Overvoltage protection circuit, control method, power supply circuit and electric equipment

Abstract

The invention discloses an overvoltage protection circuit, a control method, a power supply circuit and electric equipment. The overvoltage protection circuit comprises a voltage detection module, the first input end of the voltage detection module is connected with the positive terminal of the input end of the power supply circuit, the second input end of the voltage detection module is connected with the negative terminal of the input end of the power supply circuit, and the voltage detection module is used for detecting the voltage of the input end of the power supply circuit; the protection module is arranged between the input end of the power supply circuit and the output end of the power supply circuit; the input end of the controller is connected with the voltage detection module, the output end of the controller is connected with the protection module, and the controller is used for controlling the connection state of the protection module to change when the voltage of the input end of the power supply circuit exceeds a first protection threshold value. And the ratio of the voltage of the output end of the power supply circuit to the voltage of the input end of the power supply circuit is controlled to be reduced. According to the power supply circuit, overvoltage protection can be carried out under the condition of uninterruptible power supply, and the reliability and the safety of the power supply circuit are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and in particular to an overvoltage protection circuit, a control method, a power supply circuit and an electrical device. Background Art

[0002] Existing electrical equipment has unstable input power during operation. If the voltage of the input power is too high, the system will first cut off the power circuit to protect the components in the circuit, and then re-power it on when the power voltage fluctuates within a suitable range. However, re-powering on after power failure can easily cause the voltage across the charging resistor to suddenly increase, thereby burning the charging resistor.

[0003] With regard to the problem in the prior art that when the power supply circuit is powered on again after being powered off due to overvoltage, the voltage across the charging resistor may suddenly increase, thereby burning the charging resistor, no effective solution has been proposed yet. Summary of the invention

[0004] An overvoltage protection circuit, a control method, a power supply circuit and an electrical device are provided in the embodiments of the present invention to solve the problem in the prior art that when the power supply circuit is powered on again after being powered off due to overvoltage, the voltage across the charging resistor may suddenly increase, thereby burning the charging resistor.

[0005] In order to solve the above technical problems, the present invention provides an overvoltage protection circuit, which is applied to a power supply circuit. A charging resistor and a charging switch connected in parallel are arranged between the negative terminal of the input end and the positive terminal of the output end of the power supply circuit. The overvoltage protection circuit includes:

[0006] A voltage detection module, a first input end of which is connected to the positive terminal of the input end of the power circuit, and a second input end of which is connected to the negative terminal of the input end of the power circuit, for detecting the voltage of the input end of the power circuit;

[0007] A protection module, arranged between the input end of the power circuit and the output end of the power circuit;

[0008] A controller, whose input end is connected to the voltage detection module and whose output end is connected to the protection module, is used to control the connection state of the protection module to change when the voltage at the input end of the power supply circuit exceeds a first protection threshold, thereby controlling the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end to decrease.

[0009] Furthermore, the protection module includes:

[0010] A first resistor and a second resistor are arranged in series, the first resistor is connected to the positive terminal of the input end of the power circuit, the second resistor is connected to the negative terminal of the input end of the power circuit, and a lead line between the first resistor and the second resistor is connected to the positive terminal of the output end of the power circuit;

[0011] A first switch, a first end of which is connected to the positive terminal of the input end of the power circuit, a second end of which is connected to the positive terminal of the output end of the power circuit, and a control end of which is connected to the controller;

[0012] The controller is used to control the first switch in the protection module to be disconnected when the voltage at the input end of the power supply circuit exceeds a first protection threshold, thereby controlling the first resistor in the protection module to be turned on, thereby reducing the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end.

[0013] Furthermore, the first resistor and the second resistor satisfy the following relationship:

[0014] R2 / (R1+R2)≤first protection threshold / Umax;

[0015] Wherein, Umax is the maximum value of the voltage at the input end of the power supply circuit, R1 is the first resistor, and R2 is the second resistor.

[0016] Furthermore, the overvoltage protection circuit further includes:

[0017] A photoelectric coupler is arranged between the controller and the control end of the first switch.

[0018] Furthermore, the voltage detection module includes:

[0019] An operational amplifier, wherein the in-phase input terminal thereof is connected to the positive terminal of the input terminal of the power supply circuit via a third resistor, the in-phase input terminal thereof is connected to the negative terminal of the input terminal of the power supply circuit via a fourth resistor, the in-phase input terminal thereof is also grounded via a fifth resistor and a first capacitor connected in parallel, the output terminal thereof is connected to its own in-phase input terminal via a sixth resistor and a second capacitor connected in parallel, and the output terminal thereof is also connected to the controller.

[0020] Furthermore, the overvoltage protection circuit further includes:

[0021] a second switch, disposed between a negative terminal of an input end of the power circuit and a negative terminal of an output end of the power circuit;

[0022] The controller is further configured to control the second switch and the charging switch to be disconnected in sequence when the voltage at the input end of the power supply circuit exceeds a second protection threshold.

[0023] The present invention also provides a power supply circuit, comprising the above-mentioned overvoltage protection circuit.

[0024] The present invention also provides an electrical device, comprising the power supply circuit.

[0025] Furthermore, the electrical equipment includes at least one of the following: an air conditioner, a refrigerator, and a washing machine.

[0026] The present invention also provides an overvoltage protection control method, which is applied to the above-mentioned overvoltage protection circuit. The overvoltage protection control method includes:

[0027] Determining whether the voltage at the input end of the power supply circuit exceeds a first protection threshold;

[0028] If yes, the ratio between the voltage at the output terminal and the voltage at the input terminal of the power supply circuit is controlled to decrease.

[0029] Further, controlling the ratio between the voltage at the output end and the voltage at the input end of the power supply circuit to decrease comprises:

[0030] The first switch in the protection module is controlled to be disconnected, thereby controlling the first resistor in the protection module to be turned on, thereby reducing the ratio between the voltage at the output end and the voltage at the input end of the power supply circuit.

[0031] Furthermore, the method further comprises:

[0032] Determining whether the voltage at the input end of the power supply circuit exceeds a second protection threshold; wherein the second protection threshold is greater than the first protection threshold;

[0033] If yes, the second switch and the charging switch are controlled to be turned off in sequence.

[0034] The present invention also provides a computer-readable storage medium having a computer program stored thereon, characterized in that the above-mentioned overvoltage protection control method is implemented when the program is executed by a processor.

[0035] The present invention also provides an electronic device, comprising:

[0036] one or more processors;

[0037] A storage device is used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned overvoltage protection control method.

[0038] By applying the technical solution of the present invention, the voltage of the input end of the power supply circuit is obtained through the voltage detection module. When the voltage of the input end of the power supply circuit exceeds the first protection threshold, the controller controls the connection state of the protection module to change, thereby controlling the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end to decrease. When the voltage of the input end remains unchanged, the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end decreases, and the voltage of the output end of the power supply circuit also decreases, thereby reducing the voltage of the load connected to the output side of the power supply circuit, thereby realizing overvoltage protection without power failure, avoiding the problem that the voltage of the charging resistor suddenly increases when the power supply circuit is powered on again after overvoltage power failure, thereby burning the charging resistor, and improving the reliability and safety of the power supply circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a structural diagram of an overvoltage protection circuit according to an embodiment of the present invention;

[0040] Figure 2 is a schematic diagram of the connection relationship between the photoelectric coupler, the controller and the first switch according to an embodiment of the present invention;

[0041] Figure 3 is a flow chart of an overvoltage protection control method according to an embodiment of the present invention;

[0042] Figure 4 FIG. 4 is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0045] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0046] It should be understood that although the terms first, second, third, etc. may be used to describe resistors in embodiments of the present invention, these resistors should not be limited to these terms. These terms are only used to distinguish different resistors. For example, without departing from the scope of embodiments of the present invention, a first resistor may also be referred to as a second resistor, and similarly, a second resistor may also be referred to as a first resistor.

[0047] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0048] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0049] The optional embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0050] Example 1

[0051] Existing electrical equipment has unstable input power during operation. If the voltage of the input power is too high, the system will first cut off the power circuit to protect the components in the circuit, and then power on again when the power voltage fluctuates within a suitable range. However, powering on again after power failure can easily cause the voltage across the charging resistor to suddenly increase, thereby burning the charging resistor.

[0052] In view of the problem in the prior art that the voltage across the charging resistor may suddenly increase when the power supply circuit is powered on again after being powered off due to overvoltage, thereby burning the charging resistor, this embodiment provides an overvoltage protection circuit, which is applied to the power supply circuit. A charging resistor R0 and a charging switch S0 connected in parallel are arranged between the negative terminal of the input end and the positive terminal of the output end of the power supply circuit, and a supporting capacitor C0 is arranged between the positive terminal of the output end and the negative terminal of the output end of the power supply circuit. Figure 1 is a structural diagram of an overvoltage protection circuit according to an embodiment of the present invention, such as Figure 1 As shown, the above-mentioned overvoltage protection circuit includes:

[0053] A voltage detection module 10, whose first input end is connected to the positive terminal of the input end of the power supply circuit, and whose second input end is connected to the negative terminal of the input end of the power supply circuit, is used to detect the voltage of the input end of the power supply circuit; a protection module 20 is arranged between the input end of the power supply circuit and the output end of the power supply circuit; a controller 30, whose input end is connected to the voltage detection module 10, and whose output end is connected to the protection module 20, is used to control the connection state of the protection module to change when the voltage of the input end of the power supply circuit exceeds the first protection threshold, thereby controlling the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end to decrease, and when the voltage of the input end remains unchanged, the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end decreases, and the voltage of the output end of the power supply circuit also decreases. When the voltage of the input end of the power supply circuit does not exceed the first protection threshold, the connection state of the control protection module remains unchanged, thereby keeping the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end unchanged.

[0054] The overvoltage protection circuit of this embodiment obtains the voltage of the input end of the power supply circuit through the voltage detection module 10. When the voltage of the input end of the power supply circuit exceeds the first protection threshold, the controller 30 controls the connection state of the protection module to change, thereby controlling the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end to decrease. When the voltage of the input end remains unchanged, the ratio between the voltage of the output end of the power supply circuit and the voltage of the input end decreases, and the voltage of the output end of the power supply circuit also decreases, thereby reducing the voltage of the load connected to the output side of the power supply circuit, thereby realizing overvoltage protection without power failure, avoiding the problem that the voltage of the charging resistor suddenly increases when the power supply circuit is powered on again after an overvoltage power failure, thereby burning the charging resistor, and improving the reliability and safety of the power supply circuit.

[0055] In order to change the ratio between the voltage at the output end and the voltage at the input end of the power supply circuit, such as Figure 1 As shown, the protection module 20 includes: a first resistor R1 and a second resistor R2 arranged in series, the first resistor R1 is connected to the positive terminal of the input end of the power supply circuit, the second resistor R2 is connected to the negative terminal of the input end of the power supply circuit, and a lead line between the first resistor R1 and the second resistor R2 is connected to the positive terminal of the output end of the power supply circuit; a first switch Q1, whose first end (drain D) is connected to the positive terminal of the input end of the power supply circuit, and whose second end (source S) is connected to the positive terminal of the output end of the power supply circuit, and whose control end (gate G) is connected to the controller 30. When the voltage at the input end of the power supply circuit exceeds the first protection threshold, the controller 30 controls the first switch Q1 to be disconnected, thereby controlling the first resistor R1 in the protection module 20 to be turned on, so that the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end is reduced.

[0056] As mentioned above Figure 1 As shown in FIG. 1 , the first switch Q1 and the first resistor R1 are equivalent to being connected in parallel between the positive terminal of the input end of the power supply circuit and the positive terminal of the output end of the power supply circuit. When the first switch Q1 is turned on, the first resistor R1 is short-circuited, and the current does not flow through the first resistor R1, but flows through the first switch Q1 and the second resistor R2 in sequence. After the first switch Q1 is turned on, the voltage between the first end and the second end thereof can be ignored. Therefore, after the first switch Q1 is turned on, the voltage across the supporting capacitor is equal to the voltage across the second resistor R2, that is, the voltage at the output end of the power supply circuit is equal to the voltage at the input end of the power supply circuit, that is, the voltage at the output end of the power supply circuit is equal to the voltage at the input end of the power supply circuit. When the first switch Q1 is turned off, the first resistor R1 is no longer short-circuited, and current flows through the first resistor R1 and the second resistor R2 in sequence. Therefore, after the first switch Q1 is turned on, the voltage across the supporting capacitor is equal to the voltage across the second resistor R2, and the sum of the voltage across the second resistor R2 and the voltage across the first resistor R1 is equal to the voltage at the output end of the power supply circuit. Therefore, the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end is equal to R2 / (R1+R2). Since R2 and R1 are both positive values, the above ratio is significantly less than 1. Therefore, the voltage at the output end of the power supply circuit is reduced.

[0057] In order to ensure that the output voltage of the power supply circuit is below the safety threshold, the first resistor R1 and the second resistor R2 satisfy the following relationship: R2 / (R1+R2)≤first protection threshold / Umax; wherein Umax is the maximum value of the voltage at the input end of the power supply circuit.

[0058] Since the voltage output by the controller 30 may not match the control voltage of the first switch Q1, and thus the on-off of the switch cannot be accurately controlled, the on-off of the first switch Q1 can be controlled by isolating the output terminal of the controller from the control terminal of the first switch Q1. Figure 1 As shown, the above-mentioned overvoltage protection circuit further includes: a photocoupler OC, which is arranged between the controller 30 and the control end of the first switch Q1.

[0059] Figure 2 Schematic diagram of the connection relationship between the photoelectric coupler, the controller and the first switch according to an embodiment of the present invention. Figure 2 As shown, the anode of the light-emitting diode on the input side of the photocoupler OC is connected to the controller 30, the anode of the light-emitting diode is grounded, the first end of the output side of the photocoupler OC is connected to a +17V voltage, the second end of the output side of the photocoupler OC is connected to a -7V voltage, and the third end of the output side of the photocoupler OC is connected to the control end (gate G) and the second end (source S) of the first switch Q1.

[0060] In order to collect the voltage at the input of the power supply circuit, Figure 1As shown, the voltage detection module 10 includes: an operational amplifier U1, whose in-phase input terminal is connected to the positive terminal of the input terminal of the power supply circuit through the third resistor R3, whose in-phase input terminal is connected to the negative terminal of the input terminal of the power supply circuit through the fourth resistor R4, whose in-phase input terminal is also grounded through the fifth resistor R5 and the first capacitor C1 connected in parallel, whose output terminal is connected to its own in-phase input terminal through the sixth resistor R6 and the second capacitor C2 connected in parallel, and whose output terminal is also connected to the controller 30.

[0061] If the voltage at the input end of the power supply circuit further increases on the basis of the first protection threshold, the power supply circuit needs to be disconnected for safety reasons. Figure 1 As shown, the above-mentioned overvoltage protection circuit also includes: a second switch S1, which is arranged between the negative terminal of the input end of the power supply circuit and the negative terminal of the output end of the power supply circuit. Because after the charging switch S0 is disconnected, the charging resistor R0 will be turned on, and due to the overvoltage state, the charging resistor R0 will be damaged. In order to avoid the above situation, when the voltage at the input end of the power supply circuit exceeds the second protection threshold, the controller 30 controls the second switch S1 and the charging switch S0 to be disconnected in sequence, that is, the second switch S1 is disconnected first, and then the charging switch S0 is disconnected.

[0062] In summary, the specific working process of the overvoltage protection circuit of this embodiment is as follows:

[0063] After the voltage detection circuit detects that the power supply voltage value reaches the voltage threshold for starting the load, the controller 30 first controls the first switch Q1 to be disconnected and the charging switch S0 to be disconnected through the photocoupler, and then controls the second switch S1 to be closed, and the charging resistor R0 starts to work. When the voltage of the supporting capacitor C0 reaches the working voltage of the load, the pre-charge is completed, and the charging switch S0 is controlled to be closed. At this time, the output current flows through the charging switch S0 and the first switch Q1 and is output from the supporting capacitor C0, and the circuit works normally. When the voltage detection module 10 detects that the voltage at the input end of the power supply circuit exceeds the first protection threshold, but does not exceed the second protection threshold, the controller 30 controls the first switch Q1 to be turned off through the photocoupler, and the output current is changed from flowing through the first switch Q1 and then outputting through the supporting capacitor C0 to flowing through the first resistor R1 and the second resistor R2 and then outputting through the supporting capacitor C0. The voltage at the output end of the power supply circuit is R2 / (R1+R2) times the voltage at the input end of the power supply circuit, and the voltage at the output end of the power supply circuit is reduced, and the circuit continues to work without powering off.

[0064] When the voltage detection circuit detects that the power supply voltage is over-voltage and exceeds the above-mentioned second protection threshold, the controller 30 controls the second switch S1 to be disconnected first, and then controls the charging switch S0 to be disconnected, so as to prevent the output circuit from not being disconnected during the time interval when the charging switch S0 is disconnected first and the second switch S1 is not disconnected, and the output current burns the charging resistor R0.

[0065] Example 2

[0066] The present embodiment provides a power supply circuit, including the overvoltage protection circuit of the above embodiment, which is used to implement overvoltage protection without cutting off the power supply, so as to avoid the problem that the voltage across the charging resistor suddenly increases when the power supply circuit is powered on again after being cut off by overvoltage, thereby burning the charging resistor, thereby improving the reliability and safety of the power supply circuit.

[0067] Example 3

[0068] This embodiment provides an electrical device, including the power supply circuit of the above embodiment.

[0069] In some embodiments of the present invention, the electrical equipment includes at least one of the following: an air conditioner, a refrigerator, and a washing machine.

[0070] Example 4

[0071] This embodiment provides an overvoltage protection control method, which is applied to the overvoltage protection circuit of the above embodiment. Figure 3 : is a flow chart of an overvoltage protection control method according to an embodiment of the present invention. Figure 3 As shown, the above overvoltage protection control method includes:

[0072] S101, determining whether a voltage at an input terminal of a power supply circuit exceeds a first protection threshold.

[0073] S102: If yes, the ratio between the voltage at the output terminal and the voltage at the input terminal of the power supply circuit is controlled to decrease.

[0074] When the voltage at the input end remains unchanged, the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end decreases, and the voltage at the output end of the power supply circuit also decreases.

[0075] S103, if not, the ratio between the voltage at the output end and the voltage at the input end of the control power supply circuit remains unchanged.

[0076] The overvoltage protection control method of this embodiment controls the ratio of the voltage at the output end of the power supply circuit to the voltage at the input end to decrease when the voltage at the input end of the power supply circuit exceeds the first protection threshold value. When the voltage at the input end remains unchanged, the ratio of the voltage at the output end of the power supply circuit to the voltage at the input end decreases, and the voltage at the output end of the power supply circuit also decreases, thereby reducing the voltage of the load connected to the output side of the power supply circuit, thereby achieving overvoltage protection without power failure, avoiding the problem that the voltage at both ends of the charging resistor suddenly increases when the power supply circuit is powered on again after an overvoltage power failure, thereby burning the charging resistor, and improving the reliability and safety of the power supply circuit.

[0077] As described above, in order to change the ratio between the voltage at the output end and the voltage at the input end of the power supply circuit, as Figure 1 As shown, the protection module 20 includes: a first resistor R1 and a second resistor R2 arranged in series, the first resistor R1 is connected to the positive terminal of the input end of the power supply circuit, the second resistor R2 is connected to the negative terminal of the input end of the power supply circuit, and a lead line between the first resistor R1 and the second resistor R2 is connected to the positive terminal of the output end of the power supply circuit; a first switch Q1, a first end of which is connected to the positive terminal of the input end of the power supply circuit, a second end of which is connected to the positive terminal of the output end of the power supply circuit, and a control end of which is connected to the controller 30, so that the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end is controlled to decrease, including: controlling the first switch Q1 to be disconnected, thereby controlling the first resistor R1 in the protection module to be turned on, thereby reducing the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end.

[0078] As mentioned above Figure 1 As shown in FIG. 1 , the first switch Q1 and the first resistor R1 are equivalent to being connected in parallel between the positive terminal of the input end of the power supply circuit and the positive terminal of the output end of the power supply circuit. When the first switch Q1 is turned on, the first resistor R1 is short-circuited, and the current does not flow through the first resistor R1, but flows through the first switch Q1 and the second resistor R2 in sequence. After the first switch Q1 is turned on, the voltage between the first end and the second end thereof can be ignored. Therefore, after the first switch Q1 is turned on, the voltage across the supporting capacitor is equal to the voltage across the second resistor R2, that is, the voltage at the output end of the power supply circuit is equal to the voltage at the input end of the power supply circuit, that is, the voltage at the output end of the power supply circuit is equal to the voltage at the input end of the power supply circuit. When the first switch Q1 is turned off, the first resistor R1 is no longer short-circuited, and current flows through the first resistor R1 and the second resistor R2 in sequence. Therefore, after the first switch Q1 is turned on, the voltage across the supporting capacitor is equal to the voltage across the second resistor R2, and the sum of the voltage across the second resistor R2 and the voltage across the first resistor R1 is equal to the voltage at the output end of the power supply circuit. Therefore, the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end is equal to R2 / (R1+R2). Since R2 and R1 are both positive values, the above ratio is significantly less than 1. Therefore, the voltage at the output end of the power supply circuit is reduced.

[0079] If the voltage at the input end of the power supply circuit further increases on the basis of the first protection threshold, for safety reasons, the above-mentioned overvoltage protection circuit also includes: a second switch S1, which is arranged between the negative terminal of the input end of the power supply circuit and the negative terminal of the output end of the power supply circuit. Because after the charging switch S0 is disconnected, the charging resistor R0 will be turned on, and due to the overvoltage state, the charging resistor R0 will be damaged. In order to avoid the above situation, the above-mentioned overvoltage protection control method also includes: judging whether the voltage at the input end of the power supply circuit exceeds the second protection threshold (i.e., the absolute overvoltage value); wherein the second protection threshold is greater than the first protection threshold; if yes, the second switch S1 and the charging switch S0 are controlled to be disconnected in sequence; if not, the second switch S1 and the charging switch S0 are controlled to remain turned on.

[0080] Example 5

[0081] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned overvoltage protection control method is implemented.

[0082] Example 6

[0083] This embodiment provides an electronic device, including:

[0084] one or more processors;

[0085] A storage device is used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned overvoltage protection control method.

[0086] Figure 4 FIG. 1 is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Figure 4 As shown, the electronic device includes:

[0087] One or more processors 410 and memory 420, Figure 4 A processor 410 is taken as an example.

[0088] The electronic device may further include: an input device 430 and an output device 440 .

[0089] The processor 410, the memory 420, the input device 430 and the output device 440 may be connected via a bus or other means. Figure 4 The example of connecting through bus is taken in the following.

[0090] The memory 420, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer executable programs and modules, such as program instructions / modules corresponding to the overvoltage protection control method in the embodiment of the present invention. The processor 410 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions and modules stored in the memory 420, that is, the local magnification method based on the editable document in the above method embodiment is realized.

[0091] The memory 420 may include a program storage area and a data storage area, wherein the program storage area may store an application required for operating the device and at least one function; the data storage area may store data created according to the use of the overvoltage protection control method, etc. In addition, the memory 420 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage devices.

[0092] The input device 430 can receive input digital or character information and generate key signal input related to user settings and function control of the electronic device. The output device 440 can include a display device such as a display screen.

[0093] The one or more modules are stored in the memory 420, and when executed by the one or more processors 410, the overvoltage protection control method in any of the above method embodiments is executed.

[0094] The electronic device can execute the method provided by the embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not described in detail in this embodiment, please refer to the method provided by the embodiment of the present invention.

[0095] The electronic device of the embodiment of the present invention exists in various forms, including but not limited to:

[0096] (1) Mobile communication devices: These devices are characterized by their mobile communication functions and their main purpose is to provide voice and data communications. These terminals include: smart phones (such as iPhone), multimedia phones, functional phones, and low-end phones.

[0097] (2) Ultra-mobile personal computer devices: These devices fall into the category of personal computers, have computing and processing capabilities, and generally also have mobile Internet access features. These terminals include: PDA, MID and UMPC devices, such as iPad.

[0098] (3) Portable entertainment devices: These devices can display and play multimedia content. They include audio and video players (such as iPods), handheld game consoles, e-books, smart toys, and portable car navigation devices.

[0099] (4) Server: A device that provides computing services. The server consists of a processor, hard disk, memory, device bus, etc. The server is similar to the general computer architecture, but because it needs to provide highly reliable services, it has higher requirements in terms of processing power, stability, reliability, security, scalability, manageability, etc.

[0100] (5) Other electronic devices with data interaction functions, such as televisions, large-screen cars, etc.

[0101] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0102] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An overvoltage protection circuit is applied to a power supply circuit, wherein a charging resistor and a charging switch are arranged in parallel between a negative terminal of an input end and a positive terminal of an output end of the power supply circuit, wherein: The overvoltage protection circuit comprises: a voltage detection module, a first input end of which is connected to the positive terminal of the input end of the power circuit, and a second input end of which is connected to the negative terminal of the input end of the power circuit, for detecting the voltage of the input end of the power circuit; A protection module, arranged between the input end of the power circuit and the output end of the power circuit; A controller, whose input end is connected to the voltage detection module and whose output end is connected to the protection module, is used to control the connection state of the protection module to change when the voltage at the input end of the power supply circuit exceeds a first protection threshold, thereby controlling the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end to decrease.

2. The overvoltage protection circuit according to claim 1, characterized in that: The protection module comprises: A first resistor and a second resistor are arranged in series, the first resistor is connected to the positive terminal of the input end of the power supply circuit, the second resistor is connected to the negative terminal of the input end of the power supply circuit, and a lead line between the first resistor and the second resistor is connected to the positive terminal of the output end of the power supply circuit; A first switch, a first end of which is connected to the positive terminal of the input end of the power circuit, a second end of which is connected to the positive terminal of the output end of the power circuit, and a control end of which is connected to the controller; The controller is used to control the first switch in the protection module to be disconnected when the voltage at the input end of the power supply circuit exceeds a first protection threshold, thereby controlling the first resistor in the protection module to be turned on, thereby reducing the ratio between the voltage at the output end of the power supply circuit and the voltage at the input end.

3. The overvoltage protection circuit according to claim 1, characterized in that: The first resistor and the second resistor satisfy the following relationship: R2 / (R1+R2)≤first protection threshold / Umax; Wherein, Umax is the maximum value of the voltage at the input end of the power supply circuit, R1 is the first resistor, and R2 is the second resistor.

4. The overvoltage protection circuit according to claim 2, characterized in that: The overvoltage protection circuit further includes: A photoelectric coupler is arranged between the controller and the control end of the first switch.

5. The overvoltage protection circuit according to claim 1, characterized in that: The voltage detection module comprises: An operational amplifier, wherein the in-phase input terminal thereof is connected to the positive terminal of the input terminal of the power supply circuit via a third resistor, the in-phase input terminal thereof is connected to the negative terminal of the input terminal of the power supply circuit via a fourth resistor, the in-phase input terminal thereof is also grounded via a fifth resistor and a first capacitor connected in parallel, the output terminal thereof is connected to its own in-phase input terminal via a sixth resistor and a second capacitor connected in parallel, and the output terminal thereof is also connected to the controller.

6. The overvoltage protection circuit according to claim 1, characterized in that: The overvoltage protection circuit further includes: a second switch, disposed between a negative terminal of an input end of the power circuit and a negative terminal of an output end of the power circuit; The controller is further configured to control the second switch and the charging switch to be disconnected in sequence when the voltage at the input end of the power supply circuit exceeds a second protection threshold.

7. A power supply circuit, characterized in that: The invention comprises the overvoltage protection circuit according to any one of claims 1 to 6.

8. An electrical device, characterized in that: Comprising the power supply circuit as claimed in claim 7.

9. The electrical equipment according to claim 8, characterized in that: The electrical equipment includes at least one of the following: an air conditioner, a refrigerator, and a washing machine.

10. An overvoltage protection control method, applied to the overvoltage protection circuit according to any one of claims 1 to 6, characterized in that: The method comprises: Determining whether the voltage at the input end of the power supply circuit exceeds a first protection threshold; If yes, the ratio between the voltage at the output terminal and the voltage at the input terminal of the power supply circuit is controlled to decrease.

11. The method according to claim 10, characterized in that Controlling the ratio between the voltage at the output end and the voltage at the input end of the power supply circuit to decrease comprises: The first switch in the protection module is controlled to be disconnected, thereby controlling the first resistor in the protection module to be turned on, thereby reducing the ratio between the voltage at the output end and the voltage at the input end of the power supply circuit.

12. The method according to claim 10, characterized in that The method further comprises: Determining whether the voltage at the input end of the power supply circuit exceeds a second protection threshold; wherein the second protection threshold is greater than the first protection threshold; If yes, the second switch and the charging switch are controlled to be turned off in sequence.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 10 to 12 is implemented.

14. An electronic device, characterized in that: include: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the one or more processors to implement the method according to any one of claims 10 to 12.

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