FR3096845A1 - Power electronic system for converting at least an input voltage to a continuous output voltage, and corresponding method - Google Patents

Abstract

Power electronic system for converting at least one input voltage into a continuous output voltage, and corresponding method System (power electronics comprising at least one module (CV1) adapted to be connected to a voltage source delivering a voltage of input (Ue1) continuous between a positive terminal (AA1) and a negative terminal (BB1), and to transform the input voltage into an output voltage (Us1) continuous between a first output (CC1) and a second output (DD1) ) of the module.The module comprises: - a switching circuit (3) comprising a first input (E1) and a second input (E2) intended to be connected respectively to the positive terminal and to the negative terminal of the voltage source, - a first filter circuit (5) having a first input (E6) connected to a first output (E3) of the switching circuit, and a second input (E7) intended to be connected to the negative terminal of the voltage source, and - a second circu it filter (7) having a first input (E10) connected to a first output (E8) of the first filter circuit, a second input (E11) connected to a second output (E9) of the first filter circuit, a first output (E12) connected to the first output (CC1) of the module, and a second output (E13) connected to the second output (E4) of the switching circuit, the second output (E9) of the first filter circuit being further connected to the second output (DD1) of the module. Corresponding process. Figure for the abstract: Figure 2

Description

Power electronic system for converting at least one input voltage into a DC output voltage, and corresponding method

The present invention relates to a power electronic system comprising at least one module suitable for being connected to a voltage source delivering a DC input voltage between a positive terminal and a negative terminal, and for transforming the input voltage into a voltage continuous output between a first output and a second output of the module, the module comprising a switching circuit comprising a first input and a second input intended to be connected respectively to the positive terminal and to the negative terminal of the voltage source.

The invention also relates to a corresponding conversion method.

With the advent of renewable energies, the proliferation of electrical energy sources and the development of on-board systems, the need to make several electrical energy sources of different kinds work together has increased. The action of connecting together several sources of electrical energy does not pose a problem when the latter have identical output voltages to each other. On the other hand, the problem becomes more complicated when the output voltages are different.

Thus, to sum the electrical powers produced by electrical sources whose output voltages are different, it is known to associate with each of the sources an electronic circuit to convert each of the voltages of the electrical sources into output voltages having a predefined magnitude .

To do this, chopper circuits comprising one or more switching cells are used, for example voltage booster circuits (known in English under the name “boost”), or voltage step-up/step-down circuits (known in English under the name “boost”). name of "buck-boost").

However, these conversion circuits cause energy losses, i.e. the electrical power recovered at the output of one of these circuits is slightly lower than the electrical power delivered by the voltage source. This results in a fairly significant loss of energy when one wishes to sum the electrical powers of several generators with different voltage levels.

In addition, due to the presence of one or more switching cells, these conversion circuits create instabilities in the output voltages, which it would be desirable to reduce.

An object of the invention is therefore to provide a conversion circuit that can be connected to a voltage source and adapted to provide an output voltage having a predefined magnitude, and this with reduced energy losses compared to the chopper circuits of the state of technology, all other things being equal.

To this end, the subject of the invention is an electronic power system of the type described above, in which the module further comprises:

- a first filter circuit having a first input connected to a first output of the switching circuit, and a second input intended to be connected to the negative terminal of the voltage source, and

- a second filter circuit having a first input connected to a first output of the first filter circuit, a second input connected to a second output of the first filter circuit, a first output connected to the first output of the module, and a second output connected to the second output of the switching circuit, the second output of the first filter circuit being further connected to the second output of the module.

According to particular embodiments, the system according to the invention comprises one or more of the following characteristics, taken in isolation or in all technically possible combinations:

- the first filter circuit and the second filter circuit are structurally analogous to each other;

- the first filter circuit and/or the second filter circuit respectively comprises several inductors and several capacitors, and is preferably an “LC” circuit;

- each of the first filter circuit and of the second filter circuit comprises a first branch directly connecting its first input to its first output, and a second branch directly connecting its second input to its second output, each of the first branch and the second branch comprising at least one inductance, preferably of the same value;

- each of the first filter circuit and of the second filter circuit comprises a third branch directly connecting its first input to its second output, and a fourth branch directly connecting its second input to its first output, each of the third branch and the fourth branch comprising at least one capacitor, preferably of the same value;

- the switching circuit forms a voltage booster circuit or a voltage step-up/step-down circuit, when the second output of the switching circuit is connected directly to the negative terminal of the voltage source;

- the switching circuit comprises at least one storage inductor and at least one switching cell;

- when said switching cell is in a closed state, the storage inductance is in series with an inductance of the first filter circuit, with an inductance of the second filter circuit, and with the voltage source;

- the system further comprises at least one second DC voltage source, the first output and the second output of the module being connected in series or in parallel with the second DC voltage source; and

- the system comprises at least one second module structurally analogous to the module and intended to be connected at the input to at least one second voltage source adapted to deliver a second DC input voltage, the second module being adapted to transform the second voltage d entry into a second DC output voltage between a first output and second output of the second module, the first output and the second output of the second module being connected in series or in parallel with the first output and the second output of the module.

The invention also relates to a conversion method implementing a system as described above,

- the module being connected to the voltage source delivering the input voltage to transform the input voltage into the output voltage, or

- the system comprising a plurality of modules structurally analogous to one another and respectively connected to voltage sources delivering input voltages, each of the modules delivering a DC output voltage, the modules being connected so that their respective output voltages are in series or parallel to each other.

The invention will be better understood on reading the following description, given solely by way of example, and made with reference to the appended drawings, in which:

FIG. 1 is a schematic representation of a system according to the invention, comprising a plurality of modules structurally analogous to one another and respectively connected to voltage sources delivering input voltages, the modules being connected to set their output voltages respective in series to deliver in a load,

Figure 2 is an electrical circuit illustrating the structure common to the modules shown in Figure 1,

FIG. 3 is a voltage-raising chopper circuit (“boost”) from which the switching circuit of the structure represented in FIG. 2 derives,

FIG. 4 is a circuit similar to that represented in FIG. 2, further showing the operation of the modules during two phases corresponding respectively to the closing and the opening of the switching cell of the switching circuit of the module,

Figure 5 shows a variant of the module shown in Figures 2 and 4,

FIG. 6 is a graph showing the evolution of the ratio of the output voltage divided by the input voltage of the module represented in FIGS. 2 and 4 as a function of a duty cycle of the switching circuit, and in comparison with this that allows the conventional chopper circuit shown in Figure 3, the ratio between the load resistance and the resistance of a storage induction of the switching circuit being equal to 5000,

[Fig 8] Figures 7 and 8 are graphs similar to that shown in Figure 6, the ratio of the load resistance divided by the resistance of the storage inductor being equal to 100 and 10 respectively,

Figure 9 is a graph illustrating the energy efficiency of the system shown in Figure 1 reduced to three modules and three voltage sources, compared to a system in which each of the modules is replaced by the conventional chopper circuit shown in Figure 3 ,

FIG. 10 is a graph representing the evolution of the ratio of the output voltage of this system with three modules divided by the sum of the input voltages, and also in comparison with the system with three conventional chopper circuits,

Figure 11 is a graph showing the output voltage generated by the module shown in Figure 2, and

Fig. 12 is a graph showing the output voltage of the conventional chopper shown in Fig. 3 under the same operating conditions.

With reference to FIG. 1, a system 1 according to the invention is described.

System 1 is a power electronic system adapted so that a plurality of voltage sources S1, S2, ... Sn can work together to deliver electrical power to a load Rch, for example an electrical resistor.

The system 1 comprises a plurality of modules CV1, CV2, … CVn respectively connected at the input to the voltage sources S1… Sn.

By “connected”, we mean in this document “electrically connected” when it comes to electrical or electronic components, or contact points (such as inputs or outputs).

Each of the voltage sources Si, i being an integer between 1 and n, is adapted to deliver a continuous input voltage Uei between a positive terminal AAi and a negative terminal BBi. Each of the voltage sources Si is for example directly a DC voltage source, or, as a variant, comprises an AC voltage source and a rectifier.

The voltage sources Si include, for example, solar panels, or electrical power generators forming part of a tidal turbine (device not shown capable of converting the power of a liquid flow into electrical power).

The voltages Uei (with i = 1, 2…n) are DC voltages in the electrical sense of the term, i.e. they are not alternating. However, they are not constant.

Each of the modules CVi is connected at the input to the terminals AAi and BBi of the voltage source Si. Each of the modules CVi is suitable for delivering an output voltage Usi between a first output CCi and a second output DDi of the module.

The modules CVi are advantageously connected to each other so that the output voltages Usi are in series with each other and their sum forms an output voltage Us of the system 1 at the terminals of the load Rch.

Each of the voltage sources Si is adapted to send a current Ii into the module CVi and to receive the same current from this module.

The system 1 is adapted to cause a current I to flow in the load Rch.

The current I leaves the module CV1 by the first output CC1, crosses the load Rch, then enters the module CVn by the second output DDn.

Each of the second outputs DDi is connected directly to the first output CCi+1 and receives the current I from this first output. In other words, the second output of a module is connected to the first output of the neighboring module located below in figure 1.

FIG. 1 therefore illustrates a series connection on the output side of the CVi modules.

According to a variant not shown, the outputs of the CVi modules are connected in parallel with each other. The output voltages Usi are then equal to each other and the currents which leave the modules CVi by the first outputs CCl are added, their sum passing through the load Rch.

According to another variant not represented, the system 1 comprises only the module CV1 and the voltage source S1. In this case, the CV1 module is simply adapted to convert the input voltage Ue1 into the output voltage Us1.

According to yet another variant (not shown), the system 1 comprises the module CV1, the voltage source S1, and the voltage source S2, the input voltage Ue2 being mounted in series or in parallel directly with the output voltage Us1.

According to particular embodiments, the system 1 comprises two, three or more CVi modules.

In the example shown in Figure 1, the CVi modules are structurally similar to each other, so only the CV1 module will be described in detail below with reference to Figure 2.

Module CV1 includes a switching circuit 3, a first filter circuit 5, and a second filter circuit 7.

The switching circuit 3 is a circuit for switching the input voltage and giving at its output a voltage of different mean value.

Switching circuit 3 comprises two inputs E1 and E2 connected respectively to positive terminal AA1 and to negative terminal BB1 of voltage source S1. Switching circuit 3 also includes a first output E3 and a second output E4.

In the example shown, the switching circuit 3 is analogous to the "boost" chopper circuit shown in Figure 3, except that the second output E4 is not directly connected to the second input E2. Indeed, in the module CV1, the second output E4 is connected to the first input E2 and to the negative terminal BB1 only indirectly, via the first filter circuit 5 and the second filter circuit 7.

The switching circuit 3 nevertheless forms a chopper circuit suitable for delivering a chopped voltage between the midpoint E5 and the second output E4. Voltage Un between first output E3 and second output E4 is smoothed by capacitor Cdc2.

In the example represented, the switching circuit 3 comprises a storage inductor L and a diode D connected in series between the first input E1 and the first output E3, these two elements defining between them a midpoint E5. The switching circuit also comprises a switching cell K arranged between the midpoint E5 and the second output E4, a capacitor Cdc2 connecting the first output E3 and the second output E4, and optionally a capacitor Cdc1 connecting the first input E1 and the second E2 input.

The storage inductor L has an internal resistance RL and is located between the first input E1 and the midpoint E5.

Diode D is located between the first output E3 and the midpoint E5. Diode D is a power diode.

The switching cell K is for example a MOSFET, IGBT, bipolar or GTO component controlled by a circuit not shown.

The filter circuits 5, 7 are for example all-pass filters, which keep the voltage gain constant, and introduce a phase shift as a function of the frequency of the input voltage.

The first filter circuit 5 and the second filter circuit 7 are for example mounted in cascade. They respectively comprise several inductors L1, L2, L3, L4 and several capacitors C1, C2, C3, C4, and are preferably "LC" circuits, that is to say they do not include other components as inductors and capacitors.

Advantageously, the first filter circuit 5 and the second filter circuit 7 are structurally similar to each other.

The first filter circuit 5 has a first input E6 connected to the first output E3 of the switching circuit 3, and a second input E7 connected, preferably directly, to the negative terminal BB ₁ of the voltage source S ₁ . The first filter circuit also has a first output E8 and a second output E9 respectively connected, preferably directly, to a first input E10 and a second input E11 of the second filter circuit 7 (cascade connection).

The second filter circuit 7 comprises a first output E12 connected, preferably directly, to the first output CC1 of the module CV1, and a second output E13 connected, preferably directly, to the second output E4 of the switching circuit 3.

The first output E9 of the first filter circuit 5 and the first input E11 of the second filter circuit 7 are directly connected, preferably directly, to the second output DD1 of the module CV1.

The first filter circuit 5 comprises for example a first branch 9 directly connecting its first input E6 to its first output E8 and comprising the inductance L1. The first filter circuit also includes, for example, a second branch 11 directly connecting its second input E7 to its second output E9 and including inductance L2.

The first filter circuit 5 comprises for example a third branch 13 directly connecting its first input E6 to its second output E9 and comprising the capacitor C2, and for example a fourth branch 15 directly connecting its second input E7 to its first output E8 and comprising capacitor C1.

In the example represented, the filter circuits 5, 7 are said to be in “X”, because of their third branches and fourth branches which intersect.

The inductors L1 and L2 advantageously have the same value (in mH), as do the capacitors C1 and C2 (in μF).

Similarly, the second filter circuit 7 comprises a first branch 17, a second branch 19, a third branch 21 and a fourth branch 23 similar to those of the first filter circuit 5 and respectively comprising the inductance L3, the inductance L4 , capacitor C4 and capacitor C3.

The inductances L3 and L4 are advantageously of the same value, for example the same as that of the inductances L1, L2.

Capacitors C3 and C4 are advantageously of the same value, for example that of capacitors C1 and C2.

According to variants not shown, one or more additional filter circuits, for example “LC” circuits, are interposed between the filter circuits 5 and 7, or between the outputs CC1, DD1 and the filter circuit 7.

The operation of system 1 will now be described.

The CV1-CVi modules operate similarly to each other, so only the operation of the CV1 module is described below.

The switching cell K is controlled to be cyclically closed for a time Tc, during which it is conductive, and open for a time To, during which it is blocked (non-conductive).

The duty cycle α1 of the control signal is defined by α1=Tc/(Tc+To).

The ratio between the output voltage Us1 and the input voltage Ue1 is a function of the duty cycle α1.

When the ratio of the load resistance Rch divided by the internal resistance RL of the storage inductor L is very large, the relationship between the input and output voltages is of the form Us1/Ue1 = 1/(1- α1).

Thus, by acting on the control of the switching cell K, the desired output voltage Us1 is obtained.

The filter circuits 5, 7 have the effect of stabilizing the output voltage Us1 with respect to a situation where they would be absent. They also have the effect of reducing energy losses as will be seen in an example below.

When the switching cell K is in a closed state, the storage inductance L is in series with the inductors L4 and L2 belonging respectively to the second filter circuit and to the first filter circuit. In other words, the current flows in the CV1 module as shown in Figure 4 from the positive terminal AA1 to the negative terminal BB1 passing successively through the storage inductance L, the switching cell K, the inductance L4 and inductance L2 according to the thick arrows represented in FIG. 4. This charges the storage inductance L and the inductors L2 and L4 with energy.

When the switching cell K is in an open state, the current crosses the entire upper line of the module CV1, that is to say successively the storage inductor L, the diode D, the inductor L1 and the inductor L3 following the finer arrows shown in figure 4. The current returns from the second output DD1 to the negative terminal BB1 passing through the inductance L2 following the fine arrows shown in figure 4.

By controlling the switching cells K of each of the modules CVi, the duty cycles αi of each of the modules CVi are adjusted to adjust the output voltages Usi to predetermined values.

Thus, by varying the duty cycle αi of each of the modules CVi, it is possible to adjust the output voltage Us of system 1. It is thus possible, for example, to fix the value of the output voltage Us.

According to a particular mode of operation, all the duty cycles αi are equal to the same value α controlled to fix the output voltage Us at a predetermined value.

Example 1

In this example, the system 1 according to the invention comprises only the voltage source S1 and the module CV1. The output voltage Us1 supplies the load Rch. The values of the components of the CV1 module are given in the table below.

System 1 is compared to a reference system similar to system 1, but in which module CV1 is replaced by the conventional “boost” chopper circuit represented in FIG. 3. The components of the “boost” chopper circuit have the same values as switching circuit components 3.

Element Name Value Denomination Remark Filter circuits 5, 7 L1, L2, L3, L4 10µH Inductors RL1, RL2, RL3, RL4 1mΩ Internal resistances of inductors C1, C2, C3, C4 33uF Abilities Switching circuit 3 or Classic “boost” chopper circuit L 500µH Storage inductance RL 1 mΩ50 mΩ then 500 mΩ Storage Inductor Internal Resistance Cdc1 1500uF Input capacitor Cdc2 60µF Switching circuit output capacitor “LC” output filter lf 60µH Filter inductance Used at the output of the reference system. RF 1mΩ Internal resistance of the inductor See 47µF Filter capacity Sources of voltage S1 48V Voltage source S2 24V Voltage source S3 12V Voltage source Charged Rch 5Ω Charged

Table 1 – Value of components in l are examples

In FIG. 6, the ratio Rch/RL is 5000, the value of RL being 1 mΩ. Curve C1 shows the evolution of the Us/Ue ratio of system 1 as a function of the duty cycle, while curve C2 shows the Us/Ue ratio of the reference system.

In FIG. 7, the ratio Rch/RL is 100, the value of RL being 50 mΩ. Curve C3 shows the evolution of the Us/Ue ratio of system 1, while curve C4 shows the Us/Ue ratio of the reference system.

In FIG. 8, the ratio Rch/RL is 10, the value of RL being 500 mΩ. Curve C5 shows the evolution of the Us/Ue ratio of system 1, while curve C6 shows the Us/Ue ratio of the reference system.

As can be seen, curves C1, C3 and C5 are respectively close to curves C2, C4 and C6, but are located above. This proves that the system according to the invention indeed has a voltage-raising effect, slightly better than that of the reference system for components of the same values and under comparable operating conditions.

Example 2

In this example, the system 1 according to the invention comprises three voltage sources S1, S2, S3 and three modules CV1, CV2, CV3 analogous to each other and having the same duty cycle. The output voltages Us1, Us2, Us3 are in series and supply the load Rch. The values of the components of the modules are the same as in example 1 and given by the table above.

System 1 is compared to a reference system similar to system 1, but in which the modules CV1, CV2, CV3 are respectively replaced by the “boost” chopper circuit represented in FIG. 3. The components of the “boost” chopper circuits have the same values as the components of switching circuit 3.

However, the output voltages Us1, Us2, Us3 being very unstable in the reference system, an "LC" filter (not shown) has been added at the output of system 1. This filter comprises an inductance Lf mounted between the first output CC1 and the load Rch, and a capacitor Cf mounted in parallel with the load Rch between the first output CC1 and the second output DD3 (of the third "boost" chopper circuit). The whole forms a low pass filter.

In FIG. 9, curve C7 represents the evolution of the energy efficiency, in %, of system 1 as a function of the duty cycle, with an Rch/RL ratio of 100. Curve C8 represents the evolution of the energy efficiency of the system of reference under the same conditions. In both cases, the efficiency is calculated as the power Us.Is supplied as output to the load Rch, divided by the sum of the powers Ue1.Is1 + Ue2.Is2 + Ue3.Is3 supplied as input by the sources S1, S2, S3. Curve C9 represents the difference between curves C7 and C8.

It can be seen that the energy efficiency of system 1 is much better than that of the reference system for non-zero duty cycles. For example, for a duty cycle of 50%, the efficiency is higher by about 17%.

In figure 10, curve C10 shows the evolution of the Us/Ue ratio of system 1, while curve C11 shows the Us/Ue ratio of the reference system. It can be seen that the voltage-raising effect of system 1 is better than that of the reference system.

Example 3

In order to show the stabilizing effect of filter circuits 5 and 7, system 1 of example 1 has been taken (a single voltage source S1, a single module CV1) and compared again with the reference system of the example 1. However, an input voltage Ue1 of 50V was used, and the switching frequency of cell K was lowered from 30 to 3 kHz to accentuate the ripples. The duty cycle is 50%. The Rch/RL ratio is 100.

In FIG. 11, curve C12 shows the evolution of the output voltage Us of system 1 according to the invention as a function of time, with oscillations of amplitude ΔU1. Curve C13 shows the evolution of the output voltage Us of the reference system, with much stronger oscillations of amplitude ΔU2. This demonstrates that the module according to the invention provides a more stable output voltage, all other things being equal.

Thanks to the characteristics described above, in particular the two filter circuits 5, 7, the modules CVi according to the invention make it possible to reduce the instability of the output voltages Usi, and increase the energy efficiency.

With reference to FIG. 5, a module 100 according to a variant of the invention is described. Module 100 is similar to module CV1 shown in FIG. 2. Similar elements bear the same alphanumeric references and will not be described again. Only the differences will be described below.

The module 100 comprises a switching circuit 103 distinct from the switching circuit 3 represented in FIG. . However, in the switching circuit 103, as in the switching circuit 3, the second output E4 is not directly connected to the second input E2. When the two switching cells K1 and K2 are closed, the storage inductance L is in series with the inductors L2 and L4 of the filter circuits 5 and 7.

Circuit 103 comprises two switching cells K1 and K2 and two diodes D1 and D2. This makes it possible to raise or lower the voltage between the first output E3 and the second output E4 according to the duty cycles of these switching cells.

Module 100 operates in a similar way to module CV1 and has the same advantages in terms of stability and energy efficiency.

This also shows the unexpected beneficial effect of the two filter circuits 5, 7 in combination with different types of switching circuits.

According to particular embodiment modules (not shown), the module 100 is associated with modules analogous to itself or to modules analogous to the module CV1 to produce a system analogous to the system 1 represented in FIG. 1, or to its variants mentioned above.

Claims (10)

Power electronic system (1) comprising at least one module (CV1; 100) adapted to be connected to a voltage source (S1) delivering a DC input voltage (Ue1) between a positive terminal (AA1) and a negative terminal (BB1), and to transform the input voltage (Ue1) into a DC output voltage (Us1) between a first output (CC1) and a second output (DD1) of the module (CV1; 100), the module (CV1 ; 100) comprising:
- a switching circuit (3; 103) comprising a first input (E1) and a second input (E2) intended to be connected respectively to the positive terminal (AA1) and to the negative terminal (BB1) of the voltage source ( S1),
characterized in that the module (CV1; 100) further comprises:
- a first filter circuit (5) having a first input (E6) connected to a first output (E3) of the switching circuit (3; 103), and a second input (E7) intended to be connected to the negative terminal ( BB1) of the voltage source (S1), and
- a second filter circuit (7) having a first input (E10) connected to a first output (E8) of the first filter circuit (5), a second input (E11) connected to a second output (E9) of the first circuit filter (5), a first output (E12) connected to the first output (CC1) of the module (CV1; 100), and a second output (E13) connected to the second output (E4) of the switching circuit (3; 103), the second output (E9) of the first filter circuit (5) being further connected to the second output (DD1) of the module (CV1; 100). A system (1) according to claim 1, wherein the first filter circuit (5) and the second filter circuit (7) are structurally analogous to each other. System (1) according to Claim 1 or 2, in which the first filter circuit (5) and/or the second filter circuit (7) comprises respectively several inductances (L1, L2, L3, L4) and several capacitors (C1 , C2, C3, C4), and is preferably an “LC” circuit. A system (1) according to any of claims 1 to 3, wherein each of the first filter circuit (5) and the second filter circuit (7) comprises:
- a first branch (9, 17) directly connecting its first input (E6, E10) to its first output (E8, E12), and
- a second branch (11, 19) directly connecting its second input (E7, E11) to its second output (E9, E13),
each of the first branch (9, 17) and the second branch (11, 19) comprising at least one inductance (L1, L2, L3, L4), preferably of the same value. A system (1) according to any of claims 1 to 4, wherein each of the first filter circuit (5) and the second filter circuit (7) comprises:
- a third branch (13, 21) directly connecting its first input (E6, E10) to its second output (E9, E13), and
- a fourth branch (15, 23) directly connecting its second input (E7, E11) to its first output (E8, E12),
each of the third branch (13, 21) and the fourth branch (15, 23) comprising at least one capacitor (C1, C2, C3, C4), preferably of the same value. System (1) according to any one of claims 1 to 5, in which the switching circuit (3; 103) forms a voltage boost circuit or a voltage boost-buck circuit when the second output (E4) of the voltage circuit switch (3; 103) is connected directly to the negative terminal (BB1) of the voltage source (S1). System (1) according to any one of claims 1 to 6, in which the switching circuit (3; 103) comprises at least one storage inductance (L) and at least one switching cell (K; K1, K2) . System (1) according to claim 7, configured so that when said switching cell (K; K1, K2) is in a closed state, the storage inductance (L1, L2, L3, L4) is in series with a inductance (L2) of the first filter circuit (5), with an inductance (L4) of the second filter circuit (7), and with the voltage source (S1). System (1) according to any one of claims 1 to 8, either:
- further comprising at least one second DC voltage source (S2), the first output (CC1) and the second output (DD1) of the module (CV1; 100) being connected in series or in parallel with the second voltage source ( S2) continues, or
- comprising at least one second module (CV2) structurally analogous to the module (CV1; 100) and intended to be connected at the input to at least one second voltage source (S2) suitable for delivering a second DC input voltage (Ue2) , the second module (CV2) being suitable for transforming the second input voltage (Ue2) into a second DC output voltage (Us2) between a first output (CC2) and second output (DD2) of the second module (CV2), the first output (CC2) and the second output (DD2) of the second module (CV2) being mounted in series or in parallel with the first output (CC1) and the second output (DD1) of the module (CV1; 100). Conversion method implementing a system (1) according to any one of Claims 1 to 8,
- the module (CV1; 100) being connected to the voltage source (S1) delivering the input voltage (Ue1) to transform the input voltage (Ue1) into the output voltage (Us1), or
- the system (1) comprising a plurality of modules (CV1; 100, CV2…) structurally analogous to each other and respectively connected to voltage sources (S1, S2…) delivering input voltages (Ue1, Ue2…), each of the modules (CV1; 100, CV2…) delivering a continuous output voltage (Us1, Us2…), the modules (CV1; 100, CV2…) being connected so that their respective output voltages (Us1, Us2…) are in series or parallel to each other.