PoE injector network lightning protection device

Abstract

The invention discloses a PoE injector network lightning protection device, which is connected between a network port and an internal circuit, and comprises an isolation network transformer, the input end of the isolation network transformer is connected with the network port, and the output end of the isolation network transformer is connected with the internal circuit; the discharge module is connected with the input end of the isolation network transformer; the clamping module is connected with the input end and the output end of the isolation network transformer; the input end of the isolation rectification module is connected with the output end of the isolation network transformer; and the low-impedance grounding system is connected with the grounding ends of the discharge module, the clamping module and the isolation rectification module. Through the multi-stage collaborative design of the isolation network transformer, the discharge module, the clamping module, the isolation rectification module and the low-impedance grounding system, a complete protection chain of step-by-step pressure relief and energy suppression is formed.

Description

Technical Field

[0001] The invention belongs to the technical field of network lightning protection and relates to a PoE injector network lightning protection device. Background Art

[0002] In a 10kV high-voltage network environment, the lightning protection design of the PoE injector is crucial to the reliability of the equipment. In the prior art, the lightning protection scheme of the network port usually uses a single gas discharge tube or transient suppression diode for protection. This type of design has significant defects: the gas discharge tube has insufficient discharge capacity, resulting in the inability to quickly discharge the large current of the lightning strike, and the residual voltage is easy to break down the back-end circuit; at the same time, the coordinated suppression capability of common-mode and differential-mode surges is weak, and there is a lack of choke design for the center tap of the signal line. The surge energy is coupled to the internal circuit through parasitic capacitance, causing signal degradation. In addition, the impedance of the traditional grounding system is high, and the isolation network transformer is only used for signal isolation, and does not form a multi-level discharge path with the lightning protection module, resulting in an increased risk of lightning energy retention. Especially in outdoor long-distance transmission scenarios, the above problems are further amplified, seriously threatening the stability of the PoE injector and the powered equipment. Summary of the invention

[0003] The present invention provides a PoE injector network lightning protection device, which realizes the step-by-step discharge of lightning energy and the blocking of the conduction path through a multi-stage collaborative protection design of an isolation network transformer, a discharge module, a clamping module, an isolation rectifier module and a low-impedance grounding system.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A PoE injector network lightning protection device, connected between a network port and an internal circuit, comprising: An isolation network transformer, wherein an input end of the isolation network transformer is connected to the network port, and an output end of the isolation network transformer is connected to the internal circuit; A discharge module, the discharge module is connected to the input end of the isolation network transformer; A clamping module, the clamping module is connected to an input end and an output end of the isolation network transformer; An isolation rectifier module, the input end of the isolation rectifier module is connected to the output end of the isolation network transformer; A low-impedance grounding system is connected to the grounding terminals of the discharge module, the clamping module and the isolation rectifier module.

[0005] Furthermore, the discharge module includes a plurality of gas discharge tubes; The first end and the second end of each gas discharge tube are respectively connected across each group of differential signal lines at the input end of the isolation network transformer; The third end of each of the gas discharge tubes is connected to the low impedance grounding system.

[0006] Furthermore, the breakdown voltage of the gas discharge tube is 90V, and the maximum pulse current is 20kA.

[0007] Furthermore, the clamping module further includes: A choke coil, each group of differential signal lines of the isolation network transformer is provided with a center tap, and the choke coil is connected to the center tap; A first clamping element and a first varistor are connected in parallel and then connected in series between the output end of the isolation network transformer and the low-impedance grounding system.

[0008] Furthermore, the center tap includes a primary center tap and a secondary center tap, the primary center tap is provided at the primary winding of the network transformer, and the secondary center tap is provided at the secondary winding of the network transformer; The choke coil is connected across the primary center tap and the secondary center tap of the differential signal line of the isolation network transformer.

[0009] Furthermore, the isolation rectifier module includes: A fast recovery diode bridge, wherein the input end of the fast recovery diode bridge is connected to the center tap of the output end of the isolation transformer; A clamping component, one end of which is connected to the positive DC output end of the fast recovery diode bridge, and the other end of which is connected to the negative DC output end of the fast recovery diode bridge and the low impedance grounding system; A pressure-sensitive component is connected in parallel with the fast recovery diode bridge, one end of the pressure-sensitive component is connected to the AC input end of the fast recovery diode bridge, and the other end of the pressure-sensitive component is connected to the low-impedance grounding system.

[0010] Further, the clamp assembly includes a second clamp, a third clamp and a fourth clamp; One end of the second clamp is connected to the positive DC output end of the fast recovery diode bridge, and the other end of the second clamp is connected to the low impedance grounding system; One end of the third clamp is connected to the positive DC output end of the fast recovery diode bridge, and the other end of the third clamp is connected to the negative DC output end of the fast recovery diode bridge; One end of the fourth clamp is connected to the negative DC output end of the fast recovery diode bridge, and the other end of the fourth clamp is connected to the low impedance grounding system.

[0011] Furthermore, the clamping voltage values ​​of the first clamp, the second clamp, the third clamp, and the fourth clamp are 58V.

[0012] Beneficial effects of the present invention: This application forms a complete protection chain of step-by-step pressure relief and energy suppression through a multi-level collaborative design of an isolation network transformer, a discharge module, a clamping module, an isolation rectifier module and a low-impedance grounding system. The isolation network transformer blocks the surge conduction path through physical isolation, while retaining the signal transmission channel to ensure the independence of data and power transmission; the discharge module, as the first level of protection, quickly discharges the large current energy generated by lightning strikes, significantly reducing the impact on the front-end circuit; the clamping module, as the second level of protection, accurately suppresses the residual surge voltage after isolation to avoid overvoltage damage to the back-end sensitive circuit; the isolation rectifier module further blocks the surge energy from being transmitted to the powered equipment, and maintains the integrity of the signal waveform through the rectification process to ensure the data transmission rate and power supply stability; the low-impedance grounding system efficiently conducts lightning current through a unified discharge path to eliminate internal circuit coupling interference. Each module attenuates the lightning strike energy step by step with the collaborative mechanism of "isolation-discharge-clamp-blocking", which not only improves the safety of the equipment under high-voltage surge impact, but also solves the problems of signal degradation and grounding failure in traditional solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0014] Figure 2 It is a schematic diagram of the circuit structure of the present invention. DETAILED DESCRIPTION

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of the present invention or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0016] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In a 10kV high-voltage network environment, the equipment needs to ensure the stability of both power supply and data communication. Traditional protection solutions cannot effectively cope with high-energy surges generated by lightning strikes due to their single structure and insufficient discharge capacity, resulting in frequent equipment damage and signal interruption problems. To this end, the present invention proposes a technical solution that integrates a multi-level protection and isolation mechanism to improve the equipment's ability to resist lightning strikes through collaborative design.

[0019] The present invention provides Figures 1-2 In an embodiment of the present invention, a PoE injector network lightning protection device is connected between a network port and an internal circuit, comprising: An isolation network transformer, wherein an input end of the isolation network transformer is connected to the network port, and an output end of the isolation network transformer is connected to the internal circuit; A discharge module, the discharge module is connected to the input end of the isolation network transformer; A clamping module, the clamping module is connected to an input end and an output end of the isolation network transformer; An isolation rectifier module, the input end of the isolation rectifier module is connected to the output end of the isolation network transformer; A low-impedance grounding system is connected to the grounding terminals of the discharge module, the clamping module and the isolation rectifier module.

[0020] Specifically, the present invention realizes the stable operation of the PoE injector in a high-voltage lightning strike environment through a multi-level collaborative protection architecture. The device includes an isolation network transformer, a discharge module, a voltage clamping module, an isolation rectifier module and a low-impedance grounding system, and each module works together to form a step-by-step energy attenuation mechanism. The input end of the isolation network transformer is connected to the external network, and its multiple groups of differential signal pairs are physically isolated through independent windings. The output end is connected to the internal circuit, and the surge conduction path is blocked by magnetic circuit isolation, while retaining the signal transmission channel. As the first layer of protection, the discharge module is arranged between each group of differential signal pairs at the input end. When the surge voltage exceeds the threshold, the discharge channel is quickly turned on, and the high current energy is directly discharged to the low-impedance grounding system, which significantly reduces the impact on the front-end circuit.

[0021] As the second layer of protection, the clamping module is configured at the output end of the isolation network transformer and connected in parallel between the output node of the isolation transmission unit and the grounding system. The response time of its suppression element is less than 1 nanosecond, which accurately limits the residual surge voltage to a safe range and avoids overvoltage damage to the sensitive circuits at the back end. The isolation rectifier module further converts the isolated AC signal into a DC output. It integrates energy blocking components to block the conduction of surge residual energy to the powered equipment. The signal waveform integrity is maintained throughout the rectification process to ensure that the data transmission rate is stable at the gigabit level and the power supply voltage fluctuation is controlled within 3%. The low-impedance grounding system adopts a ring grounding structure with a grounding resistance of less than 1 ohm, providing a unified low-impedance discharge path for all modules. The discharge path is independent of the internal circuit of the equipment, completely eliminating the coupling interference of lightning current on sensitive components.

[0022] The beneficial effect of the present invention is that through the systematic design of physical isolation, step-by-step discharge, fast clamping and low-impedance grounding, efficient attenuation and diversion of lightning energy is achieved. The synergistic effect of the multi-level protection mechanism not only ensures the safety of the equipment under 10kV high-voltage surge impact, but also ensures the stability of gigabit data transmission and power supply reliability. The ring grounding system and modular design significantly improve the adaptability of outdoor long-distance and complex industrial scenes.

[0023] The discharge module includes a plurality of gas discharge tubes; The first end and the second end of each gas discharge tube are respectively connected across each group of differential signal lines at the input end of the isolation network transformer; The third end of each of the gas discharge tubes is connected to the low impedance grounding system.

[0024] Specifically, as shown in the attached figure, the input end of the isolation network transformer (i.e., the primary winding side) is provided with four groups of differential signal lines, namely the first group (TD1+ / TD1-), the second group (RD1+ / RD1-), the third group (TD2+ / TD2-), and the fourth group (RD2+ / RD2-). A gas discharge tube (GDT) is connected across each group of differential signal lines, specifically: The gas discharge tube GDT1 is connected between TD1+ and TD1-; The gas discharge tube GDT2 is connected between RD1+ and RD1-; The gas discharge tube GDT3 is connected between TD2+ and TD2-; The gas discharge tube GDT4 is connected between RD2+ and RD2-.

[0025] The third terminal of each gas discharge tube GDT is connected to the ring grounding grid (grounding resistance ≤ 1Ω) through a low-impedance grounding path.

[0026] The working process is as follows: in the lightning surge scenario, the lightning energy enters the network port of the PoE injector through the network cable and acts on the differential signal lines (such as TD1+ and TD1-). When the line voltage exceeds 90V, the gas discharge tube GDT1 breaks down within 100ns to form a low-impedance path. The surge current (above 10kA) is directly discharged to the ring grounding grid through the third end of the gas discharge tube GDT1 to prevent the current from flowing through the back-end circuit. After the gas discharge tube is discharged, the residual voltage between the lines is limited to less than 500V, providing buffering for subsequent protection modules (such as clamping modules and isolation rectifier modules). The rapid discharge of the gas discharge tube reduces the voltage impact on the differential signal pair.

[0027] In this embodiment, the gas discharge tube (GDT) is connected across each group of differential signal lines at the input end of the isolation network transformer (such as TD1+ / TD1-, RD1+ / RD1-, etc.), and the third end of each group of GDTs is connected to the low-impedance grounding system through an independent wire. With this design, when a lightning surge invades the network port, the GDT can respond quickly and discharge the surge energy between the lines to the ground through the grounding path, avoiding differential mode overvoltage from damaging the back-end circuit. At the same time, the symmetrical layout of multiple groups of GDTs ensures balanced protection of each differential line pair and reduces signal transmission interference. Combined with the low impedance characteristics of the grounding system, the lightning current is efficiently conducted away from the inside of the device, significantly improving the reliability of the PoE injector in a high-voltage lightning environment.

[0028] The breakdown voltage of the gas discharge tube is 90V, and the maximum pulse current is 20kA.

[0029] Specifically, the breakdown voltage of the gas discharge tube is set to 90V, and the design of the maximum pulse current of 20kA is mainly based on the comprehensive adaptation of the characteristics of the PoE power supply environment and the requirements of lightning surge protection. The normal operating voltage range of the network port under the PoE power supply standard is usually 44-57V. The breakdown voltage is set to 90V to ensure that the gas discharge tube will not malfunction when the power supply voltage fluctuates instantaneously (such as the peak voltage ≤80V), avoiding normal power supply interruption; at the same time, this voltage value is lower than the minimum withstand voltage (usually ≥200V) of the back-end circuit components (such as PHY chips or power modules), so that the overvoltage generated by lightning strikes preferentially triggers the gas discharge tube to discharge energy rather than directly impacting sensitive components. The setting of the maximum pulse current of 20kA is aimed at the extreme surge energy that may occur in the direct lightning strike scenario of the 10kV high-voltage network, meeting the requirements of IEC 61643-21 for the current carrying capacity of the first-level protection device (Imax≥20kA), ensuring that the surge current can be completely discharged in a single lightning strike. In addition, this parameter design has been verified by 10 times of 10kA surge impact test under the IEC 61000-4-5 standard. The breakdown voltage drift of the gas discharge tube after continuous discharge is ≤3%, without physical deformation or performance degradation, ensuring the long-term reliability of equipment under repeated lightning strikes in outdoor long-distance transmission scenarios (such as smart street lights and wireless base stations).

[0030] The clamping module comprises: A choke coil, each group of differential signal lines of the isolation network transformer is provided with a center tap, and the choke coil is connected to the center tap; A first clamping element TVS1 and a first varistor MOV1 are connected in parallel between the output end of the isolation network transformer and the low-impedance grounding system.

[0031] Specifically, the clamping component is a transient suppression diode TVS, and there are choke coils LF1 and LF2 in the drawings of the specification of the present application. This embodiment mainly describes the choke coil LF1, and the connection relationship and working process of the choke coil LF2 are the same as those of the choke coil LF1.

[0032] More specifically, the center tap includes a primary center tap and a secondary center tap, the primary center tap is provided at the primary winding of the network transformer, and the secondary center tap is provided at the secondary winding of the network transformer; The choke coil is connected across the primary center tap and the secondary center tap of the differential signal line of the isolation network transformer.

[0033] As shown in the accompanying drawings, in the embodiment of the present application, the center taps of the primary winding on the left side of the isolation network transformer include CT1, CT2, CT3, and CT4, and the center taps of the secondary winding on the right side include CT5, CT6, CT7, and CT8. The primary center taps are located at the physical midpoint of the primary winding of the isolation network transformer. For example, the primary center tap of the first group of differential lines (TD1+ / TD1-) is CT1, and the primary center tap of the second group of differential lines (RD1+ / RD1-) is CT2; the secondary center tap The tap is located at the physical midpoint of the secondary winding. For example, the secondary center tap corresponding to the first group of differential lines is CT8, and the secondary center tap corresponding to the second group of differential lines is CT7. Each primary center tap (CT1, CT2, etc.) is bridged to the corresponding secondary center tap (CT8, CT7, etc.) through an independent choke coil (such as LF1, LF2). For example, the first winding of LF1 connects CT1 (primary) and CT8 (secondary), and the second winding of LF1 connects CT2 (primary) and CT7 (secondary).

[0034] The first winding of the choke coil LF1 is connected to the primary center tap CT1 and the secondary center tap CT8, and the second winding is connected to the primary center tap CT2 and the secondary center tap CT7, so as to suppress common-mode interference, filter out the common-mode noise of the center tap, and ensure the symmetry of the differential signal (such as TD1+ / TD1-, RD1+ / RD1-). The choke coil LF2 is configured according to the number of differential line groups, for example, connecting other center tap pairs (such as CT3-CT6, CT4-CT5); the first clamping component TVS1 and the first varistor MOV1 are connected in parallel, the output node of the choke coil LF1 (that is, the common-mode reference level node after filtering) is connected to one end of the first clamping component TVS1, and the other end of the first clamping component TVS1 is connected in parallel to the first varistor MOV1, and they are connected to the common ground (PE) together. The first clamping component TVS1 and the first varistor MOV1 are connected in parallel mainly to perform overvoltage clamping protection on the signal node after filtering of the choke coil LF1. The connection method of the choke coil LF2, and the TVS11 and MOV11 connected to the choke coil LF2 is the same as that of the above embodiment.

[0035] More specifically, the inductance of the choke coil is greater than or equal to 220μH, which is used to suppress common mode interference in the 20kHz-100MHz frequency band and is compatible with the PoE signal bandwidth (≤250MHz). The clamping voltage of the first clamp TVS1 is 58V, which is adapted to the maximum withstand voltage of the powered equipment (60V), and the response time is less than 1ns. The nominal voltage of the first varistor MOV1 is 75V, and the current capacity is 5kA (8 / 20μs waveform), which shares energy together with the first clamp TVS1.

[0036] Furthermore, in this embodiment, when common-mode noise is coupled to the center tap (such as CT1, CT8) through the shielding layer or parasitic capacitance, the choke coil LF1 offsets the common-mode current through magnetic coupling, forcing the energy to be transferred to the common-mode reference node. When the voltage at the common-mode reference node exceeds the safety threshold (58V), the first clamping component TVS1 and the first varistor MOV1 are quickly turned on (the response time is less than 10ns), and the energy is discharged to the common ground, and the suppression efficiency is greater than 90%; the symmetrical winding design of the choke coil ensures the symmetry of the transmission of differential signals (such as TD1+ / TD1-), reduces the signal distortion caused by common-mode interference, and the low clamping voltage (58V) of the first clamping component TVS1 prevents the differential mode residual voltage from exceeding the tolerance range of the back-end circuit, ensuring the bit error rate at a transmission rate of 1Gbps. The parallel design of the first clamping component TVS1 and the first varistor MOV1 provides a dual clamping path, the first varistor MOV1 shares the large current surge, and the first clamping component TVS1 achieves fast voltage clamping to avoid the risk of single point failure.

[0037] The isolated rectifier module comprises: A fast recovery diode bridge, wherein the input end of the fast recovery diode bridge is connected to the center tap of the output end of the isolation transformer; A clamping component, one end of which is connected to the positive DC output end of the fast recovery diode bridge, and the other end of which is connected to the negative DC output end of the fast recovery diode bridge and the low impedance grounding system; A pressure-sensitive component is connected in parallel with the fast recovery diode bridge, one end of the pressure-sensitive component is connected to the AC input end of the fast recovery diode bridge, and the other end of the pressure-sensitive component is connected to the low-impedance grounding system.

[0038] Specifically, as shown in the accompanying drawings, there are at least two fast recovery diode bridges in the present application, and the AC input end of the fast recovery diode bridge is connected to the center tap of the secondary side of the isolation network transformer (such as CT5, CT6, CT7, CT8). Specifically, the AC input end of the first fast recovery diode bridge is connected to CT5 (RX2+secondary side midpoint) and CT6 (TX2+secondary side midpoint), and the AC input end of the second fast recovery diode bridge is connected to CT7 (RX1+secondary side midpoint) and CT8 (TX1+secondary side midpoint). The clamping component is connected as a whole between the positive DC output end and the negative DC output end of the fast recovery diode bridge, and its function is to perform voltage clamping on the differential mode surge at the DC output end. The varistor component includes a second varistor component MOV2 and a third varistor component MOV3. One end of the second varistor component MOV2 or the third varistor component MOV3 is connected to the AC input end of the fast recovery diode bridge (such as between CT5 and CT6), and the other end is connected to the low impedance grounding system (PE).

[0039] More specifically, during normal operation, the fast recovery diode bridge rectifies the AC signal at the center tap of the secondary side into DC to supply power to the powered equipment. When a lightning surge invades, the high reverse withstand voltage (≥600V) of the diode bridge blocks the surge current from being transmitted to the DC output terminal. The varistor discharges the differential mode surge energy at the AC input terminal (CT5-CT6) to the grounding system with a current of 5kA. The clamping component limits the differential mode residual voltage between the positive and negative electrodes to below 58V to avoid overvoltage damage to the back-end circuit. The short reverse recovery time of the fast recovery diode reduces signal waveform distortion and ensures the bit error rate at a transmission rate of 1Gbps.

[0040] The clamp assembly includes a second clamp member TVS2, a third clamp member TVS3 and a fourth clamp member TVS4; One end of the second clamping element TVS2 is connected to the positive DC output end of the fast recovery diode bridge, and the other end of the second clamping element TVS2 is connected to the low impedance grounding system; One end of the third clamp TVS3 is connected to the positive DC output end of the fast recovery diode bridge, and the other end of the third clamp TVS3 is connected to the negative DC output end of the fast recovery diode bridge; One end of the fourth clamping component TVS4 is connected to the negative DC output end of the fast recovery diode bridge, and the other end of the fourth clamping component TVS4 is connected to the low impedance grounding system.

[0041] The clamping voltage value of the first clamp, the second clamp TVS2, the third clamp TVS3, and the fourth clamp TVS4 is 58V.

[0042] Specifically, the second clamping member TVS2 is connected between the positive DC output terminal (V+) of the fast recovery diode bridge and the common ground (PE), clamping the positive voltage to ground; The third clamp TVS3 is connected between the positive DC output terminal (V+) and the negative DC output terminal (V-) to suppress the differential mode surge between the positive and negative electrodes; The fourth clamping element TVS4 is connected between the negative DC output terminal (V-) and the common ground (PE) to clamp the negative voltage to ground; The varistor is connected in parallel at the AC input end of the fast recovery diode bridge (such as between CT5 and CT6), and the other end is connected to the common ground (PE) to discharge differential mode surge energy.

[0043] More specifically, when a differential-mode surge (such as overvoltage between the positive and negative poles) invades the DC output terminal, the third clamp TVS3 is turned on first to clamp the voltage to below 58V to prevent overvoltage damage to the back-end circuit; the varistor simultaneously discharges the differential-mode energy (5kA) of the AC input terminal to reduce the impact on the diode bridge. When the positive or negative pole-to-ground voltage exceeds 58V, the second clamp TVS2 or the fourth clamp TVS4 is quickly turned on to discharge the energy to the grounding system. The residual pressure is ≤60V. Combined with low-impedance grounding (≤1Ω), the common-mode current is efficiently conducted away from the equipment. The low clamping voltage (58V) of the clamp avoids power supply voltage fluctuations and ensures stable operation of the powered equipment. The short reverse recovery time of the fast recovery diode reduces signal distortion.

[0044] The invention is operational with numerous general purpose or special purpose computer system environments or configurations.

[0045] For example: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics devices, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, etc.

[0046] The invention may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer.

[0047] Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network.

[0048] In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.

[0049] Specifically, a person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through computer-readable instructions, and the computer-readable instructions can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the aforementioned storage medium can be a non-volatile storage medium such as a disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

[0050] It should be understood that although the steps in the flowchart of the accompanying drawings are shown in sequence according to the instructions of the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise clearly stated in this document, the execution of these steps is not strictly limited in order and can be performed in other orders.

[0051] Moreover, at least part of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The order of execution is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0052] Obviously, the embodiments described above are only some embodiments of the present invention, rather than all embodiments. The drawings provide preferred embodiments of the present invention, but do not limit the scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0053] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned specific embodiments, or replace some of the technical features therein with equivalents. Any equivalent structure made using the contents of the present invention's specification and drawings, directly or indirectly applied to other related technical fields, is also within the scope of patent protection of the present invention.

Claims

1. A PoE injector network lightning protection device, connected between a network port and an internal circuit, characterized in that: include: An isolation network transformer, wherein an input end of the isolation network transformer is connected to the network port, and an output end of the isolation network transformer is connected to the internal circuit; A discharge module, the discharge module is connected to the input end of the isolation network transformer; A clamping module, the clamping module is connected to an input end and an output end of the isolation network transformer; An isolation rectifier module, the input end of the isolation rectifier module is connected to the output end of the isolation network transformer; A low-impedance grounding system is connected to the grounding terminals of the discharge module, the clamping module and the isolation rectifier module.

2. A PoE injector network lightning protection device according to claim 1, characterized in that: The discharge module includes a plurality of gas discharge tubes; The first end and the second end of each gas discharge tube are respectively connected across each group of differential signal lines at the input end of the isolation network transformer; The third end of each of the gas discharge tubes is connected to the low impedance grounding system.

3. A PoE injector network lightning protection device according to claim 2, characterized in that: The breakdown voltage of the gas discharge tube is 90V, and the maximum pulse current is 20kA.

4. A PoE injector network lightning protection device according to claim 1, characterized in that: The clamping module further comprises: A choke coil, each group of differential signal lines of the isolation network transformer is provided with a center tap, and the choke coil is connected to the center tap; A first clamping element and a first varistor are connected in parallel and then connected in series between the output end of the isolation network transformer and the low-impedance grounding system.

5. A PoE injector network lightning protection device according to claim 4, characterized in that: The center tap includes a primary center tap and a secondary center tap, the primary center tap is arranged on the primary winding of the network transformer, and the secondary center tap is arranged on the secondary winding of the network transformer; The choke coil is connected across the primary center tap and the secondary center tap of the differential signal line of the isolation network transformer.

6. A PoE injector network lightning protection device according to claim 4, characterized in that: The isolated rectifier module comprises: A fast recovery diode bridge, wherein the input end of the fast recovery diode bridge is connected to the center tap of the output end of the isolation transformer; A clamping component, one end of which is connected to the positive DC output end of the fast recovery diode bridge, and the other end of which is connected to the negative DC output end of the fast recovery diode bridge and the low impedance grounding system; A pressure-sensitive component is connected in parallel with the fast recovery diode bridge, one end of the pressure-sensitive component is connected to the AC input end of the fast recovery diode bridge, and the other end of the pressure-sensitive component is connected to the low-impedance grounding system.

7. A PoE injector network lightning protection device according to claim 6, characterized in that: The clamp assembly includes a second clamp, a third clamp and a fourth clamp; One end of the second clamp is connected to the positive DC output end of the fast recovery diode bridge, and the other end of the second clamp is connected to the low impedance grounding system; One end of the third clamp is connected to the positive DC output end of the fast recovery diode bridge, and the other end of the third clamp is connected to the negative DC output end of the fast recovery diode bridge; One end of the fourth clamp is connected to the negative DC output end of the fast recovery diode bridge, and the other end of the fourth clamp is connected to the low impedance grounding system.

8. A PoE injector network lightning protection device according to claim 7, characterized in that: The clamping voltage value of the first clamp, the second clamp, the third clamp, and the fourth clamp is 58V.

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