Surge Protection Method, Device, Protection Circuit, and Storage Medium

Abstract

The present invention provides a surge protection method and device, a protection circuit, and a storage medium, wherein the protection circuit includes: a first fuse unit, a protection unit, a unidirectional conductive unit, an energy storage unit, and an energy storage discharge unit, wherein the first fuse unit and the unidirectional conductive unit are respectively connected to the positive electrode of a power supply, and the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conductive unit and the energy storage unit are connected in series, the energy storage discharge unit is connected in parallel at the energy storage unit, and the power supply and the MOS transistor are connected in series; when the input voltage is normal voltage, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive, and the MOS transistor operates at normal voltage; when the input voltage is a positive surge, the first fuse unit and the protection unit are conductive; the unidirectional conductive unit and the energy storage unit are not conductive; when the input voltage is a negative surge, the first fuse unit and the protection unit are not conductive; and the unidirectional conductive unit and the energy storage unit are conductive.

Description

Technical Field

[0001] The present invention relates to the field of communication power supply equipment, and in particular to a surge protection method and device, a protection circuit, and a storage medium. Background Art

[0002] In communications equipment, system components are powered by a DC power supply. Metal oxide semiconductor field effect transistors (MOSFETs), also known as MOS transistors, are typically used to turn the DC power supply on and off. Because the DC power supply must be protected against reverse polarity, the MOSFET must also implement reverse polarity protection. Furthermore, the DC power supply typically uses an external capacitor, so the MOSFET must implement a slow start. This slow start allows the MOSFET to slowly turn on, charging the capacitor and ensuring reliable MOSFET startup.

[0003] When lightning strikes naturally, the lightning strike or the induced lightning surge generated by the lightning strike will directly be applied to the anti-reverse MOS tube and slow-start MOS tube on the DC power supply. Since the energy generated by the lightning surge is very large, excessive lightning surge energy will damage the MOS tube. Therefore, the DC power supply must have lightning surge protection to protect the anti-reverse MOS tube and slow-start MOS tube from damage.

[0004] There are currently two common solutions for protecting anti-reverse MOSFETs and slow-start MOSFETs from damage:

[0005] Option 1: If Figure 1 As shown, the DC power supply input end is provided with single-stage protection and the MOS tube is provided with protection:

[0006] When a lightning surge is applied to the DC power supply, due to the high energy and peak voltage of the lightning surge, it exceeds the operating voltage of the transient voltage suppressor (TVS) (VD1 and VD2 in the figure). The protection devices VD1 and VD2 clamp and absorb the lightning surge energy, reducing the voltage of the anti-reverse MOS tube (ie Figure 1 VT1), slow start MOS tube (ie Figure 1 The spike voltage across VT2 is reduced to within the safe operating range of the MOS tube. Protective devices VD1 and VD2 provide protection during lightning surges, ensuring the normal operation of the MOS tube.

[0007] The input range of DC power supply is generally -36V to -72V. In this range, the DC power supply needs to work normally, but the protection components VD1 and VD2 cannot work. In this case, VD1 and VD2 can only use TVS with a voltage of 72V or above. However, when a lightning surge occurs in the DC power supply, the TVS clamping voltage is high and the residual voltage at both ends of the TVS is high, which makes the anti-reverse MOS tube (i.e. Figure 1 VT1) and slow-start MOS tube (ie Figure 1 In VT2), only MOS tubes above 200V can be selected. However, MOS tubes above 200V have problems such as large size, large internal resistance, high heat loss, high voltage resistance, and high cost.

[0008] Option 2: If Figure 2 As shown, the DC power supply input end is equipped with double-stage protection and the MOS is equipped with protection:

[0009] When a lightning surge is applied to the DC power supply, the surge energy is high and the peak voltage is high, which exceeds the protection device TVS (i.e. Figure 2 VD1, VD2), the action voltage of the varistor RV1, VD1, RV1, VD2 clamp and absorb the lightning surge energy, reducing the anti-reverse MOS tube (i.e. Figure 2 VT1), slow start MOS tube (ie Figure 2 The spike voltage at both ends of VT2 is reduced to the safe operating range of the MOS tube. VD1, RV1, and VD2 play a protective role in the event of a lightning surge, ensuring the normal operation of the MOS tube during a lightning surge.

[0010] The DC power supply generally has an input range of -36V to -72V. While the DC power supply must function properly within this range, the protective components VD1, RV1, and VD2 must not function. Therefore, VD1, VD2, and RV1 must use TVS and varistors with voltages exceeding 72V. When a lightning surge strikes the DC power supply, the clamping voltage of these TVS and varistors is high, forcing the use of MOSFETs with voltages exceeding 200V for both the anti-reverse MOSFET VT1 and the slow-start MOSFET VT2. However, MOSFETs with voltages exceeding 200V are bulky, have high internal resistance, high heat dissipation, high withstand voltage, and high cost.

[0011] Regarding the related art, in the event of a lightning surge, there is a problem that the residual voltage of the anti-reverse MOS tube and the slow-start MOS tube is high, and only anti-reverse MOS tubes and slow-start MOS tubes with high voltage resistance can be selected. No effective technical solution has been proposed yet. Summary of the Invention

[0012] Embodiments of the present invention provide a surge protection method and device, a protection circuit, and a storage medium to at least solve the problem in the related art that, in the event of a lightning surge, the residual voltage of an anti-reverse MOS transistor and a slow-start MOS transistor is high, and only anti-reverse MOS transistors and slow-start MOS transistors with high voltage resistance can be selected.

[0013] According to one embodiment of the present invention, a protection circuit is provided, comprising a first fuse unit, a protection unit, a unidirectional conduction unit, an energy storage unit, and an energy storage discharge unit, wherein:

[0014] The first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel to the energy storage unit, and the power supply is connected in series with the MOS tube; wherein,

[0015] When the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage;

[0016] When the input voltage of the power supply is a positive surge voltage,

[0017] The first fuse unit is conductively connected to the protection unit; the unidirectional conductive unit is not conductively connected to the energy storage unit;

[0018] When the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; and the unidirectional conductive unit and the energy storage unit are conductive.

[0019] Optionally, the first fuse unit is conductively connected to the protection unit and the unidirectional conductive unit is not conductively connected to the energy storage unit, so that the forward surge voltage is clamped to a specified voltage, wherein the MOS transistor operates at the specified voltage.

[0020] Optionally, the first fuse unit is not conductive with the protection unit; the unidirectional conductive unit is conductive with the energy storage unit; so that the energy storage unit obtains part or all of the negative surge voltage.

[0021] Optionally, the energy storage discharge unit is further configured to discharge part or all of the negative surge voltage in the energy storage unit after a predetermined time.

[0022] Optionally, the protection circuit also includes: a second fuse unit, which is respectively connected to the negative pole of the power supply, the protection unit, and the energy storage unit, and is used to disconnect the second fuse unit when any of the following units is abnormal: the unidirectional conduction unit, the energy storage unit, and the energy storage discharge unit.

[0023] According to one embodiment of the present invention, a surge protection method is provided, which is applied to any of the protection circuits described above. The method includes:

[0024] When the voltage inputted by the power supply to the protection circuit is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage;

[0025] When the voltage inputted by the power supply to the protection circuit is a forward surge voltage, the first fuse unit is connected to the protection unit; and the unidirectional conductive unit is not connected to the energy storage unit.

[0026] When the voltage input from the power supply to the protection circuit is a negative surge voltage, the first fuse unit and the protection unit are not conductive; and the unidirectional conductive unit and the energy storage unit are conductive.

[0027] Optionally, when the first fuse unit is conductive with the protection unit and the unidirectional conductive unit is not conductive with the energy storage unit, the forward surge voltage is clamped to a specified voltage, wherein the MOS transistor operates at the specified voltage.

[0028] Optionally, when the first fuse unit and the protection unit are not conductive and the unidirectional conductive unit and the energy storage unit are conductive, part or all of the negative surge voltage is obtained through the energy storage unit, and after a predetermined time, part or all of the negative surge voltage is discharged through the energy storage discharge unit to enable the MOS tube to work normally.

[0029] According to another embodiment of the present invention, a surge protection device is provided, which is applied to the protection circuit, and the device includes:

[0030] a first processing module, configured to, when the voltage inputted by the power supply to the protection circuit is the normal voltage of the power supply, disconnect the first fuse unit from the protection unit, disconnect the unidirectional conductive unit from the energy storage unit, and enable the MOS transistor to operate at the normal voltage;

[0031] a second processing module, configured to, when the voltage inputted by the power supply to the protection circuit is a forward surge voltage, connect the first fuse unit to the protection unit, and disconnect the unidirectional conductive unit from the energy storage unit;

[0032] The third processing module is configured to disconnect the first fuse unit from the protection unit and connect the unidirectional conductive unit to the energy storage unit when the voltage input from the power supply to the protection circuit is a negative surge voltage.

[0033] According to yet another embodiment of the present invention, a storage medium is provided, in which a computer program is stored. The computer program is configured to execute the steps of any one of the above method embodiments when running.

[0034] According to another embodiment of the present invention, an electronic device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to perform the steps in any one of the above method embodiments.

[0035] According to the present invention, the first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel at the energy storage unit, and the power supply is connected in series with the MOS transistor; wherein, when the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are not conductive; the MOS transistor operates at the normal voltage; when the input voltage of the power supply is a positive surge voltage, the first fuse unit and the protection unit are conductive; the unidirectional conduction unit and the energy storage unit are not conductive; when the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are conductive. The present invention solves the problem in the related art that, in the event of a lightning surge, the residual voltage of the anti-reverse MOS tube and the slow-start MOS tube is high, and only the anti-reverse MOS tube and the slow-start MOS tube with high voltage resistance can be selected. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0037] Figure 1 This is a circuit diagram of a lightning surge protection solution in the prior art;

[0038] Figure 2 This is a circuit diagram of another lightning surge protection solution in the prior art;

[0039] Figure 3 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention;

[0040] Figure 4 is a circuit diagram of another protection circuit according to an optional embodiment of the present invention;

[0041] Figure 5 is a flow chart of a surge protection method according to an optional embodiment of the present invention;

[0042] Figure 6 is a circuit diagram of another protection circuit according to an optional embodiment of the present invention;

[0043] Figure 7 is a structural block diagram of a surge protection device according to an optional embodiment of the present invention;

[0044] Figure 8 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (I);

[0045] Figure 9 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (II);

[0046] Figure 10 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (III);

[0047] Figure 11 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (four);

[0048] Figure 12 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (V);

[0049] Figure 13 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (six);

[0050] Figure 14 7 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention;

[0051] Figure 15 8 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention;

[0052] Figure 16 1 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention (IX);

[0053] Figure 17 10 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention;

[0054] Figure 18 FIG11 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention. DETAILED DESCRIPTION

[0055] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other.

[0056] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0057] Example 1

[0058] In this embodiment, a protection circuit is provided. Figure 3 is a circuit diagram of a protection circuit according to an optional embodiment of the present invention, such as Figure 3 As shown, the protection circuit includes the following units: a first fuse unit, a protection unit, a unidirectional conduction unit, an energy storage unit and an energy storage discharge unit, wherein:

[0059] The first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel to the energy storage unit, and the power supply is connected in series with the MOS tube; wherein,

[0060] When the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage;

[0061] When the input voltage of the power supply is a forward surge voltage, the first fuse unit is connected to the protection unit; the unidirectional conductive unit is not connected to the energy storage unit;

[0062] When the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; and the unidirectional conductive unit and the energy storage unit are conductive.

[0063] According to the present invention, the first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel at the energy storage unit, and the power supply is connected in series with the MOS transistor; wherein, when the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are not conductive; the MOS transistor operates at the normal voltage; when the input voltage of the power supply is a positive surge voltage, the first fuse unit and the protection unit are conductive; the unidirectional conduction unit and the energy storage unit are not conductive; when the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are conductive. The present invention solves the problem in the related art that, in the event of a lightning surge, the residual voltage of the anti-reverse MOS tube and the slow-start MOS tube is high, and only the anti-reverse MOS tube and the slow-start MOS tube with high voltage resistance can be selected.

[0064] Optionally, the first fuse unit is conductively connected to the protection unit and the unidirectional conductive unit is not conductively connected to the energy storage unit, so that the forward surge voltage is clamped to a specified voltage, wherein the MOS transistor operates at the specified voltage.

[0065] Optionally, the first fuse unit is not conductive with the protection unit; the unidirectional conductive unit is conductive with the energy storage unit; so that the energy storage unit obtains part or all of the negative surge voltage.

[0066] Optionally, the energy storage discharge unit is further configured to discharge part or all of the negative surge voltage in the energy storage unit after a predetermined time.

[0067] Optionally, Figure 4 FIG. 1 is a circuit diagram of another protection circuit according to an optional embodiment of the present invention. Figure 4 As shown, the protection circuit further includes:

[0068] The second fuse unit is connected to the negative electrode of the power supply, the protection unit, and the energy storage unit respectively, and is used to disconnect the second fuse unit when any of the following units is abnormal: the one-way conduction unit, the energy storage unit, and the energy storage discharge unit.

[0069] In an embodiment of the present invention, when the power input is at a normal voltage, which may be -36V to -72V, the first fuse unit connected in series with the protection unit is not conductive, and the unidirectional conductive unit connected in series with the energy storage unit is also not conductive. At this point, the second fuse unit operates at a normal voltage. That is, when the subsequent circuit (i.e., the anti-reverse MOSFET and the slow-start MOSFET) is connected after the second fuse unit, the subsequent circuit can also operate at a normal voltage.

[0070] In this embodiment of the present invention, when a forward surge is applied between the positive and negative power supply electrodes, the first fuse unit, connected in series with the protection unit, conducts, while the unidirectional conduction unit, connected in series with the energy storage unit, becomes non-conductive. The input forward surge forms a surge relief circuit through the conducting first fuse unit and the protection unit. The protection unit clamps the input forward surge to a certain voltage (i.e., reduces the forward surge to a certain voltage), allowing subsequent circuits (i.e., the subsequently connected anti-reverse MOSFET and slow-start MOSFET) to operate at a normal, safe voltage.

[0071] In an embodiment of the present invention, when a negative surge is applied between the positive and negative poles of the power supply, the first fuse unit connected in series with the protection unit is non-conductive, and the unidirectional conduction unit connected in series with the energy storage unit is conductive. The negative surge is conducted through the unidirectional conduction unit connected in series with the energy storage unit to form a surge discharge circuit, and the energy storage unit begins to store energy, storing part or all of the negative surge energy in the energy storage unit, so that the subsequent circuit (i.e., the subsequently connected anti-reverse MOS tube and slow-start MOS tube) operates at a normal safety voltage. The energy storage discharge unit discharges energy from the energy storage unit after the negative surge ends, and the energy storage unit continues to store energy when the next negative surge is input. In addition, the second fuse unit also plays a protective role. When any of the conduction unit, the energy storage unit, and the energy storage discharge unit is abnormal, the second fuse unit is disconnected to protect the subsequent circuit (i.e., the subsequently connected anti-reverse MOS tube and slow-start MOS tube).

[0072] Example 2

[0073] In this embodiment, a surge protection method is provided, which is applied to the above protection circuit. Figure 4 : is a flow chart of a surge protection method according to an optional embodiment of the present invention. Figure 4 As shown, the process includes the following steps:

[0074] Step S402: When the voltage inputted by the power supply to the protection circuit is the normal voltage of the power supply, the first fuse unit and the protection unit are disconnected; the unidirectional conductive unit and the energy storage unit are disconnected; and the MOS transistor operates at the normal voltage.

[0075] Step S404: when the voltage inputted by the power supply to the protection circuit is a forward surge voltage, the first fuse unit is connected to the protection unit; and the unidirectional conducting unit is disconnected from the energy storage unit.

[0076] Step S406 , when the voltage inputted by the power supply to the protection circuit is a negative surge voltage, the first fuse unit and the protection unit are disconnected; and the unidirectional conductive unit and the energy storage unit are connected.

[0077] According to the present invention, the first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel at the energy storage unit, and the power supply is connected in series with the MOS transistor; wherein, when the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are not conductive; the MOS transistor operates at the normal voltage; when the input voltage of the power supply is a positive surge voltage, the first fuse unit and the protection unit are conductive; the unidirectional conduction unit and the energy storage unit are not conductive; when the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are conductive. The present invention solves the problem in the related art that, in the event of a lightning surge, the residual voltage of the anti-reverse MOS tube and the slow-start MOS tube is high, and only the anti-reverse MOS tube and the slow-start MOS tube with high voltage resistance can be selected.

[0078] Optionally, when the first fuse unit is conductive with the protection unit and the unidirectional conductive unit is not conductive with the energy storage unit, the forward surge voltage is clamped to a specified voltage, wherein the MOS transistor operates at the specified voltage.

[0079] Optionally, when the first fuse unit and the protection unit are not conductive and the unidirectional conductive unit and the energy storage unit are conductive, part or all of the negative surge voltage is obtained through the energy storage unit, and after a predetermined time, part or all of the negative surge voltage is discharged through the energy storage discharge unit to enable the MOS tube to work normally.

[0080] Example 3

[0081] This embodiment also provides a surge protection device for use with the aforementioned protection circuit. The device is used to implement the aforementioned embodiments and preferred implementations, and details already described will not be repeated. As used below, the term "module" may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0082] Figure 5 is a structural block diagram of a surge protection device according to an optional embodiment of the present invention, such as Figure 5 As shown, the device includes:

[0083] A first processing module 52 is configured to, when the voltage inputted by the power supply to the protection circuit is the normal voltage of the power supply, disconnect the first fuse unit from the protection unit, disconnect the unidirectional conductive unit from the energy storage unit, and enable the MOS transistor to operate at the normal voltage;

[0084] A second processing module 54 is configured to, when the voltage inputted by the power supply to the protection circuit is a forward surge voltage, connect the first fuse unit to the protection unit, and disconnect the unidirectional conductive unit from the energy storage unit;

[0085] The third processing module 56 is configured to disconnect the first fuse unit from the protection unit and connect the unidirectional conductive unit to the energy storage unit when the voltage input from the power supply to the protection circuit is a negative surge voltage.

[0086] Through the above modules, the first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel at the energy storage unit, and the power supply and the MOS transistor are connected in series; wherein, when the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are not conductive; the MOS transistor operates at the normal voltage; when the input voltage of the power supply is a positive surge voltage, the first fuse unit and the protection unit are conductive; the unidirectional conduction unit and the energy storage unit are not conductive; when the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; the unidirectional conduction unit and the energy storage unit are conductive. The present invention solves the problem in the related art that, in the event of a lightning surge, the residual voltage of the anti-reverse MOS tube and the slow-start MOS tube is high, and only the anti-reverse MOS tube and the slow-start MOS tube with high voltage resistance can be selected.

[0087] Optionally, the second processing module 54 is further used to clamp the forward surge voltage to a specified voltage when the first fuse unit and the protection unit are conductive and the unidirectional conductive unit and the energy storage unit are not conductive, wherein the MOS tube operates at the specified voltage.

[0088] Optionally, the third processing module 56 is further configured to, when the first fuse unit and the protection unit are not conductive and the unidirectional conductive unit and the energy storage unit are conductive, obtain part or all of the negative surge voltage through the energy storage unit, and discharge part or all of the negative surge voltage through the energy storage discharge unit after a predetermined time, so as to enable the MOS tube to operate normally.

[0089] It should be noted that the above modules can be implemented through software or hardware. For the latter, it can be implemented in the following ways, but not limited to: the above modules are all located in the same processor; or the above modules are located in different processors in any combination.

[0090] The above technical solution is described below in conjunction with preferred embodiments, but is not intended to limit the technical solution of the embodiments of the present invention.

[0091] Preferred embodiment 1. Figure 6 As shown, Figure 6 is a circuit diagram of another protection circuit according to an optional embodiment of the present invention, such as Figure 6 As shown, it includes: fuse FU1, protection device FV1 (ie, a TVS), diode D1, capacitor C1 and resistor R1, wherein,

[0092] When the power input is normal voltage (such as -36V to -72V), FV1 is not conductive through the FU1 fuse, and there is no voltage across the capacitor C1. Then the subsequent circuit (i.e., the anti-reverse MOS tube and the slow-start MOS tube) can operate at normal voltage.

[0093] When a forward surge is applied between the positive and negative power supply terminals, protection unit FV1 conducts through fuse FU1. The forward surge passes through the conducting fuse FU1 and protection unit FV1, forming a surge discharge circuit. This allows protection unit FV1 to clamp the forward surge to a certain voltage. Furthermore, diode D1 is cut off at this point, and there is no voltage across capacitor C1. The subsequent circuitry (i.e., the anti-reverse MOSFET and the slow-start MOSFET) can then operate at this clamped voltage.

[0094] When a negative surge is applied between the positive and negative terminals of the power supply, capacitor C1 forms a current loop through diode D1 to absorb the negative surge energy. The negative surge is clamped at a lower operating voltage, allowing subsequent devices (i.e., the anti-reverse MOSFET and the slow-start MOSFET) to operate at a lower voltage. Resistor R1 discharges capacitor C1 after the negative surge ends, allowing capacitor C1 to absorb the surge energy again when the next negative surge occurs.

[0095] The diode can be a diode with a higher withstand voltage, such as a 200V diode. The capacitor C1 can be an electrolytic capacitor with a capacity greater than 300uF.

[0096] Through the above method, you can choose an anti-reverse MOS tube and a slow-start MOS tube with a lower working voltage, such as a 100V anti-reverse MOS tube and a slow-start MOS tube.

[0097] In summary, the above method solves the problem in the background technology that in solution 1 and solution 2, due to the high operating voltage of the protection device, only anti-reverse MOS tubes and slow-start MOS tubes with a voltage of more than 200V can be selected. In addition, the anti-reverse MOS tubes and slow-start MOS tubes with low operating voltage generate less heat, are small in size, low in cost, and highly reliable.

[0098] like Figures 8 to 18 FIG. 1 is a schematic diagram of several protection circuits according to an optional embodiment of the present invention.

[0099] Among them, FU1 and FU2 are fuses; FV1 and FV2 are TVS; C1 and C2 are electrolytic capacitors; R1 and R2 are resistors; D1 and D2 are diodes; VT1 and VT2 are MOS tubes.

[0100] It should be noted that:

[0101] like Figure 8 As shown in the figure, when a negative surge voltage occurs on the positive and negative inputs and the surge voltage exceeds the operating voltage of FV1, FV1 turns on, and the positive and negative inputs release energy through the series circuit composed of FV1 and FU1, reducing the negative surge residual voltage.

[0102] At the same time, a negative surge voltage occurring between the positive and negative inputs is also applied to the circuit formed by FU2, C1, R1, and D1. The negative surge charges C1 through FU2 and D1. Since C1 is a capacitor, the voltage across it cannot change suddenly, so the voltage on C1 can only rise slowly. Part of the energy of the negative surge voltage is absorbed by capacitor C1 and converted into capacitor energy. C1 absorbs the negative surge voltage energy, further reducing the residual surge voltage between the positive and negative inputs until it reaches the safe operating voltage of the device. After the negative surge voltage passes, capacitor C1 releases the energy through resistor R1, ensuring that capacitor C1 can effectively absorb the negative surge residual voltage before the next negative surge voltage occurs between the positive and negative inputs.

[0103] It should be noted that, compared to Figure 1 and Figure 2 In the circuit, FV1 and FU1 are a Figure 1 and Figure 2 The circuit has the same function, but C1, R1, and D1 are relative Figure 1 and Figure 2 The newly added circuit (also called the circuit core) absorbs most of the negative surge residual voltage due to the presence of C1 and D1, which controls the negative surge voltage between the positive input and the negative input to below 40V. Figure 1 and Figure 2 VT1 in) and slow-start MOS tube (such as Figure 1 and Figure 2 For VT2) in the figure, you can choose a MOS tube with a DS voltage less than 100V.

[0104] In summary, by adding circuits C1, R1, and D1, the anti-reverse MOS tube and the slow-start MOS tube can be reduced from selecting a DS voltage of 200V to selecting a MOS tube with a DS voltage of 100V. The 100V MOS tube has the advantages of smaller on-resistance, smaller size, and lower cost. Therefore, the 100V MOS tube has more competitive advantages.

[0105] like Figure 9 As shown, relative to Figure 8 , Figure 9 Will Figure 8 The diode D1 in the circuit is changed to FV2, and FV2 is connected to Figure 8 The role played by D1 in the circuit is the same, both are unidirectional conduction, and the conduction current can only flow from the negative input to the positive input.

[0106] like Figure 10 As shown, Figure 10 Relative to Figure 8 , Figure 10 Will Figure 8 The diode D1 in the circuit is changed to FV2, and FV2 is connected to Figure 8 The role played by D1 in the circuit is the same, both are unidirectional conduction, and the conduction current can only flow from the negative input to the positive input.

[0107] like Figure 11 As shown, Figure 11 Relative to Figure 8 FU2 has been removed, and the subsequent circuitry includes a reverse-phase protection MOSFET VT1 and a slow-start MOSFET VT2, along with an energy storage capacitor C2. The core circuitry consisting of C1, R1, and D1 remains unchanged. The newly added VT1 and VT2 have no effect on the negative surge absorption circuit. Devices following C1, R1, and D1 can have a DS voltage less than 100V. This is especially true when a negative surge voltage occurs on the positive and negative inputs.

[0108] like Figure 12 As shown, Figure 12 Relative to Figure 8 , FU2, FV1 and FU1 are removed, the circuit core C1, R1, D1 remain unchanged, and the negative surge protection function remains unchanged.

[0109] like Figure 13 As shown, Figure 13 Relative to Figure 8 , FU2 is removed, the circuit core C1, R1, and D1 remain unchanged, and the negative surge protection function remains unchanged.

[0110] like Figure 14 As shown, Figure 14 Relative to Figure 8 , FU2 is removed. FV1, C1, R1, and D1 share a fuse FU1 during negative surges, and the negative surge protection function remains unchanged.

[0111] like Figure 15 As shown, Figure 15 Relative to Figure 8 , FU2 is removed, Figure 15 Will Figure 8 The FV1 in the circuit is replaced with a varistor, but the negative surge protection function remains unchanged.

[0112] like Figure 16 As shown, Figure 16 Relative to Figure 8 , FU2 was removed. Figure 16 Will Figure 8 The diode D1 in the circuit is replaced with MOS transistor VT1. Since the MOS transistor has a parasitic diode, it also conducts in a unidirectional manner and has the same function as a diode. The negative surge protection function remains unchanged.

[0113] like Figure 17 As shown, Figure 17 Relative to Figure 8, FV1, FU1, and FU2 have been removed. Of the core circuit components C1, R1, and D1, R1 has been removed, leaving only C1 and D1. Negative surge protection remains unchanged. Without discharge resistor R1, capacitor C1 discharges more slowly. However, due to the equivalent discharge resistor within capacitor C1, the charge on capacitor C1 will be discharged, albeit at a slower rate.

[0114] like Figure 18 As shown, Figure 18 Relative to Figure 8 FU2 is removed and diode D2 is added. The core circuit C1, R1, and D1 are retained, and the negative surge protection function remains unchanged. In some cases, the power supply front-end input has its own overcurrent protection device, such as an air switch.

[0115] It should be noted that when a negative surge voltage occurs on the positive and negative inputs, Figure 9-18 How the circuit works can be referenced Figure 8 The implementation methods shown will not be described in detail here.

[0116] It should be noted that capacitors absorbing negative surges are not limited to capacitors, and other methods that can absorb negative surges are all within the scope of protection of the present invention. Diodes and capacitors forming a negative surge energy absorption circuit are not limited to diodes, and other methods that can form a negative surge energy absorption circuit with capacitors are all within the scope of protection of the present invention. TVS and insurance combined with diodes and capacitors to absorb positive and negative surges are not limited to TVS and insurance, and other circuit combinations of diodes and capacitors to absorb positive and negative surges are all within the scope of protection of the present invention.

[0117] Example 4

[0118] An embodiment of the present invention further provides a storage medium storing a computer program, wherein the computer program is configured to execute the steps of any of the above method embodiments when running.

[0119] Optionally, in this embodiment, the storage medium may be configured to store a computer program for performing the following steps:

[0120] S1, when the voltage of the power supply input to the protection circuit is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage;

[0121] S2, when the voltage inputted by the power supply to the protection circuit is a forward surge voltage, the first fuse unit is connected to the protection unit; and the unidirectional conductive unit is not connected to the energy storage unit;

[0122] S3, when the voltage inputted by the power supply to the protection circuit is a negative surge voltage, the first fuse unit and the protection unit are not conducted; and the unidirectional conducting unit and the energy storage unit are conducted.

[0123] Optionally, the storage medium is further configured to store a computer program for performing the following steps:

[0124] S1, clamping the forward surge voltage to a specified voltage when the first fuse unit is conductively connected to the protection unit and the unidirectional conductive unit is not conductively connected to the energy storage unit, wherein the MOS transistor operates at the specified voltage.

[0125] Optionally, the storage medium is further configured to store a computer program for performing the following steps:

[0126] S1, when the first fuse unit and the protection unit are not conductive and the unidirectional conductive unit and the energy storage unit are conductive, part or all of the negative surge voltage is obtained through the energy storage unit, and after a predetermined time, part or all of the negative surge voltage is discharged through the energy storage discharge unit to enable the MOS tube to work normally.

[0127] Optionally, in this embodiment, the above-mentioned storage medium may include but is not limited to: a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and other media that can store computer programs.

[0128] Example 5

[0129] An embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0130] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0131] Optionally, in this embodiment, the processor may be configured to execute the following steps through a computer program:

[0132] S1, when the voltage of the power supply input to the protection circuit is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage;

[0133] S2, when the voltage inputted by the power supply to the protection circuit is a forward surge voltage, the first fuse unit is connected to the protection unit; and the unidirectional conductive unit is not connected to the energy storage unit;

[0134] S3, when the voltage inputted by the power supply to the protection circuit is a negative surge voltage, the first fuse unit and the protection unit are not conducted; and the unidirectional conducting unit and the energy storage unit are conducted.

[0135] Optionally, specific examples in this embodiment may refer to the examples described in the above embodiments and optional implementation modes, and this embodiment will not be described in detail here.

[0136] Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented using a general-purpose computing device, centralized on a single computing device, or distributed across a network of multiple computing devices. Alternatively, they can be implemented using program code executable by a computing device, which can then be stored in a storage device and executed by the computing device. In some cases, the steps shown or described can be performed in a different order than that shown, or can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0137] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the principles of the present invention shall be considered within the protection threshold of the present invention.

Claims

1. A protection circuit, characterized in that: It includes a first fuse unit, a protection unit, a unidirectional conduction unit, an energy storage unit and an energy storage discharge unit, wherein: The first fuse unit and the unidirectional conduction unit are respectively connected to the positive electrode of the power supply, the protection unit and the energy storage unit are respectively connected to the negative electrode of the power supply, the first fuse unit and the protection unit are connected in series, the unidirectional conduction unit and the energy storage unit are connected in series, an energy storage discharge unit is connected in parallel to the energy storage unit, and the power supply is connected in series with the MOS tube; wherein, When the input voltage of the power supply is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage; When the input voltage of the power supply is a forward surge voltage, the first fuse unit is connected to the protection unit; the unidirectional conductive unit is not connected to the energy storage unit; When the input voltage of the power supply is a negative surge voltage, the first fuse unit and the protection unit are not conductive; and the unidirectional conductive unit and the energy storage unit are conductive.

2. The circuit according to claim 1, wherein: The first fuse unit is conductively connected to the protection unit, and the unidirectional conductive unit is not conductively connected to the energy storage unit, so that the forward surge voltage is clamped to a specified voltage, wherein the MOS transistor operates at the specified voltage.

3. The circuit according to claim 1, wherein: The first fuse unit is not conductive with the protection unit; the unidirectional conductive unit is conductive with the energy storage unit; so that the energy storage unit obtains part or all of the negative surge voltage.

4. The circuit according to claim 3, characterized in that The energy storage discharge unit is further configured to discharge part or all of the negative surge voltage in the energy storage unit after a predetermined time.

5. The circuit according to any one of claims 1 to 4, characterized in that The protection circuit also includes: a second fuse unit, which is respectively connected to the negative electrode of the power supply, the protection unit, and the energy storage unit, and is used to disconnect the second fuse unit when any unit among the one-way conduction unit, the energy storage unit, and the energy storage discharge unit is abnormal.

6. A surge protection method, characterized in that: Applied to the protection circuit according to any one of claims 1 to 5, the method comprises: When the voltage inputted by the power supply to the protection circuit is the normal voltage of the power supply, the first fuse unit and the protection unit are not conductive; the unidirectional conductive unit and the energy storage unit are not conductive; and the MOS transistor operates at the normal voltage; When the voltage inputted by the power supply to the protection circuit is a forward surge voltage, the first fuse unit is connected to the protection unit; and the unidirectional conductive unit is not connected to the energy storage unit. When the voltage input from the power supply to the protection circuit is a negative surge voltage, the first fuse unit and the protection unit are not conductive; and the unidirectional conductive unit and the energy storage unit are conductive.

7. The method according to claim 6, characterized in that The method further comprises: When the first fuse unit is conductively connected to the protection unit and the unidirectional conductive unit is not conductively connected to the energy storage unit, the forward surge voltage is clamped to a specified voltage, wherein the MOS transistor operates at the specified voltage.

8. The method according to claim 6, characterized in that The method further comprises: When the first fuse unit and the protection unit are not conductive and the unidirectional conductive unit and the energy storage unit are conductive, part or all of the negative surge voltage is obtained through the energy storage unit, and after a predetermined time, part or all of the negative surge voltage is discharged through the energy storage discharge unit to enable the MOS tube to operate normally.

9. A surge protection device, characterized in that: Applicable to the protection circuit according to any one of claims 1 to 5, the device comprising: a first processing module, configured to, when the voltage inputted by the power supply to the protection circuit is the normal voltage of the power supply, disconnect the first fuse unit from the protection unit, disconnect the unidirectional conductive unit from the energy storage unit, and enable the MOS transistor to operate at the normal voltage; a second processing module, configured to, when the voltage inputted by the power supply to the protection circuit is a forward surge voltage, connect the first fuse unit to the protection unit, and disconnect the unidirectional conductive unit from the energy storage unit; The third processing module is configured to disconnect the first fuse unit from the protection unit and connect the unidirectional conductive unit to the energy storage unit when the voltage input from the power supply to the protection circuit is a negative surge voltage.

10. A storage medium, characterized in that: The storage medium stores a computer program, wherein the computer program is configured to execute the method according to any one of claims 6 to 8 when executed.

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