Signal protection circuit, method and apparatus for power supply system

Abstract

The application discloses a signal protection circuit, method and device of a power supply system. The circuit comprises a discharge tube which is triggered to be turned on by lightning energy so that the lightning energy is released at an antenna port; and a shutdown device which is connected between a signal ground of the power supply system and a negative busbar of the power supply system and is used for blocking a short-circuit current formed between the negative busbar and a positive busbar of the power supply system or shutting down the discharge tube based on the short-circuit current. The application solves the technical problem that devices in the power supply system are easily damaged when the protection circuit is triggered to work and after the protection circuit works.

Description

Technical Field

[0001] This invention relates to the field of signal circuits, and more specifically, to a signal protection circuit, method, and apparatus for a power supply system. Background Technology

[0002] Currently, the commonly used port surge protection in power systems mainly consists of devices such as gas discharge tubes and varistors. Due to the unique advantages of gas discharge tubes, such as large inter-electrode insulation resistance and small parasitic capacitance, they are particularly suitable for the protection of high-frequency signals, especially radio frequency signal antenna ports.

[0003] However, in communication power supply systems, to reduce the monitoring design cost of the power supply system, save printed circuit board (PCB) space, and improve the accuracy of bus voltage sampling, the grounding terminal GND and the negative busbar of the power supply system are connected in a non-isolated manner. The positive busbar grounding wire (Protecting Earthing, PE) (0V) of the power supply system, if the RF signal antenna port is directly protected by a gas discharge tube, the gas discharge tube between the common-mode protection PE and the power supply system GND is essentially directly connected between the positive and negative busbars (maximum 60VDC). This can lead to a short circuit if the gas discharge tube is triggered by lightning energy and discharges, due to the existing busbar voltage, it cannot be turned off in time, resulting in damage to the power supply system components. Furthermore, in some cases, such as the protection of the DC busbar output port, the problem of the discharge tube's freewheeling shutdown can be solved by adding a varistor in series with the discharge tube. However, this design increases the lightning residual voltage at the protected port, which can easily damage the port components, especially for lightning-sensitive antenna ports.

[0004] There is currently no effective solution to the problem of easy damage to components in the aforementioned power supply system. Summary of the Invention

[0005] This invention provides a signal protection circuit, method, and apparatus for a power supply system, at least addressing the technical problem that devices in a power supply system are easily damaged when and after the protection circuit is triggered.

[0006] According to one aspect of the present invention, a signal protection circuit for a power supply system is provided, comprising: a discharge tube for being turned on by lightning energy, so that the lightning energy is released at the antenna port; and a shutdown device connected between the signal ground of the power supply system and the negative busbar of the power supply system, for blocking the short-circuit current formed between the negative busbar and the positive busbar of the power supply system, or for shutting off the discharge tube based on the short-circuit current.

[0007] Optionally, the protection circuit includes an antenna port connected to the discharge tube and the transmitting antenna.

[0008] Optionally, the shutdown device includes a thermistor connected in series with the power supply system's filter circuit between the signal ground and the negative busbar.

[0009] Optionally, the thermistor is disposed in the target circuit, which includes a positive busbar and a negative busbar, and includes a circuit other than the circuit consisting of the signal ground, the discharge tube and the system ground terminal.

[0010] Optionally, the thermistor is placed in the power supply circuit of the power supply system, the power supply circuit is placed in the target circuit, and the power supply circuit is the single-board power supply circuit.

[0011] Optionally, the shut-off device includes: a circuit breaker connected to the discharge tube, used to block the formation of a short-circuit current between the negative busbar and the positive busbar by being triggered by a short-circuit current, and to prevent the discharge tube from entering the freewheeling state after the lightning energy is released.

[0012] According to another aspect of the present invention, a signal protection method for a power supply system is also provided, comprising: detecting lightning energy, wherein the lightning energy is released at an antenna port; during the release of lightning energy, when a trigger discharge tube is in a conducting state, controlling a shutdown device to block the formation of a short-circuit current between the negative busbar and the positive busbar of the power supply system, wherein the short-circuit current is formed by the discharge tube being in a conducting state or a freewheeling state; and after the release of lightning energy, when the discharge tube is in a freewheeling state, controlling the shutdown device to shut off the discharge tube based on the short-circuit current.

[0013] Optionally, during the process when the lightning energy triggers the discharge tube to be in the conducting state, the residual voltage of the lightning energy at the antenna port is lower than the target threshold.

[0014] Optionally, the shut-off device is a thermistor, and the shut-off device based on the short-circuit current controls the discharge tube to turn off, including: triggering the thermistor to change from a low impedance state to a high impedance state by the short-circuit current; and turning off the discharge tube by the thermistor in the high impedance state.

[0015] Optionally, the holding current of the thermistor is greater than the current flowing through the thermistor when the power supply system is in normal operating condition; the switching current of the thermistor is less than the minimum current among the multiple maximum operating currents corresponding to multiple components in the power supply system.

[0016] Optionally, triggering the thermistor to change from a low impedance state to a high impedance state by means of a short-circuit current includes: triggering the thermistor to change from a low impedance state to a high impedance state by means of a short-circuit current before each component reaches its corresponding maximum operating current.

[0017] Optionally, the method further includes: determining that the thermistor is in a low-impedance state when the current flowing through the thermistor is less than the holding current; and determining that the thermistor is in a high-impedance state when the current flowing through the thermistor is greater than the switching current.

[0018] Optionally, no current flows between the signal ground and the negative busbar when the thermistor is in a low-impedance state, or the current flowing through it is lower than the switching current of the thermistor.

[0019] Optionally, the shut-off device is a circuit breaker, and the shut-off device is shut down based on the short-circuit current, including: triggering the circuit breaker to work by the short-circuit current to block the formation of a short-circuit loop between the negative busbar and the positive busbar of the power system during the release of lightning energy, or shutting down the discharge tube after the release of lightning energy.

[0020] According to another aspect of the present invention, a signal protection device for a power supply system is also provided, comprising: a detection unit for detecting lightning energy, wherein the lightning energy is released at an antenna port; a first control unit for controlling a shutdown device to block the formation of a short-circuit current between the negative busbar and the positive busbar of the power supply system when the trigger discharge tube is in a conducting state during the release of lightning energy, wherein the short-circuit current is formed by the discharge tube being in a conducting state or a freewheeling state; and a second control unit for controlling the shutdown device to shut off the discharge tube based on the short-circuit current when the discharge tube is in a freewheeling state after the release of lightning energy.

[0021] In this embodiment of the invention, a discharge tube is used to be triggered by lightning energy to conduct, allowing the lightning energy to be released at the antenna port. A shutdown device is connected between the signal ground of the power system and the negative busbar of the power system to block the short-circuit current formed between the negative and positive busbars of the power system, or to shut down the discharge tube based on the short-circuit current. In other words, this application triggers the discharge tube to conduct using lightning energy. When the discharge tube is in a conducting state during the release of lightning energy, the shutdown device connected between the signal ground and the negative busbar of the power system blocks the short-circuit current formed between the negative and positive busbars of the power system. Alternatively, when the discharge tube is in a freewheeling state after the release of lightning energy, the shutdown device shuts down the discharge tube based on the short-circuit current. This achieves timely shutdown of the discharge tube to protect the devices in the power system from damage, thereby achieving the purpose of protecting the signal of the power system. This solves the technical problem that devices in the power system are easily damaged when and after the protection circuit is triggered, thus achieving the technical effect of protecting the devices in the power system. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0023] Figure 1 This is a schematic diagram of a signal protection circuit for a power supply system according to an embodiment of the present invention;

[0024] Figure 2 This is a flowchart of a signal protection method for a power supply system according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of a signal protection circuit for a power supply system based on related technologies;

[0026] Figure 4 This is a schematic diagram of a signal protection circuit for another power supply system according to an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of a signal protection circuit for a power supply system according to an embodiment of the present invention;

[0028] Figure 6 This is a schematic diagram of a signal protection device for a power supply system according to an embodiment of the present invention. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] Example 1

[0032] According to an embodiment of the present invention, a signal protection circuit for a power supply system is provided.

[0033] Figure 1 This is a schematic diagram of a signal protection circuit for a power supply system according to an embodiment of the present invention. Figure 1 As shown, the signal protection circuit 10 of the power supply system may include a discharge tube 11 and a shutdown device 12.

[0034] The discharge tube 11 is used to be turned on by lightning energy, so that the lightning energy is released at the antenna port.

[0035] In this embodiment, the signal protection circuit 10 of the power system may include a discharge tube 11, which can be triggered by lightning energy to conduct, thereby releasing the lightning energy at the antenna port.

[0036] Optionally, in this embodiment, when the power system is working normally, no current flows between the GND and the negative busbar of the power system. When the power system is struck by lightning energy, the discharge tube 11 will conduct to discharge. At this time, a large short-circuit current is formed between the positive busbar and the negative busbar, thus isolating the positive busbar and the negative busbar and preventing the formation of a short-circuit loop, thereby protecting the power system.

[0037] The shut-off device 12 is connected between the signal ground of the power system and the negative busbar of the power system, and is used to block the short-circuit current formed between the negative busbar and the positive busbar of the power system, or to shut off the discharge tube 11 based on the short-circuit current.

[0038] In this embodiment, the signal protection circuit 10 of the power system may further include a shutdown device 12, which may be connected between the signal ground and the negative busbar of the power system. During the release of lightning energy, the discharge tube 11 is triggered to form a conducting state. At this time, the shutdown device 12 can block the short-circuit current formed between the negative busbar and the positive busbar of the power system. After the release of lightning energy, the discharge tube 11 is in a freewheeling state. At this time, the shutdown device 12 can shut down the discharge tube 11 based on the short-circuit current formed between the negative busbar and the positive busbar of the power system.

[0039] In the above embodiments, the short-circuit current can be formed between the negative busbar and the positive busbar of the power supply system when the discharge tube 11 is in the conducting state or the freewheeling state.

[0040] Optionally, in this embodiment, after the lightning strike energy dissipates, the discharge tube 11 can be turned off by preventing it from continuing to discharge. After the discharge tube 11 is turned off, the power system can be restored to its initial normal operating state.

[0041] As an optional implementation, the protection circuit includes an antenna port connected to a discharge tube and a transmitting antenna.

[0042] In this embodiment, the signal protection circuit 10 of the power supply system may further include an antenna port, which can be connected to the discharge tube 11. When the lightning energy triggers the discharge tube 11 to conduct, the lightning energy is released at the antenna port, and a residual voltage of the lightning energy is generated at the antenna port. This residual voltage can be lower than the target threshold, that is, the residual voltage at the antenna port is the lowest. This will prevent the problem of damage to downstream devices during a lightning strike caused by raising the residual voltage of the lightning protection circuit. Optionally, the residual voltage in this embodiment is the residual voltage caused by the absence of other superimposed protection devices.

[0043] Optionally, the target threshold in this embodiment can be preset. The target threshold can be the voltage value at which the signal protection circuit 10 of the power supply system will not be damaged by lightning strikes and the residual voltage is minimized.

[0044] Optionally, the transmitting antenna in this embodiment can be used to receive and / or transmit wireless signals.

[0045] As an optional implementation, the shut-off device 12 includes a thermistor for being triggered by a short-circuit current to switch from a low-impedance state to a high-impedance state, thereby blocking the short-circuit current or shutting off the discharge tube 11 which is in the conducting state.

[0046] In this embodiment, the shutdown device 12 may include a thermistor. When a short-circuit current is generated between the negative busbar and the positive busbar of the power system, the short-circuit current can trigger the thermistor to change from a low impedance state to a high impedance state, thereby blocking the short-circuit current or turning off the discharge tube 11 in the conducting state, thus protecting the power system.

[0047] Optionally, in this embodiment, when the power system is operating normally, since no current flows between the GND and the negative busbar of the power system, the resistance of the aforementioned thermistor is very small, close to a short circuit, and thus will not affect other functional performance of the power system. When the power system is subjected to external lightning strike energy, the discharge tube 11 discharges, resulting in a large short-circuit current between the positive and negative busbars. This short-circuit current flows through the aforementioned thermistor, causing the thermistor to heat up and generate instantaneous impedance. This causes the thermistor to change from a low impedance state to a high impedance state in a short time. The thermistor in the high impedance state will prevent the discharge tube 11 from continuing to discharge, thus the discharge tube 11 can be turned off by the high-configuration thermistor.

[0048] Optionally, the thermistor in this embodiment can be a positive temperature coefficient (PTC) thermistor.

[0049] Optionally, the type of PTC thermistor in this embodiment can be determined based on the actual application.

[0050] As an alternative implementation, a thermistor in a high-impedance state is used to separate the negative busbar and the positive busbar.

[0051] In this embodiment, when the thermistor enters a high-impedance state, the positive busbar and the negative busbar can be separated by the thermistor in this high-impedance state, thus preventing the formation of a short-circuit loop and protecting the power supply system.

[0052] As an alternative implementation, the thermistor is connected in series with the power supply system's filter circuit between the signal ground and the negative busbar.

[0053] In this embodiment, the power supply system may also include a filter circuit, which can be used to improve the electromagnetic compatibility (EMC) performance of the power supply system. A thermistor can be connected in series with the filter circuit between the signal ground and the negative busbar of the power supply system.

[0054] Optionally, the filtering circuit in this embodiment may include an RF matching filter circuit.

[0055] Optionally, the connection between the thermistor and GND and the negative busbar in this embodiment is only for providing a unified reference for sampling analog quantities such as busbar voltage. No current flows during normal operation, therefore the holding current of the PTC thermistor can be selected as a very small value. However, under normal circumstances, the holding current of the PTC thermistor needs to be greater than the current flowing during normal operation, while the switching current needs to be less than the minimum maximum current that all devices in the loop circuit can withstand. This ensures that the PTC thermistor can operate in a low-impedance state during normal operation. After the discharge tube is triggered by a lightning strike, the PTC thermistor enters a high-impedance state before the device reaches its maximum operating current, thereby protecting the components of the power supply system from damage.

[0056] It should be noted that the position of the thermistor in this embodiment can be anywhere on the path from GND to the negative busbar.

[0057] As an optional implementation, the thermistor is disposed in the target circuit, which includes a positive busbar and a negative busbar, and includes a circuit other than the circuit consisting of the signal ground, the discharge tube 11 and the system ground terminal.

[0058] In this embodiment, the thermistor can be placed in a loop consisting of a positive busbar and a negative busbar, and the thermistor is not placed in a loop consisting of a signal ground, a discharge tube 11 and a system ground terminal.

[0059] As an optional implementation, the thermistor is placed in the power supply circuit of the power supply system, the power supply circuit is placed in the target circuit, and the power supply circuit is a single-board power supply circuit.

[0060] In this embodiment, the power supply system may further include a power supply circuit, which can be used to assist the power supply system in providing power. The thermistor may be located in the power supply circuit, which may be located in a circuit consisting of a positive busbar and a negative busbar, and not in a circuit consisting of signal ground, discharge tube 11 and system ground terminal.

[0061] In this embodiment, the single-board power supply circuit can also be called the single-board auxiliary power supply circuit.

[0062] As an optional implementation, the off discharge tube 11 is used to trigger the thermistor to change from a high impedance state to a low impedance state, and the thermistor in the low impedance state is used to enable the power supply system to be in normal working condition.

[0063] In this embodiment, after the discharge tube 11 is turned off, since no current flows through the thermistor, the thermistor will quickly change from a high impedance state to a low impedance state. At this time, the thermistor in the low impedance state can restore the power system to its initial normal working state. In this way, after the discharge tube 11 is triggered by lightning to discharge, the PTC thermistor can enter a high impedance state before the device reaches its maximum operating current, thereby achieving the purpose of protecting the components of the power system from damage.

[0064] As an optional implementation, the shut-off device 12 includes: a circuit breaker connected to the discharge tube 11, used to block the formation of a short-circuit current between the negative busbar and the positive busbar by being triggered by a short-circuit current, and to prevent the discharge tube 11 from entering the freewheeling state after the lightning energy is released.

[0065] In this embodiment, the shut-off device 12 may also include a circuit breaker, which can be connected to the discharge tube 11. When a short-circuit current is generated between the negative busbar and the positive busbar of the power system, the circuit breaker can be triggered to block the short-circuit current and prevent the discharge tube 11 from entering the freewheeling state after the lightning energy is released, thereby achieving the purpose of protecting the power system.

[0066] Optionally, the circuit breaker in this embodiment can be a smart circuit breaker.

[0067] The signal protection circuit of the power system in this embodiment is triggered by lightning energy to turn on the discharge tube. When the discharge tube is in the conducting state during the release of lightning energy, the short-circuit current formed between the negative bus and the positive bus of the power system is blocked by a shutdown device connected between the signal ground and the negative bus of the power system. Alternatively, when the discharge tube is in the freewheeling state after the release of lightning energy, the shutdown device turns off the discharge tube based on the short-circuit current. This achieves timely shutdown of the discharge tube to protect the devices in the power system from damage, thereby achieving the purpose of protecting the signal of the power system. This solves the technical problem that the devices in the power system are easily damaged when and after the protection circuit is triggered, and achieves the technical effect of protecting the devices in the power system.

[0068] Example 2

[0069] According to an embodiment of the present invention, an embodiment of a signal protection method for a power supply system is also provided. It should be noted that the signal protection method for the power supply system can be executed by the signal protection circuit of the power supply system in Embodiment 1. The steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than that shown here.

[0070] Figure 2 This is a flowchart of a signal protection method for a power supply system according to an embodiment of the present invention. Figure 2 As shown, the method may include the following steps:

[0071] Step S202: Detect lightning strike energy, wherein the lightning strike energy is released at the antenna port.

[0072] In the technical solution provided by step S202 of the present invention, lightning energy can be detected in real time at the antenna port. After lightning energy is detected at the antenna port, the lightning energy can be released at the antenna port to avoid damage to the power system.

[0073] Step S204: During the release of lightning energy, when the trigger discharge tube is in the on state, the control shutdown device blocks the formation of a short-circuit current between the negative busbar and the positive busbar of the power supply system. The short-circuit current is formed by the discharge tube being in the on state or in the freewheeling state.

[0074] In the technical solution provided by step S204 of the present invention, after lightning energy is detected, if the lightning energy is being released, the discharge tube is activated and in a conducting state. When the discharge tube is activated, the shut-off device can be controlled to block the formation of a short circuit between the negative busbar and the positive busbar of the power system, thereby generating a short circuit current between the negative busbar and the positive busbar of the power system. This prevents the lightning energy from passing between the negative busbar and the positive busbar of the power system, thus achieving the purpose of protecting the equipment or devices.

[0075] In the above embodiment, when the power system is working normally, no current flows between the GND and the negative busbar of the power system. When the power system is struck by lightning energy, the discharge tube will conduct and discharge. At this time, the voltage between the positive busbar and the negative busbar will form a large short-circuit current in the circuit in a short time through the freewheeling discharge tube. This short-circuit current can isolate the positive busbar and the negative busbar, preventing the formation of a short-circuit loop, thereby protecting the power system.

[0076] Step S206: After the lightning strike energy is released, when the discharge tube is in a freewheeling state, the discharge tube is turned off by the short-circuit current-controlled shut-off device.

[0077] In the technical solution provided by step S206 of the present invention, after lightning energy is detected, if the lightning energy has been released, the discharge tube is triggered to be in the freewheeling state. When the discharge tube is in the freewheeling state, since the discharge tube can generate a short-circuit current between the negative busbar and the positive busbar of the power system in the freewheeling state, the discharge tube can be turned off by controlling the shutdown device through the short-circuit current, so as to avoid the discharge tube being in the freewheeling state for a long time and damaging the equipment or device.

[0078] Optionally, in this embodiment, after the lightning strike energy disappears, the discharge tube can be shut off because it can no longer discharge. After the discharge tube is shut off, the power system can be restored to its initial normal operating state.

[0079] Through steps S202 to S206 above, lightning energy is detected, wherein the lightning energy is released at the antenna port; when the discharge tube is in the conducting state during the release of lightning energy, the shut-off device is controlled to block the formation of a short circuit between the negative busbar and the positive busbar of the power supply system, wherein the short circuit current is formed by the discharge tube being in the conducting state or the freewheeling state; when the discharge tube is in the freewheeling state after the release of lightning energy, the shut-off device is controlled to shut off the discharge tube based on the short circuit current. In other words, this embodiment triggers the discharge tube to conduct through lightning energy. When the discharge tube is in the conducting state during the release of lightning energy, a shut-off device connected between the signal ground of the power system and the negative busbar of the power system blocks the short-circuit current formed between the negative busbar and the positive busbar of the power system. Alternatively, when the discharge tube is in the freewheeling state after the release of lightning energy, the shut-off device shuts off the discharge tube based on the short-circuit current. This achieves timely shut-off of the discharge tube to protect the devices in the power system from damage, thereby achieving the purpose of protecting the signal of the power system. This solves the technical problem that devices in the power system are easily damaged when and after the protection circuit is triggered, thus achieving the technical effect of protecting the devices in the power system.

[0080] The method described in this embodiment will be further described below.

[0081] As an optional implementation, during the process where the lightning energy triggers the discharge tube to be in the conducting state, the residual voltage of the lightning energy at the antenna port is lower than the target threshold.

[0082] In this embodiment, when the lightning energy triggers the discharge tube to conduct, it is necessary to ensure that the residual voltage of the lightning energy at the antenna port is lower than the target threshold. When lightning energy is detected, the lightning energy can be released at the antenna port. At this time, a residual voltage will be generated at the antenna port after the lightning energy is released. It is necessary to ensure that the residual voltage at the antenna port is as low as possible, so as not to cause damage to downstream devices during lightning strikes due to raising the residual voltage of the lightning protection circuit. Optionally, the residual voltage in this embodiment is the residual voltage caused by the absence of other superimposed protective devices.

[0083] Optionally, the target threshold in this embodiment can be preset. The target threshold can be the voltage value at which the signal protection circuit of the power supply system will not be damaged by lightning strikes and the residual voltage is minimized.

[0084] As an optional implementation, the shut-off device is a thermistor, and the shut-off device based on the short-circuit current controls the discharge tube to turn off, including: triggering the thermistor to change from a low impedance state to a high impedance state by the short-circuit current; and turning off the discharge tube by the thermistor in the high impedance state.

[0085] In this embodiment, the shutdown device can be a thermistor. After a short-circuit current is generated between the negative busbar and the positive busbar of the power system, the thermistor can be triggered by the short-circuit current to enter a high-impedance state from a low-impedance state, and then the discharge tube can be shut off by the thermistor in the high-impedance state.

[0086] Optionally, in this embodiment, when the power system is operating normally, since no current flows between the GND and negative busbar of the power system, the structure of the aforementioned thermistor is very small, close to a short circuit, thus not affecting other functional performance of the power system. When the power system is subjected to external lightning strike energy, the discharge tube discharges, resulting in a large short-circuit current between the positive and negative busbars. This short-circuit current flows through the aforementioned thermistor, causing the thermistor to heat up and generate instantaneous impedance. This causes the thermistor to change from a low impedance state to a high impedance state in a short time. The thermistor in the high impedance state prevents the discharge tube from continuing to discharge, thus the discharge tube can be turned off by the high-configuration thermistor.

[0087] Optionally, the thermistor in this embodiment can be a PTC thermistor.

[0088] Optionally, the type of the thermistor in this embodiment can be determined according to the actual application.

[0089] As an optional implementation, the holding current of the thermistor is greater than the current flowing through the thermistor when the power supply system is in normal operating condition; the switching current of the thermistor is less than the minimum current among the multiple maximum operating currents corresponding to multiple components in the power supply system.

[0090] In this embodiment, no current flows during normal operation of the power supply system, so the holding current of the thermistor can be selected to be very small. Under normal circumstances, however, the holding current of the thermistor needs to be greater than the current flowing during normal operation, while the switching current of the thermistor needs to be less than the minimum maximum current that all devices in the loop can withstand, thereby ensuring that the thermistor can operate in a low-impedance state during normal operation.

[0091] As an optional implementation, the thermistor is triggered to change from a low impedance state to a high impedance state by a short-circuit current, including: triggering the thermistor to change from a low impedance state to a high impedance state by a short-circuit current before each component reaches its corresponding maximum operating current.

[0092] In this embodiment, after the lightning-triggered discharge tube discharges, the thermistor can be triggered from a low impedance state to a high impedance state by the short-circuit current generated on the negative and positive busbars of the power supply system before each device reaches its maximum operating current, thereby achieving the purpose of protecting the components in the power supply system from damage.

[0093] As an optional implementation, the method further includes: determining that the thermistor is in a low-impedance state when the current flowing through the thermistor is less than the holding current; and determining that the thermistor is in a high-impedance state when the current flowing through the thermistor is greater than the switching current.

[0094] In this embodiment, when the current flowing through the thermistor during normal operation is less than the thermistor's holding current, it can be ensured that the thermistor operates in a low-impedance state during normal operation. Conversely, when the current flowing through the thermistor during normal operation is greater than the thermistor's holding current, it is determined that the thermistor is in a high-impedance state.

[0095] As an alternative implementation, no current flows between the signal ground and the negative busbar when the thermistor is in a low impedance state, or the current flowing through it is lower than the switching current of the thermistor.

[0096] In this embodiment, when the thermistor is in a low impedance state, the power supply system is in normal working condition. At this time, no current flows between the signal ground and the negative busbar, or the current flowing between them is lower than the switching current of the thermistor. As long as the thermistor is not triggered when the equipment is working normally, it is fine.

[0097] Alternatively, in this embodiment, when there is no current flowing between the ground terminal and the negative busbar, the holding current of the thermistor can be selected to be a very small value.

[0098] As an optional implementation, the shut-off device is a circuit breaker, and the shut-off device is shut down based on the short-circuit current control, including: triggering the circuit breaker to work by the short-circuit current to block the formation of a short-circuit loop between the negative busbar and the positive busbar of the power system during the release of lightning energy, or shutting down the discharge tube after the release of lightning energy.

[0099] In this embodiment, the shut-off device can be a circuit breaker. When a short-circuit current is generated between the negative busbar and the positive busbar of the power system, the short-circuit current can trigger the circuit breaker to work. That is, during the release of lightning energy, the circuit breaker is triggered to block the formation of a short-circuit loop between the negative busbar and the positive busbar of the power system, or after the release of lightning energy, the circuit breaker is triggered to shut off the discharge tube, thereby achieving the purpose of protecting equipment or devices.

[0100] Optionally, the circuit breaker in this embodiment can be a smart circuit breaker.

[0101] The signal protection method for the power system in this embodiment triggers the discharge tube to conduct through lightning energy. When the discharge tube is in the conducting state during the release of lightning energy, a shut-off device connected between the signal ground and the negative busbar of the power system blocks the short-circuit current formed between the negative and positive busbars of the power system. Alternatively, when the discharge tube is in the freewheeling state after the release of lightning energy, the shut-off device shuts off the discharge tube based on the short-circuit current. This achieves timely shut-off of the discharge tube to protect the devices in the power system from damage, thereby achieving the purpose of protecting the signal of the power system. This solves the technical problem that devices in the power system are easily damaged when and after the protection circuit is triggered, thus achieving the technical effect of protecting the devices in the power system.

[0102] Example 3

[0103] The signal protection circuit of the power supply system of the present invention will be further described below with reference to preferred embodiments.

[0104] In related technologies, to reduce the monitoring design cost of power systems, save PCB space, and improve the accuracy of bus voltage sampling, the grounding terminal GND and the negative bus of the power system are connected in a non-isolated manner, while the positive bus of the power system is connected to PE (0V). If the RF signal antenna port is directly protected by a gas discharge tube, the gas discharge tube between the common-mode protection PE and the power system GND is essentially directly connected between the positive and negative bus (maximum 60VDC). This can lead to a short circuit if the gas discharge tube is triggered by lightning energy and discharges, the bus voltage prevents it from being turned off in time, resulting in damage to the components of the power system. Furthermore, in some cases, such as the protection of the DC bus output port, the problem of the discharge tube's freewheeling shutdown can be solved by adding a varistor in series to the discharge tube. However, this design increases the lightning residual voltage at the protected port, which can easily damage the port components, especially for lightning-sensitive antenna ports.

[0105] Figure 3 This is a schematic diagram of a signal protection circuit for a power supply system based on related technologies. For example... Figure 3 As shown, the signal protection circuit of the power supply system includes: positive busbar 30, negative busbar 31, GND 32, ground wire 33, discharge tube 34 (shown as 34A and 34B in the figure), filter circuit 35 (shown as 35A and 35B in the figure), wireless communication module 36, and single-board auxiliary power supply circuit 37.

[0106] In this embodiment, after the discharge tube 34A is triggered to discharge, the discharge tube 34A cannot be turned off because there is a power supply voltage between the positive busbar and the negative busbar, which will cause damage to the components in the circuit.

[0107] In the above embodiment, GND32 is the signal ground of the power system, and ground line 33 is the system grounding terminal.

[0108] In the above embodiment, the filter circuit 35A can be an RF matching filter circuit.

[0109] In the above embodiment, the single-board auxiliary power circuit 37 can provide voltage to the wireless communication module 36.

[0110] In the aforementioned technologies, after the gas discharge tube is triggered to discharge by lightning energy, the bus voltage prevents the discharge tube from being shut off in time, thus forming a short circuit. This leads to the problem of burning out the components of the power supply system. Furthermore, the residual voltage of the protection port due to lightning strikes will also increase, which can easily damage the port components, especially for lightning-sensitive antenna ports.

[0111] The signal protection circuit of the power system in this application is triggered by lightning energy to turn on the discharge tube. When the discharge tube is in the conducting state during the release of lightning energy, the short-circuit current formed between the negative bus and the positive bus of the power system is blocked by the shutdown device connected between the signal ground of the power system and the negative bus of the power system. Alternatively, when the discharge tube is in the freewheeling state after the release of lightning energy, the shutdown device turns off the discharge tube based on the short-circuit current. This achieves timely shutdown of the discharge tube to protect the devices in the power system from damage, thereby achieving the purpose of protecting the signal of the power system.

[0112] Figure 4 This is a schematic diagram of a signal protection circuit for another power supply system according to an embodiment of the present invention. Figure 4 As shown, the signal protection circuit of the power supply system may include: positive busbar 40, negative busbar 41, GND 42, ground wire 43, discharge tube 44 (shown as 44A and 44B in the figure), filter circuit 45 (shown as 45A and 45B in the figure), wireless communication module 46, single-board auxiliary power supply circuit 47, and thermistor 48.

[0113] In this embodiment, a filter circuit for improving EMC performance is provided between GND42 and negative busbar 41 of the power supply system, and a thermistor 48 is connected in series. During normal operation, no current flows between GND42 and negative busbar 41 of the power supply system. The resistance value of the thermistor 48 is very small, close to a short circuit, so it does not affect other functional performance of the power supply system.

[0114] In the above embodiment, GND42 is the signal ground of the power system, and ground wire 43 is the system grounding terminal.

[0115] In this embodiment, when the external lightning strike energy triggers the discharge tube 44A to discharge (conduct), the power supply voltage between the positive busbar 40 and the negative busbar 41 will form a large short-circuit current in the circuit for a short time through the freewheeling discharge tube. This current flows through the thermistor 48, causing the thermistor 48 to heat up and generate instantaneous impedance, which quickly rises to a high impedance state. The positive busbar 40 and the negative busbar 41 are separated by the thermistor 48 in a high impedance state, and a short-circuit loop cannot be formed, thereby protecting the power supply system.

[0116] In this embodiment, after the lightning strike energy dissipates, the high-impedance thermistor 48 prevents the discharge tube from continuing to carry current, thus turning off the discharge tube. After the discharge tube turns off, thermistor 48 quickly returns to its initial low-impedance state due to the lack of current flow, and the power supply system also returns to its initial normal operating state. At the same time, during the lightning strike, the residual voltage at the antenna port of the power supply system is also at its lowest, and this residual voltage can be the residual voltage caused by the absence of other protective devices.

[0117] In this embodiment, the selection of the thermistor 48 can be determined according to the actual application. Generally, the holding current Ih of the thermistor 48 needs to be greater than the current flowing during normal operation, while the switching current It needs to be less than the minimum value of the maximum current that all devices in the loop circuit can withstand. This ensures that the thermistor 48 can work in a low impedance state during normal operation. After the lightning strike triggers the discharge tube to conduct and discharge, the thermistor 48 will enter a high impedance state before the device reaches the maximum operating current, thereby achieving the purpose of protecting the components in the power supply system from damage.

[0118] In the above embodiment, the thermistor 48 is placed between GND42 and negative busbar 41. The connection between the two is only to provide a unified reference for sampling analog quantities such as the power supply voltage between positive busbar 40 and negative busbar 41. No current flows during normal operation, so the holding current Ih can be selected as a very small value.

[0119] For example, in this embodiment, the thermistor 48 preferably has an Ih of 0.14A and an It of 0.34A. That is, when the current Ih is below 0.14A, the thermistor 48 can operate in a normal low-impedance state. When Ih is greater than 0.34A of It, the thermistor 48 will change from a low-impedance state to a protective high-impedance state.

[0120] It should be noted that in this embodiment, the thermistor 48 is located to the right of the filter circuit 45B.

[0121] Figure 5 This is a schematic diagram of a signal protection circuit for a power supply system according to another embodiment of the present invention. Figure 5As shown, the signal protection circuit of the power supply system may include: positive busbar 50, negative busbar 51, GND 52, ground wire 53, discharge tube 54 (shown as 54A and 54B in the figure), filter circuit 55 (shown as 55A and 55B in the figure), wireless communication module 56, single-board auxiliary power supply circuit 57, and thermistor 58.

[0122] The scheme of this embodiment is similar to Figure 4 The solution is similar to that in the previous example. However, in this embodiment, the thermistor 58 is positioned to the left of the filter circuit 55B, that is, in the auxiliary power supply circuit of the single board. In this case, when selecting the thermistor 58, it is necessary to consider that the reserved current Ih is greater than the maximum operating current required by the power supply system under normal conditions.

[0123] In the above embodiment, GND52 is the signal ground of the power system, and ground wire 53 is the system grounding terminal.

[0124] In this embodiment, the power system will experience a brief power outage and reset when struck by lightning. This is mainly because when the lightning strikes, the circuit triggers the thermistor 58 to enter a high impedance state, which shuts off the power supply in the single-board auxiliary power circuit 57, resulting in a momentary power outage. After the lightning strike, once the discharge tube's freewheeling current is turned off, the thermistor 58 will return to its initial low impedance state, and the power system will return to normal power supply.

[0125] In this embodiment, the auxiliary power supply circuit of the single board may include a filter circuit 55A, a wireless communication module 56, and a single board auxiliary power supply circuit 57.

[0126] It should be noted that the position of the thermistor in this embodiment can be anywhere on the path from GND to the negative busbar, and the thermistor can be a PTC thermistor.

[0127] The signal protection circuit for the power supply system in this application can prevent short circuits and damage to the power supply system even if the gas discharge tube is triggered and turned on, and it also does not increase the residual voltage problem caused by lightning strikes at the port, thus solving the problem of lightning protection for high-frequency wireless signal antennas in such communication power supply systems. Furthermore, the signal protection method for the power supply system in this application can be widely applied to the protection of high-frequency sensitive signals in similar power supply systems.

[0128] Example 4

[0129] According to an embodiment of the present invention, a signal protection device for a power supply system is also provided. It should be noted that this signal protection device for a power supply system can be used to perform the signal protection method for a power supply system described in Embodiment 2.

[0130] Figure 6 This is a schematic diagram of a signal protection device for a power supply system according to an embodiment of the present invention. Figure 6 As shown, the signal protection device 60 of the power supply system may include: a detection unit 61, a first control unit 62, and a second control unit 63.

[0131] The detection unit 61 is used to detect lightning strike energy, wherein the lightning strike energy is released at the antenna port.

[0132] The first control unit 62 is used to control the shutdown device to block the short-circuit current formed between the negative busbar and the positive busbar of the power supply system when the trigger discharge tube is in the conducting state during the release of lightning energy. The short-circuit current is formed by the discharge tube being in the conducting state or the freewheeling state.

[0133] The second control unit 63 is used to shut off the discharge tube based on the short-circuit current control shutdown device when the discharge tube is in the freewheeling state after the lightning energy is released.

[0134] The signal protection device of the power system in this embodiment is triggered by lightning energy to turn on the discharge tube. When the discharge tube is in the conducting state during the release of lightning energy, the short-circuit current formed between the negative bus and the positive bus of the power system is blocked by a shut-off device connected between the signal ground and the negative bus of the power system. Alternatively, when the discharge tube is in the freewheeling state after the release of lightning energy, the shut-off device turns off the discharge tube based on the short-circuit current. This achieves timely shutdown of the discharge tube to protect the devices in the power system from damage, thereby achieving the purpose of protecting the signal of the power system. This solves the technical problem that devices in the power system are easily damaged when and after the protection circuit is triggered, and achieves the technical effect of protecting the devices in the power system.

[0135] Example 5

[0136] According to an embodiment of the present invention, a computer-readable storage medium is also provided, the computer-readable storage medium including a stored program, wherein the program executes the signal protection method of the power system described in Embodiment 2.

[0137] Example 6

[0138] According to an embodiment of the present invention, a processor is also provided for running a program, wherein the program is executed by the processor to perform the signal protection method of the power system described in Embodiment 2.

[0139] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0140] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0141] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0142] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0143] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0144] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or 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 personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0145] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A signal protection circuit for a power supply system, characterized in that, include: A discharge tube is used to be turned on by lightning energy, so that the lightning energy is released at the antenna port; A shutdown device is connected between the signal ground of the power system and the negative busbar of the power system to block the short-circuit current formed between the negative busbar and the positive busbar of the power system, or to shut off the discharge tube based on the short-circuit current. The shutdown device includes: a thermistor connected in series with the power system's filter circuit between the signal ground and the negative busbar; When a short-circuit current is formed between the negative busbar and the positive busbar, the short-circuit current triggers the thermistor to change from a low impedance state to a high impedance state. The thermistor in the high impedance state blocks the short-circuit current or turns off the discharge tube.

2. The circuit according to claim 1, characterized in that, The protection circuit includes: The antenna port is connected to the discharge tube and the transmitting antenna.

3. The circuit according to claim 1, characterized in that, The thermistor is disposed in the target circuit, which includes the positive busbar and the negative busbar, and includes a circuit other than the circuit formed by the signal ground, the discharge tube and the system ground terminal.

4. The circuit according to claim 1, characterized in that, The thermistor is disposed in the power supply circuit of the power supply system, the power supply circuit is disposed in the target circuit, and the power supply circuit is a single board power supply circuit.

5. The circuit according to claim 1, characterized in that, The shutdown device includes: A circuit breaker, connected to the discharge tube, is used to interrupt the short-circuit current formed between the negative busbar and the positive busbar by being triggered by the short-circuit current, and to prevent the discharge tube from entering the freewheeling state after the lightning energy is released.

6. A signal protection method for a power supply system, applied to the signal protection circuit of the power supply system according to any one of claims 1 to 5, characterized in that, The method includes: Detecting lightning strike energy, wherein the lightning strike energy is released at the antenna port; During the release of lightning energy, when the discharge tube is triggered to be in the conducting state, the control shutdown device blocks the formation of a short-circuit current between the negative busbar and the positive busbar of the power system. The short-circuit current is formed by the discharge tube being in the conducting state or the freewheeling state. After the lightning strike energy is released, when the discharge tube is in the freewheeling state, the shut-off device is controlled to shut off the discharge tube based on the short-circuit current.

7. The method according to claim 6, characterized in that, During the process of the lightning strike energy triggering the discharge tube to enter the conducting state, the residual voltage of the lightning strike energy at the antenna port is lower than the target threshold.

8. The method according to claim 6, characterized in that, The shut-off device is a thermistor, and the shut-off device is controlled to shut off the discharge tube based on the short-circuit current, including: The short-circuit current triggers the thermistor to change from a low-impedance state to a high-impedance state; The discharge tube is turned off by the thermistor, which is in the high-impedance state.

9. The method according to claim 8, characterized in that, The holding current of the thermistor is greater than the current flowing through the thermistor when the power supply system is in normal operating condition; the switching current of the thermistor is less than the minimum current among the multiple maximum operating currents corresponding to multiple components in the power supply system.

10. The method according to claim 9, characterized in that, Triggering the thermistor from a low-impedance state to a high-impedance state by the short-circuit current includes: Before each of the components reaches its corresponding maximum operating current, the thermistor is triggered by the short-circuit current to transition from the low impedance state to the high impedance state.

11. The method according to claim 9, characterized in that, The method further includes: When the current flowing through the thermistor is less than the holding current, the thermistor is determined to be in the low impedance state. When the current flowing through the thermistor is greater than the switching current, the thermistor is determined to be in the high impedance state.

12. The method according to claim 8, characterized in that, When the thermistor is in the low impedance state, no current flows between the signal ground and the negative busbar, or the current flowing through is lower than the switching current of the thermistor.

13. The method according to claim 6, characterized in that, The shut-off device is a circuit breaker, and the shut-off device is controlled to shut off the discharge tube based on the short-circuit current, including: The circuit breaker is triggered by the short-circuit current to prevent a short circuit from forming between the negative and positive busbars of the power system during the release of lightning energy, or to shut off the discharge tube after the release of lightning energy.

14. A signal protection device for a power supply system, applied to the signal protection circuit of the power supply system according to any one of claims 1 to 5, characterized in that, include: A detection unit is used to detect lightning strike energy, wherein the lightning strike energy is released at the antenna port; The first control unit is configured to, during the release of lightning energy, when the discharge tube is triggered to be in the conducting state, control the shutdown device to block the short-circuit current formed between the negative busbar and the positive busbar of the power system, wherein the short-circuit current is formed by the discharge tube being in the conducting state or the freewheeling state. The second control unit is used to control the shutdown device to shut off the discharge tube based on the short-circuit current when the discharge tube is in the freewheeling state after the lightning energy is released.

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