Common-mode lightning stroke protection circuit for connecting floating POE (Power Over Ethernet) equipment with grounding power supply equipment

Abstract

The utility model relates to the technical field of protection circuits, in particular to a common-mode lightning stroke protection circuit for connecting a floating POE (Power Over Ethernet) device with a grounding power supply device, which comprises a network transformer T1 used for receiving forward lightning stroke energy; the two bidirectional transient voltage suppressors TVS1 and TVS2 are used for suppressing lightning stroke energy at the initial moment; the first common mode inductor L1 is connected with the TVS1 and the TVS2 in parallel and is used for providing time delay when the current suddenly changes, so that lightning stroke interference energy is preferentially discharged through the TVS1 and the TVS2; the rectifier bridge D1 is used for enabling the lightning stroke energy discharged by the TVS1 and the TVS2 to flow to grounded PSE power supply equipment; the resistor R1 is connected behind the first common mode inductor L1 and is used for limiting the lightning stroke energy which cannot be discharged in time and then discharging the lightning stroke energy to a PSE chip; the device provided by the utility model can be applied to equipment with PSE, PD and common network ports, and has a comprehensive protection function.

Description

Technical Field

[0001] The utility model relates to the technical field of protection circuits, in particular to a common-mode lightning protection circuit for connecting a floating POE device to a grounded power supply device. Background Art

[0002] Normally, floating POE devices rely on isolation to pass common-mode lightning strikes and do not require additional common-mode lightning strike protection. However, in some application scenarios, customers will use grounded auxiliary power supply equipment to power POE devices. At this time, the topology of the environment has changed. If the common-mode lightning strike at this time is not protected, it will cause abnormal discharge of the floating device. When the lightning strike test level reaches a certain level, it will damage the entire system and cause system abnormalities.

[0003] In such an environment, we cannot rely solely on isolation, because the isolation requirements need to be very high, which cannot be achieved by some systems, and traditional network transformers cannot support such isolation requirements. In such an environment, we need to find another way. Utility Model Content

[0004] The utility model aims at the technical problems existing in the prior art and provides a common-mode lightning protection circuit for connecting a floating POE device to a grounded power supply device to solve the common-mode lightning protection problem for connecting a floating POE device to a grounded power supply device.

[0005] The technical solution of the utility model to solve the above technical problems is as follows:

[0006] A common-mode lightning protection circuit for connecting a floating POE device to a grounded power supply device is provided, the protection circuit comprising:

[0007] Network transformer T1, used to receive forward lightning energy;

[0008] Two bidirectional transient voltage suppressors TVS1 and TVS2 are used to suppress lightning energy at the initial moment;

[0009] The first common mode inductor L1 is connected in parallel with the TVS1 and TVS2 to provide a delay when the current suddenly changes, so that the lightning interference energy is discharged through the TVS1 and TVS2 first;

[0010] A rectifier bridge D1 is used to transfer the lightning energy discharged by TVS1 and TVS2 to the grounded PSE power supply equipment;

[0011] The resistor R1 is connected after the first common-mode inductor L1 and is used to limit the current of the lightning energy that cannot be discharged in time and then discharge it to the PSE chip;

[0012] A second common-mode inductor L2, which is configured to achieve the same delay effect as the first common-mode inductor L1, to ensure smooth discharge of lightning energy;

[0013] At least one differential mode transient voltage suppressor TVS3 for differential mode lightning protection;

[0014] The other two transient voltage suppressors TVS4 and TVS5 are used to further discharge the lightning energy flowing to the PSE chip to the positive and negative terminals of D1 and then to the ground wire; and

[0015] Another transient voltage suppressor TVS6 is used to discharge part of the lightning energy flowing to the PD chip to D1, and then discharged by the ground wire of the PSE grounded power supply equipment.

[0016] Furthermore, the resistance of the resistor R1 is 0.5 ohms, and the voltages of the TVS1 and TVS2 are both set to 58V.

[0017] Furthermore, the protection circuit is applied to devices with PSE and PD as well as devices with common network ports to achieve all-round protection functions.

[0018] Furthermore, the bidirectional transient voltage suppressors TVS1 and TVS2 are used to provide primary protection function, the first common mode inductor L1 and the second common mode inductor L2 have a delay function, and the transient voltage suppressors TVS4, TVS5, and TVS6 provide further protection capabilities to further reduce the residual voltage after primary protection.

[0019] Furthermore, the PSE power supply grounding device supplies power to the POE device under test, and the PSE network port performs a lightning strike test. The lightning strike energy interferes with the PSE chip, the PD chip and the 54V power supply interface, and the 54V power supply interface 2PIN is not grounded.

[0020] The beneficial effects of the utility model are:

[0021] 1. Used in special application scenarios, it can be applied to floating ground design equipment, and the floating ground equipment is connected to the grounding equipment.

[0022] 2. The utility model can be applied to devices with PSE, PD and ordinary network ports, and has comprehensive protection functions.

[0023] 3. TVS1 and TVS2 have primary protection function, L1 and L2 have delay function, TVS4, TVS5 and TVS6 have further protection capability, which can further reduce the residual pressure of primary protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A circuit diagram of the utility model;

[0025] Figure 2 This is a principle block diagram of the utility model. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the utility model, and cannot be understood as limiting the utility model. In addition, it should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0028] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0029] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are merely examples, and the purpose is not to limit the utility model. In addition, the utility model may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use scenarios of other materials.

[0030] The utility model provides the following preferred embodiments:

[0031] Embodiment 1

[0032] refer to Figure 1As shown, this embodiment provides a protection circuit for dealing with the common-mode lightning strike problem when a floating POE device is connected to a grounded power supply device, and specifically provides a detailed circuit layout and component selection. In this embodiment, the network transformer T1 is first used to receive the positive energy brought by the lightning strike, which is the key to the starting point of the protection circuit. In order to effectively suppress the lightning strike energy in the initial stage, this circuit specially selects two bidirectional transient voltage suppressors TVS1 and TVS2, and sets their protection voltage to 58V, which ensures that the excessive voltage can be effectively limited at the initial stage of the lightning strike.

[0033] Furthermore, considering the additional impact that may be caused by the current mutation, this embodiment uses a first common mode inductor L1, which is connected in parallel with TVS1 and TVS2, in order to delay the impact of the current mutation on the system, so that the lightning interference energy is preferentially discharged through TVS1 and TVS2. This configuration effectively disperses the initial lightning energy. The circuit also includes a rectifier bridge D1, which is used to receive the lightning energy after the voltage is reduced by TVS1 and TVS2, and direct it to the grounded PSE power supply device, providing a safe energy outlet for the circuit.

[0034] It should be understood that for the lightning energy that cannot be discharged in time, the R1 resistor (0.5 ohm) in this circuit plays a current limiting role. It is located after the first common mode inductor L1, and then this part of the energy can be safely transmitted to the PSE chip for subsequent discharge. In addition, the configuration of the second common mode inductor L2 is designed to achieve the same delay effect as L1 to ensure that all lightning energy can be discharged smoothly.

[0035] It is understandable that in addition to common-mode lightning protection, this circuit is also specially configured with at least one differential-mode transient voltage suppressor TVS3. Although the present invention mainly focuses on common-mode lightning, this configuration enables the circuit to have a certain degree of protection when facing differential-mode lightning. Furthermore, by adding two other transient voltage suppressors TVS4 and TVS5, this circuit ensures that the lightning energy flowing to the PSE chip can be further reduced and safely discharged through the positive and negative ends of D1 and the ground wire of the PSE grounded power supply device. At the same time, the introduction of TVS6 is to specially handle part of the lightning energy flowing to the PD chip, which is also safely discharged to the ground wire after passing through D1.

[0036] The configuration of this embodiment can not only be applied to special application scenarios, including devices with PSE, PD and ordinary network ports, but also its unique circuit design can provide all-round lightning protection for floating design devices. The reasonable configuration and design of each component enables the circuit to greatly reduce the risk of lightning strikes, protect the equipment from damage, thereby extending the service life of the equipment and ensuring the stable operation of the system. Through experimental verification on multiple devices, the effectiveness of this embodiment in solving the lightning strike problem has been proven.

[0037] Embodiment 2

[0038] According to the common-mode lightning protection circuit required when the floating POE device interfaces with the grounded power supply device as described in the previous embodiment, this embodiment focuses on the specific parameter settings of the resistor R1 and the bidirectional transient voltage suppressors TVS1 and TVS2. In this embodiment, in order to ensure the effectiveness and reliability of the circuit when handling lightning strikes, the resistor R1 is deliberately selected to be 0.5 ohms in order to achieve the current limiting effect on the lightning energy under specific conditions. This current limiting effect is particularly critical for regulating the lightning energy that cannot be discharged in the first time.

[0039] Furthermore, TVS1 and TVS2, as bidirectional transient voltage suppressors, are both set to a protection voltage of 58V. This design enables these two components to play a primary protective role in the common-mode lightning protection circuit. When subjected to a forward lightning strike, TVS1 and TVS2 act quickly to limit the overvoltage to not exceed the set threshold, thereby preventing other components in the circuit from being damaged by excessive voltage.

[0040] It should be understood that after lightning strike energy is received by the network transformer T1 as the first line of defense, this energy will be directed to the first common mode inductor L1 and TVS1, TVS2. Since the first common mode inductor L1 has the function of preventing current mutation and providing delay, this setting allows lightning strike interference energy to be discharged through TVS1 and TVS2 first. After passing through the D1 rectifier bridge, this energy will eventually flow to the grounded PSE power supply equipment.

[0041] It can be understood that by properly configuring resistors and TVS components, this embodiment provides effective common-mode lightning protection when the floating POE device is connected to the grounded power supply device to maintain the stability and safety of the entire system. According to the advantages described in the above embodiments, the protection scheme has been experimentally verified on projects such as WA7620, WA7636, WA7226, and WA6520H-HI. After implementation, it has been proved that it can effectively solve the lightning problem, protect the system from electric shock damage, and enhance the practicality and reliability of the circuit in special environments. By allowing the lightning energy to be dispersed and leaked in a safe and controllable manner, the floating design device can be fully protected even in the application scenario of connecting to the grounded power supply device.

[0042] Embodiment 3

[0043] According to the records in the above-mentioned embodiments, for the common-mode lightning protection circuit required for the interface between the floating POE device and the grounded power supply device, this embodiment specifically points out that the protection circuit can be widely used in devices with PSE and PD and devices with ordinary network ports to achieve comprehensive protection functions. This embodiment not only provides innovative solutions for special application scenarios, but also further enhances the system's lightning resistance by comprehensively considering the interface method between the floating design device and the grounded power supply device.

[0044] Furthermore, it is necessary to understand that the use of such a design can significantly improve the stability and reliability of the system in complex environments by cleverly directing the lightning energy in the circuit to a safe discharge path and utilizing the combined effects of various components in the circuit such as common-mode inductors L1 and L2, bidirectional transient voltage suppressors TVS1, TVS2, and subsequent-stage TVS elements TVS4, TVS5, and TVS6 to jointly achieve effective control and dispersion of lightning energy, thereby greatly reducing the damage to electronic equipment caused by lightning.

[0045] It can be understood that the circuit is carefully designed to not only protect the grounded power supply equipment, but also take into account the safety of the floating POE equipment connected to it, so that the entire system can operate normally without damage when facing lightning strikes.

[0046] Through the technical solution described above, it can be clearly seen that the comprehensive protection capability provided by this embodiment is not only theoretical, but also has been successfully applied and verified in projects such as WA7620, WA7636, WA7226, and WA6520H-HI, proving its effectiveness and practical application value in practice. This comprehensive protection solution can adapt to different equipment and application environments, and provides a practical and efficient solution to deal with the potential threats caused by lightning.

[0047] Through the protection design of this embodiment, the failure rate of electronic equipment caused by lightning strikes can be significantly reduced, thereby improving the overall stability and safety of the system, which has important practical significance for the field of electronic communications that requires high reliability.

[0048] Embodiment 4

[0049] According to the technical contents recorded in the above-mentioned embodiments, regarding the common-mode lightning protection circuit required when the floating POE device is connected to the grounded power supply equipment, this embodiment further clarifies the functional roles and effects of the bidirectional transient voltage suppressors TVS1, TVS2, common-mode inductors L1, L2 and other transient voltage suppressors TVS4, TVS5, TVS6 in the overall protection circuit.

[0050] In the circuit design of this embodiment, TVS1 and TVS2 serve as the front line of lightning protection, that is, the primary protection function. They quickly respond and suppress the instantaneous overvoltage caused by lightning strikes through a stable 58V protection voltage, preventing these overvoltages from flowing to subsequent circuits. L1 and L2, as primary and secondary common-mode inductors, have the function of reducing current mutations and delaying the release of energy. The setting of these two components in the circuit can ensure that in the event of a lightning strike, the voltage fluctuation can be transmitted to the next protection level in an orderly manner, rather than a disorderly and sharp jump, which can greatly help improve the control efficiency of lightning energy.

[0051] Furthermore, TVS4, TVS5 and TVS6 demonstrate their auxiliary role in the lightning protection circuit. They play a key role in the subsequent primary protection of TVS1 and TVS2, further suppressing the voltage that may remain after the primary protection, so that these residual voltages are reduced to a safe level before reaching sensitive devices such as PSE and PD chips. The use of these three components further ensures the safety and stability of the entire system when it is struck by lightning.

[0052] It is important to understand that this overall circuit design focuses on the coordinated work between components to achieve efficient control of lightning energy. Each component not only works individually, but also cooperates with each other to form a hierarchical protection network. This strategy fully utilizes the characteristics of each component and greatly improves the protection efficiency of the entire protection circuit.

[0053] Through rigorous testing and practical verification, the technical solution adopted in this embodiment is effective. By applying this embodiment, the stability and safety of floating POE equipment and grounded power supply equipment in a lightning strike environment can be significantly improved. In terms of damaging sensitive electronic components, system failures caused by lightning strikes can be effectively avoided, providing a reliable protection solution for electronic communication systems in areas with high lightning strike risks.

[0054] Embodiment 5

[0055] refer to Figure 2As shown, according to the technical solution of the common-mode lightning protection circuit between the floating POE device and the grounded power supply device recorded in the above-described embodiment, this embodiment elaborates on a method of performing a lightning test while the PSE power supply grounding device provides power to the tested POE device. In this process, the lightning energy may interfere with the PSE chip, PD chip and 54V power interface, and the 54V power interface adopts a 2PIN ungrounded design, thereby avoiding the problems caused by direct grounding.

[0056] Furthermore, this embodiment ensures that even in the event of a lightning strike, the lightning energy can be effectively controlled and distributed to protect the equipment from damage through a certain circuit design. First, the forward lightning energy passes through the network transformer T1 and flows to the common-mode inductor L1 and transient voltage suppressors TVS1 and TVS2 at the same time. As a common-mode inductor, L1 has the function of preventing current mutation and delay. Its purpose is to allow the lightning interference energy to be first suppressed by TVS1 and TVS2. Secondly, the common-mode inductor L2 has a similar function, ensuring that the lightning energy can be smoothly discharged into the grounded PSE power supply equipment, thereby ensuring the safety of the PSE chip.

[0057] It should be understood that in the lightning protection scheme of the present invention, special attention is paid to the priority and orderly control of lightning energy. In addition to the functions of TVS1, TVS2, L1 and L2 mentioned above, the R1 resistor and further transient voltage suppressors TVS4, TVS5 and TVS6 are also involved. These components work together to effectively shunt and reduce the impact of lightning energy on PSE and PD chips, ultimately achieving efficient protection of the circuit.

[0058] The technical solution described in this embodiment has been proven to be effective in the verification of projects such as WA7620, WA7636, WA7226, and WA6520H-HI. It can not only adapt to special application scenarios and protect floating ground devices to safely connect to grounded devices, but also provide all-round protection functions for devices with PSE, PD, and ordinary network ports. In addition, by further reducing the residual voltage after primary protection, this embodiment significantly improves the efficiency and reliability of the entire protection system.

[0059] Through the application of this embodiment, the survivability of electronic communication equipment in the face of lightning challenges can be significantly enhanced, thereby ensuring the stable operation and long-term reliability of the system. This is especially important for electronic equipment in areas with high lightning activity, providing a practical means of protection for them.

[0060] The beneficial effects of the present invention are specifically embodied in that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A common mode lightning protection circuit for connecting a floating POE device to a grounded power supply device, characterized in that: The protection circuit comprises: Network transformer (T1), used to receive forward lightning energy; Two bidirectional transient voltage suppressors (TVS1, TVS2) are used to suppress the lightning energy at the initial moment; A first common mode inductor (L1) is connected in parallel with the TVS1 and TVS2 and is used to provide a delay when the current suddenly changes, so that the lightning interference energy is discharged through the TVS1 and TVS2 first; A rectifier bridge (D1) is used to transfer the lightning energy discharged by TVS1 and TVS2 to the grounded PSE power supply equipment; A resistor (R1), connected after the first common-mode inductor (L1), is used to limit the current of lightning energy that cannot be discharged in time and subsequently discharge it to the PSE chip; A second common-mode inductor (L2) is configured to achieve the same delay effect as the first common-mode inductor (L1) to ensure smooth discharge of lightning energy; At least one differential mode transient voltage suppressor (TVS3) for differential mode lightning protection; The other two transient voltage suppressors (TVS4 and TVS5) are used to further discharge the lightning energy flowing to the PSE chip to the positive and negative terminals of D1 and then to the ground wire; and Another transient voltage suppressor (TVS6) is used to discharge part of the lightning energy flowing to the PD chip to D1, and then discharged by the ground wire of the PSE grounded power supply equipment.

2. The common mode lightning protection circuit for connecting a floating POE device to a grounded power supply device according to claim 1, characterized in that: The resistance of the resistor (R1) is 0.5 ohms, and the voltages of TVS1 and TVS2 are both set to 58V.

3. The common mode lightning protection circuit for connecting a floating POE device to a grounded power supply device according to claim 1, characterized in that: The protection circuit is applied to equipment with PSE and PD and equipment with common network ports to achieve all-round protection functions.

4. The common mode lightning protection circuit for connecting a floating POE device to a grounded power supply device according to claim 1, characterized in that: The bidirectional transient voltage suppressor (TVS1, TVS2) is used to provide a primary protection function, the first common-mode inductor (L1) and the second common-mode inductor (L2) have a delay function, and the transient voltage suppressor (TVS4, TVS5, TVS6) provides further protection capabilities to further reduce the residual voltage after the primary protection.

5. The common mode lightning protection circuit for connecting a floating POE device to a grounded power supply device according to claim 1, characterized in that: The PSE grounded power supply device supplies power to the POE device under test, and the PSE network port performs a lightning strike test. The lightning strike energy interferes with the PSE chip, the PD chip and the 54V power supply interface, and the 54V power supply interface 2PIN is not grounded.

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