Electrical power supply module

Abstract

Electrical energy supply module The invention relates to an electrical energy supply module (2) configured to convert alternating electrical energy into direct electrical energy to power a resistive load, comprising a current transformation block (4) comprising a magnetic current transformer (15) having an equivalent magnetizing inductance, a block (6) for converting alternating voltage into direct voltage, an energy storage block (10), and an output voltage regulation block (12) adapted to supply electrical energy to the resistive load (14). The block (6) for converting alternating voltage into direct voltage comprises a compensation capacitor (22) configured to compensate for an energy loss due to the magnetic current transformer, the block (6) for converting alternating voltage into direct voltage being connected between the current transformation block (4) and the energy storage block (10).Figure for abstract: Figure 2.

Description

Title of the invention: Electrical energy supply module

[0001] The present invention relates to an electrical power supply module, configured to convert alternating electrical power into direct electrical power to power a resistive load.

[0002] The invention relates to the field of electrical power supply for loads.

[0003] More particularly, the invention lies in the field of supplying electrical energy by recovering electrical energy from a magnetic field formed around a conductor crossed by an electric current.

[0004] The use of a current transformer and a current rectifier, configured to obtain direct electrical energy from alternating electrical energy (or AC / DC) is known, but such conventional current transformers have a size which is not compatible with certain applications.

[0005] An objective of the invention is to propose an electrical energy supply module, intended to supply electrical voltage / current to an electronic device (e.g. an electronic card) integrated in a device for measuring electrical quantities. Thus, this measuring device is autonomous in terms of electrical power supply.

[0006] In this context, there is a need to provide an electrical power supply module capable of providing a minimum electrical current of a few hundred micro-amperes (pA), at start-up, while respecting dimensional constraints.

[0007] For this purpose, the invention proposes, according to one aspect, an electrical energy supply module configured to convert alternating electrical energy into direct electrical energy to power a resistive load, comprising a current transformation block comprising a magnetic current transformer having an equivalent magnetizing inductance, an alternating voltage to direct voltage conversion block, an energy storage block, and an output voltage regulation block adapted to supply electrical energy to the resistive load. The alternating voltage to direct voltage conversion block comprises a compensation capacitor configured to compensate for an energy loss due to the magnetic current transformer, the alternating voltage to direct voltage conversion block being connected between the current transformation block and the energy storage block.

[0008] Advantageously, the proposed electrical energy supply module is compact, thanks to the compensation capacitor configured to compensate for an energy loss due to the equivalent magnetizing inductance of the magnetic current transformer. Indeed, the compensation capacitor creates a resonant effect with the trans block current formation, which makes it possible to optimize energy collection, and consequently, to reduce the size of the components of the current transformation block to be used for the same electrical energy supplied.

[0009] The electrical energy supply module according to the invention may have one or more of the characteristics below, taken independently or in any acceptable combination.

[0010] The AC voltage to DC voltage conversion block is a voltage multiplier block comprising said compensation capacitor, a first anti-return diode connected to the output of the compensation capacitor, configured to prevent a return of electric current to said compensation capacitor, and a second anti-return diode, connected between a connection point located between the compensation capacitor and the first anti-return diode, and a ground point, the second anti-return diode being configured to prevent a passage of current between said connection point and ground.

[0011] The AC voltage to DC voltage conversion block further comprises a capacitor, connected between the ground point and the output of the first anti-return diode.

[0012] The compensation capacitor has a capacity chosen as a function of an equivalent magnetizing inductance of the magnetic current transformer.

[0013] The capacitance of the condensation capacitor is calculated by the following formula:

[0014] q = —U * o

[0015] in which Cl is the capacitance of the compensation capacitor, L1 the equivalent magnetizing inductance of the magnetic current transformer and co0 the pulsation of the alternating electric current at the output of the current transformation block.

[0016] The energy storage block comprises a storage capacitor, connected between an output point of the conversion block and a ground point.

[0017] The module further comprises an impedance matching block, connected between the AC voltage to DC voltage conversion block and the energy storage block, the impedance matching block performing an equalization between a load impedance and a source impedance, said energy storage block comprising a storage capacitor, connected between an output point of the impedance matching block and a ground point.

[0018] The impedance matching block comprises an inductive component, connected to the output of the voltage conversion block, a diode connected to the output of the inductive component and a transistor, connected between a connection point located between the output of said inductive component and the input of said diode, the transistor being controlled by a control signal depending on a voltage comparison between a voltage of setpoint and an output voltage of the electrical power supply module.

[0019] The voltage conversion block, the impedance matching block, the energy storage block and the voltage regulation block are implemented by an electronic processing unit.

[0020] Other characteristics and advantages of the invention will emerge from the description given below, for information purposes only and in no way limiting, with reference to the appended figures, among which:

[0021] [Fig-1] [Fig.l] is a representation of the main blocks of a module of supply of electrical energy according to one embodiment;

[0022] [Fig.2] [Fig.2] is an example of implementation of the blocks of a module of supply of electrical energy according to a first embodiment;

[0023] [Fig.3] [Fig.3] is an equivalent electrical model of the magnetic transformer current of [Fig.2];

[0024] [Fig.4] [Fig.4] is a curve graph illustrating the supply performance of electrical energy.

[0025] [Fig.l] illustrates the main blocks of an electrical power supply module 2.

[0026] The electrical energy supply module 2 is configured to collect electrical energy from the magnetic field created by an electrical conductor.

[0027] More generally, the module 2 is configured to supply electrical energy from an alternative electrical energy source to transform it into direct electrical energy, and to power a resistive load 14, e.g. an electronic card configured to perform calculations, for example to calculate characteristic values of electrical quantities in an electrical installation. In particular, a direct voltage is supplied at the output of the electrical energy supply module 2 to power the load.

[0028] The electrical energy supply module 2 comprises a current transformation block 4 comprising a current transformer.

[0029] In a known manner, a magnetic current transformer comprises primary and secondary windings (or electrical coils), the electrical currents passing through these windings being respectively called primary current and secondary current. The secondary current is practically proportional to the primary current and phase-shifted from it by an angle close to zero for an appropriate direction of the connections.

[0030] Such a magnetic current transformer is represented by an equivalent electrical model comprising a current source and an inductive component, called the equivalent magnetizing inductive component, connected in parallel with the current source. The inductance of the inductive component is subsequently called the magnetic inductance. equivalent magnetic current transformer.

[0031] At the output of the current transformation block 4 is connected a block 6 for converting alternating electrical energy into direct electrical energy (AC / DC conversion), in particular configured to transform an alternating voltage into direct voltage.

[0032] Hereinafter, block 6 will be called voltage conversion block or AC / DC conversion block.

[0033] Advantageously, this voltage conversion block 6 comprises in particular a capacitive circuit which is configured to compensate for the energy losses of the equivalent magnetizing inductive component of the current transformation block 4.

[0034] In one embodiment, the voltage conversion block 6 is a voltage multiplier, preferably a Greinacher circuit type voltage doubler, and more generally a voltage multiplier, as explained in more detail below with reference to [Fig.2].

[0035] The module 2 further comprises, at the output of the voltage conversion block 6, an impedance matching block 8, the output of which is connected to the input of an electrical energy storage block 10.

[0036] The impedance matching block 8 performs an equalization between a load impedance and a source impedance.

[0037] The impedance matching block 8 is optional, embodiments without such an impedance matching block 8 are conceivable.

[0038] The electrical energy supply module 2 further comprises a voltage regulation block 12, adapted to regulate the DC voltage at the output of the module 2 to the electrical consumption requirements of the load 14.

[0039] An embodiment of electrical circuits making it possible to realize each of the blocks described functionally above is illustrated in [Fig.2].

[0040] In this embodiment, the current transformation block 4 comprises a magnetic current transformer 15 comprising a primary winding 16 and a secondary winding 17.

[0041] [Fig. 3] illustrates an equivalent electrical model of the magnetic current transformer 4, in the form of a current source 18 and an equivalent magnetizing inductive component 20, of equivalent magnetizing inductance denoted LL

[0042] In the embodiment of [Fig.2], the AC / DC conversion block 6 is a Greinacher voltage doubler circuit.

[0043] This AC / DC conversion block 6 comprises a capacitive circuit, in this embodiment a so-called compensation capacitor 22, having a capacitance value Cl, and a first anti-return diode 24 connected to the output of the compensation capacitor 22.

[0044] The first anti-return diode 24 is configured to prevent a return of electric current to the compensation capacitor 22.

[0045] In addition, the AC / DC conversion block 6 comprises a second anti-return diode 25, connected between a connection point 21 and a low potential point 23, for example connected to ground. The connection point 21 forms a connection node, between the output of the capacitor 22 and the input of the first anti-return diode 24, and the output of the second anti-return diode 25.

[0046] The second anti-return diode 25 is configured to prevent a current flow between the connection point 21 and the ground 23.

[0047] Preferably, the compensation capacitor 22 has a capacitance chosen as a function of the inductance L1, equal to the equivalent magnetizing inductance of the magnetic transformer of the current transformation block 4, so as to obtain a resonance and compensate for an energy loss due to the current transformer.

[0048] In one embodiment, the capacitance Cl is calculated as a function of the inductance Ll by the following formula:

[0049] [Math.l] — 1 "1

[0050] Where wo is the pulsation of the alternating electric current at the output of the current transformation block, where m0 = 2 / r / being the frequency of the signal.

[0051] In addition, the AC / DC conversion block 6 further comprises another capacitor 26, connected between the ground 23 and the output of the anti-return diode 24. The capacitor 26 allows reserve energy storage, for the Greinacher circuit but also for the load.

[0052] For example, in one embodiment, capacitor 26 has a capacitance of 1OpF.

[0053] The impedance matching block 8 is a “Boost DC-DC” type converter in this embodiment. This impedance matching block 8 comprises an inductive component 28 connected to the output of the voltage conversion block 6, a diode 30 connected to the output of the inductive component 28 and a transistor 32, connected between connection point 27 located between the output of the inductor 28 and the input of the diode 30, controlled by a control signal 35 as a function of the voltage supplied at the output of the module 2. The transistor 32 has a switch function, the control signal being a function of a voltage comparison between a setpoint voltage and an output voltage of the electrical energy supply module 2.

[0054] Alternatively, the impedance matching block is implemented by other types of converter, for example a “Buck-Boost DC-DC converter”, or a “Buck DC-DC converter” type converter.

[0055] Transistor 32 is for example a MOSFET transistor.

[0056] The energy storage block 10 comprises a storage capacitor 34 connected between the output of the impedance matching block 8 and the ground 23.

[0057] For example, storage capacitor 34 has a capacitance of 330pF.

[0058] The voltage regulation block 12 comprises a linear voltage regulator or a switching regulator.

[0059] Advantageously, the use of a voltage conversion block comprising a compensation capacitor makes it possible to compensate for the losses induced by the magnetizing inductive component of the current transformation block.

[0060] Advantageously, the addition of an impedance matching block makes it possible to optimize the supply of electrical energy by the electrical energy supply module 2, while making it possible to reduce the size of this module 2.

[0061] [Fig.4] illustrates the performance obtained, and more precisely the voltage supplied in output of an electrical energy supply module 2 with respect to an electrical energy supply module respectively lacking an AC voltage to DC voltage conversion block, comprising a capacitive circuit comprising an inductance compensation capacitor or an impedance matching block.

[0062] [Fig.4] represents a graph, the abscissa axis representing time and the ordered the voltage across the storage capacitor 34

[0063] Curve G1 represents the voltage obtained without implementing the resonance of the voltage conversion block 6 including the inductance compensation capacitor 22, and without the impedance matching block 8. A DC voltage of approximately 2V is obtained after the charging time of the storage capacitor 34.

[0064] Curve G2 represents the voltage obtained when the value of the compensation capacitor of module 2 is matched with the value of the equivalent magnetizing inductance of the magnetic current transformer, (or in other words, with resonance), without an impedance matching block; curve G3 represents the voltage obtained when the electrical energy supply module 2 comprises a voltage conversion block 6 with a compensation capacitor for the equivalent magnetizing inductance (in other words, with resonance) and with an impedance matching block 8.

[0065] As illustrated in [Fig.4], with an identical current transformation block 4, the voltage supplied by the electrical energy supply module 2 is much higher when the voltage conversion block 6 with resonance, then the impedance adaptation block 8 are used.

[0066] In the above description, the AC voltage to DC voltage conversion block is implemented by a Greinacher voltage multiplier.

[0067] Alternatively, other types of AC / DC converter comprising a capacitor of inductance compensation can be implemented. Advantageously, the electrical energy supply module described can be integrated into a device for measuring electrical quantities, of the closed or opening type.

[0068] For example, the current transformation block 4 is produced in the form of a sensor comprising a through housing adapted to receive an electrical conductor, of the closed type or of the opening type, and the voltage conversion blocks 6, 8 of impedance adaptation, 10 of energy storage and 12 of voltage regulation are produced by an electronic processing unit, for example in the form of integrated circuits on an electronic card.

Claims

Claims

1. Electrical energy supply module configured to convert alternating electrical energy into direct electrical energy to power a resistive load, comprising a current transformation block (4) comprising a magnetic current transformer having an equivalent magnetizing inductance, a block (6) for converting alternating voltage into direct voltage, said block (6) being a Greinacher voltage multiplier, an energy storage block (10), and an output voltage regulation block (12) adapted to supply electrical energy to the resistive load (14), characterized in that the block (6) for converting alternating voltage into direct voltage comprises a compensation capacitor (22) configured to compensate for an energy loss due to the magnetic current transformer,the block (6) for converting alternating voltage into direct voltage being connected between the current transformation block (4) and the energy storage block (10).,

2. Module according to claim 1, in which the block (6) for converting alternating voltage into direct voltage is a voltage multiplier block comprising said compensation capacitor (22), a first anti-return diode (24) connected to the output of the compensation capacitor (22), configured to prevent a return of electric current to said compensation capacitor (22), and a second anti-return diode (25), connected between a connection point (21) located between the compensation capacitor (22) and the first anti-return diode (24), and a ground point (23), the second anti-return diode (25) being configured to prevent a passage of current between said connection point (21) and ground.

3. Module according to claim 1 or 2, wherein the compensation capacitor (22) has a capacitance chosen as a function of an equivalent magnetizing inductance of the magnetic current transformer.

4. Module according to claim 3, wherein the capacitance of the condensation capacitor is calculated by the following formula: in which Cl is the capacitance of the compensation capacitor, L1 the equivalent magnetizing inductance of the magnetic current transformer and cüo the pulsation of the alternating electric current at the output of the current transformation block.

5. Module according to any one of claims 1 to 4, wherein said energy storage block (10) comprises a storage capacitor (34), connected between an output point of the conversion block and a ground point (23).

6. Module according to any one of claims 1 to 4, further comprising an impedance matching block (8), connected between the AC voltage to DC voltage conversion block (6) and the energy storage block (10), the impedance matching block (8) performing an equalization between a load impedance and a source impedance, said energy storage block (10) comprising a storage capacitor (34), connected between an output point of the impedance matching block (8) and a ground point (23).

7. Module according to claim 6, wherein said impedance matching block (8) comprises an inductive component (28), connected at the output of the voltage conversion block (6), a diode (30) connected at the output of the inductive component (28) and a transistor (32), connected between a connection point (27) located between the output of said inductive component (28) and the input of said diode (30), the transistor (32) being controlled by a control signal depending on a voltage comparison between a set voltage and an output voltage of the electrical energy supply module (2).

8. Module according to any one of claims 6 or 7, in which the voltage conversion block (6), the impedance matching block (8), the energy storage block (10) and the voltage regulation block (12) are produced by an electronic processing unit.

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