Surge protection circuit, power supply equipment and Ethernet power supply system

Abstract

The invention relates to the technical field of surge protection, and discloses a surge protection circuit, power supply equipment and an Ethernet power supply system, and the protection circuit comprises a first Ethernet interface, a first transformer, a second transformer, a first protection module, a second protection module, a first positive pole conduction module and a first negative pole conduction module. A positive electrode interface of the first Ethernet interface is connected with a first winding of the first transformer, a negative electrode interface of the first Ethernet interface is connected with a first winding of the second transformer, and the first positive electrode conduction module is electrically connected with the first transformer, the second transformer and the first protection module. The surge signal transmission module is used for transmitting a positive surge signal of a first Ethernet interface to the first protection module; and the first cathode conduction module is electrically connected with the first transformer, the second transformer and the second protection module, and is used for transmitting a cathode surge signal of the first Ethernet interface to the second protection module, so that the power supply stability is improved, and power supply interruption caused by surge impact is avoided.

Description

Technical Field

[0001] This application relates to the field of surge protection technology, and in particular to a surge protection circuit, power supply equipment and Ethernet power supply system. Background Technology

[0002] With the widespread adoption of Power over Ethernet (PoE) technology, power sourcing equipment (PSE), as a core component of network power supply systems, plays a crucial role in areas such as IP telephony systems, wireless access points, and network monitoring equipment. PoE technology achieves synchronous data and power transmission through standard Ethernet cables, significantly simplifying equipment deployment processes and effectively reducing overall cabling costs. However, in existing technologies, large inrush currents can cause power outages in the equipment, affecting its normal operation. Summary of the Invention

[0003] In view of this, embodiments of this application provide a surge protection circuit, power supply equipment, and Ethernet power supply system, which can effectively solve the problem in the prior art that when the surge current is large, the power supply equipment may lose power, thereby affecting the normal operation of the equipment.

[0004] In a first aspect, embodiments of this application provide a surge protection circuit, including: a first Ethernet interface, a first transformer, a second transformer, a first protection module, a second protection module, a first positive conduction module, and a first negative conduction module; The positive terminal of the first Ethernet interface is connected to the first winding of the first transformer, and the negative terminal of the first Ethernet interface is connected to the first winding of the second transformer. The first positive conduction module is electrically connected to the first transformer, the second transformer and the first protection module respectively. The first positive conduction module is used to transmit the positive surge signal of the first Ethernet interface to the first protection module. The first negative conduction module is electrically connected to the first transformer, the second transformer, and the second protection module, respectively. The first negative conduction module is used to transmit the negative surge signal of the first Ethernet interface to the second protection module.

[0005] In some embodiments, it further includes: a second Ethernet interface, a third transformer, a fourth transformer, a second positive conduction module, and a second negative conduction module; The positive terminal of the second Ethernet interface is connected to the first winding of the third transformer, and the negative terminal of the second Ethernet interface is connected to the first winding of the fourth transformer. The second positive terminal conduction module is electrically connected to the third transformer, the fourth transformer and the first protection module respectively. The second positive terminal conduction module is used to transmit the positive surge signal of the second Ethernet interface to the first protection module. The second negative conduction module is electrically connected to the third transformer, the fourth transformer and the second protection module respectively. The second negative conduction module is used to transmit the negative surge signal of the second Ethernet interface to the second protection module.

[0006] In some embodiments, the circuit further includes a π-type filter module, one end of which is connected to the center tap of the first winding of the first transformer, and the other end of which is connected to the power output terminal, for filtering the signal from the center tap.

[0007] In some embodiments, the π-type filter module includes a first electrolytic capacitor, a common-mode inductor, and a second electrolytic capacitor connected in parallel. One end of the common-mode inductor is connected to the center tap of the first winding of the first transformer, and the other end of the common-mode inductor is connected to the negative terminal of the power supply output.

[0008] In some embodiments, a third protection module, a fourth protection module, and an Ethernet chip are also included; One end of the third protection module is connected to the second winding of the first transformer, and the other end of the third protection module is electrically connected to the Ethernet chip. One end of the fourth protection module is connected to the second winding of the second transformer, and the other end of the fourth protection module is electrically connected to the Ethernet chip. The third protection module and the fourth protection module are used to provide surge protection for the Ethernet chip.

[0009] In some embodiments, the first positive conduction module includes a first diode, the positive terminal of the first diode is connected to the center tap of the first winding of the second transformer, and the negative terminal of the first diode is connected to the center tap of the first winding of the first transformer and the first protection module. The first negative electrode conduction module includes a second diode, the positive terminal of the second diode is connected to the second protection module, and the negative terminal of the second diode is connected to the positive terminal of the first diode.

[0010] In some embodiments, the first protection module is a first varistor; the second protection module is a second varistor, and the current carrying capacity of the first varistor and the second varistor is not less than a first preset capacity.

[0011] In some embodiments, the circuit further includes a fifth protection module, wherein an idle interface of the first Ethernet interface is electrically connected to the fifth protection module.

[0012] Secondly, embodiments of this application provide a power supply device, which includes at least one surge protection circuit as described in the first aspect above.

[0013] Thirdly, the present invention provides a Power over Ethernet (PoE) system, the PoE system comprising: a powered device and at least one power supply device as described in the second aspect above, electrically connected to the powered device.

[0014] The embodiments of this application have the following beneficial effects: The surge protection circuit of this application includes: a first Ethernet interface, a first transformer, a second transformer, a first protection module, a second protection module, a first positive conduction module, and a first negative conduction module. The positive interface of the first Ethernet interface is connected to the first winding of the first transformer, and the negative interface of the first Ethernet interface is connected to the first winding of the second transformer. The first positive conduction module is electrically connected to the first transformer, the second transformer, and the first protection module, and is used to transmit the positive surge signal of the first Ethernet interface to the first protection module. The first negative conduction module is electrically connected to the first transformer, the second transformer, and the second protection module, and is used to transmit the negative surge signal of the first Ethernet interface to the second protection module. This solution, through the positive and negative conduction modules, directs the surge signal to the corresponding protection module, optimizes the surge energy dissipation path, prevents surge energy from passing through the main power supply path, ensures that the power supply equipment does not lose power under surge impact, and improves power supply stability. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A first structural schematic diagram of a surge protection circuit according to an embodiment of this application is shown; Figure 2 A first circuit diagram of the surge protection circuit according to an embodiment of this application is shown; Figure 3 A second circuit diagram of the surge protection circuit according to an embodiment of this application is shown; Figure 4A schematic diagram illustrating the principle of forward surge discharge according to an embodiment of this application is shown; Figure 5 A schematic diagram illustrating the principle of negative surge discharge according to an embodiment of this application is shown; Figure 6 A third circuit diagram of the surge protection circuit according to an embodiment of this application is shown.

[0017] Key component symbols: 10: First Ethernet interface; 20: First transformer; 30: Second transformer; 40: First protection module; 50: Second protection module; 60: First positive conduction module; 70: First negative conduction module; 80: Second Ethernet interface; 90: Third transformer; 100: Fourth transformer; 110: Second positive conduction module; 120: Second negative electrode conduction module; 130: π-type filter module. Detailed Implementation

[0018] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0019] The components of the embodiments of this application described and illustrated in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0020] In the following text, the terms "comprising," "having," and their cognates, which may be used in various embodiments of this application, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more combinations thereof. Furthermore, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0021] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of this application pertain. Terms (such as those defined in commonly used dictionaries) shall be interpreted as having the same meaning as in their contextual meaning in the relevant technical field and shall not be construed as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of this application.

[0022] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0023] A surge signal refers to an abnormally high voltage pulse that appears briefly in a power system. It can be caused by various factors such as lightning strikes, switching operations, inductive load disconnection, and electrostatic discharge. It can cause equipment damage, system failures, and other hazards. For Power over Ethernet (PoE) equipment, Ethernet interfaces require surge protection.

[0024] An Ethernet interface is used to connect to an external Ethernet cable and receive power and data signals from the power supply device. An Ethernet interface typically includes 8 ports, numbered 1 to 8, which are used to connect one-to-one with the 8 wires (wires 1 to 8) in an Ethernet cable.

[0025] Interface 1 and interface 2 form a pair, called interface pair 1-2; interface 3 and interface 6 form a pair, called interface pair 3-6; interface 4 and interface 5 form a pair, called interface pair 4-5; and interface 7 and interface 8 form a pair, called interface pair 7-8.

[0026] The Power over Ethernet (PoE) standard defines two common power supply schemes: Scheme A and Scheme B.

[0027] In scheme A, wire pairs 1-2 and 3-6 are used for power supply. Specifically, the power supply method can be: wire pair 1-2 provides a negative voltage, and wire pair 3-6 provides a positive voltage; or wire pair 1-2 provides a positive voltage, and wire pair 3-6 provides a negative voltage. In this scheme, wire pairs 4-5 and 7-8 are idle wire pairs; in this application, "idle" means not used for power supply. When using scheme A, the corresponding interface pairs 1-2 and 3-6 are power supply interfaces, and interface pairs 4-5 and 7-8 are idle interfaces.

[0028] In Scheme B, power supply is provided by wire pairs 4-5 and 7-8, while wire pairs 1-2 and 3-6 are idle. Accordingly: interface pairs 4-5 and 7-8 are power supply interfaces; interface pairs 1-2 and 3-6 are idle interfaces.

[0029] In embodiments of the present invention, the technical principle of surge protection is illustrated by taking the example of providing negative voltage to line pair 1-2 and positive voltage to line pair 3-6. It should be noted that the above examples are only used to explain the technical solution of this application and do not constitute a limitation on the scope of protection of this application.

[0030] A transformer, power controller, and power output terminal are installed at the interface. The transformer provides electrical isolation, signal coupling, and separation of DC power supply and data signals. The power controller manages the power supply process, including power detection, grading, current limiting, and power failure protection. The power output terminal outputs the processed DC power signal to the load circuit of the downstream powered device. The power supply interfaces of the Ethernet interface are connected to the primary winding of the transformer, and the secondary winding of the transformer outputs the coupled DC power signal and data signal. Specifically, the power controller controls the transmission of the DC power signal to the power output terminal, forming the main power supply path.

[0031] Surge protection software such as varistors and gas discharge tubes are typically installed at the power output. However, when the surge current is large, it may cause power outages in the power supply equipment, thus affecting its normal operation. This solution uses positive and negative conduction modules to direct the surge signal to the corresponding protection modules, optimizing the surge energy discharge path. This ensures that the surge energy does not pass through the main power supply path, guaranteeing that the power supply equipment does not lose power under surge impact and improving power supply stability.

[0032] The surge protection circuit will be explained below with reference to some specific embodiments.

[0033] Figure 1 A schematic diagram of a surge protection circuit according to an embodiment of this application is shown. Exemplarily, the surge protection circuit includes: a first Ethernet interface 10, a first transformer 20, a second transformer 30, a first protection module 40, a second protection module 50, a first positive conduction module 60, and a first negative conduction module 70.

[0034] The first protection module 40 and the second protection module 50 can be configured according to the actual application. The structures of the first protection module 40 and the second protection module 50 can be the same or different. Each protection module can be a varistor or a gas discharge tube, etc. For example, the first protection module 40 is the first varistor RV1; the second protection module 50 is the second varistor RV2.

[0035] The parameters of the first varistor RV1 and the second varistor RV2 can be set according to the actual application. For example, the current-carrying capacity of the first varistor RV1 and the second varistor RV2 should not be less than 2.5kA. In surge testing standards, a 1.2 / 50 impulse voltage waveform is commonly used. During testing, the power supply internal resistance is 42Ω. If a 10kV voltage is applied, the theoretical surge current is approximately 10kV / 42Ω ≈ 238A. However, in practical applications, the transient surge current may reach 5 to 10 times this rated value, i.e., between 1.2kA and 2.4kA. Therefore, to ensure reliable operation of the varistor under extreme surge conditions, its current-carrying capacity needs to be designed to be ≥2.5kA. By setting a current-carrying capacity ≥2.5kA, the varistor's withstand capability in extreme surge events can be significantly improved, thereby enhancing the anti-disturbance performance and long-term stability of the entire circuit system. This enables the equipment to protect against 10kV surge signals, extends the equipment's service life, and improves the equipment's operational reliability in complex electromagnetic environments.

[0036] Exemplary, the first transformer 20 is transformer T1, and the second transformer 30 is transformer T2. The positive terminal of the first Ethernet interface 10 of the first transformer 20 is connected to the first winding of the first transformer 20, and the negative terminal of the first Ethernet interface 10 is connected to the first winding of the second transformer 30; specifically, the positive terminal is interface pair 3-6, and the negative terminal is interface pair 1-2.

[0037] The first positive conduction module 60 is electrically connected to the first transformer 20, the second transformer 30, and the first protection module 40, respectively. The first positive conduction module 60 is used to transmit the positive surge signal of the first Ethernet interface 10 to the first protection module 40. The first negative conduction module 70 is electrically connected to the first transformer 20, the second transformer 30, and the second protection module 50, respectively. The first negative conduction module 70 is used to transmit the negative surge signal of the first Ethernet interface 10 to the second protection module 50. It is understood that the first positive conduction module 60 is electrically connected to the center tap of the first winding of the first transformer 20 and the center tap of the first winding of the second transformer 30, and the first negative conduction module 70 is electrically connected to the center tap of the first winding of the first transformer 20 and the center tap of the first winding of the second transformer 30. Specifically, the first winding of each transformer is the primary winding.

[0038] Specifically, the first positive conduction module 60 can be located between the center tap of the first transformer 20 and the first protection module 40 to transmit the positive surge signal of the positive interface to the first protection module 40; the first positive conduction module 60 can also be located between the center tap of the second transformer 30 and the first protection module 40 to transmit the positive surge signal of the negative interface to the first protection module 40; the first positive conduction module 60 can also be located between the center tap of the first transformer 20 and the center tap of the second transformer 30 and the first protection module 40 to transmit the positive surge signals of the positive and negative interfaces to the first protection module 40. Similarly, the first negative conduction module 70 can be located between the center tap of the first winding of the first transformer 20 and the center tap of the first winding of the second transformer 30.

[0039] By setting up a first positive conduction module 60 and a first negative conduction module 70, which are electrically connected to the center taps of the primary windings of the first transformer 20 and the second transformer 30, and their corresponding protection modules, effective identification and directional transmission of positive and negative surge signals in the Ethernet interface are achieved. This structure can guide the surge signal to the corresponding protection module based on its polarity, thereby achieving independent suppression and protection against positive and negative polarity surges, avoiding mutual interference between surges of different polarities, and improving the targeting and response efficiency of surge protection. Furthermore, the surge energy dissipation path is optimized so that surge energy does not pass through the main power supply path, ensuring that the power supply equipment does not lose power under surge impact, thus improving power supply stability. In addition, by sharing the connection between the center taps of the two transformers and the same protection module, the system's compatibility and scalability in multi-line power supply scenarios (such as Scheme A and Scheme B) are enhanced, improving the overall circuit's stability and safety in complex electromagnetic environments.

[0040] Exemplary, Figure 2 It shows the corresponding Figure 1 The circuit diagram of the surge protection circuit shows that the first positive conduction module 60 includes a first diode D1. The positive terminal of the first diode D1 is connected to the center tap of the first winding of the second transformer 30, and the negative terminal of the first diode D1 is connected to the center tap of the first winding of the first transformer 20 and the first protection module 40. The first diode D1 is used to transmit the positive surge signal of the negative interface to the first protection module 40. The first negative conduction module 70 includes a second diode D2. The positive terminal of the second diode D2 is connected to the second protection module 50, and the negative terminal of the second diode D2 is connected to the positive terminal of the first diode D1. The second diode D2 is used to transmit the negative surge signal of the negative interface to the second protection module 50, and also to transmit the negative surge signal of the positive interface to the second protection module 50 through the first diode D1. Alternatively, the negative surge signal of the positive interface can also flow directly to the first protection module 40. Exemplarily, the current carrying capacity of each diode is not less than 1A.

[0041] By setting the conduction module as a diode structure and utilizing its unidirectional conductivity, directional transmission and selective suppression of surge signals of different polarities can be achieved. This ensures that the surge signal is transmitted to the corresponding protection module only along a preset path, while also preventing current backflow or interference between protection modules. This avoids malfunctions or device damage caused by surge energy oscillating back and forth between multiple protection devices. Furthermore, by directly guiding the surge signal to the corresponding protection module, the surge discharge path is shortened, signal delay and energy loss are reduced, thereby improving the system's response speed and suppression efficiency for transient surges.

[0042] In one embodiment, based on the above embodiments, the power supply equipment may be equipped with multiple Ethernet interfaces, each of which can be configured according to... Figure 2 The surge protection circuit shown can be configured according to its principle. Multiple Ethernet interfaces can also share a single protection module. For example, multiple Ethernet interfaces can share a single protection module. Figure 3 As shown, the surge protection circuit also includes: a second Ethernet interface 80, a third transformer 90, a fourth transformer 100, a second positive conduction module 110, and a second negative conduction module 120. The positive interface of the second Ethernet interface 80 is connected to the first winding of the third transformer 90, and the negative interface of the second Ethernet interface 80 is connected to the first winding of the fourth transformer 100. Similarly, the positive interfaces are interface pairs 3-6, and the negative interfaces are interface pairs 1-2.

[0043] The second positive conduction module 110 is electrically connected to the third transformer 90, the fourth transformer 100, and the first protection module 40, respectively. The second positive conduction module 110 is used to transmit the positive surge signal of the second Ethernet interface 80 to the first protection module 40. The second negative conduction module 120 is electrically connected to the third transformer 90, the fourth transformer 100, and the second protection module 50, respectively. The second negative conduction module 120 is used to transmit the negative surge signal of the second Ethernet interface 80 to the second protection module 50. Specifically, the second positive conduction module 110 is a third diode D3. The positive terminal of the third diode D3 is connected to the center tap of the first winding of the fourth transformer 100, and the negative terminal of the third diode D3 is connected to the center tap of the first winding of the third transformer 90 and one end of the first varistor RV1. The second negative conduction module 120 is a fourth diode D4. The positive terminal of the fourth diode D4 is connected to one end of the second varistor RV2, and the negative terminal of the fourth diode D4 is connected to the positive terminal of the third diode D3.

[0044] The shared protection module structure design for multiple Ethernet interfaces guides surge signals from different interfaces to the same protection module for centralized processing, reducing the number of protection devices and circuit space occupation, effectively simplifying circuit layout, reducing hardware costs, and improving system integration. At the same time, while ensuring surge protection performance, it achieves efficient resource utilization, facilitates unified surge energy discharge and control, and improves the maintainability and consistency of the protection circuit.

[0045] In one embodiment, Figure 4 This is a schematic diagram illustrating the principle of forward surge discharge. When a forward surge occurs, the surge signal enters the power supply equipment from the power supply interface of the Ethernet interface. The surge energy is then guided to the protection module via the first positive conduction module 60 and the second positive conduction module 110, thereby effectively dissipating the forward surge. Specifically, for a forward surge on power line pair 3-6, the surge is directly transmitted to the input terminal of the first varistor RV1, where it is discharged. For a forward surge on power line pair 1-2, the surge signal is guided to the first varistor RV1 via the first diode D1 and the third diode D3, where it is discharged, preventing it from flowing into the main power supply path.

[0046] In one embodiment, Figure 5 This is a schematic diagram illustrating the principle of negative surge discharge. When a negative surge occurs, the surge signal enters the power supply equipment from the power supply interface of the Ethernet interface, and the surge energy is guided to the protection module through the first negative conduction module 70 and the second negative conduction module 120, thereby effectively discharging the positive surge. Specifically, for negative surges on power supply line pair 3-6, the surge is directly transmitted to the input terminal of the first varistor RV1, where it is discharged. For negative surges on power supply line pair 1-2, the surge signal is guided to the second varistor RV2 through the second diode D2 and the fourth diode D4, where it is discharged, preventing it from flowing into the main power supply path.

[0047] In one embodiment, based on the above embodiments, Figure 6 Another circuit diagram of the surge protection circuit according to an embodiment of this application is shown. The circuit further includes a π-type filter module 130. One end of the π-type filter module 130 is connected to the center tap of the first winding of the first transformer 20, and the other end of the π-type filter module 130 is connected to the power output terminal for filtering the signal from the center tap. Specifically, the π-type filter module 130 is located at the power output terminal of the main power supply path. Exemplarily, the power output terminal is represented by V+ and V-. The DC power signal supplies power to the powered equipment through the π-type filter module 130.

[0048] The π-type filter module 130 can be configured according to the actual application. For example, Figure 6 As shown, the π-type filter module 130 includes a first electrolytic capacitor C1, a common-mode inductor L1, and a second electrolytic capacitor C2 connected in parallel. One end of the common-mode inductor L1 is connected to the center tap of the first winding of the first transformer 20, and the other end of the common-mode inductor L1 is connected to the negative terminal V- of the power output. The first electrolytic capacitor C1 and the second electrolytic capacitor C2 are respectively disposed at the front and rear ends of the common-mode inductor L1, forming a two-stage filtering and energy absorption structure. This design is used to absorb the transient energy remaining in the circuit after a surge impact, preventing the residual energy from causing voltage fluctuations or false triggering of the power supply equipment, thereby ensuring the continuous and stable operation of the power supply system during surge events and avoiding abnormal power outages or power interruptions caused by surge interference. Exemplarily, the inductance of the common-mode inductor L1 is not less than 500uH, and the capacitance of each electrolytic capacitor is not less than 100uF.

[0049] Because the differential signal path formed by the Ethernet chip and the transformer may be unbalanced, some common-mode surge energy may be converted into differential-mode signals, affecting the normal operation of the Ethernet chip. To solve this problem, a resistor is connected in series on the differential signal line between the transformer secondary winding and the Ethernet chip to absorb and dissipate residual surge energy coupled from the primary side, thereby preventing surge energy from interfering with or damaging the Ethernet chip. Figure 6 As shown, the surge protection circuit also includes a third protection module, a fourth protection module, and an Ethernet chip; one end of the third protection module is connected to the second winding of the first transformer 20, and the other end of the third protection module is electrically connected to the Ethernet chip; one end of the fourth protection module is connected to the second winding of the second transformer 30, and the other end of the fourth protection module is electrically connected to the Ethernet chip. The third and fourth protection modules are used to provide surge protection for the Ethernet chip.

[0050] Specifically, the third protection module consists of a first resistor R1 and a second resistor R2 connected in series between the second winding of the first transformer 20 and the Ethernet chip. The fourth protection module consists of a third resistor R3 and a fourth resistor R4 connected in series between the second winding of the second transformer 30 and the Ethernet chip. These resistors dampen and absorb the differential-mode signal converted from surge energy, preventing it from entering the Ethernet chip and improving the system's immunity. This structure not only provides reliable protection for the Ethernet chip but also reduces circuit costs, improving the system's economy and practicality.

[0051] Furthermore, the surge protection circuit also includes a fifth protection module, which is electrically connected to the idle interfaces of the first Ethernet interface 10. Specifically, the idle interfaces are interface pairs 4-5 and 7-8. Exemplarily, the fifth protection module is a third varistor, which is used to discharge surge signals from interface pairs 4-5 and 7-8. Through the fifth protection module, surge protection coverage of the idle interfaces is achieved, improving the overall interface safety.

[0052] This application also provides a power supply device, exemplary of which includes the surge protection circuit described above.

[0053] This application also provides a Power over Ethernet (PoE) system, which includes a powered device and the aforementioned power supply device electrically connected to the powered device.

[0054] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that, in alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0055] In addition, the functional modules or units in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0056] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a smartphone, personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0057] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A surge protection circuit, characterized in that, include: The system includes a first Ethernet interface, a first transformer, a second transformer, a first protection module, a second protection module, a first positive conduction module, and a first negative conduction module. The positive terminal of the first Ethernet interface is connected to the first winding of the first transformer, and the negative terminal of the first Ethernet interface is connected to the first winding of the second transformer. The first positive conduction module is electrically connected to the first transformer, the second transformer and the first protection module respectively. The first positive conduction module is used to transmit the positive surge signal of the first Ethernet interface to the first protection module. The first negative conduction module is electrically connected to the first transformer, the second transformer, and the second protection module, respectively. The first negative conduction module is used to transmit the negative surge signal of the first Ethernet interface to the second protection module.

2. The surge protection circuit according to claim 1, characterized in that, Also includes: Second Ethernet interface, third transformer, fourth transformer, second positive conduction module and second negative conduction module; The positive terminal of the second Ethernet interface is connected to the first winding of the third transformer, and the negative terminal of the second Ethernet interface is connected to the first winding of the fourth transformer. The second positive terminal conduction module is electrically connected to the third transformer, the fourth transformer and the first protection module respectively. The second positive terminal conduction module is used to transmit the positive surge signal of the second Ethernet interface to the first protection module. The second negative conduction module is electrically connected to the third transformer, the fourth transformer and the second protection module respectively. The second negative conduction module is used to transmit the negative surge signal of the second Ethernet interface to the second protection module.

3. The surge protection circuit according to claim 1, characterized in that, The circuit also includes a π-type filter module, one end of which is connected to the center tap of the first winding of the first transformer, and the other end of which is connected to the power output terminal, for filtering the signal from the center tap.

4. The surge protection circuit according to claim 3, characterized in that, The π-type filter module includes a first electrolytic capacitor, a common-mode inductor, and a second electrolytic capacitor connected in parallel. One end of the common-mode inductor is connected to the center tap of the first winding of the first transformer, and the other end of the common-mode inductor is connected to the negative terminal of the power supply output.

5. The surge protection circuit according to claim 1, characterized in that, It also includes a third protection module, a fourth protection module, and an Ethernet chip; One end of the third protection module is connected to the second winding of the first transformer, and the other end of the third protection module is electrically connected to the Ethernet chip. One end of the fourth protection module is connected to the second winding of the second transformer, and the other end of the fourth protection module is electrically connected to the Ethernet chip. The third protection module and the fourth protection module are used to provide surge protection for the Ethernet chip.

6. The surge protection circuit according to claim 1, characterized in that, The first positive conduction module includes a first diode, the positive terminal of the first diode is connected to the center tap of the first winding of the second transformer, and the negative terminal of the first diode is connected to the center tap of the first winding of the first transformer and the first protection module. The first negative electrode conduction module includes a second diode, the positive terminal of the second diode is connected to the second protection module, and the negative terminal of the second diode is connected to the positive terminal of the first diode.

7. The surge protection circuit according to claim 1, characterized in that, The first protection module is a first varistor; the second protection module is a second varistor, and the current carrying capacity of the first varistor and the second varistor is not less than a first preset capacity.

8. The surge protection circuit according to claim 1, characterized in that, The circuit also includes a fifth protection module, and the idle interface of the first Ethernet interface is electrically connected to the fifth protection module.

9. A power supply device, characterized in that, The power supply equipment includes a surge protection circuit as described in any one of claims 1-8.

10. A Power over Ethernet (PoE) system, characterized in that, The Power over Ethernet system includes: a powered device and a power supply device as described in claim 9, which is electrically connected to the powered device.

Images