Thyristor control equipment

Abstract

Various embodiments of the present disclosure relate to a thyristor control device including a triac and a first diode connected in series between the triac and a first terminal of the device, the first terminal of the device being configured to be connected to a cathode gate of the thyristor. A second terminal of the control device is configured to be connected to an anode of the thyristor. The triac has a gate connected to a third terminal of the device, the third terminal of the device being configured to receive a control signal. The thyristor is a component of one or more of a rectifier bridge circuit, an inrush current limiting circuit, or a solid-state relay circuit.

Description

[0001] Priority claim

[0002] This application claims priority from French patent application No. 2009057, filed on September 7, 2020, the contents of which are incorporated herein by reference in their entirety to the maximum extent permitted by law. Technical Field

[0003] The present disclosure relates generally to electronic devices, and more particularly to an electronic thyristor control device. Background Art

[0004] A thyristor, also known as a silicon-controlled rectifier or SCR, is formed from four semiconductor layers, typically made of silicon, that are alternately N-type doped and P-type doped.

[0005] More specifically, a thyristor comprises a stack of alternating P-type doped layers and N-type doped layers, wherein the first P-type doped layer forms the thyristor anode, the first N-type doped layer forms the thyristor cathode, the second N-type doped layer contacts the first P-type doped layer, and the second P-type doped layer contacts the first N-type doped layer. When the thyristor gate corresponds to the second N-type doped layer, the thyristor is referred to as an anode-gate thyristor. When the thyristor gate corresponds to the second P-type doped layer, the thyristor is referred to as a cathode-gate thyristor.

[0006] Cathode-gated thyristors are used in many electronic devices. For reasons of power efficiency, or in other words, to limit the power consumed by such thyristors, it is necessary that the triggering (i.e. the controlled switching to the on state) of cathode-gated thyristors occurs in their first quadrant. In the first quadrant, the thyristor is switched to the on state by delivering a positive current to its gate, which flows from the gate to the cathode, while the voltage V between the anode and cathode of the thyristor is AK is positive and greater than the thyristor threshold voltage, the voltage V AK The cathode of the thyristor is used as reference.

[0007] Electronic thyristor control devices configured to deliver a control signal or current to the gate of a thyristor are known. Such control devices are configured to receive a first control signal and generate a second control signal that is delivered to the thyristor gate. In other words, these devices are configured to shape the control signal delivered to the thyristor gate. Such control circuits are also referred to as drivers.

[0008] Known devices for controlling thyristors, in particular cathode-gate thyristors, suffer from various disadvantages.

[0009] There is a need to overcome all or some of the disadvantages of known devices for controlling thyristors, in particular cathode-gate thyristors. Summary of the Invention

[0010] Embodiments overcome all or some of the disadvantages of known thyristor controlled devices.

[0011] One embodiment provides a control device comprising: a triac; and a first diode connected in series between the triac and a first terminal of the control device, the first terminal of the control device being configured to be connected to a cathode gate of a thyristor; and the second terminal of the control device being configured to be connected to an anode of the thyristor; the triac having a gate connected to a third terminal of the control device, the third terminal of the control device being configured to receive a control signal.

[0012] According to an embodiment, the first diode has a cathode coupled to the first terminal of the device.

[0013] According to an embodiment, the cathode of the first diode is connected to the first terminal of the control device, the control device further comprising: a fourth terminal configured to be connected to the gate of the cathode-gated SCR; and a second diode, preferably identical to the first diode, connected in series between the triac and the fourth terminal, the cathode of the second diode being connected to the fourth terminal of the control device, and the second terminal of the control device being further configured to be connected to the anode of the further thyristor.

[0014] According to an embodiment, the device further comprises a circuit configured to deliver the control signal to a third terminal of the device, the circuit being connected to the second terminal of the device and configured to be powered with a supply potential (preferably positive) referenced to the second terminal of the control device.

[0015] Another embodiment provides an integrated circuit comprising the control device defined above.

[0016] Another embodiment provides a rectifier bridge, comprising: a first branch and a second branch, connected in parallel between a first internal node of the rectifier bridge and a second internal node of the rectifier bridge, the first internal node being coupled (preferably connected) to a first output node of the rectifier bridge; a resistor and a thyristor, connected in parallel between the second internal node and the second output node of the rectifier bridge, the anode of the thyristor being connected to the second output node; and a control device as defined above, the second terminal of the control device being connected to the second output node, and the first terminal of the device being connected to the cathode gate of the thyristor.

[0017] According to an embodiment, the rectifier bridge further comprises a circuit configured to deliver a control signal to a third terminal of the control device, the circuit being connected to the second output node of the rectifier bridge and being configured to be powered by a power supply potential (preferably positive) referenced to the second output node of the rectifier bridge.

[0018] Another embodiment provides a rectifier bridge, comprising: a control device as defined above, the second terminal of the control device being connected to a first internal node of the rectifier bridge, the first internal node being coupled (preferably connected) to a first output node of the rectifier bridge; a first thyristor comprising a cathode connected to the first input node of the rectifier bridge, an anode connected to the first internal node, and a cathode gate connected to the first terminal of the control device; and a second thyristor comprising a cathode connected to the second input node of the rectifier bridge, an anode connected to the first internal node, and a cathode gate connected to the fourth terminal of the control device.

[0019] According to an embodiment, the rectifier bridge further comprises a circuit configured to deliver a control signal to a third terminal of the control device, the circuit being connected to a first internal node of the rectifier bridge and being configured to be powered by a power supply potential (preferably positive) referenced to the first internal node of the rectifier bridge.

[0020] According to an embodiment, the rectifier bridge further comprises: a diode comprising a cathode connected to a second internal node of the rectifier bridge, the second internal node being coupled (preferably connected) to a second output node of the rectifier bridge, and comprising an anode connected to a first input node of the rectifier bridge; another diode comprising a cathode connected to the second internal node of the rectifier bridge, and comprising an anode connected to the second input node of the rectifier bridge.

[0021] Another embodiment provides an integrated circuit comprising the rectifier bridge defined above.

[0022] Another embodiment provides a solid-state relay, comprising: a first thyristor and a second thyristor, connected in anti-parallel between a first terminal of the solid-state relay and a second terminal of the solid-state relay, the anode of the first thyristor being connected to the first terminal of the solid-state relay; and a control device as defined above, the first terminal of the control device being connected to the cathode gate of the first thyristor, and the second terminal of the control device being connected to the first terminal of the relay.

[0023] According to an embodiment, the solid-state relay further comprises a circuit configured to deliver a control signal to a third terminal of the control device, the circuit being connected to the first terminal of the solid-state relay and configured to be powered with a power supply potential (preferably positive) referenced to the first terminal of the solid-state relay.

[0024] According to an embodiment, the control circuit is further configured to deliver another control signal to the gate of the second thyristor, preferably, the terminal of the control circuit configured to deliver the another control signal is connected to the gate of the second thyristor or coupled to the gate of the second thyristor through a diode.

[0025] Another embodiment provides an integrated circuit comprising the solid-state relay defined above. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above features and advantages and other features and advantages will be described in detail in the following description of specific embodiments given by way of illustration and not limitation, with reference to the accompanying drawings, in which:

[0027] Figure 1 An embodiment of a voltage rectifier bridge including a thyristor control device according to an embodiment is shown in the form of a circuit;

[0028] Figure 2 A further embodiment of a voltage rectifier bridge comprising a thyristor control device according to a further embodiment is shown in the form of a circuit; and

[0029] Figure 3 The circuit is shown as follows: Figure 2 An embodiment of a solid state relay of the control device. DETAILED DESCRIPTION

[0030] In the various drawings, the same features are designated by the same reference numerals. In particular, common structural and / or functional features among the various embodiments may have the same reference numerals and may be arranged with the same structure, dimensions, and material properties.

[0031] For the sake of clarity, only the steps and elements that are useful for understanding the embodiments described herein are illustrated and described in detail. In particular, various current electronic devices including at least one thyristor, and more specifically at least one cathode-gate thyristor, with which the described control circuit embodiments and variants are compatible, are not all described.

[0032] Unless otherwise indicated, when two elements are referred to as being connected together, this means a direct connection without any intermediate elements other than conductors, and when two elements are referred to as being coupled together, this means the two elements may be connected or they may be coupled via one or more other elements.

[0033] In the following disclosure, unless otherwise indicated, when absolute position modifiers (such as terms "front", "back", "top", "bottom", "left", "right", etc.) or relative position modifiers (such as terms "above", "below", "high", "low", etc.) are mentioned, or when directional modifiers (such as "horizontal", "vertical", etc.) are mentioned, reference is made to the orientation shown in the figures.

[0034] Unless otherwise specified, the expressions "about," "approximately," "substantially," and "approximately" mean within 10%, and preferably within 5%.

[0035] Figure 1An embodiment of a voltage rectifier bridge 1 comprising a thyristor control device 2 according to an embodiment is shown in the form of a circuit.

[0036] Rectifier bridge 1 includes two input nodes 100 and 102. Rectifier bridge 1 also includes two output nodes 104 and 106. Bridge 1 also includes two internal nodes 110 and 112 coupled to respective nodes 106 and 104. More specifically, in this example, node 110 and node 112 are directly connected to respective nodes 106 and 104, or in other words, node 110 is the same as node 106, and node 112 is the same as node 104.

[0037] The rectifier bridge 1 includes a cathode-gate thyristor Th1 connected between a node 100 and a node 110. More specifically, an anode of the thyristor Th1 is connected to the node 110, and a cathode of the thyristor Th1 is connected to the node 100.

[0038] The rectifier bridge 1 further includes a cathode-gate thyristor Th2 connected between the node 102 and the node 110. More specifically, the anode of the thyristor Th2 is connected to the node 110, and the cathode of the thyristor Th2 is connected to the node 102.

[0039] Thyristors Th1 and Th2 form a half-bridge of the rectifier bridge 1 , and more specifically, a lower half-bridge of the rectifier bridge 1 .

[0040] In this example, the rectifier bridge 1 further includes a diode D1 and a diode D2 .

[0041] Diode D1 is connected between nodes 100 and 112. More specifically, the anode of diode D1 is connected to node 100, and the cathode of diode D1 is connected to node 112. Therefore, diode D1 is connected in series to thyristor Th1 between node 110 and node 112. Diode D1 and thyristor Th1 belong to the same first branch of rectifier bridge 1, which couples node 110 and node 112 to each other.

[0042] Diode D2 is connected between node 102 and node 112. More specifically, the anode of diode D2 is connected to node 102, and the cathode of diode D2 is connected to node 112. Therefore, diode D2 is connected in series to thyristor Th2 between node 110 and node 112. Diode D2 and thyristor Th2 belong to the same second branch of rectifier bridge 1, which couples node 110 and node 112 to each other.

[0043] Diode D1 and diode D2 form the other half of the rectifier bridge 1 , and more specifically the upper half of the bridge 1 .

[0044] The rectifier bridge 1 is configured to rectify the AC voltage V applied between the input node 100 and the input node 102. AC The rectifier bridge 1 is configured to deliver a rectified voltage V between its output node 104 and output node 106. Rect .

[0045] In practice, the two output nodes 104 and 106 are connected to the two power supply terminals of the electronic device. Then, the node 106 is at a voltage V Rect Reference potential GND for powered electronic devices.

[0046] Preferably, a capacitor C is connected between the node 104 and the node 106 of the rectifier bridge 1. The capacitor C may form part of the rectifier bridge 1 or be external to the rectifier bridge 1.

[0047] Device 2 is a control device for thyristor Th1; that is, it is configured to control thyristor Th1. More specifically, device 2 is configured to receive a control signal and to generate another control signal from the received control signal. The control signal generated by device 2 is provided to the cathode gate of thyristor Th1. In other words, device 2 is a driver for thyristor Th1.

[0048] The device 2 comprises a terminal 202 configured to be connected to the anode of the thyristor Th1, Figure 1 In , terminal 202 is connected to the anode of thyristor Th1. Figure 1 In FIG, the device 2 comprises a terminal 204 configured to be connected to the cathode gate of the thyristor Th1. The device 2 comprises a terminal 206 configured to receive a control signal.

[0049] Between the terminal 204 and the terminal 202 of the device 2 , the device 2 includes a triac Tr and a diode D3 connected in series with the triac Tr.

[0050] Diode D3 is configured to prevent positive current from flowing from terminal 202 to terminal 204 when diode D3 is reverse biased, i.e., when its anode potential is less than its cathode potential. Furthermore, diode D3 is configured to allow positive current to flow from terminal 202 to terminal 204 and prevent positive current from flowing from terminal 204 to terminal 202 when diode D3 is forward biased. In other words, diode D3 has its cathode coupled to terminal 204 and its anode coupled to terminal 202.

[0051] More specifically, in this embodiment, the cathode of diode D3 is connected to terminal 204, and the anode of diode D3 is connected to a first conduction terminal of triac Tr, a second conduction terminal of triac Tr being connected to terminal 202. Furthermore, the gate of triac Tr is connected to terminal 206 of device 2.

[0052] In this embodiment, device 2 is also a control device for thyristor Th2, i.e., it is also configured to control thyristor Th2. More precisely, device 2 is configured to deliver a control signal to the cathode gate of thyristor Th2. Device 2 then generates a control signal from the control signal received at its terminal 206. In other words, device 2 is a driver for thyristor Th2.

[0053] Next, the device 2 comprises an additional terminal 208 configured to be connected to the cathode gate of the thyristor Th2, Figure 1 In the embodiment of the present invention, terminal 208 is connected to the cathode gate of thyristor Th2. Device 2 also includes diode D4, which is preferably identical to diode D3. Diode D4 is configured to prevent positive current from flowing from terminal 202 to terminal 208 when diode D4 is reverse biased. Furthermore, diode D4 is configured to allow positive current to flow from terminal 202 to terminal 208 and prevent positive current from flowing from terminal 208 to terminal 202 when diode D4 is forward biased. In other words, diode D4 has its cathode coupled to terminal 208 and its anode coupled to terminal 202.

[0054] More specifically, in this embodiment, diode D4 is connected in series with triac Tr. Then, the cathode of diode D4 is connected to terminal 208, and the anode of diode D4 is connected to the first conduction terminal of triac Tr.

[0055] exist Figure 1 , terminal 206 of device 2 is connected to terminal 300 of control circuit 3 (block CTRL). For example, circuit 3 is a microcontroller and terminal 300 is an output terminal of the microcontroller. Circuit 3 is configured to deliver a control signal to terminal 206 of device 2.

[0056] Circuit 3 is connected to terminal 202 of device 2, i.e. to the anode of thyristor Th1. In practice, circuit 3 is configured to be powered by a positive supply potential Vcc referenced to the potential of terminal 202. Thus, circuit 3 is connected to a node for applying potential Vcc. As an example, potential Vcc is converted from voltage Vcc by means of a voltage conversion circuit (e.g., a step-down voltage converter or a capacitive voltage converter). RectThe voltage conversion circuit is obtained so that the terminal is coupled to the terminal 202. It should be noted that if the entire bridge is already started, the step-down conversion works, and when Vcc is still not available, if there is another path to the loop neutral line with a resistor (thermistor), then this method is applicable. Otherwise, the external auxiliary power supply is connected directly to the neutral line.

[0057] The circuit 3 may form part of the device 2 or be external to the device 2. More generally, the circuit 3 may form part of the rectifier bridge 1 or be external to the rectifier bridge 1 .

[0058] In operation, when the voltage V AC When the potential of node 100 is greater than the potential of node 102, diodes D1 and D2 are turned on and off respectively. In addition, the voltage V between the anode and cathode of thyristor Th2 is AK2 is positive, and the voltage V between the anode and cathode of the thyristor Th1 AK1 is negative, and then the thyristor Th1 is turned off. When the circuit 3 delivers the control signal to the terminal 206, that is, when the conduction current (positive in this example) is delivered to the gate of the triac Tr, the triac Tr is turned on. As an example, in order to provide the conduction current, the terminal 300 of the circuit 3 provides a positive voltage pulse with reference to the terminal 202, which is converted into a current pulse by a resistor (not shown) coupling the terminal 300 to the terminal 206. The conduction of the triac Tr causes a positive current to flow through the triac Tr, from the terminal 202 to the terminal 204 and the terminal 208. Since the potential of the node 100 is greater than the potential of the node 102, the diode D3 is reverse biased and turned off. The current flowing through the triac Tr then flows through the forward biased diode D4 to the terminal 208. Therefore, the positive current is supplied to the cathode gate of the thyristor Th2, and the thyristor Th2 is switched to the on state.

[0059] When the potential of the node 100 decreases and approaches the potential of the node 102, becoming equal to the potential of the node 102, the thyristor Th2 and the triac Tr switch to the off state due to the fact that the voltage between the node 100 and the node 102 becomes zero.

[0060] To simplify the above description of the operation of bridge 1 and device 2, the threshold voltages of the diodes, thyristors and triacs have been ignored. When these threshold voltages are taken into account, it will be within the ability of those skilled in the art to infer the operation of bridge 1 and device 2.

[0061] Furthermore, it will be within the ability of one skilled in the art to determine the operation of bridge 1 and device 2 in the case where the potential of node 102 is greater than the potential of node 100, which is symmetrical to the operation described above in the case where the potential of node 100 is greater than the potential of node 102. In particular, in the case where the potential of node 102 is greater than the potential of node 100, since the voltage V AK2 The fact that V is negative, the diode D4 is reverse biased and the thyristor Th2 is turned off. Therefore, when the control signal delivered by the circuit 3 is received by the terminal 206 of the device 2 and the triac Tr is switched to the conductive state, the positive current flowing from the terminal 202 through the triac Tr is delivered to the cathode gate of the thyristor Th1, which has a voltage V AK1 The fact that is positive, the thyristor Th1 switches to the on state.

[0062] Diodes D3 and D4 are selected so that they have sufficient breakdown voltage (relative to voltage V AC The amplitude of the voltage swing and / or possible overvoltage between the node 100 and the node 102, such overvoltage caused by, for example, electrostatic discharge between the node 100 and the node 102) is also within the scope of those skilled in the art.

[0063] An advantage of the device 2 is that the switching of the thyristor Th1 and the thyristor Th2 is realized in the first operating quadrant of the thyristor Th1 and the thyristor Th2 , respectively.

[0064] The advantage of device 2 is that when thyristor Th1 or thyristor Th2 is turned off (because its voltage V AK1 or V AK2 is negative, this is due to the fact that the diode D3 or the diode D4 is turned off (reverse biased)), the leakage current flowing through the cathode gate of the thyristor Th1 and the thyristor Th2 is much lower, for example at least 10 times or 100 times lower, than the leakage current that would flow in the absence of the diode D3 and the diode D4 (for example, such leakage current is then about 100 μA).

[0065] The advantage of device 2 is that circuit 3 does not need to know the voltage V AC The polarity of the detection voltage V AC After each zero crossing is detected, the circuit 3 then delivers the control signal to the terminal 206 of the device 2 and only the correct thyristor Th1 or thyristor Th2, i.e. with a positive voltage (V AK1 or V AK2 ) is switched to the on state by switching the thyristor Th1 or thyristor Th2 to the on state.

[0066] An advantage of the device 2 is that the thyristor Th1 and the thyristor Th2 cannot be turned on simultaneously, even if the circuit 3 delivers a single control signal.

[0067] An advantage of the device 2 is that the control circuit 3 delivers a single control signal to control both thyristors Th1 and Th2 , which enables the use of a single output terminal of the circuit 3 , for example a microcontroller.

[0068] An advantage of the device 2 is that it enables the use of a control circuit 3 with a positive power supply Vcc which can be obtained without the use of a charge pump or an optocoupler.

[0069] An advantage of the device 2 is that the positive power supply Vcc of the circuit 3 can be directly referenced to the ground GND node 106 .

[0070] An advantage of the device 2 is that it can be manufactured entirely in the form of an integrated circuit and, more generally, it enables the bridge 1 to be formed entirely in the form of an integrated circuit.

[0071] An advantage of device 2 is that triac Tr can be scaled so that a positive current applied to its gate having a relatively low value, for example less than or equal to about 0.1 A, or even less than 10 mA, is sufficient to turn it on. This enables circuit 3 to be implemented, for example, by a microcontroller, since it is known that the microcontroller can only deliver currents having relatively low values.

[0072] An advantage of device 2 is that the threshold voltages of diodes D3 and D4 and of triac Tr have an effect on the control section of thyristors Th1 and Th2, but have no effect on the power section of thyristors Th1 and Th2. In other words, device 2 makes it possible to avoid the use of threshold components, in addition to threshold components Th1, Th2, D1, and D2, that would be connected in series with thyristor Th1 in the branch of bridge 1 that includes thyristor Th1, or with thyristor Th2 in the branch of bridge 1 that includes thyristor Th2, which would reduce the efficiency of bridge 1.

[0073] The positions of the diodes D1 and D2 can be designed to be reversed with respect to the positions of the thyristors Th1 and Th2. However, in order to deliver a positive conduction current to the gate of one or the other of the thyristors Th1 and Th2 so as to turn on the thyristors in their first quadrants, an isolated power supply, for example, isolated by an isolation transformer or by an optocoupler, should be provided, which delivers a positive potential reference to the node 112 of the bridge 1.

[0074] It is also possible to replace the cathode gate thyristors Th1 and Th2 with anode gate thyristors controlled to conduct in their first quadrant. However, it is not possible to manufacture such anode gate thyristors conducting in the first quadrant in an integrated form, and according to an embodiment, the bridge 1 forms part of an integrated circuit.

[0075] Furthermore, replacing the cathode-gate thyristors Th1 and Th2 with anode-gate thyristors controlled to conduct in their first quadrant would require providing a source of negative potential referenced to the anodes of the anode-gate thyristors, which is undesirable.

[0076] An embodiment of the device 2 has been described which is capable of controlling the two thyristors Th1 and Th2 of the bridge 1. In an alternative embodiment not shown, the device 2 comprises an additional triac in series with an additional diode D4, the gate of the additional triac being connected to the terminal 206 of the device 2.

[0077] Figure 2 A further embodiment of a voltage rectifier bridge 1 ′ comprising a thyristor control device 2 ′ according to a further embodiment is shown in the form of a circuit.

[0078] Here, only the differences between bridge 1 and bridge 1 ′ and between device 2 and device 2 ′ are highlighted.

[0079] Like bridge 1 , bridge 1 ′ includes two branches connected in parallel between node 110 and node 112 .

[0080] However, in this example, in the first branch of bridge 1', thyristor Th1 is replaced by diode D5, which is then connected in series with diode D5. More specifically, the cathode of diode D5 is connected to node 100, and the anode of diode D5 is connected to node 110. Similarly, in the second branch of bridge 1', thyristor Th2 is replaced by diode D6, which is then connected in series with diode D6. More specifically, the cathode of diode D6 is connected to node 102, and the anode of diode D6 is connected to node 110.

[0081] Bridge 1' also differs from bridge 1 in that node 110 is not connected to node 106. In fact, in this embodiment, bridge 1' includes a resistor R connected in parallel with the cathode gate thyristor Th3 between node 110 and node 106. The anode of thyristor Th3 is connected to node 106, and the cathode of thyristor Th3 is connected to node 110.

[0082] Bridge 1' includes a control device 2' for thyristor Th3. Specifically, device 2' is configured to control thyristor Th3. More specifically, device 2' is configured to receive a control signal and generate another control signal from the received control signal. The control signal generated by device 2' is supplied to the cathode gate of thyristor Th3. In other words, device 2' is a driver for thyristor Th3.

[0083] Device 2' and Device 2( Figure 1 ) in that it comprises neither the diode D4 nor the terminal 208. Indeed, in this embodiment, the device 2' controls a single thyristor Th3, unlike the device 2 which controls two thyristors Th1 and Th2.

[0084] Thus, like the device 2, the device 2' comprises a terminal 202 configured to be coupled to the anode of the thyristor Th3, Figure 2 In the embodiment, the terminal 202 is connected to the anode of the thyristor Th3; the terminal 204 is configured to be connected to the cathode gate of the thyristor Th3; and the terminal 206 is configured to receive a control signal.

[0085] Device 2' comprises a triac Tr and a diode D3 connected in series between terminals 204 and 202 of device 2, the gate of triac Tr being connected to terminal 206 of device 2. Diode D3 is configured to ensure the same functionality as in device 2.

[0086] In this example, the cathode of the diode D3 is connected to the terminal 204, and the anode of the diode D3 is connected to the first conduction terminal of the triac Tr, and the second conduction terminal of the triac Tr is connected to the terminal 202. In another example not shown, the anode of the diode D3 is connected to the terminal 202, and the triac Tr is connected between the cathode of the diode D3 and the terminal 204.

[0087] and Figure 1 As in FIG2 , terminal 206 of device 2′ is connected to terminal 300 of circuit 3, which is configured to deliver a control signal to terminal 206 of device 2. Furthermore, circuit 3 is connected to terminal 202 of device 2′, i.e. to the anode of thyristor Th3, and is configured to be powered with a supply potential Vcc referenced to the potential of terminal 202.

[0088] The circuit 3 may form part of the device 2 ′ or be external to the device 2 ′, and more generally the circuit 3 may form part of the rectifier bridge 1 ′ or be external to the rectifier bridge 1 ′.

[0089] The parallel connection of the thyristor Th3 and the resistor R forms a bypass circuit. When the capacitor C is discharged, this circuit makes it possible to limit the inrush current by placing the thyristor Th3 in the off state. Therefore, the capacitor charging is performed with a time constant Rv*Cv, where Rv and Cv represent the resistance and capacitance values ​​of the respective components R and C. Once the capacitor C is sufficiently charged, the thyristor Th3 switches to the on state to avoid possible overheating of the resistor R, which would lead to modifications of the bridge 1' and a reduction in its efficiency. Since the potential of the node 106 is greater than the potential of the node 110, i.e. the voltage V of the thyristor Th3, AK3 The thyristor Th3 switches to the conductive state because the circuit 3 delivers a control signal to the terminal 206 of the device 2', for example, a pulse of a positive potential referenced to the terminal 202. The delivery of the control signal to the terminal 206 causes the triac Tr to conduct and causes the device 2' to deliver a positive current to the cathode gate of the thyristor Th3.

[0090] According to an embodiment, the device 2 ′ or even the entire bridge 1 ′ forms part of an integrated circuit.

[0091] Device 2 ′ has the same advantages as device 2 , except for the advantages associated with controlling two thyristors simultaneously.

[0092] Figure 1 and Figure 2 The embodiments may be combined, ie the rectifier bridge comprises not only the thyristors Th1 and Th2 and their control device 2 , but also a resistor R connected in parallel with the thyristor Th3 controlled by the device 2 ′.

[0093] Furthermore, the bypass circuit and components of the control device 2 ′ may be associated with circuits other than the rectifier bridge in order to limit the inrush current of the capacitor.

[0094] Figure 3 The circuit is shown as follows: Figure 2 An embodiment of the device 2 ′ is a solid-state relay 4 .

[0095] Relay 4 includes two terminals 400 and 402, and includes two cathode-gate thyristors Th4 and Th5 connected in anti-parallel between terminals 400 and 402. In this example, the anode of thyristor Th4 is coupled (preferably connected) to terminal 400, the cathode of thyristor Th4 is coupled (preferably connected) to terminal 402, and symmetrically, the anode of thyristor Th5 is coupled (preferably connected) to terminal 402, and the cathode of thyristor Th4 is coupled (preferably connected) to terminal 400.

[0096] Relay 4 includes about Figure 2The device 2' is described. Terminal 204 is connected to the gate of thyristor Th5, and terminal 202 is connected to the anode of thyristor Th5, i.e. Figure 3 In the example, is connected to terminal 402.

[0097] Relay 4 also includes a circuit 3 whose terminal 300 is connected to terminal 206 to deliver a control signal to device 2'. Furthermore, circuit 3 is connected to terminal 202 of device 2', i.e., to the anode of thyristor Th5, and is configured to be powered by a power supply potential Vcc referenced to the potential of terminal 202. As an example, potential Vcc is provided by a switching power supply that includes electrical isolation between its input and its output, such a power supply being commonly known as a flyback power supply. According to another example, relay 4 is an electronic device that includes a power factor correction (PFC) circuit, and potential Vcc is generated by an additional winding of an inductor of the PFC circuit. In cases where isolation between the control and the line is not required, voltage Vcc can also be referenced to the line, resulting in a simpler solution.

[0098] According to an embodiment, the circuit 3 is further configured to deliver a control signal to the thyristor Th4. The circuit 3 then comprises a terminal 301 coupled (preferably connected) to the cathode gate of the thyristor Th4.

[0099] In an embodiment, terminal 301 may be coupled to the gate of thyristor Th4 via a diode (optional), the diode being configured such that: when the diode is reverse biased, ie when the voltage V AK4 When V is negative, positive current does not flow from terminal 301 to the gate of the thyristor. The diode then connects its anode to terminal 301 of circuit 3. AK4 This diode enables limiting the current leakage via the gate of thyristor Th4 when φ is negative. In the case where the nodes 300 and 301 are connected together, a diode will be necessary.

[0100] The circuit 3 may form part of the device 2 ′ or be external to the device 2 ′, and more generally the circuit 3 may form part of the relay 4 or may be external to the rectifier 4 .

[0101] According to an embodiment, the relay 4 forms part of an integrated circuit.

[0102] The relay 4 operates as follows. When the potential of the terminal 402 is greater than the potential of the terminal 400, the voltage V AK5 is positive, and the voltage V AK4is negative, and the thyristor Th4 is turned off. If the circuit 3 delivers the control signal to the terminal 206 of the device 2', the triac Tr is turned on, and a positive current is delivered to the gate of the thyristor Th5, and the thyristor Th5 is turned on. When the potential of the terminal 402 is less than the potential of the terminal 400, the voltage V AK4 is positive, and the voltage V AK5 If the control signal is negative, the thyristor Th5 is turned off. If the circuit 3 delivers the control signal to the gate of the thyristor Th4, the thyristor Th4 is turned on.

[0103] Although the device 2' is used to control the thyristor Th5 of the relay 4, rather than the thyristors of the voltage rectifier bridge (such as, for example, Figure 2 The thyristor Th3 of the bypass circuit is described, but it has the same advantages as those of device 2.

[0104] Various embodiments and variations have been described. Those skilled in the art will appreciate that certain features of these various embodiments and variations may be combined, and that other variations will occur to those skilled in the art. In particular, it would be within the ability of those skilled in the art to replace diodes D1 and D2 of bridge 1 with other threshold elements, such as transistors, thyristors, or triacs. In particular, it would be within the ability of those skilled in the art to replace diodes D1 and D2 of bridge 1 ′ with other threshold elements, such as transistors, thyristors, or triacs.

[0105] Furthermore, the use of the device 2 or the device 2 ′ for controlling a thyristor is not limited to the case where the thyristor belongs to the lower half of a voltage rectifier bridge, to a bypass circuit of a voltage rectifier bridge or to a solid-state relay.

[0106] Finally, based on the functional indications given above, the practical implementation of the described embodiments and variants is within the capabilities of a person skilled in the art. In particular, the selection of diodes D3 and D4 and / or triac Tr, in particular according to their threshold voltages and / or according to their breakdown voltages, is within the capabilities of a person skilled in the art.

Claims

1. A control device for controlling a thyristor, comprising: triac; as well as a first diode connected in series between the triac and a first terminal of the control device, the first terminal of the control device being configured to be connected to a cathode gate of the thyristor; and wherein the second terminal of the control device is configured to be connected to an anode of the thyristor; Wherein the triac has a gate connected to a third terminal of the control device, the third terminal of the control device being configured to receive a control signal. 2 . The control device of claim 1 , wherein the first diode has a cathode coupled to the first terminal of the control device.

3. The control device according to claim 2, further configured to control another thyristor, the control device further comprising: a fourth terminal configured to be connected to a cathode gate of the another thyristor; as well as a second diode connected in series between the triac and the fourth terminal; wherein the cathode of the second diode is connected to the fourth terminal of the control device; and Wherein the second terminal of the control device is further configured to be connected to an anode of the further thyristor.

4. The control device according to claim 1 further includes a circuit configured to deliver the control signal to the third terminal of the control device, the circuit being connected to the second terminal of the control device and configured to be powered using a power supply potential referenced to the second terminal of the control device.

5. An integrated circuit comprising the control device according to claim 1.

6. A rectifier bridge comprising: A first branch and a second branch are connected in parallel between a first internal node and a second internal node of the rectifier bridge, wherein the first internal node is coupled to a first output node of the rectifier bridge; a resistor and a thyristor connected in parallel with each other between the second internal node and the second output node of the rectifier bridge; wherein the anode of the thyristor is connected to the second output node; as well as Control equipment, including: triac; and a first diode connected in series between the triac and a first terminal of the control device, the first terminal of the control device being configured to be connected to a cathode gate of the thyristor; and wherein the second terminal of the control device is configured to be connected to an anode of the thyristor; wherein the triac has a gate connected to a third terminal of the control device, the third terminal of the control device being configured to receive a control signal; and wherein the second terminal of the control device is connected to the second output node.

7. The rectifier bridge according to claim 6 further includes a circuit configured to deliver a control signal to the third terminal of the device, the circuit being connected to the second output node of the rectifier bridge and configured to be powered by a power supply potential referenced to the second output node of the rectifier bridge.

8. The rectifier bridge of claim 6, wherein the first diode has a cathode coupled to the first terminal of the control device.

9. An integrated circuit comprising the rectifier bridge according to claim 6.

10. A rectifier bridge comprising: The first branch and the second branch are connected in parallel between a first internal node of the rectifier bridge and a second internal node of the rectifier bridge; The first branch includes a first thyristor, and the first thyristor includes a cathode connected to the first input node of the rectifier bridge and an anode connected to the first internal node; wherein the second branch comprises a second thyristor, the second thyristor comprising a cathode connected to the second input node of the rectifier bridge and an anode connected to the first internal node; Control equipment, including: triac; and a first diode connected in series between the triac and a first terminal of the control device, the first terminal of the control device being configured to be connected to a cathode gate of the first thyristor; wherein the second terminal of the control device is configured to be connected to an anode of the first thyristor and an anode of the second thyristor, and to the first internal node; wherein the triac has a gate connected to a third terminal of the control device, the third terminal of the control device being configured to receive a control signal; and A second diode is connected in series between the triac and a fourth terminal of the control device, the fourth terminal of the control device being configured to be connected to a cathode gate of the second thyristor.

11. The rectifier bridge according to claim 10, further comprising a circuit configured to deliver a control signal to the third terminal of the control device, the circuit being connected to the first internal node of the rectifier bridge and configured to be powered using a power supply potential referenced to the first internal node of the rectifier bridge.

12. The rectifier bridge according to claim 10: wherein the first branch further comprises a diode having a cathode connected to the second internal node and an anode connected to the first input node of the rectifier bridge; and The second branch further includes another diode having a cathode connected to the second internal node and an anode connected to the second input node of the rectifier bridge.

13. An integrated circuit comprising the rectifier bridge according to claim 10.

14. A solid-state relay comprising: A first thyristor and a second thyristor are connected in anti-parallel between the first relay terminal and the second relay terminal; wherein an anode of the first thyristor is connected to the first relay terminal; as well as Control equipment, including: triac; and a first diode connected in series between the triac and a first terminal of the control device, the first terminal of the control device being configured to be connected to a cathode gate of the first thyristor; and wherein the second terminal of the control device is configured to be connected to an anode of the first thyristor and the first relay terminal; Wherein the triac has a gate connected to a third terminal of the control device, the third terminal of the control device being configured to receive a control signal.

15. The relay of claim 14, further comprising a circuit configured to deliver a control signal to the third terminal of the control device, the circuit being connected to the first relay terminal and configured to be powered with a power supply potential referenced to the first relay terminal. 16 . The relay of claim 15 , wherein the circuit is further configured to deliver another control signal to the gate of the second thyristor. 17 . The relay according to claim 16 , wherein the another control signal is directly applied to the gate of the second thyristor.

18. The relay of claim 16, wherein the other control signal is coupled to the gate of the second thyristor through a diode.

19. An integrated circuit comprising the solid-state relay according to claim 14.

Images