HYBRID SWITCH AND CONTROL UNIT

Description

[0001] The present invention relates to the field of switches and safety protection circuits connected in an electrical circuit and capable of generating electric arcs and, more particularly, hybrid switches and their control device allowing the extinction of such an electric arc and the interruption of the electric current in said electrical circuit. Its subject is a hybrid switch and control device.

[0002] Hybrid switches are known to comprise an electromechanical switch and an electronic switch. The electromechanical switch, based on electromechanical switching, comprises at least one electrical contact and provides a low voltage drop across its terminals in the closed state and good galvanic isolation in the open state, but has the disadvantage of generating electric arcs when the electrical contact opens under load. The electronic switch is free from electric arcs but has a much higher voltage drop in the on state and does not provide galvanic isolation in the open state.

[0003] Hybrid switches essentially aim to take advantage of the respective advantages of the two types of switches by compromising on their respective disadvantages.

[0004] The combination of these two switches, namely the electromechanical switch and the electronic switch, forming the hybrid switch, can be made in series or in parallel or in series and / or parallel combinations. The series combination, which can be done with or without arcing when opening under load depending on the synchronization of the opening commands, ensures galvanic isolation in the open state but has a high voltage drop in the on state. The parallel combination, which can be done with or without arcing when opening under load depending on the synchronization of the opening commands, has a low voltage drop in the on state but does not ensure galvanic isolation in the open state.

[0005] The electronic switch is controlled by an electronic control device and consists of an analog electronic circuit comprising a varistor in parallel with a power semiconductor such as a power transistor, usually a field effect transistor or an insulated gate transistor. The varistor and the semiconductor are connected in parallel directly across the contact terminals of the electromechanical switch.

[0006] The electronic switch generally comprises two parallel branches, namely a first branch comprising the varistor and a second branch comprising the semiconductor. The branch of the electrical circuit of the hybrid switch comprising the electrical contact is parallel to said first and second branches of the electronic switch.

[0007] In operation, we can distinguish, among the known sequences, the time sequence of extinction of the electric arc and interruption of the electric current in several phases, and more particularly according to the following three successive phases: in a first phase, when the contact of the electromechanical switch opens, for example following the detection of an electrical fault, an electric arc appears, in a second phase the semiconductor of the electronic switch is controlled to be switched to the saturated ON state and the electric current then switches completely in the second branch of the electronic switch causing the extinction of the electric arc, then, in a third phase, the semiconductor is controlled to be switched to the blocked OFF state, the sudden interruption of current in the semiconductor generating an overvoltage which activates the varistor having the effect that the electric current then switches completely in the first branch of the electronic switch. The voltage which is established at the terminals of the varistor is sufficient to limit the electric current and achieve the extinction of the electric current.

[0008] However, regardless of the sequence used, the control of the electronic switch, in particular of the power semiconductor, uses complex and digital electronics based on a microprocessor or microcontroller requiring an external stable power supply. Document US 2019 / 0252143 discloses such control / piloting electronics comprising an electronic control unit based on a microcontroller or microprocessor.

[0009] It is also known, in an AC application, or in an application with a bidirectional DC supply, for example in a battery charging or producing an electric current, to incorporate a diode bridge between the varistor and the semiconductor in order to interrupt the current in both directions.

[0010] Document EP3407368A1 relates to an apparatus for controlling an electrical arc extinguishing device in which an electrical device (TR1) requiring control is connected in parallel to a mechanical switch (K1). It comprises a first voltage detection switch (A1) connected to two ends of said electrical device (TR1) and in series in a control loop of the electrical device (TR1). Such a control loop complicates the circuit.

[0011] The present invention aims to overcome these drawbacks by proposing a hybrid switch and control device implementing less complex control electronics that do not require an external power supply.

[0012] For this purpose, the hybrid switch and control device, according to the present invention, allowing the extinction of an electric arc and the interruption of the electric current in an electric circuit, said device comprising, on the one hand, a hybrid switch comprising an electromechanical switch and, in parallel, an electronic switch for assisting in the extinction of the electric arc and the interruption of the electric current resulting from said arc, said electromechanical switch comprising at least one electrical contact capable of being actuated in closing to allow the passage of the electric current in the electric circuit and in opening to interrupt said passage,said electronic switch being configured to be able to extinguish an electric arc occurring when said electrical contact is opened and then interrupt the electric current and consisting of an analog electronic circuit based on a power semiconductor connected to the terminals of the electrical contact and, on the other hand, an electronic control circuit capable of controlling said electronic switch when said electric arc occurs and until the electric current is interrupted, the electronic control circuit consisting of an analog electronic control circuit based on a semiconductor and being configured to detect the appearance of an electric arc occurring at the terminals of the electrical contact and to deliver, to an output of said electronic control circuit, an output signal capable of controlling said electronic switch according to a time sequence of extinction of the electric arc and interruption of the electric current in several phases,is essentially characterized in that the electronic control circuit is configured to detect the appearance of the electric arc: , by its characteristic arc voltage by being able to deliver, depending on the voltage at the terminals of the electrical contact, at the output of said electronic control circuit, an output signal capable of controlling said electronic switch according to the time sequence of extinction of the electric arc and interruption of the electric current in several phases, or by its characteristic emitted light by being able to deliver, depending on said emitted light, at the output of said electronic control circuit, the output signal capable of controlling said electronic switch according to the time sequence of extinction of the electric arc and interruption of the electric current in several phases.

[0013] The invention will be better understood from the following description, which relates to at least one preferred embodiment, given as a non-limiting example, and explained with reference to the appended schematic drawings, in which: [ Fig. 1 ] shows the schematic diagram of the hybrid switch and control device, according to the present invention, connected in an electrical circuit, with the electronic switch and the electronic control circuit in a block diagram form, [ Fig. 2 ] shows the electrical diagram of the hybrid switch and control device, according to the present invention, shown in the figure 1 in a preferred embodiment of the electronic switch, [ Fig. 3 ] shows the electrical diagram of the device, according to the present invention, represented on the figure 2 , with a control transistor of the bipolar transistor type, [ Fig. 4 ] shows the electronic control circuit shown on the figure 3 and freeing itself from capacitors, [ Fig. 5 ] shows the electronic control circuit shown on the figure 3 in a variant with a control transistor of the field effect transistor type, [ Fig. 6 ] shows the electronic control circuit shown on the figure 5 in a variant which does away with capacitors, [ Fig. 7 ] shows the device, according to the present invention, shown in the figures 3, 4 , 5 et 6 , without the electronic control circuit 3 and in an embodiment where the electronic switch is configured to operate in a bidirectional configuration, with a diode bridge, [ Fig. 8 ] shows the device, according to the present invention, shown in the figure2 , the electromechanical switch of which is of the circuit breaker disconnector type and further comprises a second electrical contact equipped with a displacement and arc-breaking breaking chamber and mounted in series with the first electrical contact to the terminals of which the electronic switch is connected.

[0014] The figures show a hybrid switch and control device, according to the present invention, allowing the extinction of an electric arc and the interruption of the electric current in an electric circuit C.

[0015] Such a device, according to the present invention, comprises: on the one hand, a hybrid switch 1, 2 capable of being connected to said electrical circuit C and comprising an electromechanical switch 1 and, in parallel, an electronic switch 2 for assisting in extinguishing an electric arc and interrupting the electric current, said electromechanical switch 1 comprising at least one electrical contact 1a capable of being actuated in closing to allow the passage of electric current in the electrical circuit C and in opening to interrupt said passage.The electronic switch 2 is configured to be able to extinguish an electric arc occurring when said electrical contact 1a is opened and then interrupt the electric current and consisting of an analog electronic circuit based on a power semiconductor Q1 connected to the terminals of the electrical contact 1a and on the other hand, an electronic control circuit 3 capable of controlling said electronic switch 2 when said electric arc occurs and until the electric current is interrupted.

[0016] According to the present invention, the electronic control circuit 3 consists of an analog electronic circuit based on semiconductor Q2. Furthermore, said electronic control circuit 3 is configured to detect the occurrence of an electric arc occurring at the terminals of the electrical contact 1a and to deliver, to an output S of said electronic control circuit 3, an output signal capable of controlling said electronic switch 2 according to a time sequence of extinction of the electric arc and interruption of the electric current in several phases.

[0017] If we refer more particularly to the figures 3, 4 , 5, 6 , 7 et 8 , it can be seen that the electronic control circuit 3 is configured to detect the appearance of the electric arc by its characteristic arc voltage by being able to deliver, as a function of the voltage at the terminals of the electrical contact, to the output S of said electronic control circuit 3, the output signal able to control said electronic switch 2 according to said time sequence of extinction of the electric arc and interruption of the electric current in several phases.

[0018] If we refer to the figures 2 , 3 , 4 , 5 , 6 , 7 et 8 , it can be seen that, in a preferred embodiment of the electronic switch 2, the latter can comprise a parallel association of two branches connected to the terminals of the electrical contact 1a, namely a first branch comprising a varistor RV and a second branch comprising a power transistor Q1, called an electric arc extinguishing assistance transistor Q1, such as an insulated gate bipolar transistor, a field effect transistor ( figures 2 , 3 , 4 , 5 , 6 , 7 et 8 ) or a bipolar transistor. It can also be seen that the output S of the electronic control circuit 3 is connected to the gate or the base of said transistor Q1 for assisting in extinguishing the electric arc so as to be able to apply the output signal to the gate or the base of the transistor Q1 for assisting in extinguishing the electric arc to control said electronic switch 2 by switching, in the saturated ON or blocked OFF state, the transistor Q1 for assisting in extinguishing the electric arc according to several switching phases. The switching phases make it possible to carry out the phases of the time sequence for extinguishing the electric arc and interrupting the electric current.

[0019] As is well known from the operation of transistors, it is recalled that the blocked state OFF corresponds to a state where the transistor is not conducting and the saturated state ON corresponds to a state where the transistor is conducting.

[0020] In operation, the time sequence for extinguishing the electric arc in several phases may comprise three phases, phase 1, phase 2 and phase 3, this starting from an initial phase in which the electrical contact 1a is closed so that the electric current flows in the electrical circuit C, the electronic switch 2 and the electronic control circuit 3 then being inactive while the transistor Q1 for assisting in extinguishing the electric arc is controlled to the blocked OFF state: phase 1: the electrical contact 1a is commanded to open and an electric arc appears at said open electrical contact 1a, phase 2: the output signal of the electronic control circuit 3 applied to the gate or the base of the transistor Q1 for assisting in extinguishing the electric arc has the effect of switching the transistor Q1 for assisting in extinguishing the electric arc from the blocked OFF state to the saturated ON state, the electric current then switching in the second branch of the electronic switch 2 comprising said transistor Q1 for assisting in extinguishing the electric arc and causing the extinction of the electric arc, then phase 3: the output signal of the electronic control circuit 3 applied to the gate or the base of the transistor Q1 for assisting in extinguishing the electric arc has the effect of switching the transistor Q1 for assisting in extinguishing the electric arc from the saturated ON state to the blocked OFF state,which causes an interruption of the current in said transistor Q1 generating an overvoltage activating the varistor RV of the first branch, the electric current then switching into said first branch. The voltage which is established at the terminals of the varistor Rv is sufficient to limit the electric current and achieve the extinction of the electric current.

[0021] At the end of phase 3, the electrical contact 1a is open and the electrical current is zero.

[0022] The hybrid switch and control device, according to the present invention, is therefore adapted, following the appearance of the electric arc due to the opening of the electrical contact 1a, to detect said appearance of electric arc and to carry out a sequence of extinguishing the electric arc and interrupting the electric current by acting on the control voltage of the transistor Q1 for assisting in the extinction of the electric arc, that is to say by piloting / controlling the latter, to switch it from the blocked state OFF to the saturated state ON and vice versa according to several switching phases, for example according to the two aforementioned switching phases.

[0023] If we now refer to the figures 3, 4 , 5 et 6 , it can be seen that the electronic control circuit 3 can comprise, in the first embodiment, a switching transistor Q2, called control transistor Q2, such as a bipolar transistor ( figures 3 et 4 ) or, alternatively, a field effect transistor ( figure 5 et 6 ) and a parallel association of two branches, namely a first branch comprising a first resistor R1 in series with a first capacitor C1 and a second branch comprising a second resistor R2 in series with a second capacitor C2. The control transistor Q2 can be connected, by its collector ( figures 3 et 4 ) or drain ( figure 5 et 6 ), to the first branch at a first junction point forming the output of the electronic control circuit 3 and being located between the first resistor R1 and the first capacitor C1. In addition, the control transistor Q2 can be connected, by its base ( figure 3 ) or grid ( figure 5 ), to the second branch at a second junction point located between the second resistor R2 and the second capacitor C2.

[0024] The phase-by-phase operation of the device, according to the present invention, in this first embodiment of the electronic control circuit 3 can be as follows, from an initial phase where the electrical contact 1a is closed and the electric current flows in the electrical circuit C, the electronic switch 2 and the electronic control circuit 3 being inactive and the first and second capacitors C1 and C2 being discharged: phase 1: the electrical contact 1a is commanded to open and an electric arc appears which is detected by the device, according to the present invention, the voltage across the terminals of the electrical contact 1a being equal to the arc voltage and simultaneously charging the first and second capacitors C1 and C2 via the first and second resistors R1 and R2.When the voltage across the terminals of the first capacitor C1, which forms the output signal of the electronic control circuit 3, exceeds a certain threshold VG(TH), an intrinsic characteristic of the transistor Q1 for assisting with the extinction of the electric arc, the latter is switched to the saturated state ON, which has the effect that the electric current switches from the electric circuit C to the second branch of the electronic switch 2 comprising the transistor Q1 for assisting with the extinction of the electric arc and consequently extinguishes the electric arc, phase 2: the voltage across the terminals of the electrical contact 1a is equal to the drain / source voltage VDS (. figures 3 And 5) or collector / base, intrinsic characteristic voltage of the arc extinguishing assistance transistor Q1 and this voltage continues to charge the second capacitor C2. When the voltage across capacitor C2 exceeds a certain threshold, for example approximately 0.7 V in the case of a silicon transistor, a significant electric current begins to flow in the base ( figure 3 ) or a switching voltage is applied to the gate ( figure 5 ) of the control transistor Q2 which is then switched to the saturated ON state, which has the effect of discharging the first capacitor C1 through said control transistor Q2 and, as soon as the voltage across the terminals of the first capacitor C1 falls below the threshold VG(TH), of switching the transistor Q1 for assisting with electric arc extinction to the blocked OFF state. The sudden interruption of the electric current in the latter generates an overvoltage sufficient to activate the varistor Rv and the electric current then switches completely into the first branch comprising said varistor Rv. phase 3: the electric current flows into the first branch of the electronic switch 2 comprising the varistor RV and the voltage across the terminals of the electrical contact 1a is equal to the limiting voltage of the varistor Rv. The transistor Q1 for assisting with electric arc extinction is maintained in the blocked OFF state because an electric current continues to flow in the base ( figure 3 ) or a switching voltage is always applied to the gate ( figure 5 ) of the control transistor Q2 via the second resistor R2.

[0025] Thus, at the end of the aforementioned sequence, the electric arc is completely extinguished and the electric current completely interrupted despite the appearance of said electric arc.

[0026] Preferably the working voltage of the varistor RV can be chosen so as to cause a rapid drop in the intensity of the electric current until it is switched off.

[0027] Preferably, more particularly in the case where the electric arc extinguishing assistance transistor Q1 is a field effect transistor ( figures 2 , 3 , 4 , 5 , 6 , 7 et 8 ) or an insulated gate bipolar transistor, the choice of said transistor may be such that: VG(TH) (gate voltage) < 50V, preferably less than 10V, at the different values ​​of electric current intensity, this is to ensure that the arc voltage is sufficient to activate the gate of the arc extinguishing assistance transistor Q1, VDS (drain / source voltage) < 50V, preferably less than 10V, at the different values ​​of electric current intensity, because when the arc extinguishing assistance transistor Q1 is switched to the saturated ON state, its impedance must be lower than that of the electric arc to divert the entire electric current.

[0028] The choice of the values ​​of the first resistor R1 and the first capacitor C1 is determined to adjust the time constant t1 of the charge of the first capacitor C1 and therefore the time before the switching of the transistor Q1 for assisting in the extinction of the electric arc, that is to say the time to make it pass from the blocked state OFF to the saturated state ON. Such a time constant t1 can be chosen, for example, preferably, to be less than 100 ms, more preferably between 0 and 5 ms.

[0029] Similarly, the choice of the values ​​of the second resistor R2 and the second capacitor C2 is determined to adjust the time constant t2 of the charge of the second capacitor C2 and therefore the time before the switching of the control transistor Q2, i.e. the time to make it go from the blocked OFF state to the saturated ON state. Such a time constant t2 is preferably chosen to be less than 100 ms, more preferably between 0 and 5 ms

[0030] The value of the first resistor R1 also has an impact on the limitation of the electric current in the control transistor Q2, particularly in phase 3. It should be noted that the arc voltage, intrinsically, decreases when the intensity of the electric current increases. Thus, the more the intensity of the electric current increases, the more the time (duration) of the charge of the first capacitor C1 up to the threshold value VG (TH) of the gate of the transistor Q1 for assisting with the extinction of the electric arc increases. The switching of the transistor Q1 for assisting with the extinction of the electric arc to the saturated state is therefore later when the intensity increases.

[0031] Note that the duration of passage of the electric current in the control transistor Q2 decreases slightly when the intensity of the electric current increases.

[0032] It will also be noted that an interesting property of the electronic control circuit 3 is its self-inhibition beyond a certain intensity threshold. The duration of phase 1 increases when the intensity of the electric current increases and the duration of phase 2 decreases. Indeed, it has been observed that beyond a certain intensity, the voltage across the terminals of the second capacitor C2 exceeds the value of the threshold voltage of the control transistor Q2 (for example a threshold voltage equal to approximately 0.7V) before the voltage of the first capacitor C1 reaches the value of the threshold voltage VG(TH) of the transistor Q1 for assisting with electric arc extinction so that the latter is not switched to the saturated state and the function is then inhibited.

[0033] The time taken to reach or exceed the threshold voltage value depends essentially on the values ​​of the first and second resistors R1, R2 and the first and second capacitors C1 and C2. It is also the result of a compromise between the energy dissipated by the electric arc and that dissipated by the transistor Q1.

[0034] If we now refer to the figures 4 And 6, it can be seen that, compared to the first embodiment of the electronic control circuit 3 comprising resistors R1, R2 and capacitors C1, C2, in a second embodiment of the electronic control circuit 3, the first branch is configured so as to dispense with the first capacitor (C1) and / or the second branch is configured so as to dispense with the second capacitor (C2). Thus, the first branch comprises only the first resistor R1 and / or the second branch comprises only the second resistor R2 and it can be envisaged, according to the present invention, to dispense with only the second capacitor C2 of the second branch and / or only the first capacitor C1 of the first branch.

[0035] It will be understood that, in this second embodiment of the electronic control circuit 3, the values ​​of the time constants t1 and t2 will then be dependent on the values ​​of the resistors R1, R2 and / or the parasitic capacitance of the transistor Q1 for assisting in extinguishing the electric arc (case without the first capacitor C1) and / or the parasitic capacitance of the control transistor Q2 (case without the second capacitor C2).

[0036] In this second embodiment of the electronic control circuit 3 without the capacitors C1 and / or C2, the extinction of the electric arc will then be almost immediate.

[0037] Depending on the type of arc extinguishing assistance transistor Q1 used, i.e. a field effect transistor ( figures 2 , 3 , 4 , 5 , 6 , 7 et 8 ) or an insulated gate bipolar transistor, the electronic control circuit 3 may have the same electrical diagram, only the values ​​of the components (R1, R2, C1, C2) will then be adapted.

[0038] The present invention may also provide, for an alternating electric current, that the electronic control circuit 3 is connected to an electronic switch 2 configured to operate in a bidirectional configuration. figure 7 shows an example of such a configuration in which the electronic switch 2 comprises for this purpose a diode bridge D. The diode bridge D is more particularly connected to the terminals of the varistor Rv.

[0039] The present invention may also provide that the electronic control circuit 3 can be connected to a hybrid switch 1, 2 requiring galvanic isolation and comprising for this purpose an additional electrical contact 1b upstream or downstream of the electrical contact 1a. In this case, the synchronization of the two electrical contacts 1a and 1b has no impact on the operation of the device according to the present invention.

[0040] The self-inhibition function seen previously can be used in an application ( figure 8) where the management of electric currents beyond a certain threshold is taken care of by another device, for example in the case of a circuit breaker of the disconnector type, comprising two electrical contacts 1a and 1b and where one of the two electrical contacts 1b is equipped with an arc displacement and operation breaking chamber known from the state of the art. The breaking chamber manages the extinction of the electric arc for currents whose intensity goes beyond a certain threshold Is and the device according to the present invention, whose hybrid switch 2, 3 is connected in parallel to the other electrical contact 1a, can then manage the extinction of the electric arc occurring at said electrical contact 1a and the interruption of the electric current below said threshold Is.

[0041] The control transistor Q2, such as a bipolar or field effect transistor, can be a PNP or NPN bipolar transistor, a MOSFET (N or P type) or a JFET. It will be understood that depending on the type of transistor used, the electronic control circuit 3 may have the same electrical diagram, only the values ​​of the components (R1, R2, C1, C2) will then be adapted.

[0042] The present invention may also provide, in another embodiment of the first embodiment of the electronic control circuit 3, not shown in the attached figures, that the first capacitor C1 and / or the second capacitor C2 is replaced by an inductance, that is to say an electronic component such as for example a coil or a self-inductor.

[0043] In an alternative, the electronic control circuit 3 is configured to detect the occurrence of the electric arc by its characteristic emitted light by being able to deliver, as a function of said emitted light, to the output S of said electronic control circuit 3, the output signal able to control said electronic switch 2 according to the time sequence of extinction of the electric arc and interruption of the electric current in several phases. In a preferred embodiment, the electronic control circuit 3 may comprise a photosensitive component of the LDR, phototransistor or photodiode type in order to detect the electric arc and to carry out the time sequence of extinction of the electric arc and interruption of the electric current in several phases.

[0044] Thus such an electric arc extinguishing and current interruption sequence or any other sequence of this type using the device according to the present invention makes it possible to detect the appearance of an electric arc, and more particularly the voltage of the electric arc or the light emitted by the latter, at the terminals of the electrical contact 1a and to directly control (or drive) the transistor Q1 for assisting in extinguishing the electric arc of the electronic switch 2, or any other power semiconductor of such an electronic switch 2 performing this function of assisting in extinguishing the electric arc, only from an analog electronic circuit based on a semiconductor (the electronic control circuit 3), that is to say without using complex electronics, in particular based on a microprocessor or microcontroller, as is the case with the known systems of the prior art.

Claims

1. Hybrid switch and control device allowing the extinguishing of an electric arc and the switching off of the electric current in an electrical circuit (C), said device comprising, on the one hand, a hybrid switch (1, 2) comprising an electromechanical switch (1) and, in parallel, an electronic switch (2) for assisting in extinguishing an electric arc and switching off the electric current resulting from said arc, said electromechanical switch (1) comprising at least one electrical contact (1a) able to be closed to allow the flow of the electric current in the electrical circuit (C) and opened in order to switch off said flow, said electronic switch (2) being configured to be able to extinguish an electric arc occurring when said electrical contact (1a) is opened and then switching off the electric current and consisting of a power semiconductor (Q1) based analogue electronic circuit connected across the terminals of the electrical contact (1a) and, on the other hand, an electronic control circuit (3) able to control said electronic switch (2) when said electric arc occurs and until the electric current is switched off, the electronic control circuit (3) consisting of a semiconductor (Q2) based analogue electronic control circuit (3) and being configured to detect the appearance of an electric arc occurring across the terminals of the electrical contact (1a) and to deliver, to an output (S) of said electronic control circuit (3), an output signal able to control said electronic switch (2) according to a temporal sequence for extinguishing the electric arc and for switching off the electric current in several phases, characterized in that said electronic control circuit (3) is configured to detect the appearance of the electric arc: - by its characteristic arc voltage whilst being able to deliver, as a function of the voltage across the terminals of the electrical contact, to the output (S) of said electronic control circuit (3), the output signal able to control said electronic switch (2) according to said temporal sequence for extinguishing the electric arc and for switching off the electric current in several phases, or - by its characteristic emitted light whilst being able to deliver, as a function of said emitted light, to the output (S) of said electronic control circuit (3), the output signal able to control said electronic switch (2) according to the temporal sequence for extinguishing the electric arc and for switching off the electric current in several phases.

2. Device according to Claim 1, characterized in that the electronic switch (2) comprises an association of two branches connected in parallel across the terminals of the electrical contact (1a), namely a first branch comprising a varistor (RV) and a second branch comprising a power transistor (Q1), called a transistor (Q1) for assisting the extinguishing of an electric arc, such as an insulated gate bipolar transistor, a field effect transistor or a bipolar transistor, and in that the output (S) of the electronic control circuit (3) is connected to the gate or to the base of said transistor (Q1) for assisting the extinguishing of an electric arc in such a way as to be able to apply the output signal to the gate or to the base of said transistor (Q1) in order to control said electronic switch (2) by switching, to the saturated state or the off state, the transistor (Q1) for assisting the extinguishing of an electric arc according to several switching phases.

3. Device according to Claim 2, characterized in that the electronic control circuit (3) comprises a switching transistor (Q2), called a control transistor (Q2), such as a bipolar transistor or a field effect transistor and an association of two branches in parallel, namely a first branch comprising a first resistor (R1) in series with a first capacitor (C1) and a second branch comprising a second resistor (R2) in series with a second capacitor (C2) and in that the control transistor (Q2) is connected, on the one hand, by its collector or drain, to the first branch at a first junction point forming the output of the electronic control circuit (3) and being situated between the first resistor (R1) and the first capacitor (C1) and, on the other hand, by its base or gate, to the second branch at a second junction point situated between the second resistor (R2) and the second capacitor (C2).

4. Device according to Claim 3, characterized in that the first branch is configured so as to get rid of the first capacitor (C1) and / or the second branch is configured so as to get rid of the second capacitor (C2).

5. Device according to Claim 1, characterized in that the electronic control circuit (3) comprises a photosensitive component of the LDR, phototransistor or photodiode type in order to detect the electric arc and to carry out the temporal sequence for extinguishing the electric arc and switching off the electric current in several phases.