CN218648571U

CN218648571U - Switching device and power supply equipment

Info

Publication number: CN218648571U
Application number: CN202222361360.7U
Authority: CN
Inventors: 王庆欢; 王德臣; 张秀锋; 赵福高
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2022-09-05
Filing date: 2022-09-05
Publication date: 2023-03-17
Anticipated expiration: 2032-09-05

Abstract

The application provides a switching device and power equipment, wherein the switching device is arranged between a power supply lightning protection unit and a load, in the switching device, the switching unit is connected with an inductance unit in series, one end of the switching unit after being connected with the inductance unit in series is connected with a first end of the power supply lightning protection unit, and the other end of the switching unit after being connected with the inductance unit in series is connected with a first end of the load; the first clamping unit is connected in parallel at two ends of the switch unit; the second clamping unit is connected with the discharge unit in series, one end of the second clamping unit, which is connected with the discharge unit in series, is connected with the first end of the power supply lightning protection unit, and the other end of the second clamping unit, which is connected with the discharge unit in series, is connected with the first end of the load; and the second end of the power supply lightning protection unit is connected with the second end of the load. By implementing the lightning protection device, the lightning protection can be performed on the switch unit, the discharging unit can be automatically turned off after the lightning protection is finished, the safety is good, and the reliability is high.

Description

Switching device and power supply equipment

Technical Field

The application relates to the technical field of power electronics, in particular to a switching device and power supply equipment.

Background

Switches are common devices in electrical engineering, and currently used switches include mechanical switches and solid state switches. Solid state switches have poor inrush current tolerance and miniaturized mechanical switches also have the problem of insufficient mechanical contact inrush current tolerance. In the process of lightning stroke, the current and the voltage passing through the switch are increased instantly, the switch is easy to be permanently damaged, and even the safety problem is caused. Therefore, how to protect the switch from lightning is a problem of intensive research.

SUMMERY OF THE UTILITY MODEL

The application provides a switching device and power supply equipment, can carry out lightning protection to the switch element, and the discharge unit can turn off automatically after the lightning protection, and the security is good, and the reliability is high.

In a first aspect, an embodiment of the present application provides a switching device, where the switching device is disposed between a power lightning protection unit and a load, and the switching device includes a switching unit, two clamping units, an inductance unit, and a discharge unit; wherein the two clamping units include a first clamping unit and a second clamping unit.

The specific connection relationship of the switching device is as follows: the switch unit is connected with the inductance unit in series, one end of the switch unit connected with the inductance unit in series is connected with the first end of the power supply lightning protection unit, and the other end of the switch unit connected with the inductance unit in series is connected with the first end of the load. The first clamping unit is connected in parallel at two ends of the switch unit. The second clamping unit is connected with the discharge unit in series, one end of the second clamping unit, which is connected with the discharge unit in series, is connected with the first end of the power supply lightning protection unit, and the other end of the second clamping unit, which is connected with the discharge unit in series, is connected with the first end of the load; and the second end of the power supply lightning protection unit is connected with the second end of the load.

In the embodiment of the application, the first clamping unit can protect the switch unit; the second clamping unit can improve the turn-off voltage of the discharge unit, namely the second clamping unit can prevent the discharge unit from being automatically turned off when the switch unit is in a turn-off state, so that the discharge unit is always turned on, a load is always communicated with a power supply through a branch where the discharge unit and the second clamping unit are connected in series, and the load is always in a power-on state. Therefore, the embodiment of the application can carry out lightning protection on the switch unit, and the discharge unit can be automatically turned off after the lightning protection is finished, so that the safety is good, and the reliability is high.

With reference to the first aspect, in a first possible implementation manner, any one of the two clamping units includes at least one of a transient suppression diode and a varistor. It should be explained that the response speed of the transient suppression diode is fast; the piezoresistor has strong current capacity and low cost, and at least one of the transient suppression diode and the piezoresistor is selected and used according to requirements in specific production practice.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner, the discharge unit includes a gas discharge tube or a semiconductor discharge tube. It will be appreciated that the voltage required for the conducting action of a semiconductor discharge tube relative to a gas discharge tube is less than the voltage required for the conducting action of a gas discharge tube.

In a second aspect, an embodiment of the present application provides a switching device, where the switching device is disposed between a power lightning protection unit and a load, and the switching device includes a switching unit, a clamping unit, an inductance unit, and a discharging unit.

The specific connection relationship of the switching device is as follows: the switch unit is connected with the inductance unit in series, one end of the switch unit connected with the inductance unit in series is connected with the first end of the power supply lightning protection unit and one end of the discharge unit, and the other end of the switch unit connected with the inductance unit in series is connected with the first end of the load and the other end of the discharge unit. The clamping unit is connected in parallel at two ends of the switch unit, and the second end of the power supply lightning protection unit is connected at the second end of the load.

With reference to the second aspect, in a first possible implementation manner, the discharge unit includes a gas discharge tube, and the switching unit may switch from the off state to the on state when a current of the gas discharge tube is greater than a preset first current threshold, where a voltage across the gas discharge tube is smaller than a voltage required for maintaining the gas discharge tube on, and the gas discharge tube is turned off. According to the embodiment of the application, the second clamping unit is omitted, and the gas discharge tube can be turned off by adopting the conducting switch unit.

With reference to the second aspect, in a second possible implementation manner, the discharge unit includes a semiconductor discharge tube, and the switching unit may switch from the off state to the on state when a current of the semiconductor discharge tube is greater than a second preset current threshold, where a voltage across the semiconductor discharge tube is smaller than a voltage required for maintaining the semiconductor discharge tube in an on state, and the semiconductor discharge tube is turned off. According to the embodiment of the application, the second clamping unit is omitted, and the semiconductor discharge tube can be turned off by turning on the switch unit.

With reference to the second aspect, in a third possible implementation manner, the discharge unit includes one N-layer gas discharge tube, where N is greater than or equal to 2. This application embodiment is integrated into a stromatolite gas discharge tube with N gas discharge tube, can avoid gas discharge tube can't turn-off automatically after the thunderbolt is ended, need not further to switch on the switch unit and comes the gas discharge tube to turn off.

With reference to the third possible implementation manner of the second aspect, in a fourth possible implementation manner, the discharge unit further includes N-1 capacitor units, and the N-layer gas discharge tube includes an input end, an output end, and N-1 capacitor ends. One of the N-1 capacitor units is connected between the first end of the N layers of gas discharge tubes and one of the N-1 capacitor ends; the first end of the N layers of gas discharge tubes is the input end or the output end of the N layers of gas discharge tubes. According to the embodiment of the application, the capacitance unit is added, so that the conduction speed of the N layers of gas discharge tubes is increased, and the voltage required by the conduction action of the N layers of gas discharge tubes is reduced.

With reference to the second aspect, in a fifth possible implementation manner, the discharge unit includes M gas discharge tubes connected in series; wherein M is greater than or equal to 2. This application embodiment can avoid gas discharge tube can't automatic shutoff after the thunderbolt is ended through the quantity that increases gas discharge tube, need not further to switch on the switch unit and comes the gas discharge tube to turn off.

With reference to the fifth possible implementation manner of the second aspect, in a sixth possible implementation manner, the discharge unit further includes M-1 capacitor units, where one capacitor unit of the M-1 capacitor units is connected between a common node and an intermediate node, and the common node is any end of the M gas discharge tubes after being connected in series; the middle node is a series connection point of any two gas discharge tubes in the M gas discharge tubes. The embodiment of the application accelerates the conduction speed of the gas discharge tube by increasing the capacitance unit, and reduces the voltage required by the conduction action of the gas discharge tube.

In a third aspect, an embodiment of the present application provides a power supply apparatus, where the power supply apparatus includes a power supply lightning protection unit and at least one switching device in the first aspect or any one of the foregoing possible implementation manners in combination with the first aspect. The power supply lightning protection unit can receive the current of the discharge unit in the switch device.

In a fourth aspect, an embodiment of the present application provides a power supply apparatus, which includes a power supply lightning protection unit and at least one switching device in the second aspect or any one of the foregoing possible implementations in combination with the second aspect. The power supply lightning protection unit can receive the current of the discharge unit in the switch device.

It should be understood that the implementations and advantages of the various aspects described above in this application are mutually referenced.

Drawings

Fig. 1 is a block diagram of a power supply device according to an embodiment of the present disclosure;

fig. 2 is a block diagram of another structure of a power supply device according to an embodiment of the present disclosure;

fig. 3 is a block diagram of a switching device according to an embodiment of the present disclosure;

FIG. 4 is a circuit diagram of a switching device according to an embodiment of the present disclosure;

FIG. 5 is a further circuit diagram of a switching device according to an embodiment of the present application;

fig. 6 is a further circuit diagram of a switching device according to an embodiment of the present application;

fig. 7 is a block diagram of another structure of a switching device according to an embodiment of the present disclosure;

fig. 8 is a further circuit diagram of a switching device according to an embodiment of the present application;

fig. 9 is a further circuit diagram of a switching device according to an embodiment of the present application;

fig. 10 is a further circuit diagram of a switching device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The following describes embodiments of the present application in further detail with reference to the accompanying drawings.

Referring to fig. 1, fig. 1 is a block diagram of a power supply device according to an embodiment of the present disclosure. As shown in fig. 1, the power supply 10 includes a power lightning protection unit 101, the power lightning protection unit 101 is connected to one end of a switch device 102, and the other end of the switch device 102 is connected to the load 11, that is, the switch device 102 is disposed between the power lightning protection unit 101 and the load 11.

The power lightning protection unit 101 may discharge a momentary large current to the ground, thereby securing the safety of the switching device 102 and the load 11. The types of the power lightning protection unit 101 include, for example, a protection gap, a valve-type lightning protection device, a zinc oxide lightning protection device, and the like, and the specific type of the power lightning protection unit is not limited in this embodiment of the application.

Alternatively, in some possible embodiments, the power supply 10 may be particularly applicable in a base station, referred to as a base station power supply. The load 11 may then be one or more communication devices in the base station. Alternatively, the power supply 10 may be employed in a display screen, traffic light, etc. scenario. The embodiment of the application does not limit the application scene of the power supply.

The switching device 102 includes a switching unit, and the switching unit may be implemented as a solid-state switch such as an Insulated Gate Bipolar Transistor (IGBT), a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), or a Gate Turn-Off Thyristor (GTO). Alternatively, the switching unit may also be embodied as a miniaturized mechanical switch, such as a circuit breaker, a micro circuit breaker, a relay, or an air switch, etc.

Optionally, in some possible implementations, referring to fig. 2, fig. 2 is a block diagram of another structure of the power supply device provided in the embodiment of the present application. As shown in fig. 2, the power supply 20 includes a power lightning protection unit 201 and a switching device 202, and the switching device 202 is disposed between the power lightning protection unit 201 and the load 21. It can be seen that, unlike the power supply 10 shown in fig. 1, the power supply 20 provided in the embodiment of the present application has a power lightning protection unit 201 and a switching device 202 integrated therein, and the integration level is high.

The following describes a specific structure of a switching device provided in an embodiment of the present application with reference to the drawings.

In some possible embodiments, referring to fig. 3, fig. 3 is a block diagram of a switch device provided in an embodiment of the present application. As shown in fig. 3, the switching device 302 is disposed between the power lightning protection unit 301 and the load 31. The switching device 302 includes a switching unit 3020, a first clamping unit 3021, a second clamping unit 3022, an inductance unit 3023, and a discharge unit 3024.

The switch unit 3020 is connected in series with the inductor unit 3023, one end of the switch unit 3020 connected in series with the inductor unit 3023 is connected to the first end of the power lightning protection unit 301, the other end of the switch unit 3020 connected in series with the inductor unit 3023 is connected to the first end of the load 31, and the second end of the load 31 is connected to the second end of the power lightning protection unit 301.

For example, the first terminal of the power lightning protection unit 301 may be a positive terminal, and the first terminal of the load 31 is also a positive terminal, where the switch unit 3020 and the inductance unit 3023 are connected in series to a positive bus between the power lightning protection unit 301 and the load 31. Alternatively, the first end of the power lightning protection unit 301 may be a negative end, and the first end of the load 31 is also a negative end, in which case the switch unit 3020 and the inductor unit 3023 are connected in series to a negative bus between the power lightning protection unit 301 and the load 31. Whether the switching unit 3020 and the inductance unit 3023 are connected in series on the positive bus or the negative bus, the switching unit may control the connection between the power lightning protection unit 301 and the load 31 to be turned on or off.

The inductance unit 3023 may limit the current of the switching unit 3020 or limit the current of the first clamping unit 3021 during the transient variation of the voltage across the switching unit 3020. The inductance unit 3023 includes one or more inductors, and the inductors may be connected in series or in parallel, that is, the number of inductors in the inductance unit and the connection manner of the inductors are not limited in this embodiment of the application.

The first clamping unit 3021 is connected in parallel to both ends of the switching unit 3020. The first clamping unit 3021 includes at least one of a transient suppression diode and a varistor. In a specific implementation, when a lightning strike occurs while the switching unit 3020 is in an off state, i.e., when the voltage across the switching unit 3020 is greater than the breakdown voltage of the transient suppression diode, the transient suppression diode may be turned on, clamping the voltage across the switching unit 3020 to the clamping voltage of the transient suppression diode. Similarly, the voltage dependent resistor may clamp the voltage across the switching unit 3020 to a fixed voltage value when a lightning strike occurs, i.e. when the voltage across the switching unit 3020 is greater than the critical voltage of the voltage dependent resistor, with the switching unit in the off-state. It is understood that the clamping voltage of the transient suppression diode and the voltage value fixed by the voltage dependent resistor clamp are smaller than the withstand voltage of the switching unit 3020. I.e., the transient suppression diode and the varistor, may protect the switching unit 3020 when the switching unit 3020 is in an off state.

The second clamping unit 3022 is connected in series with the discharge unit 3024, one end of the second clamping unit 3022 connected in series with the discharge unit 3024 is also connected to the first end of the power source lightning protection unit 301, and the other end of the second clamping unit 3022 connected in series with the discharge unit 3024 is connected to the first end of the load 31. It can be seen that the branch where the second clamping unit 3022 and the discharging unit 3024 are connected in series is connected in parallel at both ends of the branch where the switching unit 3020 and the inductance unit 3023 are connected in series.

At this time, the second clamping unit 3022 and the discharging unit 3024 may bleed a lightning current into the power lightning protection unit 301, so as to implement lightning protection of the switching unit 3020. In a specific implementation, when a lightning strike occurs, no matter the switching unit 3020 is in an off state or an on state, a voltage across the switching unit 3020 becomes large instantaneously, a current of a branch where the switching unit 3020 and the inductance unit 3023 are connected in series becomes large, and then a voltage across the switching unit 3020 and the inductance unit 3023 which are connected in series becomes large. That is, the voltage across the second clamp unit 3022 and the discharge unit 3024 increases after they are connected in series. When the voltage across the second clamping unit 3022 increases to a first preset voltage (i.e., a voltage required for the turn-on operation of the second clamping unit 3022), the second clamping unit 3022 is turned on, and the voltage of the second clamping unit 3022 itself is clamped at a fixed value; when the voltage across the discharge unit 3024 increases to a second predetermined voltage (i.e., the voltage required for the turn-on operation of the discharge unit 3024), the discharge unit 3024 turns on. In other words, when the voltage across the switch unit 3020 and the inductor unit 3023 after being connected in series is greater than the sum of the first preset voltage and the second preset voltage, the second clamping unit 3022 performs a clamping function, and the discharge unit 3024 conducts the discharge. That is, the branch where the second clamping unit 3022 and the discharging unit 3024 are connected in series is turned on.

Optionally, in some possible embodiments, after the lightning stroke is ended, after the voltage across the switching unit 3020 is smaller than the breakdown voltage of the transient suppression diode or smaller than the threshold voltage of the varistor, if the switching unit 3020 is in the off state, the voltage across the second clamping unit 3022 and the discharging unit 3024 is the power voltage, and since the power voltage is smaller than the sum of the third preset voltage (i.e., the voltage required for turning on and maintaining the second clamping unit 3022) and the fourth preset voltage (i.e., the voltage required for turning on and maintaining the discharging unit 3024), the discharging unit 3024 automatically turns off, and stops discharging.

For example, the switching unit 3020 may be switched from an on state to an off state when a preset condition is satisfied. The preset condition may be, for example, when the current of the discharge unit 3024 is smaller than a first preset current threshold or smaller than a second preset current threshold, or when the voltage across the discharge unit 3024 is smaller than the voltage required for maintaining the turn-on of the discharge unit 3024. Or the switching unit 3020 may switch from the on state to the off state after a preset period of time, which may be empirically set. Alternatively, the switching unit 3020 may be always in the off state. The state control of the switch unit 3020 is not limited in the embodiments of the present application, and the state control of the switch unit 3020 may be adjusted according to specific practical requirements.

In the embodiment of the present application, the first clamping unit 3021 may protect the switch unit 3020; the second clamping unit 3022 may increase the turn-off voltage of the discharge unit 3024, that is, the second clamping unit 3022 may prevent the discharge unit 3024 from being unable to turn off automatically when the switch unit 3020 is in the off state, so that the discharge unit 3024 is always turned on, the load 31 is always connected to the power source through the branch where the discharge unit 3024 and the second clamping unit 3022 are connected in series, and the load 31 is always in the power-on state. Therefore, the embodiment of the application can carry out lightning protection on the switch unit, and the discharge unit can be automatically turned off after the lightning protection is finished, so that the safety is good, and the reliability is high.

Alternatively, in some possible embodiments, the second clamping unit 3022 may be at least one of a transient suppression diode and a varistor.

In a specific implementation, when the second clamping unit 3022 is a transient suppression diode, the first preset voltage is a voltage required for a turn-on action of the transient suppression diode, that is, a breakdown voltage of the transient suppression diode; the third predetermined voltage is a voltage required for maintaining the turn-on of the transient suppression diode, i.e., an on-state voltage of the transient suppression diode.

When the second clamping unit 3022 is a varistor, the first preset voltage is a voltage required for the on-state of the varistor, that is, a critical voltage of the varistor; the third preset voltage is a voltage required for maintaining the conduction of the voltage dependent resistor, namely the on-state voltage of the voltage dependent resistor.

When the second clamping unit 3022 is a transient suppression diode and a varistor connected in series with the transient suppression diode, the first preset voltage is the sum of the breakdown voltage of the transient suppression diode and the threshold voltage of the varistor, and the third preset voltage is the sum of the on-state voltage of the transient suppression diode and the on-state voltage of the varistor.

It is to be explained that the transient suppression diode has a fast response speed; the piezoresistor has a relatively high current capacity and a relatively low cost, and in specific production practice, at least one of the transient suppression diode and the piezoresistor is selected according to requirements.

Alternatively, in some possible embodiments, the discharge unit 3024 includes a gas discharge tube or a semiconductor discharge tube.

In a specific implementation, when the discharge unit 3024 is a gas discharge tube, the second preset voltage is a voltage required for the gas discharge tube to conduct, that is, a voltage for conducting through a gap discharge between two electrodes of the gas discharge tube; the fourth preset voltage is the voltage required for maintaining the conduction of the gas discharge tube, namely the on-state voltage of the gas discharge tube. It is understood that the on-state voltage of the gas discharge tube is less than the breakdown conduction voltage of the gas discharge tube.

When the discharge unit 3024 is a semiconductor discharge tube, the second preset voltage is a voltage required for the conduction operation of the semiconductor discharge tube, i.e., a breakdown voltage of a semiconductor; the fourth preset voltage is the voltage required for maintaining the conduction of the semiconductor discharge tube, namely the on-state voltage of the semiconductor discharge tube. It is understood that the on-state voltage of the semiconductor discharge tube is less than the breakdown voltage of the semiconductor discharge tube.

In general, the fourth predetermined voltage is less than the second predetermined voltage.

It will be appreciated that, with respect to a gas discharge tube, a semiconductor discharge tube having a breakdown voltage less than that of the gas discharge tube and an on-state voltage less than that of the gas discharge tube, the inductance of the corresponding inductive element 3023 when the discharge element 3024 is embodied as a semiconductor discharge tube is less than the inductance of the inductive element 3023 when the discharge element 3024 is embodied as a gas discharge tube. The conduction speed of the semiconductor discharge tube is faster than that of the gas discharge tube.

In some possible embodiments, referring to fig. 4, fig. 4 is a circuit diagram of a switching device provided in an embodiment of the present application. As shown in fig. 4, the first clamping unit is embodied as a transient suppression diode D ₄₁ The second clamping unit is embodied as a piezoresistor R ₄₁ The switching unit is embodied as a MOSFET switching tube Q ₄₁ The inductance unit is embodied as an inductance L ₄₁ The discharge unit being embodied as a gas discharge tube GT ₄₁ 。

At this time, the switch tube Q ₄₁ Is connected with the first end of the power lightning protection unit 401 and the transient suppression diode D ₄₁ And a varistor R ₄₁ One end of (1), a switching tube Q ₄₁ Drain electrode of (1) is connected with an inductor L ₄₁ And a transient suppression diode D ₄₁ Another end of (1), inductance L ₄₁ Is connected to the first end of the load 41 and the gas discharge tube GT ₄₁ One end of (GT) a gas discharge tube GT ₄₁ The other end of the resistor is connected with a piezoresistor R ₄₁ And a second end of the load 41 is connected to a second end of the power lightning protection unit 401.

In the embodiment of the present application, if the switch tube Q ₄₁ In a conducting state, when lightning strike occurs, the switch tube Q ₄₁ The voltage at both ends is increased and flows through the switch tube Q ₄₁ And an inductance L ₄₁ When the current of the switch tube Q is increased ₄₁ And an inductance L ₄₁ The voltage across increases. When the switch tube Q ₄₁ And an inductance L ₄₁ The voltage at both ends is increased to the gas discharge tube GT ₄₁ Voltage required for conduction and varistor R ₄₁ When the sum of the voltages required for the conduction operation is reached, the gas discharge tube GT ₄₁ And a varistor R ₄₁ Conducting when the lightning current can pass through the gas discharge tube GT ₄₁ And a varistor R ₄₁ Shunted back into the mains lightning protection unit 401. After the lightning stroke is over, the switch tube Q ₄₁ The voltage between the source electrode and the drain electrode is within a safe voltage range, and the switching tube Q ₄₁ Is turned off when applied to the gas discharge tube GT ₄₁ And a varistor R ₄₁ The voltage at both ends is the supply voltage, since the supply voltage is smaller than the gas discharge tube GT ₄₁ Voltage required for maintaining conduction and voltage dependent resistor R ₄₁ The sum of the voltages required for conduction maintenance, gas discharge tube GT ₄₁ And automatically turning off. Or, after the lightning stroke is finished, the switching tube Q ₄₁ The voltage between the source electrode and the drain electrode is within a safe voltage range, and the switching tube Q ₄₁ Still in a conducting state, the gas discharge tube GT ₄₁ And a varistor R ₄₁ Short-circuited gas discharge tube GT ₄₁ And a varistor R ₄₁ The voltage at both ends is less than that of the gas discharge tube GT ₄₁ Voltage required for maintaining conduction and voltage dependent resistor R ₄₁ The gas discharge tube GT is turned on to maintain the sum of the required voltages ₄₁ And can also be automatically turned off.

If the switch tube Q ₄₁ In the off state, when lightning stroke occurs, the switch tube Q ₄₁ A transient suppression diode D with increased voltage at both ends ₄₁ Is conducted and flows through the transient suppression diode D ₄₁ And an inductance L ₄₁ Is increased, the transient suppression diode D ₄₁ And an inductance L ₄₁ The voltage across increases. Transient suppression diode D ₄₁ And an inductance L ₄₁ The voltage at both ends is increased to the gas discharge tube GT ₄₁ Voltage required for conduction and varistor R ₄₁ When the sum of the voltages required for the conduction operation is reached, the gas discharge tube GT ₄₁ And a varistor R ₄₁ Conducting when the lightning current can pass throughGas discharge tube GT ₄₁ And a varistor R ₄₁ Shunted back into the mains lightning protection unit 401. After the lightning stroke is over, the switch tube Q ₄₁ Is within a safe voltage range, a transient suppression diode D ₄₁ Is turned off when applied to the gas discharge tube GT ₄₁ And a varistor R ₄₁ The voltage at both ends is the supply voltage, since the supply voltage is smaller than the gas discharge tube GT ₄₁ Voltage required for maintaining conduction and voltage dependent resistor R ₄₁ The sum of the voltages required for conduction maintenance, gas discharge tube GT ₄₁ And automatically turning off.

Alternatively, in some possible embodiments, replacing the gas discharge tube in fig. 4 with a semiconductor discharge tube may result in the switching device shown in fig. 5. As shown in fig. 5, the first clamping unit is embodied as a transient suppression diode D ₅₁ The second clamping unit is embodied as a varistor R ₅₁ The switching unit is embodied as a MOSFET switching tube Q ₅₁ The inductance unit is embodied as an inductance L ₅₁ The discharge unit being embodied as a semiconductor discharge tube GT ₅₁ 。

At this time, the switch tube Q ₅₁ Is connected to the first end of the power lightning protection unit 501 and the transient suppression diode D ₅₁ And a varistor R ₅₁ One end of (1), a switching tube Q ₅₁ Drain electrode of (1) is connected with an inductor L ₅₁ And a transient suppression diode D ₅₁ Another end of (1), inductance L ₅₁ Is connected to a first end of the load 51 and the semiconductor discharge tube GT ₅₁ One end of (GT), a semiconductor discharge tube GT ₅₁ The other end of the resistor is connected with a piezoresistor R ₅₁ And a second end of the load 51 is connected to a second end of the power lightning protection unit 501.

Similarly, in the embodiment of the present application, if the switch tube Q is connected to the power supply ₅₁ In a conducting state, when lightning strike occurs, the switch tube Q ₅₁ The voltage at both ends is increased and flows through the switch tube Q ₅₁ And an inductance L ₅₁ When the current of the switch tube Q is increased ₅₁ And an inductance L ₅₁ The voltage across increases. When the switch tube Q ₅₁ And an inductance L ₅₁ Voltage increase at both endsLarge to semiconductor discharge tube GT ₅₁ Voltage required for conduction and varistor R ₅₁ Semiconductor discharge tube GT for the sum of voltages required for conduction ₅₁ And a varistor R ₅₁ Conducting when the lightning current can pass through the semiconductor discharge tube GT ₅₁ And a varistor R ₅₁ Shunted back into the mains lightning protection unit 501. After the lightning stroke is over, the switch tube Q ₅₁ The voltage between the source electrode and the drain electrode is within a safe voltage range, and the switching tube Q ₅₁ Is turned off when applied to the semiconductor discharge tube GT ₅₁ And a varistor R ₅₁ The voltage across the two terminals is the supply voltage, since the supply voltage is smaller than the semiconductor discharge tube GT ₅₁ Voltage required for maintaining conduction and voltage dependent resistor R ₅₁ A semiconductor discharge tube GT for maintaining the sum of voltages required for conduction ₅₁ And automatically turning off. Or, after the lightning stroke is finished, the switching tube Q ₅₁ The voltage between the source electrode and the drain electrode is within a safe voltage range, and the switching tube Q ₅₁ Still in a conductive state, the semiconductor discharge tube GT ₅₁ And a varistor R ₅₁ Short-circuited, semiconductor discharge tube GT ₅₁ And a varistor R ₅₁ The voltage at both ends is less than that of the semiconductor discharge tube GT ₅₁ Voltage required for maintaining conduction and voltage dependent resistor R ₅₁ The semiconductor discharge tube GT is used to maintain the sum of the voltages required for conduction ₅₁ And can also be automatically turned off.

If the switch tube Q ₅₁ In the off state, when lightning stroke occurs, the switch tube Q ₅₁ A transient suppression diode D with increased voltage at both ends ₅₁ Is conducted and flows through the transient suppression diode D ₅₁ And an inductance L ₅₁ Is increased, the transient suppression diode D ₅₁ And an inductance L ₅₁ The voltage across increases. Transient suppression diode D ₅₁ And an inductance L ₅₁ The voltage at both ends is increased to the semiconductor discharge tube GT ₅₁ Voltage required for conduction and varistor R ₅₁ Semiconductor discharge tube GT for the sum of voltages required for conduction ₅₁ And a varistor R ₅₁ Conducting when the lightning current can pass through the semiconductor discharge tube GT ₅₁ And a varistor R ₅₁ Shunting back to power supply for lightning protectionIn cell 501. After the lightning stroke is over, the switch tube Q ₅₁ Is within a safe voltage range, a transient suppression diode D ₅₁ Is turned off when applied to the semiconductor discharge tube GT ₅₁ And a varistor R ₅₁ The voltage across the two terminals is the supply voltage, since the supply voltage is smaller than the semiconductor discharge tube GT ₅₁ Voltage required for maintaining conduction and voltage dependent resistor R ₅₁ A semiconductor discharge tube GT for maintaining the required voltage ₅₁ And automatically turning off.

Compared with the switching device shown in fig. 4 which uses a gas discharge tube, the switching device in the embodiment of the present application uses a semiconductor discharge tube, and since the voltage (i.e., the breakdown voltage) required for the turn-on operation of the semiconductor discharge tube is smaller than the voltage (i.e., the breakdown voltage) required for the turn-on operation of the gas discharge tube, and the voltage (i.e., the on-state voltage) required for the turn-on maintenance of the semiconductor discharge tube is smaller than the voltage (i.e., the on-state voltage) required for the turn-on maintenance of the gas discharge tube, the inductance L is smaller than the voltage (i.e., the on-state voltage) required for the turn-on maintenance of the gas discharge tube ₅₁ Can be less than the inductance L ₄₁ The feeling of (1). Because the inductance of the inductor is in positive correlation with the volume of the inductor and the cost of the inductor, the volume and the cost of the inductor unit can be reduced by implementing the embodiment of the application.

Alternatively, in some possible embodiments, replacing the piezoresistors in fig. 5 with transient suppression diodes may result in the switching device shown in fig. 6. As shown in fig. 6, the first clamping unit is embodied as a transient suppression diode D ₆₁ The second clamping unit is embodied as a transient suppression diode D ₆₂ The switching unit is embodied as a MOSFET switching tube Q ₆₁ The inductance unit is embodied as an inductance L ₆₁ The discharge unit being embodied as a semiconductor discharge tube GT ₆₁ 。

At this time, the switch tube Q ₆₁ The source electrode of the power supply lightning protection unit 601 is connected with the first end of the power supply lightning protection unit 601 and the transient suppression diode D ₆₁ And a transient suppression diode D ₆₂ One end of (1), a switching tube Q ₆₁ Drain electrode of (1) is connected with an inductor L ₆₁ And a transient suppression diode D ₆₁ The other end of (2), inductance L ₆₁ The other end of which is connected to a load 61First terminal and semiconductor discharge tube GT ₆₁ One end of the semiconductor discharge tube GT ₆₁ Is connected with a transient suppression diode D ₆₂ And the second end of the load 61 is connected to the second end of the power lightning protection unit 601.

The implementation principle of the embodiment of the present application can be described with reference to fig. 5, and is different from the case of using a voltage dependent resistor as the second clamping unit in fig. 5 in that the embodiment of the present application uses a transient suppression diode as the second clamping unit.

Optionally, in some possible embodiments, the voltage dependent resistor in fig. 4 may be replaced by a transient suppression diode (not shown in the figure). Alternatively, the transient suppression diode employed as the first clamping unit in fig. 4 to 6 may be replaced with a varistor (not shown in the drawings) employed as the first clamping unit. Alternatively, a varistor and a transient suppression diode may be connected in series as the first clamping unit or the second clamping unit (not shown in the figure). In general, the first clamping unit and the second clamping unit may have various possible implementations.

Optionally, referring to fig. 7, fig. 7 is a block diagram of another structure of the switching device provided in the embodiment of the present application. As shown in fig. 7, the switching device 702 is disposed between the power lightning protection unit 701 and the load 71. The switching device 702 includes a switching unit 7020, a first clamping unit 7021, an inductance unit 7023, and a discharge unit 7024.

The switching unit 7020 is connected in series with the inductance unit 7023, one end of the switching unit 7020, which is connected in series with the inductance unit 7023, is connected to a first end of the power lightning protection unit 701 and one end of the discharge unit 7024, the other end of the switching unit 7020, which is connected in series with the inductance unit 7023, is connected to a first end of the load 71 and the other end of the discharge unit 7024, and a second end of the load 71 is connected to a second end of the power lightning protection unit 701; the first clamping unit 7021 is connected in parallel to both ends of the switching unit 7020.

For example, the first end of the power lightning protection unit 701 may be a positive end, and the first end of the load 71 is also a positive end, so that the switch unit 7020 and the inductance unit 7023 are connected in series to a positive bus between the power lightning protection unit 701 and the load 71. Or, the first end of the power lightning protection unit 701 may be a negative end, and the first end of the load 71 is also a negative end, so that the switch unit 7020 and the inductance unit 7023 are connected in series to a negative bus between the power lightning protection unit 701 and the load 71. Whether the switching unit 7020 and the inductance unit 7023 are connected in series on the positive bus or the negative bus, the switching unit may control on or off of the connection between the power lightning protection unit 701 and the load 71.

The inductance unit 7023 may limit the current of the switching unit 7020 or limit the current of the first clamping unit 7021 during the transient voltage change at the two ends of the switching unit 7020. The inductance unit 7023 includes one or more inductances, and the inductances may be connected in series or in parallel, that is, the number of inductances in the inductance unit and the connection manner of the inductances are not limited in this embodiment of the application.

The first clamping unit 7021 includes at least one of a transient suppression diode and a varistor. In a specific implementation, when the switching unit 7020 is in an off state and a lightning strike occurs, that is, when the voltage across the switching unit 7020 is greater than the breakdown voltage of the transient suppression diode, the transient suppression diode is turned on, and the voltage across the switching unit 7020 is clamped to the clamping voltage of the transient suppression diode. Similarly, the voltage dependent resistor may clamp the voltage across the switch unit 7020 to a fixed voltage value when a lightning strike occurs when the voltage across the switch unit 7020 is greater than a critical voltage of the voltage dependent resistor when the switch unit is in an off state. It is understood that the clamping voltage of the transient suppression diode and the voltage value clamped and fixed by the voltage dependent resistor are smaller than the withstand voltage of the switching unit 7020. I.e., the transient suppression diode and the varistor, may protect switching element 7020 when switching element 7020 is in an off state.

The discharging unit 7024 may discharge the lightning strike current into the power lightning protection unit 701, so as to implement lightning protection of the switching unit 7020. In a specific implementation, when a lightning strike occurs, no matter the switching unit 7020 is in an off state or an on state, the voltage across the switching unit 7020 becomes larger instantaneously, the current of the branch where the switching unit 7020 and the inductance unit 7023 are connected in series becomes larger, and then the voltage across the switching unit 7020 and the inductance unit 7023 are connected in series becomes larger. That is, the voltage across discharge cell 7024 becomes larger after being connected in series. When the voltage across discharge unit 7024 increases to a second predetermined voltage (i.e., the voltage required for the turn-on operation of discharge unit 7024), discharge unit 7024 turns on. I.e., the branch in which the discharging unit 7024 is located is turned on.

With respect to the switching device shown in fig. 3, the switching device provided in the embodiment of the present application includes a first clamping unit 7021, and the first clamping unit 7021 may protect the switching unit 7020.

In some possible embodiments, referring to fig. 8, fig. 8 is a circuit diagram of a switching device provided in an embodiment of the present application. As shown in fig. 8, the first clamping unit is embodied as a transient suppression diode D ₈₁ The switching unit is embodied as a MOSFET switching tube Q ₈₁ The inductance unit is embodied as an inductance L ₈₁ The discharge unit being embodied as a gas discharge tube GT ₈₁ 。

At this time, the switch tube Q ₈₁ The source of the power source is connected with the first end of the power source lightning protection unit 801 and the transient suppression diode D ₈₁ And a gas discharge tube GT ₈₁ One end of (1), a switching tube Q ₈₁ Drain electrode of (1) is connected with an inductor L ₈₁ And a transient suppression diode D ₈₁ Another end of (1), inductance L ₈₁ Is connected to the first end of the load 81 and the gas discharge tube GT ₈₁ And a second end of the load 81 is connected to a second end of the power lightning protection unit 801.

In the embodiment of the present application, if the switch tube Q ₈₁ In a conducting state, when lightning strike occurs, the switch tube Q ₈₁ The voltage at both ends is increased and flows through the switch tube Q ₈₁ And an inductance L ₈₁ When the current of the switch tube Q is increased ₈₁ And an inductance L ₈₁ The voltage across increases. When the switch tube Q ₈₁ And an inductance L ₈₁ The voltage at both ends is increased to the gas discharge tube GT ₈₁ At the voltage required for conduction operation, the gas discharge tube GT ₈₁ Conducting when the lightning current can pass through the gas discharge tube GT ₈₁ Shunted back into the mains lightning protection unit 801. After the lightning stroke is finished, the switch tube Q ₈₁ The voltage between the source electrode and the drain electrode is in a safe voltage range, and the switching tube Q is kept ₈₁ Conductive, gas discharge tube GT ₈₁ Is short-circuited and the switching tube Q is ₈₁ And an inductance L ₈₁ The voltage at both ends is less than a gas discharge tube GT ₈₁ A gas discharge tube GT for maintaining the voltage required for conduction ₈₁ And automatically turning off.

If the switch tube Q ₈₁ In the off state, when lightning strike occurs, the switch tube Q ₈₁ A transient suppression diode D with increased voltage at both ends ₈₁ Is conducted and flows through the transient suppression diode D ₈₁ And an inductance L ₈₁ Is increased, the transient suppression diode D ₈₁ And an inductance L ₈₁ The voltage across increases. Transient suppression diode D ₈₁ And an inductance L ₈₁ The voltage at both ends is increased to the gas discharge tube GT ₈₁ At the voltage required for conduction operation, the gas discharge tube GT ₈₁ Conducting when the lightning current can pass through the gas discharge tube GT ₈₁ Shunted back into the mains lightning protection unit 801. Even after the lightning stroke is over, the switch tube Q ₈₁ Is within a safe voltage range, a transient suppression diode D ₈₁ Is turned off due to the application of the current to the gas discharge tube GT ₈₁ The voltage across both ends is a supply voltage greater than a gas discharge tube GT ₈₁ A gas discharge tube GT for maintaining the voltage required for conduction ₈₁ Cannot be automatically turned off and passes through a gas discharge tube GT ₈₁ Is still greater than the first predetermined current threshold. At this time, the switch tube Q ₈₁ Switching from an OFF state to an ON state to discharge the gas discharge tube GT ₈₁ The voltage across both ends is reduced to be smaller than the gas discharge tube GT ₈₁ Turn on maintains the required voltage. Of course, during a lightning strike, the gas discharge tube GT ₈₁ After the switch-on, the switch tube Q does not need to wait until the lightning stroke is finished ₈₁ It is also possible to switch from an off-state to an on-state. That is, the second clamping unit is reduced in the embodiment of the present application, and the gas discharge tube can be turned off by closing the switching unit.

Alternatively, in some possible implementationsIn the embodiment, the gas discharge tube in fig. 8 is replaced with a semiconductor discharge tube, and the switching device shown in fig. 9 can be obtained. As shown in fig. 9, the first clamping unit is embodied as a transient suppression diode D ₉₁ The switching unit is embodied as a MOSFET switching tube Q ₉₁ The inductance unit is embodied as an inductance L ₉₁ The discharge unit being embodied as a semiconductor discharge tube GT ₉₁ 。

At this time, the switch tube Q ₉₁ Is connected with the first end of the power supply lightning protection unit 901 and the transient suppression diode D ₉₁ And a semiconductor discharge tube GT ₉₁ One end of (1), a switching tube Q ₉₁ Drain electrode of (1) is connected with an inductor L ₉₁ And a transient suppression diode D ₉₁ The other end of (2), inductance L ₉₁ Is connected to the first end of the load 91 and the semiconductor discharge tube GT ₉₁ And the second end of the load 91 is connected to the second end of the power lightning protection unit 901.

In the embodiment of the present application, if the switch tube Q ₉₁ In a conducting state, when lightning strike occurs, the switch tube Q ₉₁ The voltage at both ends is increased and flows through the switch tube Q ₉₁ And an inductance L ₉₁ When the current of the switch tube Q is increased ₉₁ And an inductance L ₉₁ The voltage across increases. When the switch tube Q ₉₁ And an inductance L ₉₁ The voltage at both ends is increased to the semiconductor discharge tube GT ₉₁ At the voltage required for conduction operation, the semiconductor discharge tube GT ₉₁ Conducting when the lightning current can pass through the semiconductor discharge tube GT ₉₁ Shunted back into the mains lightning protection unit 901. After the lightning stroke is finished, the switch tube Q ₉₁ The voltage between the source electrode and the drain electrode is in a safe voltage range, and the switching tube Q is kept ₉₁ Conductive, semiconductor discharge tube GT ₉₁ Is short-circuited and the switching tube Q is ₉₁ And an inductance L ₉₁ The voltage across both ends being less than a semiconductor discharge tube GT ₉₁ A semiconductor discharge tube GT for maintaining the required voltage ₉₁ And automatically turning off.

If the switch tube Q ₉₁ In the off state, when lightning strike occurs, the switch tube Q ₉₁ Voltage increase at both ends, transient suppression diode D ₉₁ Is conducted and flows through the transient suppression diode D ₉₁ And an inductance L ₉₁ Is increased, the transient suppression diode D ₉₁ And an inductance L ₉₁ The voltage across increases. Transient suppression diode D ₉₁ And an inductance L ₉₁ The voltage at both ends is increased to the semiconductor discharge tube GT ₉₁ At the voltage required for conduction operation, the semiconductor discharge tube GT ₉₁ Conducting when the lightning current can pass through the semiconductor discharge tube GT ₉₁ Shunted back into the mains lightning protection unit 901. Even after the lightning stroke is over, the switch tube Q ₉₁ Is within a safe voltage range, and a transient suppression diode D ₉₁ Is turned off due to the application of the current to the semiconductor discharge tube GT ₉₁ Is a supply voltage which is greater than a semiconductor discharge tube GT ₉₁ A semiconductor discharge tube GT for maintaining the required voltage ₉₁ Cannot be automatically turned off and passes through the semiconductor discharge tube GT ₉₁ The current of (a) is still larger than the second preset current threshold. At this time, the switch tube Q ₉₁ Switching from an OFF state to an ON state to discharge the semiconductor discharge tube GT ₉₁ The voltage at both ends is reduced to be smaller than that of the semiconductor discharge tube GT ₉₁ Turning on maintains the required voltage. Of course, during a lightning strike, the semiconductor discharge tube GT ₉₁ After the conduction, the switch tube Q does not need to wait for the lightning stroke to end ₉₁ It is also possible to switch from the off-state to the on-state. That is, the second clamping unit is reduced in the embodiment of the present application, and the semiconductor discharge tube can be turned off by closing the switching unit.

Alternatively, in some possible embodiments, the discharge unit may include M gas discharge tubes connected in series, where M is greater than or equal to 2.

Exemplarily, referring to fig. 10, fig. 10 is a further circuit diagram of a switching device provided in an embodiment of the present application. As shown in fig. 10, the first clamping unit is embodied as a transient suppression diode D ₁₀₁ The switching unit is embodied as a MOSFET switching tube Q ₁₀₁ The inductance unit is embodied as an inductance L ₁₀₁ The discharge unit is embodied as 3 gas discharge tubes (e.g. gas discharge tube GT) connected in series ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ )。

At this time, the switch tube Q ₁₀₁ Is connected to the first end of the power lightning protection unit 1001 and the transient suppression diode D ₁₀₁ And a gas discharge tube GT ₁₀₁ One end of (1), a switching tube Q ₁₀₁ Drain electrode of (1) is connected with an inductor L ₁₀₁ And a transient suppression diode D ₁₀₁ Another end of (1), inductance L ₁₀₁ Is connected to the first end of the load 101 and the gas discharge tube GT ₁₀₃ One end of (GT) a gas discharge tube GT ₁₀₃ Is connected with a gas discharge tube GT at the other end ₁₀₂ One end of (GT) a gas discharge tube GT ₁₀₂ Is connected with a gas discharge tube GT at the other end ₁₀₁ And a second end of the load 101 is connected to a second end of the power lightning protection unit 1001.

In the embodiment of the present application, if the switch tube Q ₁₀₁ In a conducting state, when lightning strike occurs, the switch tube Q ₁₀₁ The voltage at both ends is increased and flows through the switch tube Q ₁₀₁ And an inductance L ₁₀₁ When the current of the switch tube Q is increased ₁₀₁ And an inductance L ₁₀₁ The voltage across increases. When the switch tube Q ₁₀₁ And an inductance L ₁₀₁ The voltage at both ends is increased to the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ The gas discharge tube GT when the voltage needed by the conduction action is added ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Conducting when the lightning current can pass through the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Shunted back into the mains lightning protection unit 1001. After the lightning stroke is finished, the switch tube Q ₁₀₁ The voltage between the source electrode and the drain electrode is within a safe voltage range, and the switching tube Q ₁₀₁ Can be turned off when applied to the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Is a power supply voltage, since the power supply voltage is smaller than the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ A gas discharge tube GT for maintaining the voltage required for conduction ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ And automatically turning off. Or, after the lightning stroke is finished, the switching tube Q ₁₀₁ The voltage between the source electrode and the drain electrode is within a safe voltage range, and the switching tube Q ₁₀₁ Still in a conducting state, the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Short-circuited gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ After series connection, the voltage at two ends is less than GT of gas discharge tube ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ When the required voltage is maintained, the gas discharge tube GT is turned on ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ And automatically turning off.

If the switch tube Q ₁₀₁ In the off state, when lightning strike occurs, the switch tube Q ₁₀₁ A transient suppression diode D with increased voltage at both ends ₁₀₁ Is conducted and flows through the transient suppression diode D ₁₀₁ And an inductance L ₁₀₁ Is increased, the transient suppression diode D ₁₀₁ And an inductance L ₁₀₁ The voltage across increases. Transient suppression diode D ₁₀₁ And an inductance L ₁₀₁ The voltage at both ends is increased to the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ When the sum of the voltages required for the conduction operation is reached, the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Conducting when the lightning current can pass through the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Shunted back into the mains lightning protection unit 1001. After the lightning stroke is finished, the switch tube Q ₁₀₁ Is within a safe voltage range, a transient suppression diode D ₁₀₁ Is turned off due to the application of the current to the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Is a power supply voltage which is less than the voltage required for maintaining the conduction of 3 gas discharge tubes GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ Can be automatically carried outAnd (6) turning off. That is, with respect to the embodiment described in fig. 8, by increasing the number of gas discharge tubes, the embodiment of the present application can avoid that the gas discharge tubes cannot be automatically turned off after the lightning stroke is over, and further closing the switch unit is not needed to turn off the gas discharge tubes.

Optionally, in some possible embodiments, the discharge unit may further include M-1 capacitor units. It should be first explained that the capacitance unit may include one or more capacitors, and the capacitors may be connected in series or in parallel. The capacitor unit shown in fig. 10 specifically includes one capacitor, and it should be understood that this application is not limited to the number of capacitors included in the capacitor unit and the connection manner of the capacitors.

As shown in FIG. 10, the discharge unit further includes a capacitor C ₁₀₁ And a capacitor C ₁₀₂ . Wherein, the capacitor C ₁₀₁ One end of which is connected to the common node and a capacitor C ₁₀₁ Is connected at the other end to the gas discharge tube GT ₁₀₁ And a gas discharge tube GT ₁₀₂ To (c) to (d); capacitor C ₁₀₂ Also connected to a common node, a capacitor C ₁₀₂ Is connected at the other end to the gas discharge tube GT ₁₀₂ And gas discharge tube GT ₁₀₃ In the meantime. In this case, the common node is a gas discharge tube GT ₁₀₁ One end of the lightning protection unit 1001 is connected. Optionally, the common node may also be a gas discharge tube GT ₁₀₃ To which one end (not shown) of a load 101 is connected.

In general, the common node can be any end of the M gas discharge tubes connected in series.

It will be appreciated that the capacitance C ₁₀₁ And a capacitor C ₁₀₂ Gas discharge tube GT can be accelerated ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ And reducing the conduction speed of the gas discharge tube GT ₁₀₁ Gas discharge tube GT ₁₀₂ And a gas discharge tube GT ₁₀₃ The voltage required for the turn-on operation.

Alternatively, in some possible embodiments, two or more semiconductor discharge tubes may be connected in series as a discharge unit (not shown in the figure), and the effect of the embodiment described in fig. 10 may be achieved as well.

Alternatively, in some possible embodiments, N series-connected gas discharge tubes may be integrated into one N-layer gas discharge tube, where N is greater than or equal to 2.

In some possible embodiments, the discharge unit may further include N-1 capacitive units, and the N-layer gas discharge tube includes N-1 capacitive terminals in addition to the input terminal and the output terminal. At this time, a capacitor unit is connected between the first terminal and a capacitor terminal of the N-layer gas discharge tube. The first end of the N layers of gas discharge tubes is the input end or the output end of the N layers of gas discharge tubes, namely, the first end is any end of the N gas discharge tubes after being connected in series.

Illustratively, the 3 series-connected gas discharge tubes shown in FIG. 10 are integrated into one 3-layer gas discharge tube. At this moment, this 3 layers of gas discharge tube includes input end, output and 2 electric capacity ends, and the circuit diagram that obtains is shown in fig. 10, 3 components and parts when 3 gas discharge tubes in the difference of fig. 10, and this application embodiment specifically integrates 3 gas discharge tubes into 1 3 layers of gas discharge tubes, and what can see is only one component and part.

Alternatively, in some possible implementations, the transient suppression diode in the embodiment described in fig. 8 to 10 may be replaced by a voltage dependent resistor, or the transient suppression diode is connected in series with a voltage dependent resistor, etc. (not shown in the figure).

It should be noted that the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The above described division of the unit is only a logic function division, and there may be other division ways in actual implementation, such as: multiple units or components may be combined, or may be integrated into another system, or some features may be omitted, or not implemented. In addition, the coupling, direct coupling or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between the devices or units may be electrical, mechanical or in other forms.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The switching device is characterized by being arranged between a power supply lightning protection unit and a load, and comprising a switching unit, two clamping units, an inductance unit and a discharge unit; the two clamping units comprise a first clamping unit and a second clamping unit; wherein the content of the first and second substances,

the switch unit is connected with the inductance unit in series, one end of the switch unit after being connected with the inductance unit in series is connected with the first end of the power supply lightning protection unit, and the other end of the switch unit after being connected with the inductance unit in series is connected with the first end of the load;

the first clamping unit is connected in parallel to two ends of the switch unit;

the second clamping unit is connected with the discharge unit in series, one end of the second clamping unit, which is connected with the discharge unit in series, is connected with the first end of the power supply lightning protection unit, and the other end of the second clamping unit, which is connected with the discharge unit in series, is connected with the first end of the load;

and the second end of the power supply lightning protection unit is connected with the second end of the load.

2. The switching device according to claim 1, wherein either of the two clamping units comprises at least one of a transient suppression diode and a varistor.

3. The switching device according to any one of claims 1-2, wherein the discharge unit comprises a gas discharge tube or a semiconductor discharge tube.

4. A switching device is characterized in that the switching device is arranged between a power supply lightning protection unit and a load, and comprises a switching unit, a clamping unit, an inductance unit and a discharge unit; wherein the content of the first and second substances,

the switch unit is connected with the inductance unit in series, one end of the switch unit, which is connected with the inductance unit in series, is connected with the first end of the power supply lightning protection unit and one end of the discharge unit, and the other end of the switch unit, which is connected with the inductance unit in series, is connected with the first end of the load and the other end of the discharge unit;

the clamping units are connected in parallel at two ends of the switch unit;

5. The switching device according to claim 4, wherein the discharge unit comprises a gas discharge tube; the switching unit is used for switching from an off state to an on state when the current of the gas discharge tube is larger than a first preset current threshold value, so that the voltage at two ends of the gas discharge tube is smaller than the voltage required by the gas discharge tube for maintaining conduction.

6. The switching device according to claim 4, wherein the discharge unit comprises a semiconductor discharge tube; the switching unit is used for switching from an off state to an on state under the condition that the current of the semiconductor discharge tube is larger than a second preset current threshold value, so that the voltage at two ends of the semiconductor discharge tube is smaller than the voltage required by the conduction and maintenance of the semiconductor discharge tube.

7. The switching device according to claim 4, wherein the discharge unit comprises an N-layer gas discharge tube; wherein N is greater than or equal to 2.

8. The switching device of claim 7, wherein the discharge unit further comprises N-1 capacitive units; the N layers of gas discharge tubes comprise input ends, output ends and N-1 capacitor ends;

wherein one of the N-1 capacitive units is connected between the first end of the N layers of gas discharge tubes and one of the N-1 capacitive ends; and the first ends of the N layers of gas discharge tubes are input ends or output ends of the N layers of gas discharge tubes.

9. The switching device of claim 4, wherein the discharge unit comprises M gas discharge tubes connected in series, wherein M is greater than or equal to 2.

10. The switching device according to claim 9, wherein the discharge unit further comprises M-1 capacitive units; wherein the content of the first and second substances,

one of the M-1 capacitive units is connected between the common node and an intermediate node; the common node is any end of the M gas discharge tubes after being connected in series; the middle node is a series connection point of any two gas discharge tubes in the M gas discharge tubes.

11. A power supply apparatus, characterized in that it comprises a power supply lightning protection unit and at least one switching device according to any one of claims 1-3;

the power supply lightning protection unit is used for receiving the current of the discharge unit in the switch device.

12. A power supply apparatus, characterized in that it comprises a power supply lightning protection unit and at least one switching device according to any one of claims 4-10;