WO2014067272A1

WO2014067272A1 - Protective apparatus

Info

Publication number: WO2014067272A1
Application number: PCT/CN2013/074806
Authority: WO
Inventors: 王庆海; 丁学英
Original assignee: 华为技术有限公司
Priority date: 2012-10-31
Filing date: 2013-04-26
Publication date: 2014-05-08
Also published as: CN103795045A; CN103795045B

Abstract

Embodiments of the present invention relate to a protective apparatus. The apparatus comprises a switching device and a first isolator; one end of the switching device is connected to a negative electrode of a power supply or is connected to a positive electrode of the power supply; one of the first isolator is connected in series to the other end of the switching device; when one end of the switching device is connected to the negative electrode of the power supply, the other end of the first isolator is connected to the positive electrode of the power supply; when one end of the switching device is connected to the positive electrode of the power supply, the other end of the first isolator is connected to the negative electrode of the power supply; when a negative electrode surge voltage or current occurs on the power supply, the first isolator is on, and branches the surge current in collaboration with the switching device, so as to prevent the surge current from entering a protected device. Therefore, the protective apparatus implements the differential-mode protection on a power supply in a great magnitude, thereby improving the long wave lightning protection capability and reducing the area of a protective circuit.

Description

Description book protector

This application is submitted to the Chinese Patent Office on October 31, 2012, and the application number is

The priority of the Chinese patent application entitled "Protection Device" is hereby incorporated by reference.

Technical field

The present invention relates to the field of communications technologies, and in particular, to a protection device. Background technique

The power supply of the communication equipment is often interfered by overvoltage, which is caused by direct lightning or inductive lightning, or power frequency overvoltage and operating overvoltage generated inside the power supply system. The danger of overvoltage is too large, which directly threatens the safety of personal and communication equipment. Therefore, it is very important to protect the power supply of the communication equipment from overvoltage, so that the overvoltage is reduced to the allowable voltage range of the communication equipment. .

At present, if the power supply of the communication device is protected by a low-level differential mode, the low-level differential mode protection circuit is a primary protection circuit. Add a varistor (MOV) between the positive and negative terminals of the power supply of the communication device. If high-order differential mode protection is used, the high-order differential mode protection circuit is two-stage. protect the circuit. In addition, for larger magnitudes, power differential protection such as 10kA and above typically employs two or more levels of protection circuitry. Among them, the first-stage circuit uses a plurality of varistors in parallel.

When the power supply of the communication device is subjected to an overvoltage or an overcurrent, since the residual voltage of the first-stage varistor is usually relatively high, in order to reduce the impact on the subsequent circuit, it is necessary to add a decoupling element or circuit after the varistor. However, the decoupling element or circuit is relatively bulky. When the power supply of the communication device is subjected to lightning strikes of different polarities, the lightning protection performance of the protection circuit is greatly different due to the presence of electrolytic capacitors in the power supply circuit. When the lightning current flows from the negative pole of the power supply to the positive pole, the impact on the rear stage of the protection circuit is much more severe, mainly because the current flowing into the latter stage circuit is larger, and the latter stage circuit or device is more susceptible to damage; When the surge of the negative electrode is impacted, the current flowing through the rear stage of the protection circuit is relatively small, and the lightning protection capability in this direction is strong.

The protection circuit commonly used in the prior art is mainly used to solve short-wave lightning protection problems, such as 8/20us current wave, but for long-wave lightning protection, such as 10/350us current wave, the protection effect is poor. Summary of the invention

The embodiment of the invention provides a protection device to solve the problems of large volume, low reliability, poor long-wave lightning protection effect of the existing protection device, and the long wave protection of the protection device can be improved by using the switch and the one-way device. The lightning capability and the protection circuit area of the protection device are reduced, and the reliability of the protection device can also be improved.

In a first aspect, the present invention provides a protection device, the device comprising: a switch and a first one-way device; one end of the switch is connected to a negative pole of a power source or to a positive pole of the power source; One end of the first one-way device is connected in series with the other end of the switch; when one end of the switch is connected to a negative pole of the power source, the other end of the first one-way device is The positive pole of the power source is connected; when one end of the switch is connected to the anode of the power source, the other end of the first one-way device is connected to the negative pole of the power source; when the power source has a negative surge When the current is current, the first one-way device is turned on, and the surge current is shunted with the switch to prevent the surge current from entering the protected device.

In a first possible implementation, the device further includes: a first protector; the first protector is connected in parallel with the first one-way device; the first protector is connected in series with the switch Connecting; when the power source has a positive surge current, the first one-way device is turned off, the switch and the first protector divert the surge current to prevent the surge current from entering the Protect the device.

In a second possible implementation manner, the device further includes: a first protector; the first a protector connected in parallel with the serially connected switch and the first one-way device; when the power source has a positive surge current, the first one-way device is turned off, and the first protector splits the wave An inrush current prevents the surge current from entering the protected device.

With reference to the second possible implementation of the first aspect, in a third possible implementation, the device further includes: a second one-way device; the second one-way device is connected in series with the first protector Connecting; when the power source has a positive surge current, the first one-way device is turned off, the second one-way device is turned on, and the second one-way device and the first protector split the wave An inrush current prevents the surge current from entering the protected device.

In combination with the first to third possible implementations of the first aspect, in a fourth possible implementation, the device further includes: a decoupler; the decoupler is connected in series to the power supply Between the negative pole and the protected device, and/or connected in series between the positive pole of the power source and the protected device; the decoupler divides the voltage between the positive and negative terminals of the power source to prevent The protected device has an overvoltage.

In conjunction with the fourth possible implementation of the first aspect, in a fifth possible implementation, the device further includes: a second protector; the second protector, in parallel with the protected device, and The decoupler is connected in series; the second protector shunts a surge current generated by the power source to prevent the surge current from entering the protected device.

In combination with the first aspect or the first to fifth possible implementation manners of the first aspect, in a sixth possible implementation, the apparatus further includes: an overcurrent protector; the overcurrent protection The device is connected in series with the switch; the overcurrent protector is configured to disconnect the protection device from the power port when the protection device fails to prevent a power failure.

By applying the protection device provided by the embodiment of the present invention, the switch and the first one-way device are applied in series to the DC power source for differential mode protection. The protection device has a very low residual voltage when the surge current is impacted, and the differential mode protection of the negative pole of the power source to the positive pole is realized by using the first one-way conduction and low residual voltage characteristics; thereby realizing the difference of the power source for realizing a larger magnitude. Mode protection, not only can improve the protection device More than 40%, and reliability has also been greatly improved. DRAWINGS

1 is a schematic diagram of a protection device according to Embodiment 1 of the present invention;

2 is a circuit diagram of a protection device according to Embodiment 2 of the present invention;

3 is a circuit diagram of a protection device according to Embodiment 3 of the present invention;

4 is a schematic diagram of a protection device according to Embodiment 4 of the present invention;

FIG. 5 is a schematic diagram of a protection device according to Embodiment 5 of the present invention; FIG.

6 is a schematic diagram of a protection device according to Embodiment 6 of the present invention;

FIG. 7 is a schematic diagram of a protection device according to Embodiment 7 of the present invention;

8 is a circuit diagram of a protection device according to Embodiment 8 of the present invention;

9 is a circuit diagram of a protection device according to Embodiment 9 of the present invention;

10 is a circuit diagram of a protection device according to Embodiment 10 of the present invention;

1 is a circuit diagram of a protection device according to Embodiment 11 of the present invention;

12 is a circuit diagram of a protection device according to Embodiment 12 of the present invention;

Figure 13 is a circuit diagram of a protection device according to Embodiment 13 of the present invention;

14 is a circuit diagram of a protection device according to Embodiment 14 of the present invention;

Figure 15 is a circuit diagram of a protection device according to Embodiment 15 of the present invention;

16 is a circuit diagram of a protection device according to Embodiment 16 of the present invention;

Figure 17 is a circuit diagram of a protection device according to Embodiment 17 of the present invention;

Figure 18 is a circuit diagram of a protection device according to Embodiment 18 of the present invention.

detailed description

The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. The invention discloses a protection device, wherein a switch and a first one-way device are applied in series to a DC power supply, and the differential mode protection of the negative pole of the power source to the positive pole is realized by using the first one-way one-way conduction and low residual voltage characteristics, and the significant difference is significantly reduced. Splitting of the small after-stage circuit; using the reverse or controllable cutoff characteristic of the first one-way device The freewheeling of the switch is interrupted. The protection device circuit disclosed in the invention can effectively solve the problems of large volume, low reliability, poor long-wave lightning protection effect in the prior art, thereby realizing differential mode protection of a large-scale power supply, and not only improving the power supply Long-wave lightning protection capability, and the protection circuit area of the device can be reduced by more than 40% compared with the traditional protection circuit, and the reliability is also greatly improved.

FIG. 1 is a schematic diagram of a protection device according to a first embodiment of the present invention. As shown in the figure, the topology control device includes: a switch 11 and a first one-way device 12. Wherein, the positions of the switch 11 and the first one-way unit 12 are interchangeable. That is, one end of the switch 11 is connected to the negative pole of the power supply or to the positive pole of the power supply. The switch 11 and the first one-way unit 12 constitute a first branch.

When one end of the switch 11 is connected to the negative pole of the power source, one end of the first one-way unit 12 is connected in series with the other end of the switch 11, and the other end of the first one-way unit 12 is connected to the positive pole of the power source.

When one end of the switch 11 is connected to the positive pole of the power source, one end of the first one-way unit 12 is connected in series with the other end of the switch 11, and the other end of the first one-way unit 12 is connected to the negative pole of the power source.

When a negative surge voltage or current occurs in the power supply, the first one-way device 12 is forward-conducting, and shunt current is shunted with the switch 11 to prevent inrush current from entering the protected device.

In addition, it is to be noted that in all embodiments of the present invention, the positions of the switch 11 and the first one-way device 12 are interchangeable, and therefore, the description will not be repeated in all embodiments of the present invention.

In the protection device provided in the first embodiment of the present invention, the switch 11 used is a combination of a switch type overvoltage suppression (protection) device or a switching type overvoltage suppression (protection device). Among them, the switching device is a gas discharge tube (G s Di scharge tube, GDT) or a transient suppression thyristor (Thyr i s tor Surge Suppres sor, TSS). The first one-way device 12 is a unidirectional type device, or a combination of unidirectional type devices. Where the unidirectional device is a diode, or a metal-oxide-semiconductor

(Meta l-Oxid-Semi conductor, M0S) tube.

A specific implementation circuit of the protection device provided in Embodiment 1 of the present invention is shown in FIG. 2 and FIG. 3. In Fig. 2, the gas discharge tube and the diode D1 are connected in series. When a negative surge voltage or current occurs in the power supply, the diode D1 is forwardly turned on, and the surge current is shunted with the gas discharge tube to prevent the surge current. The stream enters the protected device. Wherein, the position of the gas discharge tube and the diode D1 can be interchanged, but the direction of the cathode and the anode of the diode D1 is unchanged, and as long as the negative surge voltage or current of the power supply is ensured, the diode D1 can be turned on.

In Fig. 3, the gas discharge tube and the MOS tube are connected in series, and the gate of the MOS tube can be controlled by the sampling control circuit. When the negative current surge current occurs in the power supply, the sampling control circuit samples the surge voltage and outputs high power. Flat, the M0S tube is opened, and the surge current is shunted with the gas discharge tube to prevent inrush current from entering the protected equipment. Among them, the position of the gas discharge tube and the MOS tube can be interchanged, and the M0S tube can be opened only when the negative surge voltage or current of the power supply is generated.

4 is a schematic diagram of a protection device according to Embodiment 4 of the present invention. As shown in the figure, the topology control device specifically includes: a switch 11, a first one-way device 12, and a first protector 13.

One end of the switch 11 is connected to the negative pole of the power source, and the other end of the switch 11 is connected to the first one-way unit 12; the switch 11 is connected in series with the first one-way unit 12; the other end of the first one-way unit 12 Connected to the positive pole of the power supply.

Wherein, the switch 11 and the first one-way device 12 form a first branch; the first protector 13 may be connected in parallel with the first one-way device 12 of the first branch, as shown in FIG. 4; or the first protection The device 13 is connected in parallel with the first branch, as shown in FIG.

The working principle of the protection device is described in detail below:

First, the first protector 13 can be connected in parallel with the first one-way 12 of the first branch.

When the power source encounters a surge voltage or current from the positive pole to the negative pole, the first one-way device 12 is turned off, and the switch 11 and the first protector 13 are protected, and the first one-way device 12 is subjected to protection. The withstand voltage of the first protector 13 in parallel with it; when the power source encounters a surge voltage or current from the negative pole to the positive pole, the first one-way device 12 is turned on, and the first one-way device 12 and the switch 11 protect effect.

Second, the first protector 13 is connected in parallel with the first branch.

When the power supply encounters a surge voltage or current from positive to negative, the first one-way device 12 is turned off, the first branch does not operate, and the first protector 13 acts as a protection; when the power supply encounters the negative pole to the positive pole When the surge voltage or current is current, the first one-way device 12 is turned on, and the first one-way device 12 and the switch device 11 are protected. Protection. The reverse resistance of the first one-way device 12 is strong, and is the breakdown voltage of the first one-way device plus the breakdown voltage of the switch.

FIG. 6 is a schematic diagram of a protection device according to Embodiment 6 of the present invention. As shown in the figure, the topology control device of the embodiment specifically includes: a switch 11, a first one-way device 12, a first protector 13 and a second one-way device 14. The first one-way device 12 and the second one-way device 14 are opposite in direction. When the first one-way device 12 is turned on, the second one-way device 14 is turned off; when the first one-way device 12 is turned off, the second one-way device 14 is turned on.

One end of the switch 11 is connected to the negative pole of the power source, the other end of the switch 11 is connected to one end of the first one-way unit 12; the switch 11 is connected in series with the first one-way unit 12; The other end is connected to the positive pole of the power supply. The switch 11 and the first one-way unit 12 form a first branch.

One end of the second one-way unit 14 is connected to the positive pole of the power source; the other end of the second one-way unit 14 is connected to the first protector 13. The second one-way unit 14 is connected in series with the first protector 13. The other end of the first protector 13 is connected to the negative electrode of the power source. The second one-way device 14 and the first protector 13 form a second branch, and the second branch is connected in parallel with the first branch. In addition, the positions of the second one-way device 14 and the first protector 13 may also be interchanged.

When the power source encounters a surge voltage or current from positive to negative, the first one-way device 12 is reversely turned off, the second one-way device 14 is conducting, and the second branch serves as a protection; When the surge voltage or current from the negative pole to the positive pole is encountered, the first one-way device 12 is forward-conducting, the second one-way device 14 is reverse-cut, and the first branch is protected.

In the protection device provided in Embodiment 4 and Embodiment 5, the switch 11 used is a switch type overvoltage suppression (protection) device, such as a Gas Di Scharge Tube (GDT), a transient state. A combination of Thyr is tor Surge Suppres sor (TSS) or a switch-type overvoltage suppression (protection) device. The first protector 13 is an overvoltage suppression (protection) device such as a combination of a M0V transistor, a Transient Voltage Suppressor (TVS) tube, or an overvoltage suppression (protection) device. The first one-way device 12 and the second one-way device 14 are unidirectional A combination of devices, or unidirectional devices. Among them, the one-way type device is a diode, or a MOS tube. Further, the first branch of the protection device provided by the first embodiment, the fourth embodiment, and the sixth embodiment further includes: an overcurrent protector. The overcurrent protector is used to disconnect the protection device from the power port when the protection device fails, thereby preventing a power failure. Taking the protection device provided in Embodiment 6 of the present invention as an example, an overcurrent protector is added to the first branch of the protection device, as shown in FIG. The overcurrent protector 15-terminal is connected to the negative pole of the power supply, and the other end is connected to one end of the switch 11; the overcurrent protector 15 is connected in series with the switch 11. The positions of the overcurrent protector 15 and the switch 11 are interchangeable.

When the first one-way device 12 fails, the switcher 11 is prevented from running free or the power supply is short-circuited or the like. In addition, in the first embodiment of the present invention, the protection device provided in the fourth embodiment and the fifth embodiment has the same function as the overcurrent protection device added to the first branch of the protection device provided by the sixth embodiment of the present invention. It will not be described in detail here. The overcurrent protector 15 may be an element or circuit having an overcurrent protection function such as a fuse or a thermistor.

The switch 11, the first one-way device 12 and the first protector 13 in the protection device provided in the fourth and fifth embodiments of the present invention constitute a first-stage protection circuit. The switch 11, the first one-way unit 12, the first protector 13 and the second one-way unit 14 in the protection device provided in the sixth embodiment of the present invention constitute a first-stage protection circuit.

Further, the first stage protection circuit of the protection device provided by the fourth embodiment, the fifth embodiment and the sixth embodiment provided by the present invention further includes a decoupler. One end of the decoupler is connected to the negative pole of the power supply, the other end of the decoupler is connected to the protected device, and the decoupler is connected in series with the protected device; or one end of the decoupler is connected to the positive pole of the power supply, The other end of the coupler is connected to the protected device, and the decoupler is connected in series with the protected device.

In addition, there may be more than one decoupler, and there may be more than one. For example, a decoupler is connected in series between the negative pole of the power supply and the protected device, and another decoupler is connected in series between the positive pole of the power supply and the protected device. In the protection device provided in the fourth embodiment of the present invention, a decoupler is added, and the serially connected decoupler and the protected device are connected in parallel with the serially connected switch and the first protector. Wherein, the function of the decoupler is: when a surge voltage or current occurs in the power supply, the surge current first flows through the series of decouplers and the protected device, and the voltage across the decoupler increases with the increase of the current intensity. Ascending, the voltage of the series connected decoupler and the protected device is also rising. When the voltage reaches the operating voltage of the first protection circuit, the first protection circuit starts to operate, and most of the current flows through the first protection circuit. Only one part of the current flows through the series of decouplers and protected devices, thus preventing most of the current from flowing through the protected device; at the same time, the decoupler is connected to the series of decouplers and the voltage across the protected device A partial voltage is applied to prevent an overvoltage condition in the protected device.

In the protection device provided in the fifth embodiment of the present invention, a decoupler is added, and the serially connected decoupler and the protected device are connected in parallel with the first protector. The function of the decoupler and the protection provided in the first embodiment of the present invention The function of adding a decoupler to the device is the same.

In addition, in the protection device provided in Embodiment 5 of the present invention, there is another method of adding a decoupler, that is, the first protector and the protected device are connected in parallel, and then the decoupler and the first protector are connected in parallel. The protection device is connected in series. When the power supply has a negative surge voltage or current, the decoupler voltage rises so that the serially connected switch and the first diode shunt the surge current to prevent the surge current from entering the protected device, which can be enhanced. The reliability of the switch action.

The protection device provided in Embodiment 6 of the present invention includes a decoupler, a parallel decoupler and a protected device, and a serially connected second diode and a first protector, the decoupler The function is the same as that of the decoupling device added to the protection device provided in the first embodiment of the present invention.

Further, the protection device provided in Embodiment 4, Embodiment 5 and Embodiment 6 further includes a second protector connected in parallel with the protected device and in series with the decoupler.

FIG. 8 is a schematic diagram of a protection device according to Embodiment 8 of the present invention. As shown, the embodiment of the present invention specifically includes: a first stage protection circuit 21 and a second protection circuit 22. The second level protection circuit 22 is composed of a decoupler 16 and a second protector 17.

The decoupler 16 has decoupling by single or multiple inductors, resistors, MOSFETs, wires, cables, etc. The components used. The second protector is an overvoltage suppression (protection) device, such as a combination of a M0V tube, a TVS tube, or an overvoltage protection device.

When the power source encounters a surge voltage or current, the second protection circuit 22 first operates, and the surge current first flows through the second protection circuit 22, and when the voltage of the second protection circuit 22 reaches the operating voltage of the first-stage protection circuit 21. When the inrush current flows through the first-stage protection circuit 21, the current flowing through the second protection circuit 22 is relatively small, so that the residual voltage of the second protection circuit 22 is low, thereby ensuring that the protected device, that is, the communication device is normal. Run or not damage. For example: the second-stage protection circuit 22 uses a weaker current-passing capability, and the TVS tube with a faster response time can also use a varistor; the first-stage circuit 21 has a strong current-passing capability and a high residual voltage. One varistor is connected in parallel. When the power supply of the communication device is subjected to a surge current, the TVS tube with a faster response time first acts, and the surge current first flows through the rear-stage TVS. When the voltage across the TVS tube and the inductor reaches the operating voltage of the varistor, Most of the inrush current flows through the varistor, and the current flowing through the post-stage circuit is small, so that the residual voltage of the TVS tube is low, ensuring that the protected communication device is operating normally or not.

It should be noted that the protection device provided by the embodiment of the present invention may be a single-stage protection device including a first-level protection circuit, or a two-level protection device including a first-level protection circuit and a second-level protection circuit, or In addition to the primary protection circuit and the secondary protection circuit, a multi-level protection device for other levels of protection circuitry is included.

According to the four different top structures provided by Embodiment 4, Embodiment 5 and Embodiment 6, a specific circuit diagram for realizing the protection device is described in detail.

First, based on the top structure provided by the fourth embodiment of the present invention.

FIG. 9 is a circuit diagram of a protection device according to Embodiment 9 of the present invention. As shown, the circuit diagram is a circuit diagram of a single-stage protection device. Specifically, the circuit diagram of the single-stage protection device includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, and a varistor M0V2. Compared with FIG. 1 , the gas discharge tube GDT is the switch 11 , the diode D1 is the first one-way device 12 , and the varistor M0V1 and the varistor M0V2 are connected in parallel as the first protector 13 . Its working principle is the same as that of Figure 4. It will not be described in detail here. FIG. 10 is a circuit diagram of a protection device according to Embodiment 10 of the present invention. As shown, the circuit diagram is a circuit diagram of a single-stage protection device using a decoupling inductor. Specifically, the circuit diagram of the single-stage protection device includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, and an inductor L. Compared with FIG. 4 , the gas discharge tube GDT is the switch 11 , the diode D1 is the first one-way device 12 , and the varistor M0V1 and the varistor M0V2 are connected in parallel as the first protector 13 . The added inductance L in the circuit diagram is a decoupler. Wherein, the function of the inductor L is: when a surge voltage or current occurs in the power source, the surge current first flows through the series connected inductor L and the protected device, and as the current intensity increases, the voltage across the inductor L rises while The series connected inductor L and the voltage of the protected device are also rising. When the voltage reaches the operating voltage of the diode D1 and the branch of the gas discharge tube GDT, the gas discharge tube GDT starts to operate, and most of the current flows through the diode D1. And the branch of the gas discharge tube GDT, only a small part of the current flows through the series connected inductor L and the protected device, thereby preventing most of the current flowing through the protected device; meanwhile, the inductance L is connected to the inductor L and is The voltage across the protection device is divided to prevent overvoltages in the protected device.

FIG. 11 is a circuit diagram of a protection device according to Embodiment 11 of the present invention. As shown, the circuit diagram is a circuit diagram of a two-stage protection device. The circuit diagram of the two-stage protection device specifically includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, an inductor L, a varistor M0V3, and a varistor M0V4. Compared with FIG. 8, the gas discharge tube GDT, the diode D1, and the varistor M0V varistor M0V2 constitute a first-stage protection circuit 21; the inductance L is a decoupler 15, a varistor MO V 3 and a varistor MO V4 Connected in parallel as a second protector 16, the inductor L, the resistor MO V 3 and the varistor M0V4 form a second stage protection circuit 22. Its working principle is the same as that of Figure 8. It will not be described in detail here.

Second, based on the topology of the present invention provided in Embodiment 5 of the present invention.

FIG. 12 is a circuit diagram of a protection device according to Embodiment 12 of the present invention. As shown, the circuit diagram is a circuit diagram of a single-stage protection device. Specifically, the circuit diagram of the single-stage protection device includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, and a varistor M0V2. Compared with FIG. 2, the gas discharge tube GDT is the switch 11, the diode D1 is the first one-way device 12, the varistor M0V1 and the pressure sensitive The resistor M0V2 is connected in parallel as the first protector 13. Its working principle is the same as that of Figure 5. No further explanation is given here.

FIG. 13 is a circuit diagram of a protection device according to Embodiment 13 of the present invention. As shown, the circuit diagram is a circuit diagram of a single-stage protection device using a decoupling inductor. The circuit diagram of the single-stage protection device specifically includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, and an inductance L. Compared with FIG. 2, the gas discharge tube GDT is the switch 11 , the diode D1 is the first one-way device 12 , and the varistor M0V1 and the varistor M0V2 are connected in parallel as the first protector 13 . Among them, the added inductance L in the circuit diagram is a decoupler. The function of the inductor L is the same as that of the inductor L in Fig. 10 and will not be described in detail herein.

Figure 14 is a circuit diagram of a protection device according to a fourteenth embodiment of the present invention. Fig. 13 is a circuit diagram of a two-stage protection circuit of the protection device according to the second embodiment of the present invention. As shown in the figure, the circuit diagram of the two-stage protection circuit includes a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, an inductor L, a varistor M0V3, and a varistor M0V4. Compared with FIG. 8, the gas discharge tube GDT, the diode D1, the varistor M0V1, and the varistor M0V2 constitute a first-stage protection circuit 21; the inductance L is a decoupler 15, a varistor MO V 3 and a varistor MO V4 is connected in parallel as a second protector 16, and the inductor L, the resistor M0V3 and the varistor M0V4 constitute a second-stage protection circuit 11. It works in the same way as Figure 8. It will not be described in detail here.

Figure 15 is a circuit diagram of a protection device according to Embodiment 15 of the present invention. This circuit diagram is another circuit diagram of a single-stage protection device using decoupling inductors. The circuit diagram of the single-stage protection device specifically includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, and an inductor L. Compared with Fig. 2, the gas discharge tube GDT is the switch 11 and the diode D1 is the first one-way unit 12, and the electric inductance is ί. The added inductance L in the circuit diagram is a decoupler. When the inductor L has a negative current surge current, the voltage of the inductor L rises, so that the gas discharge tube GDT and the diode D1 shunt the surge current, preventing the surge current from entering the protected device, and enhancing the reliability of the switch operation.

Thirdly, based on the top structure provided by the sixth embodiment of the present invention.

Figure 16 is a circuit diagram of a protection device according to a sixteenth embodiment of the present invention. As shown, the circuit The picture shows the circuit diagram of a single-stage protection device. Specifically, the circuit diagram of the single-stage protection device includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, and a diode D2. Compared with FIG. 6, the gas discharge tube GDT is the switch 11, the diode D1 is the first one-way device 12, and the varistor M0V1 and the varistor M0V2 are connected in parallel as the first protector 13. Its working principle is the same as that of Figure 5. It will not be described in detail here.

Figure 17 is a circuit diagram of a protection device according to a seventeenth embodiment of the present invention. As shown, the circuit diagram is a circuit diagram of a single-stage protection device using a decoupling inductor. The circuit diagram of the single-stage protection device specifically includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, a diode D2, and an inductor L. Compared with FIG. 6, the gas discharge tube GDT is the switch 1 1 , the diode D1 is the first one-way device 12, and the varistor M0V1 and the varistor M0V2 are connected in parallel as the first protector 13 . The added inductance L in the circuit diagram is a decoupler. The function of the inductor L is the same as that of the inductor L in Fig. 10 and will not be described in detail herein.

Figure 18 is a circuit diagram of a protection device according to Embodiment 18 of the present invention. As shown, the circuit diagram is a circuit diagram of a two-stage protection device. The circuit diagram of the two-stage protection device specifically includes: a diode D1, a gas discharge tube GDT, a varistor M0V1, a varistor M0V2, a diode D2, an inductor L, a varistor M0V3, and a varistor M0V4. Compared with FIG. 5, the gas discharge tube GDT, the diode D1, the varistor M0V1, and the varistor M0V2 constitute a first-stage protection circuit 21; the inductor L is a decoupler 15, and the varistor M0V3 and the varistor M0V4 are connected in parallel. As the second protector 16, the inductor L, the varistor M0V3 and the varistor M0V4 constitute a second-stage protection circuit 11. Its working principle is the same as that of Figure 8. It will not be described in detail here.

Therefore, the protection device provided by the embodiment of the present invention performs differential mode protection by applying the switch and the first diode in series to a DC power supply. The residual voltage of the circuit is extremely low when the surge is impacted, and the differential mode of the negative pole to the positive pole of the power supply is realized by the first one-way single-pass and low residual voltage characteristic, and the downstream circuit shunt is significantly reduced; The reverse or controllable cutoff characteristic realizes the freewheeling interruption of the discharge tube, thereby realizing the differential mode protection for the power source of a larger magnitude, not only improving the long-wave lightning protection capability of the power supply, but also protecting the circuit area of the device. With traditional protection circuits Compared with more than 40%, the reliability is also greatly improved.

In addition, the protection device provided by the embodiment of the present invention can be applied to a protection module (SPD) including the protection device, and can also be applied to a communication device or an energy device. A person skilled in the art should further appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both, in order to clearly illustrate hardware and software. Interchangeability, the composition and steps of the various examples have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be implemented in hardware, a software executed by a processor, or a combination of both. The software can be placed in random access memory (RAM), memory, read only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or technical field. Any other form of storage medium known.

The above described embodiments of the present invention are further described in detail, and the embodiments of the present invention are intended to be illustrative only. The scope of the protection, any modifications, equivalents, improvements, etc., made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

Claim CP12206

1. A protection device, characterized in that the device includes: a switch and a first one-way device; one end of the switch is connected to the negative pole of the power supply or connected to the positive pole of the power supply; the third One end of a one-way device is connected in series with the other end of the switch; when one end of the switch is connected with the negative pole of the power supply, the other end of the first one-way device is connected with the positive pole of the power supply. connected; when one end of the switch is connected to the positive pole of the power supply, the other end of the first one-way device is connected to the negative pole of the power supply;

When a negative surge voltage or current occurs in the power supply, the first one-way device is turned on and shunts the surge current with the switch to prevent the surge current from entering the protected equipment.

2. The protection device according to claim 1, characterized in that the device further includes: a first protector;

The first protector is connected in parallel with the first one-way device; the first protector is connected in series with the switch; when a positive surge voltage or current occurs in the power supply, the first one-way The switch and the first protector shunt the surge current to prevent the surge current from entering the protected equipment.

3. The protection device according to claim 1, characterized in that the device further includes: a first protector;

The first protector is connected in parallel with the series-connected switch and the first one-way device; when a positive surge voltage or current occurs in the power supply, the first one-way device is turned off, and the first one-way device is turned off. The protector shunts the surge current and prevents the surge current from entering the protected equipment.

4. The protection device according to claim 3, characterized in that the device further includes: a second one-way device;

The second one-way device is connected in series with the first protector;

When a positive surge voltage or current occurs in the power supply, the first one-way device is turned off, the second one-way device is on, and the second one-way device and the first protector divert the surge. surge current to prevent the surge current from entering the protected equipment.

5. The protection device according to any one of claims 1 to 4, characterized in that the device further includes: a decoupler;

The decoupler is connected in series between the negative pole of the power supply and the protected equipment, and/or is connected in series between the positive pole of the power supply and the protected equipment;

The decoupler divides the voltage between the positive and negative poles of the power supply to prevent overvoltage in the protected equipment.

6. The protection device according to claim 5, characterized in that the device further includes: a second protector;

The second protector is connected in parallel with the protected equipment,

The second protector shunts the surge voltage or current occurring in the power supply to prevent the surge current from entering the protected equipment.

7. The protection device according to any one of claims 1 to 6, characterized in that the device further includes: an overcurrent protector;

The overcurrent protector is connected in series with the switch;

The overcurrent protector is used to disconnect the protection device from the power port when the protection device fails to prevent power failure.

8. The protection device according to any one of claims 1 to 7, characterized in that the switch is a switching overvoltage suppression (protection) device or a combination of devices or a circuit capable of realizing the function of a switching overvoltage protection device. .

9. The protection device according to any one of claims 8, characterized in that the switching device is a gas discharge tube or a transient suppression thyristor or other switching overvoltage suppression (protection) device.

10. The protection device according to any one of claims 1 to 7, characterized in that the first one-way device or the second one-way device is a one-way device or a combination of one-way devices or has the same function. circuit.

11. The protection device according to any one of claims 10, characterized in that the unidirectional device is a diode or a metal-oxide-semiconductor MOS transistor or a device with the same characteristics.

12. The protection device according to any one of claims 1 to 7, characterized in that the first protector and the second protector are overvoltage protection devices or a combination of overvoltage protection devices.

13. The protection device according to any one of claims 12, characterized in that the overvoltage protection device is a varistor or a transient suppression diode or a device with the same characteristics.