CN217741310U - Surge protection device and surge protector - Google Patents
Surge protection device and surge protector Download PDFInfo
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- CN217741310U CN217741310U CN202220505480.7U CN202220505480U CN217741310U CN 217741310 U CN217741310 U CN 217741310U CN 202220505480 U CN202220505480 U CN 202220505480U CN 217741310 U CN217741310 U CN 217741310U
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Abstract
The utility model relates to a lightning protection field provides a surge protection device, include: the lightning protection device comprises a switch control module (102), a first lightning protection element (103) and a second lightning protection element (104), wherein the switch control module (102) is connected with a first line (101) and the first lightning protection element (103) and is used for controlling the first lightning protection element (103) to be disconnected from the first line (101) according to leakage current of the first lightning protection element (103) and controlling the second lightning protection element (104) to be connected to the first line (101); the first lightning protection element (103) and the second lightning protection element (104) are respectively connected with a ground wire (106) for discharging surge current in the first line (101). The surge protection device can prolong the time of the lightning protection effect of the SPD, thereby improving the reliability of the SPD lightning protection.
Description
Technical Field
The utility model relates to a lightning protection field especially relates to a surge protection device and surge protector.
Background
As is well known, lightning disasters are one of the most serious natural disasters, and casualties and property losses caused by the lightning disasters are countless every year in the world. For example, lightning overvoltage and lightning electromagnetic pulses cause serious damage to electrical power systems and electronic equipment. Therefore, it is particularly important to install a Surge Protector (SPD) to suppress surges and transient over-voltages on the line and to bleed over-currents on the line.
The SPD can cause leakage current to be continuously increased and the temperature to be continuously increased to cause deterioration due to lightning surge impact in the working process, and at the moment, the internal separation mechanism can enable the SPD to be tripped so that the SPD can be separated from a circuit to avoid subsequent possible fire and spontaneous combustion accidents. However, when the SPD is disconnected from the line, the protected device loses its lightning protection, exposing it to the risk of lightning strikes, and it cannot be restored to the lightning protection until a maintenance person replaces the new SPD. Therefore, how to prolong the lightning protection time of the SPD to improve the reliability of the SPD in lightning protection is a problem that needs to be solved urgently.
SUMMERY OF THE UTILITY MODEL
The utility model provides a surge protection device and surge protector, this surge protection device can prolong the time of SPD lightning protection effect in order to improve the reliability of SPD lightning protection.
In a first aspect, a surge protection device is provided, comprising: the switch control module is connected with a first line and the first lightning protection element, and is used for controlling the first lightning protection element to be disconnected from the first line according to the leakage current of the first lightning protection element (103) and controlling the second lightning protection element to be connected to the first line; the first lightning protection element and the second lightning protection element are respectively connected with a grounding wire (106) and used for discharging surge current in the first line.
The utility model provides a surge protection device is surge protector (SPD)'s core part, and it is one kind can provide thunder and lightning safety protection's device for various power electronic equipment. For example, when the first line generates a surge current due to a lightning strike, the surge current flows along the first line, passes through the switch control module, passes through the first lightning protection element, and finally flows to the ground (i.e., flows to the ground along the ground wire), so that the protected device is prevented from being damaged by the lightning strike. Since the first lightning protection element may be degraded after being subjected to lightning surge or used for a long time, the switch control module needs to detect the lightning protection effectiveness of the first lightning protection element all the time. When the switch control module detects that the leakage current of the first lightning protection element is zero or exceeds a preset threshold value, the first lightning protection element can be determined to be invalid or deteriorated, the first lightning protection element is controlled to be disconnected from the first line, and meanwhile, the second lightning protection element is controlled to be connected to the first line, so that the lightning protection of the protected device is always continuous and uninterrupted. The first lightning protection element is disconnected from the first line, and the process that the second lightning protection element is connected into the first line is automatically switched by the switch control module, so that manual participation is not needed in the whole process. Therefore, the utility model provides a surge protection device can switch over the lightning protection component automatic switching of inefficacy or degradation into new lightning protection component to make by protective apparatus be in the lightning protection all the time, thereby prolonged the time of SPD lightning protection effect and improved the reliability of SPD lightning protection simultaneously.
Optionally, the switch control module includes a detection control unit and a switch unit, and the detection control unit is sleeved on the ground wire and configured to detect a leakage current of the first lightning protection element and send a switching signal to the switch unit; the switch unit is connected with the phase line end of the first lightning protection element and used for switching the connection between the switch unit and the first lightning protection element to the second lightning protection element according to the switching signal sent by the detection control unit; the switch control module is specifically configured to: when the detection control unit detects that the leakage current of the first lightning protection element is zero or when the detection control unit detects that the leakage current of the first lightning protection element exceeds a preset threshold value, the switching signal is sent to the switch unit; and after the switching unit receives the switching signal, the switching unit disconnects the connection between the switching unit and the first lightning protection element and switches the connection between the switching unit and the second lightning protection element.
Optionally, the detection control unit includes an induction coil, and the induction coil is sleeved on the ground wire and used for detecting the leakage current of the first lightning protection element.
Optionally, the detection control unit further includes a microcontroller, and the microcontroller is configured to analyze a leakage current of the first lightning protection element detected by the induction coil, where when the microcontroller determines that the leakage current is zero or the leakage current exceeds a preset threshold, the microcontroller sends the switching signal to the switch unit.
Optionally, the switch unit includes a switch, where the switch is connected to the phase terminal of the first lightning protection element, and is configured to disconnect the connection between itself and the first lightning protection element and switch the connection between itself and the second lightning protection element according to the switching signal sent by the detection control unit.
Optionally, the first and second lightning protection elements are the same type of lightning protection element.
Optionally, the first lightning protection element includes a voltage dependent resistor, and the voltage dependent resistor is connected to the switch control module and the ground line, and is configured to discharge the surge current of the first line.
Optionally, the second lightning protection element includes a voltage dependent resistor, and the voltage dependent resistor is connected to the switch control module and the ground line, and is configured to discharge the surge current of the first line.
In a second aspect, a surge protector is provided, which is applied to a surge protection device including any one of the first aspect.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments or the prior art descriptions will be briefly described below, it is obvious that the drawings in the following descriptions are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive labor.
Fig. 1 is an application scenario of the surge protector in the embodiment of the present invention;
fig. 2 is a schematic diagram of functional modules of the surge protection device in the embodiment of the present invention;
fig. 3 is a schematic structural diagram of a surge protection device in an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a surge protection device in an embodiment of the present invention;
fig. 5 is a schematic structural diagram of a surge protector in an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments of the present invention are merely illustrative of the invention and are not intended to limit the invention. In addition, the drawings only show the parts related to the present invention, not all the structures, and therefore, the present invention is described in the following, wherein the solid black dots on the two cross lines in all the drawings indicate cross connection, and the solid black dots on the two cross lines do not indicate cross disconnection.
It should be understood that the term "and/or" as used in the specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.
Furthermore, in the description of the present invention and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.
Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present invention. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.
As is well known, surge (surge), also called surge, refers to the instantaneous occurrence of a peak value exceeding a stable value, including surge voltage and surge current. A Surge Protector (SPD) is a Device that can provide Surge safety protection for various power electronic devices, and mainly functions to limit overvoltage and discharge Surge current. Normally, the surge protector is connected in parallel with the protected device, and as shown in fig. 1, one end of the SPD is connected to the line L and the other end is grounded. When surge current and overvoltage are generated on the line L due to external interference (such as lightning stroke), the SPD can play a role in shunting and limiting voltage, so that the protected equipment is prevented from being damaged by the lightning stroke, and the working safety of the protected equipment is ensured.
The existing SPD has low lightning protection reliability, for example, when the SPD is degraded, the internal separation mechanism is tripped, so that the SPD is separated from a circuit, and further possible fire and spontaneous combustion accidents are avoided. However, when the SPD is disconnected from the line, the power electronic equipment loses the lightning protection, so that the power electronic equipment is exposed to the risk of lightning stroke, and the power electronic equipment cannot be protected from lightning again until maintenance personnel replace the new SPD. Therefore, how to prolong the time of the SPD lightning protection function to improve the reliability of the SPD lightning protection is an urgent problem to be solved.
Fig. 2 is a schematic diagram of functional modules of a surge protection device provided in an embodiment of the present invention, where the surge protection device 100 includes:
the switch control module 102 is connected with the first line 101 and the first lightning protection element 103, and is used for controlling the first lightning protection element 103 to be disconnected from the first line 101 according to leakage current of the first lightning protection element 103 and controlling the second lightning protection element 104 to be connected to the first line 101; the first lightning protection element 103 and the second lightning protection element 104 are respectively connected to the ground line 106 for discharging the surge current in the first line 101.
As an example, when the first line 101 generates an inrush current due to an external disturbance (e.g., a lightning strike or a power switching), the inrush current flows along the first line 101, first through the switch control module 102, then through the first lightning protection element 103 (i.e., the lightning protection element currently connected to the first line 101), and finally flows to the ground (i.e., flows to the ground along the ground line 106), so that the protected device is prevented from being damaged by the surge. Since the first lightning protection element 103 is easily deteriorated after being damaged by lightning or after being used for a long time, the switch control module 102 needs to constantly detect the lightning protection effectiveness of the first lightning protection element 103. When the switch control module 102 detects that the leakage current of the first lightning protection element 103 is zero, or when the switch control module 102 detects that the leakage current of the first lightning protection element 103 exceeds a preset threshold, it may be determined that the first lightning protection element 103 is out of service or degraded, and control the first lightning protection element 103 to be disconnected from the first line 101, and simultaneously control the second lightning protection element 104 (i.e., the lightning protection element to be connected to the first line 101 next time after the first lightning protection element 103 is out of service or degraded) to be connected to the first line 101, so that the lightning protection of the protected device is always continuous and uninterrupted. The disconnection of the first lightning protection element 103 from the first line 101 and the connection of the second lightning protection element 104 to the first line 101 are automatically switched by the switch control module 102, and no manual intervention is required in the whole process. Therefore, the utility model provides a surge protection device can switch into new lightning protection component with the lightning protection component automatic switching of inefficacy or degradation to make during being in lightning protection all the time by protective apparatus, thereby prolonged the time of SPD lightning protection effect and improved the reliability of SPD lightning protection simultaneously.
As an alternative example, fig. 3 shows another surge protection device provided by the embodiment of the present invention, where the first line 101 is a power line; the switch control module 102 includes a detection control unit 1021 and a switch unit 1022, wherein the detection control unit 1021 is sleeved on the ground line 106, and is configured to detect a leakage current of the first lightning protection element 103 and send a switching signal to the switch unit 1022, where the switching signal is used to instruct the switch unit 1022 to disconnect from the current lightning protection element and switch to the next lightning protection element.
For example, when the detection control unit 1021 detects that the leakage current of the first lightning protection element 103 is zero (at this time, the detection control unit 1021 determines that the first lightning protection element 103 is disabled), or when the detection control unit 1021 detects that the leakage current of the first lightning protection element 103 exceeds a preset threshold (at this time, the detection control unit 1021 determines that the first lightning protection element 103 is degraded), the detection control unit 1021 sends a switching signal to the switch unit 1022; after the switching unit 1022 receives the switching signal, the switching unit 1022 disconnects itself (i.e., the switching unit 1022) from the first lightning protection element 103 and switches to connect itself (i.e., the switching unit 1022) to the second lightning protection element (104), i.e., the switching unit 1022 disconnects the first lightning protection element 103 from the first line 101 and connects the second lightning protection element 104 to the first line 101 according to the switching signal sent by the detection control unit 1021, so that the protected device is always in lightning protection.
The detection control unit 1021 includes an induction coil, which is sleeved on the ground wire 106 and is used for detecting the leakage current of the first lightning protection element 103; as shown in fig. 3, the hollow circle in fig. 3 is used to indicate that the induction coil is sleeved on the grounding wire 106; the detection control unit 1021 further comprises a microcontroller (not shown in fig. 3) for analyzing the leakage current of the first lightning protection element 103 detected by the induction coil, wherein when the microcontroller determines that the leakage current is zero or exceeds a preset threshold, the microcontroller sends a switching signal to the switching unit 1022. The switch unit 1022 includes a switch, wherein the switch is connected to the phase terminal of the first lightning protection element 103 and is used for switching the connection between itself (i.e. the switch) and the first lightning protection element 103 to the connection between itself and the second lightning protection element 104 according to a switching signal sent by the detection control unit 1021.
For example, the detection control unit 1021 includes: the switching unit 1022 includes a switch, for example, when the microcontroller determines that the leakage current of the first lightning protection element 103 detected by the induction coil is zero, or when the microcontroller determines that the leakage current of the first lightning protection element 103 detected by the induction coil exceeds a preset threshold, it indicates that the first lightning protection element 103 is failed or deteriorated, and at this time, the microcontroller sends a switching signal to the switch; after receiving the switching signal, the switch disconnects itself (i.e., the switch) from the first lightning protection element 103 and switches itself (i.e., the switch) to the second lightning protection element 104, so that the protected device is always in lightning protection.
Optionally, the first lightning protection element 103 and the second lightning protection element 104 are the same type of lightning protection element, wherein the first lightning protection element 103 and the second lightning protection element 104 each comprise a varistor for bleeding the surge current of the first line 101. The specific type of the lightning protection element is not limited herein, as long as the lightning protection element with leakage current is within the protection scope of the present application.
For example, as shown in fig. 3, the detection control unit 1021 includes an induction coil and a microcontroller (not shown in fig. 3), the switch unit 1022 includes a switch, the first lightning protection element 103 is a first voltage dependent resistor, the second lightning protection element 104 is a second voltage dependent resistor, the switch is connected to a phase terminal of the first voltage dependent resistor (that is, the first voltage dependent resistor is connected to the first line 101 at present), and the induction coil is sleeved on the ground line 106 for detecting a leakage current of the first voltage dependent resistor; when the microcontroller judges that the leakage current of the first piezoresistor detected by the induction coil is zero or exceeds a preset threshold value, the first piezoresistor is failed or deteriorated; at the moment, the microcontroller sends a switching signal to the switch; the switch controls itself (i.e., the switch) to disconnect the first varistor from the first line 101 according to the switching signal, and controls itself (i.e., the switch) to connect the second varistor (i.e., the varistor to be connected to the first line 101 next time after the first varistor fails or deteriorates) to the first line 101. For example, when the first varistor is damaged by a lightning strike or is damaged or used for a long time, the detection control unit 1021 automatically controls the switch unit 1022 to connect the second varistor into the first line 101, so that the surge current generated by the first line 101 firstly passes through the switch unit 1022 and then the second varistor along the first line 101, and finally is discharged to the ground, thereby protecting the power electronic equipment from being damaged by the lightning strike.
Optionally, as shown in fig. 4, the surge protection device 100 includes a switch control module 102, a first lightning protection element 103, a second lightning protection element 104, and a third lightning protection element 105, where the switch control module 102 is connected to phase terminals of the first line 101 and the first lightning protection element 103, and is configured to control the first lightning protection element 103 to be disconnected from the first line 101 according to a leakage current of the first lightning protection element 103, and control the second lightning protection element 104 or the third lightning protection element 105 to be connected to the first line 101; the first lightning protection element 103, the second lightning protection element 104, and the third lightning protection element 105 are connected to a ground line 106, respectively, for discharging surge current in the first line 101. The above-mentioned first, second and third lightning protection elements 103, 104, 105 are the same type of lightning protection element, wherein the first, second and third lightning protection elements 103, 104, 105 each comprise a varistor.
For example, as shown in the surge protection device 100 shown in fig. 4, the switching control module 102 includes a detection control unit 1021 and a switching unit 1022, wherein the detection control unit 1021 includes an induction coil and a microcontroller (not shown in fig. 4), the switching unit 1022 includes a switch, the first lightning protection element 103 is a first varistor (i.e., a varistor currently connected to the first line 101), the second lightning protection element 104 is a second varistor (i.e., a varistor to be connected to the first line 101 after the first varistor fails or deteriorates), and the third lightning protection element 105 is a third varistor (i.e., a varistor to be connected to the first line 101 after the second varistor fails or deteriorates). When the microcontroller in the detection control unit 1021 determines that the first voltage dependent resistor is invalid or deteriorated (that is, the sensing coil detects that the leakage current of the first voltage dependent resistor is zero or the leakage current exceeds a preset threshold), the microcontroller sends a switching signal to the switch, and the switch disconnects the first voltage dependent resistor from the first line 101 according to the received switching signal and connects the second voltage dependent resistor to the first line 101; when the microcontroller detects that the second piezoresistor is failed or degraded (that is, the induction coil detects that the leakage current of the second piezoresistor is zero or exceeds a preset threshold), the microcontroller sends a switching signal to the switch, and the switch disconnects the second piezoresistor from the first line 101 according to the received switching signal and connects the third piezoresistor into the first line 101, so that the protected equipment is always in lightning protection.
In the surge protection device, only one lightning protection element is connected to the first line 101 at a time, and only after the current lightning protection element (for example, the first lightning protection element) in the first line 101 fails or is degraded, the next lightning protection element (for example, the second lightning protection element) is connected.
The utility model provides a surge protection device can include a plurality of the same type's lightning protection component, and among the practical application, the quantity that surge protection device contains the lightning protection component is decided by the required lightning protection grade of applied scene, and the lightning protection grade is higher, and the lightning protection component quantity that this surge protection device should contain is more. The utility model discloses only explain surge protection device with surge protection device contains two lightning protection components and three lightning protection component as an example (see fig. 3 and fig. 4), when this surge protection device contains more than three lightning protection components, its theory of operation is with the theory of operation of the surge protection device that fig. 3 and fig. 4 show, and this place is no longer repeated.
In addition, as shown in fig. 5, the present embodiment further provides a surge protector 500, and the surge protector 500 includes the surge protection device 100 described above. The surge protection device 100 has been described in detail above, and will not be described in detail here.
The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and are not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that: the technical solutions described in the foregoing embodiments can be modified or some technical features can be equivalently replaced, and the modifications or the replacements do not cause the essence of the corresponding technical solutions to depart from the spirit and the scope of the technical solutions of the embodiments of the present invention, and all should be included in the protection scope of the present invention.
Claims (9)
1. A surge protection device, comprising: a switch control module (102), a first lightning protection element (103) and a second lightning protection element (104),
the switch control module (102) is connected with a first line (101) and the first lightning protection element (103), and is used for controlling the first lightning protection element (103) to be disconnected from the first line (101) according to the leakage current of the first lightning protection element (103) and controlling the second lightning protection element (104) to be connected to the first line (101);
the first lightning protection element (103) and the second lightning protection element (104) are respectively connected with a ground wire (106) for discharging surge current in the first line (101).
2. The surge protection device according to claim 1, wherein the switch control module (102) comprises a detection control unit (1021) and a switch unit (1022),
the detection control unit (1021) is sleeved on a grounding wire (106) and is used for detecting the leakage current of the first lightning protection element (103) and sending a switching signal to the switching unit (1022);
the switch unit (1022) is connected with a phase terminal of the first lightning protection element (103) and is used for switching the connection between the switch unit and the first lightning protection element (103) to the second lightning protection element (104) according to the switching signal sent by the detection control unit (1021);
the switch control module (102) is specifically configured to: when the detection control unit (1021) detects that the leakage current of the first lightning protection element (103) is zero, or when the detection control unit (1021) detects that the leakage current of the first lightning protection element (103) exceeds a preset threshold, the switching signal is sent to the switching unit (1022); when the switching unit (1022) receives the switching signal, the switching unit (1022) disconnects itself from the first lightning protection element (103) and switches itself to the second lightning protection element (104).
3. The surge protection device of claim 2, wherein the detection control unit (1021) comprises an induction coil, and the induction coil is sleeved on a grounding wire (106) and used for detecting the leakage current of the first lightning protection element (103).
4. The surge protection device of claim 3, wherein the detection control unit (1021) further comprises a microcontroller, the microcontroller is configured to analyze a leakage current of the first lightning protection element (103) detected by the induction coil, wherein the microcontroller sends the switching signal to the switching unit (1022) when the microcontroller determines that the leakage current is zero or exceeds a preset threshold.
5. The surge protection device according to any of claims 2 to 4, wherein the switching unit (1022) comprises a diverter switch, wherein the diverter switch is connected to the phase terminals of the first lightning protection element (103) for disconnecting itself from the first lightning protection element (103) and switching itself to the connection with the second lightning protection element (104) in accordance with the switching signal sent by the detection control unit (1021).
6. The surge protection device according to any of claims 1 to 4, wherein the first lightning protection element (103) and the second lightning protection element (104) are the same type of lightning protection element.
7. The surge protection device according to any of claims 1 to 4, wherein the first lightning protection element (103) comprises a varistor connecting the switching control module (102) and a ground line (106) for bleeding surge currents of the first line (101).
8. The surge protection device according to any of claims 1 to 4, wherein the second lightning protection element (104) comprises a varistor connecting the switch control module (102) and a ground line (106) for bleeding surge current of the first line (101).
9. A surge protector is characterized in that: comprising a surge protection device according to any of claims 1 to 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220505480.7U CN217741310U (en) | 2022-03-07 | 2022-03-07 | Surge protection device and surge protector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220505480.7U CN217741310U (en) | 2022-03-07 | 2022-03-07 | Surge protection device and surge protector |
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| Publication Number | Publication Date |
|---|---|
| CN217741310U true CN217741310U (en) | 2022-11-04 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220505480.7U Active CN217741310U (en) | 2022-03-07 | 2022-03-07 | Surge protection device and surge protector |
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| Country | Link |
|---|---|
| CN (1) | CN217741310U (en) |
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- 2022-03-07 CN CN202220505480.7U patent/CN217741310U/en active Active
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