8p and ground.

[0060] In the example under consideration, the capacitance of the first capacitor 16 is less than or equal to 1 mF and greater than or equal to 10 nF, and this capacitor is an X capacitor. Similarly, in this example, the capacitances of the second capacitor 18a and the third capacitor 18b are less than or equal to 1 mF and greater than or equal to 10 nF, and these capacitors are Y capacitors.

[0061] In the same example, the inductors 17a and 17b of the filter unit 11 each have values, for example, less than or equal to 1 mH and greater than or equal to 100 nH.

[0062] Now refer to Figure 1 An example describing secondary circuit 6. In the considered example, secondary circuit 6 includes: Secondary inductor unit 20 for contactless energy exchange, in which case the secondary inductor unit is formed by an inductor; AC / DC converter 23, which is capable of performing equivalent impedance matching at its AC input (and therefore on one side of the secondary sensing unit 20) so that the impedance varies independently of the impedance of the energy storage unit 2; and Secondary control unit 7s.

[0063] like Figure 1 As shown, the AC / DC converter 23 includes: The first switch arm B3 includes two controllable electronic switches 12 connected in series on both sides of the first midpoint 14. The switching of the first arm is controlled by the secondary control unit 7s with a first duty cycle αs1. The second switch arm B4 includes two controllable electronic switches 12 connected in series on both sides of the second midpoint 15. The switch of the second arm is controlled by the secondary control unit 7s with a second duty cycle αs2.

[0064] like Figure 1 As shown, the first switch arm B3 and the second switch arm B4 are installed in parallel, and the secondary inductor unit 20 is connected between the two midpoints 14 and 15 of the AC / DC converter 23.

[0065] Figure 1 The AC / DC converter 23 in the middle is controlled, for example, by the secondary control unit 7s, as follows, so as to perform impedance matching at the AC input terminal of the converter 23: One of the two arms, B3 or B4, switches between them at a non-contact energy exchange frequency and with a 50% duty cycle; and The other arm of the two arms B3 or B4 switches at a frequency greater than the frequency of non-contact energy exchange (e.g., at least 5 or 10 times the frequency of non-contact energy exchange) and with a duty cycle that is modulated based on the AC current measured at the output of the secondary inductor unit 20 and based on the voltage across the terminals of the AC input of the AC / DC converter 23.

[0066] The secondary control unit 7s is configured to operate at a first duty cycle and a second duty cycle in such a way that the voltage between the first midpoint 14 and the second midpoint 15 of the secondary circuit 6 simulates the presence of an inductor and a capacitor connected in series with the secondary inductor unit 20.

[0067] Advantageously, the electrical circuit according to the invention allows for obtaining a connection with the switch arms B1 to B4 by controlling the switch arms B1 to B4. Figure 2 The illustrated electrical circuit equivalent effect, wherein according to the invention, this effect occurs without... Figure 2 The results are obtained with capacitors Cp and Cs and inductors Lp2 and Ls2.

[0068] exist Figure 2 In the circuit shown, the primary circuit 4 has a series connection between the primary impedance Zp and the primary inductor unit Lp1 between its two midpoints 14 and 15. In this case, the primary impedance Zp includes the inductor Lp2 and the capacitor Cp connected in series.

[0069] exist Figure 2In the circuit shown, the secondary circuit 6 has a secondary impedance Zs connected in series with the secondary inductor unit Ls1 between its two midpoints 14 and 15. In this case, the secondary impedance Zs includes an inductor Ls2 and a capacitor Cs connected in series.

[0070] The coupling between the primary and secondary inductor units allows for contactless power transfer between the primary and secondary circuits. Advantageously, for example, as... Figure 1 As shown, the electrical circuit according to the present invention allows for simulation using a switch arm already present in prior art circuits: The presence of the primary impedance Zp connected in series with the primary inductor unit 10 on the primary circuit side; and The presence of the secondary impedance Zs connected in series with the secondary inductor unit 20 on the secondary circuit side No components with physical primary and secondary impedances are required.

[0071] Due to voltage (αp1-αp2) Vdc, where Vdc is the voltage between the two input terminals 13 of the primary circuit, and the primary control unit 7p allows the simulation of an inductor and capacitor connected in series with the primary inductor unit 10 between the first midpoint 14 and the second midpoint 15 of the switching arms B1 and B2.

[0072] As described above, there is an assembly between the first midpoint 14 and the second midpoint 15 of the switching arms B1 and B2 of the primary circuit 4. This assembly includes, in series: a primary inductor unit 10, a current sensor 8p, and two coupled inductors 17a and 17b of the filter unit 11, surrounding the primary inductor unit 10 and the current sensor 8p. The assembly also includes analog inductors and analog capacitors connected in series with the aforementioned components; however, these analog components are not... Figure 1 As shown in the image.

[0073] Additionally, for (αs1 - αs2) Vbatt, where Vbatt is the voltage across the terminals of the energy storage unit 2, can simulate a capacitor and inductor connected in series with the secondary inductor unit 20 between the first midpoint 14 and the second midpoint 15 of the switching arms B3 and B4.

[0074] As described above, there is an assembly between the first midpoint 14 and the second midpoint 15 of the switching arms B3 and B4 of the secondary circuit 6. This assembly includes, in series, two coupled inductors 24a and 24b of the secondary inductor unit 20, the current sensor 8s, and the filter unit 21, surrounding the primary inductor unit 20 and the current sensor 8s. The assembly also includes analog inductors and analog capacitors connected in series with the aforementioned components; however, these analog components are not... Figure 1 As shown in the image.

[0075] Advantageously, the physical coils in the inductor unit are limited to maximize the coupled inductance value, since the uncoupled portions of these inductors that can be used for resonance are simulated by the control units of the primary and secondary circuits.

[0076] The invention has been described above using embodiments shown in the accompanying drawings, but this does not limit the overall inventive concept.

[0077] Many other modifications and variations will become apparent to those skilled in the art after considering the various embodiments shown in this application.

[0078] These embodiments are provided by way of example and are not intended to limit the scope of the invention, which is defined only by the following claims.

[0079] In the claims, the term "comprising" does not exclude other elements or steps, and the use of the indefinite article "a" or "an" does not exclude multiple.

[0080] The mere fact that various features are listed in the dependent claims does not imply that combinations of these features can be used advantageously. Finally, any references used in the claims should not be construed as limiting the scope of the invention.

Claims

1. An electrical circuit (4, 6) comprising: two input terminals, connectable to a DC voltage; a control unit (7p, 7s); a first switching arm (Bl, B3) comprising two controllable electronic switches (12) in series on both sides of a first midpoint (14), the switches of this first arm being controlled by the control unit with a first duty cycle; a second switching arm (B2, B4) comprising two controllable electronic switches (12) in series on both sides of a second midpoint (15), the switches of this second arm being controlled by the control unit with a second duty cycle; an inductive unit (10, 20) for contactless energy exchange, the inductive unit being made up of an inductor; the inductive unit (10, 20) being mounted between the first and second midpoints (14, 15); the first (Bl, B3) and second (B2, B4) arms being mounted in parallel; the control unit (7p, 7s) being configured to act on the first and second duty cycles in such a way that the voltage between the first and second midpoints (14, 15) simulates the presence of an inductor and a capacitor mounted in series with the inductive unit (10, 20), wherein the circuit comprises a filtering unit (11, 21) for filtering common mode and / or differential mode noise, the unit comprising: two inductors (17a, 17b, 24a, 24b) coupled magnetically, each inductor being arranged in series between a midpoint (14, 15) of a switching arm and a terminal of the inductive unit (10, 20); and at least one of a capacitor (16, 26) arranged in parallel with the inductive unit and a capacitor (18a, 18b, 28a, 28b) arranged between a terminal of the inductive unit and ground.

2. The electrical circuit of claim 1, wherein, the filtering unit (11, 21) being a unit for filtering common mode and differential mode noise, the unit comprising: a first capacitor (16, 26) arranged in parallel with the inductive unit (10, 20); a second capacitor (18a, 28a) arranged between a first terminal of the inductive unit and ground; and a third capacitor (18b, 28b) arranged between a second terminal of the inductive unit and ground.

3. The electrical circuit of claim 2, wherein, the capacitance of the first capacitor (16) being less than or equal to 1 mF and greater than or equal to 10 nF.

4. The electrical circuit of claim 2 or 3, wherein, the capacitance of the second capacitor (18a, 28a) and / or the capacitance of the third capacitor (18b, 28b) being less than or equal to 1 mF and greater than or equal to 10 nF.

5. The electrical circuit of any of claims 2 to 4, wherein, the first capacitor (16, 26) being an X capacitor and wherein the second capacitor (18a, 28a) and the third capacitor (18b, 28b) are Y capacitors.

6. The electrical circuit of any of the preceding claims, wherein, each of the inductors (17a, 17b, 24a, 24b) of the filtering unit (11, 21) has a value less than or equal to 1 mH and greater than or equal to 100 nH.

7. The electrical circuit of any of the preceding claims, wherein, The two input terminals (13) are connected to a voltage network (5) via an AC / DC converter.

8. The electrical circuit of any one of claims 1 to 6, wherein, The two input terminals (13) are connected to an electrical energy storage unit (2).

9. The electrical circuit of claim 8, wherein, The two switch arms define a DC / AC converter, allowing impedance matching on the AC input of the DC / AC converter independently of the impedance of the electrical energy storage unit (2), One of the first and second switch arms is switched at the frequency of the contactless energy exchange; and The other of the first and second arms is switched at a frequency greater than or equal to 5 or 10 times the frequency of the contactless energy exchange.

10. A power supply circuit for an electrical energy storage unit (2), comprising: a first electrical circuit, called "primary circuit (4)", as claimed in any one of claims 1 to 7 ； a second electrical circuit, called "secondary circuit (6)", as claimed in any one of claims 1 to 6 or 8 or 9; the control units of the primary and secondary circuits are configured to act on the first and second duty cycles of each circuit in such a way that: the voltage between the first and second midpoints (14, 15) of the primary circuit (4) is analogous to the presence of an inductor and a capacitor installed in series with the inductive unit (10) of the primary circuit (4); and the voltage between the first and second midpoints (14, 15) of the secondary circuit (6) is analogous to the presence of an inductor and a capacitor installed in series with the inductive unit (20) of the secondary circuit (6); the inductive units (10) of the primary circuit (4) and (20) of the secondary circuit (6) are configured to exchange electrical energy contactlessly by inductive coupling.

11. A device for powering an electrical energy storage unit (2), comprising: a charging station for a hybrid or electric vehicle, the primary circuit of the electrical circuit as claimed in claim 10 being arranged in or connected to the charging station; and a component capable of being placed on board a hybrid or electric vehicle, the secondary circuit of the electrical circuit as claimed in claim 10 being arranged in the component.

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