A power input anti-reverse connection circuit, a power module and an electric device

Abstract

The application relates to a power input anti-reverse connection circuit, a power module and a power utilization device, which comprise the following steps: detecting the voltage size of a power supply through a voltage detection module; identifying the positive and negative poles of the power supply according to the voltage size through an identification module; controlling the opening and closing of elements in an electronic switch according to the identification result through a switching module; and making the current flow direction always enter from the positive pole of a load and flow out from the negative pole of the load by opening and closing the elements in the electronic switch, so that the positive and negative poles of the load always remain consistent, that is, no matter whether the positive and negative poles of the power supply are connected reversely, the positive pole of the load always corresponds to the positive pole of the power supply, and the negative pole of the load always corresponds to the negative pole of the power supply. According to the application, when the power supply is reversely connected, manual operation is not needed to change the positive and negative poles of the power supply, and the load can still normally work under the condition that the power supply is reversely connected.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power supply anti-reverse connection, in particular to a power supply input anti-reverse connection circuit, a power supply module and a power consumption device. BACKGROUND

[0002] In the use process of electrical equipment, it is necessary to provide power input, especially direct current connection. The positive and negative connection of the power supply will be reversed due to the mistake of the operator, which will cause damage to the equipment. The traditional anti-reverse connection utilizes the unidirectional conduction of the diode. When the positive connection is conducted, the equipment works. When the reverse connection is blocked, the equipment does not work, thereby achieving the protection effect. Once the reverse connection is adopted, the correct connection method needs to be manually operated. SUMMARY

[0003] Therefore, the purpose of the present application is to provide a power supply input anti-reverse connection circuit, a power supply module and a power consumption device, so as to solve the problem that in the prior art, when the positive and negative poles of the power supply are reversed, the positive and negative poles of the power supply must be manually changed, and the equipment can normally work.

[0004] According to a first aspect of the embodiment of the present application, a power supply input anti-reverse connection circuit is provided, comprising:

[0005] An electronic switch is arranged between the power supply interface and the load interface.

[0006] A voltage detection module, an identification module and a switching module are sequentially connected.

[0007] The input end of the voltage detection module is connected with the power supply interface, and the output end of the switching module is connected with the control end of the electronic switch.

[0008] The voltage detection module is used for detecting the voltage value of the external power supply of the power supply interface, the identification module is used for judging the positive and negative poles of the external power supply according to the voltage value, and the switching module is used for controlling the on-off of the electronic switch according to the positive and negative poles, so that when the power supply interface is blindly inserted with the external power supply, the power direction of the external power supply flowing to the positive and negative poles of the load remains unchanged.

[0009] Preferably, the electronic switch comprises:

[0010] Four unidirectional conduction switch elements, which are respectively arranged in two groups to form a first conduction branch and a second conduction branch.

[0011] The first conduction branch and the second conduction branch are connected in parallel between the positive and negative poles of the power supply and the load, and are respectively connected with the switching module.

[0012] The first conduction branch and the second conduction branch are connected in parallel between the positive and negative poles of the power supply and the load, and are respectively connected with the switching module.

[0013] Preferably, the first conducting branch includes:

[0014] The first switching element Q4 has its first pin connected to the switching module, its second pin connected to the first terminal P1 of the power supply, and its third pin connected to the positive terminal of the load.

[0015] The second switching element Q3 has its first pin connected to the switching module, its second pin connected to the negative terminal of the load, and its third pin connected to the second terminal P2 of the power supply.

[0016] Wherein, when the first switching element Q4 and the second switching element Q3 are both IGBT modules, the first pin is the gate, the second pin is the collector, and the third pin is the emitter;

[0017] When the first terminal P1 of the power supply is positive, the second terminal P2 of the power supply is negative, and when the first terminal P1 of the power supply is negative, the second terminal P2 of the power supply is positive.

[0018] Preferably, the second conducting branch includes:

[0019] The third switching element Q2 has its first pin connected to the switching module, its second pin connected to the negative terminal of the load, and its third pin connected to the first terminal P1 of the power supply.

[0020] The fourth switching element Q1 has its first pin connected to the switching module, its second pin connected to the second terminal P2 of the power supply, and its third pin connected to the positive terminal of the load.

[0021] When both the first switching element Q2 and the second switching element Q1 are IGBT modules, the first pin is the gate, the second pin is the collector, and the third pin is the emitter.

[0022] Preferably, the voltage detection module includes:

[0023] The first operational amplifier U1 has its non-inverting input connected to the second terminal P2 of the power supply, its inverting input connected to the first terminal P1 of the power supply, and its output connected to the identification module.

[0024] Preferably, the identification module includes:

[0025] The first comparator U2 has its input terminal connected to the output terminal of the first operational amplifier U1, and its output terminal connected to the switching module.

[0026] The first comparator U2 is used to compare the output voltage of the first operational amplifier U1 with the first reference voltage V1 of the first operational amplifier U1, and output a high-level signal or a low-level signal according to the comparison result.

[0027] Preferably, the switching module includes:

[0028] Tri-state gate U6, tri-state gate U7, inverter U5, first driving circuit and second driving circuit;

[0029] The output of the first comparator U2 is connected to the input of the tri-state gate U6 and the inverter U5 respectively. The output of the tri-state gate U6 is connected to the second driving circuit, which is used to control the opening and closing of the second conducting branch.

[0030] The output terminal of the inverter U5 is connected to the input terminal of the tri-state gate U7, and the output terminal of the tri-state gate U7 is connected to the first driving circuit, which is used to control the opening and closing of the first conducting branch.

[0031] Preferably, it further includes:

[0032] Overvoltage detection module,

[0033] The overvoltage detection module includes comparator U3 and comparator U4;

[0034] The negative pin of comparator U3 and the positive pin of comparator U4 are respectively connected to the output terminal of the first operational amplifier U1. The positive pin of comparator U3 is input to the third reference voltage V3, and the negative pin of comparator U4 is input to the second reference voltage V2.

[0035] The comparator U3 and comparator U4 together form a threshold comparator.

[0036] Preferably, it further includes:

[0037] Overcurrent detection module,

[0038] The overcurrent detection module includes a second operational amplifier U11, a comparator U9, and a comparator U10;

[0039] The non-inverting input terminal of the operational amplifier U11 is connected to the first terminal P1 of the power supply, and the inverting input terminal of the operational amplifier U11 is connected to the second terminal P2 of the power supply.

[0040] The output terminal of the operational amplifier U11 is connected to the negative terminal of comparator U9 and the positive terminal of comparator U10, respectively.

[0041] The positive pin of comparator U9 receives the third sampling current V6, and the negative pin of comparator U10 receives the second sampling current V5.

[0042] Preferably, it further includes:

[0043] Protection module: includes AND gate U8;

[0044] The input terminals of AND gate U8 are respectively connected to the output terminals of comparator U3, comparator U4, comparator U9 and comparator U10;

[0045] The output of AND gate U8 is connected to the inputs of tri-state gate U6 and tri-state gate U7, respectively.

[0046] According to a second aspect of the present invention, a power supply module is provided, comprising:

[0047] The power module includes one of the above-mentioned reverse connection protection circuits for power input.

[0048] According to a third aspect of the present invention, an electrical appliance is provided, comprising:

[0049] The electrical equipment includes the power module described above.

[0050] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0051] This application uses a voltage detection module to detect the voltage of the power supply, an identification module to identify the positive and negative terminals of the power supply based on the voltage, and a switching module to control the opening and closing of components within an electronic switch based on the identification results. By controlling the opening and closing of each component within the electronic switch, the direction of current flow is always from the positive terminal of the load to the negative terminal, ensuring that the positive and negative terminals of the load remain consistent. In other words, regardless of whether the positive and negative terminals of the power supply are reversed, the positive terminal of the load always corresponds to the positive terminal of the power supply, and the negative terminal of the load always corresponds to the negative terminal of the power supply. With this application, when the power supply is reversed, no manual operation is required to change the positive and negative terminals of the power supply, and the load can still operate normally even when the power supply is reversed.

[0052] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0053] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0054] Figure 1 This is an overall schematic diagram of a power input reverse connection protection circuit according to an exemplary embodiment;

[0055] Figure 2 This is a circuit connection diagram of a power input reverse connection protection circuit according to another exemplary embodiment;

[0056] Figure 3 This is a schematic diagram of voltage detection relationship according to another exemplary embodiment;

[0057] Figure 4 This is a schematic diagram illustrating a current detection relationship according to an exemplary embodiment;

[0058] In the attached diagram: 1-Electronic switch, 2-Voltage detection module, 3-Identification module, 4-Switching module. Detailed Implementation

[0059] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention as detailed in the appended claims.

[0060] Example 1

[0061] Figure 1 This is an overall schematic diagram of a power input reverse connection protection circuit according to an exemplary embodiment, such as... Figure 1 As shown, it includes:

[0062] Electronic switch 1 is located between the power interface and the load interface;

[0063] Voltage detection module 2, identification module 3, and switching module 4 are connected in sequence;

[0064] The input terminal of the voltage detection module 2 is connected to the power interface, and the output terminal of the switching module 4 is connected to the control terminal of the electronic switch 1.

[0065] The voltage detection module 2 is used to detect the voltage value of the external power supply connected to the power interface; the identification module 3 is used to determine the positive and negative terminals of the external power supply based on the voltage value; the switching module 4 is used to control the on / off state of the electronic switch 1 based on the positive and negative terminals, so that when the external power supply is blindly plugged into the power interface, the power direction of the external power supply flowing to the positive and negative terminals of the load remains unchanged.

[0066] Understandably, in this embodiment, the voltage detection module 2 detects the voltage of the power supply, the identification module 3 identifies the positive and negative terminals of the power supply based on the voltage, and the switching module 4 controls the opening and closing of the components in the electronic switch 1 based on the identification result. By opening and closing each component in the electronic switch 1, the direction of current flow is always from the positive terminal of the load to the negative terminal, so that the positive and negative terminals of the load are always consistent. That is to say, regardless of whether the positive and negative terminals of the power supply are reversed, the positive terminal of the load always corresponds to the positive terminal of the power supply, and the negative terminal of the load always corresponds to the negative terminal of the power supply. With this application, when the power supply is reversed, there is no need to manually change the positive and negative terminals of the power supply, and the load can still operate normally even when the power supply is reversed.

[0067] Preferably, the electronic switch 1 includes:

[0068] Four unidirectional conducting switching elements, which are paired up to form a first conducting branch and a second conducting branch respectively.

[0069] in,

[0070] The first and second conducting branches are connected in parallel between the positive and negative terminals of the power supply and the load, and are respectively connected to the switching module 4;

[0071] It is understandable that when the first terminal P1 of the power supply is positive and the second terminal P2 is negative, the power supply supplies power to the load through the first conducting branch. When the first terminal P1 of the power supply is negative and the second terminal P2 is positive, the power supply supplies power to the load through the second conducting branch. Through the unidirectional conducting switching elements in the first and second conducting branches, the direction of current flow in the load remains unchanged regardless of how the positive and negative terminals of the first terminal P1 and the second terminal P2 of the power supply change.

[0072] Preferably, the first conducting branch includes:

[0073] The first switching element Q4 has its first pin connected to the switching module 4, its second pin connected to the first terminal P1 of the power supply, and its third pin connected to the positive terminal of the load.

[0074] The second switching element Q3 has its first pin connected to the switching module 4, its second pin connected to the negative terminal of the load, and its third pin connected to the second terminal P2 of the power supply.

[0075] Wherein, when the first switching element Q4 and the second switching element Q3 are both IGBT modules, the first pin is the gate, the second pin is the collector, and the third pin is the emitter;

[0076] When the first terminal P1 of the power supply is positive, the second terminal P2 of the power supply is negative; when the first terminal P1 of the power supply is negative, the second terminal P2 of the power supply is positive.

[0077] Understandably, as shown in the attached document Figure 2 As shown, when the first terminal P1 of the power supply is positive and the second terminal P2 is negative, the current flows out from P1 of the power supply, through the second pin of Q4, through the third pin of Q4, through the positive terminal of the load, through the negative terminal of the load, through the second pin of Q3, and back to P2 of the power supply, completing the cycle. The first pins of both Q3 and Q4 are connected to the switching module 4, which controls the opening and closing of Q3 and Q4.

[0078] It is worth emphasizing that Q4 and Q3 can be IGBT modules, or unidirectional electronic switching devices such as relays and MOSFETs.

[0079] Preferably, the second conducting branch includes:

[0080] The third switching element Q2 has its first pin connected to the switching module 4, its second pin connected to the negative terminal of the load, and its third pin connected to the first terminal P1 of the power supply.

[0081] The fourth switching element Q1 has its first pin connected to the switching module 4, its second pin connected to the second terminal P2 of the power supply, and its third pin connected to the positive terminal of the load.

[0082] Wherein, when the first switching element Q2 and the second switching element Q1 are both IGBT modules, the first pin is the gate, the second pin is the collector, and the third pin is the emitter;

[0083] Understandably, as shown in the attached document Figure 2 As shown, when the first terminal P1 of the power supply is negative and the second terminal P2 is positive, the current flows out from P2 of the power supply, through the second pin of Q1, through the third pin of Q1, through the positive terminal of the load, through the negative terminal of the load, through the second pin of Q2, and back to P1 of the power supply from the third pin of Q2, completing the cycle. The first pins of both Q1 and Q2 are connected to the switching module 4, which controls the opening and closing of Q1 and Q2.

[0084] Preferably, the voltage detection module 2 includes:

[0085] The first operational amplifier U1 has its non-inverting input terminal connected to the second terminal P2 of the power supply, its inverting input terminal connected to the first terminal P1 of the power supply, and its output terminal connected to the identification module 3.

[0086] Understandably, as shown in the attached documentFigure 2 As shown, the voltage between the first terminal P1 and the second terminal P2 of the power supply is detected by the first operational amplifier U1, and the detected voltage value is amplified by positive or negative amplification and then output as a voltage value. The voltage value is sent to the identification module 3. The identification module 3 determines the positive and negative terminals of the first terminal P1 and the second terminal P2 of the power supply based on the magnitude of the voltage value output by the first operational amplifier U1. Among them, resistors R1, R2, R3 and R4 are matching resistors.

[0087] Preferably, the identification module 3 includes:

[0088] The first comparator U2 has its input terminal connected to the output terminal of the first operational amplifier U1, and its output terminal connected to the switching module.

[0089] The first comparator U2 is used to compare the output voltage of the first operational amplifier U1 with the first reference voltage V1 of the first operational amplifier U1, and output a high-level signal or a low-level signal according to the comparison result.

[0090] Understandably, as shown in the attached document Figure 2 As shown, the identification module 3 compares the voltage value output by the first operational amplifier U1 with the first reference voltage V1. The first reference voltage V1 is half of the supply voltage of the first operational amplifier U1. The principle of the comparison is as follows:

[0091] When P1 is positive and P2 is negative, the output voltage U of the first operational amplifier U1 is less than the first reference voltage V1; when P2 is positive and P1 is negative, the output voltage U of the first operational amplifier U1 is greater than the first reference voltage V1.

[0092] When P2 is positive and P1 is negative:

[0093]

[0094] When P1 is positive and P2 is negative:

[0095]

[0096] In the formula, U VO U1 is the output voltage, U V This represents the input voltage of U1;

[0097] In other words, when P1 is positive and P2 is negative, the first operational amplifier U1 is equivalent to reverse amplification, so the output voltage U of the first operational amplifier U1 is less than the first reference voltage V1. When P2 is positive and P1 is negative, the first operational amplifier U1 is equivalent to forward amplification, so the output voltage U of the first operational amplifier U1 is greater than the first reference voltage V1. The comparator is a circuit that compares an analog voltage signal with a reference voltage. The two inputs of the comparator are analog signals, and the output is a binary signal 0 or 1. That is, the first comparator U2 can output a high-level signal or a low-level signal according to the positive and negative terminals of the power supply P1 and P2.

[0098] Preferably, the switching module 4 includes:

[0099] Tri-state gate U6, tri-state gate U7, inverter U5, first driving circuit and second driving circuit;

[0100] The output of the first comparator U2 is connected to the input of the tri-state gate U6 and the inverter U5 respectively. The output of the tri-state gate U6 is connected to the second driving circuit, which is used to control the opening and closing of the second conducting branch.

[0101] The output terminal of the inverter U5 is connected to the input terminal of the tri-state gate U7, and the output terminal of the tri-state gate U7 is connected to the first driving circuit. The first driving circuit is used to control the opening and closing of the first conducting branch.

[0102] Understandably, as shown in the attached document Figure 2 As shown, the high-level or low-level signal output by the first comparator U2 directly enters the input terminals of the tri-state gate U6 and the inverter U5. After the signal is inverted by the inverter U5, it enters the tri-state gate U7. That is to say, the signal entering the tri-state gates U7 and U6 must be one high level and one low level. The logic signals output by the tri-state gates U6 and U7 control the second driving circuit and the first driving circuit respectively. Since the signals input to the tri-state gates U6 and U7 are opposite, the second driving circuit performs an on operation and the first driving circuit performs an off operation, realizing the interlocking of the first conduction branch and the second conduction branch. When Q1, Q2, Q3 and Q4 are IGBT modules, the second driving circuit is connected to the gates of Q1 and Q2 respectively to control the on or off of Q1 and Q2 simultaneously. The first driving circuit is connected to the gates of Q3 and Q4 respectively to control the on or off of Q3 and Q4 simultaneously.

[0103] Preferably, it further includes:

[0104] Overvoltage detection module,

[0105] The overvoltage detection module includes comparator U3 and comparator U4;

[0106] The negative pin of comparator U3 and the positive pin of comparator U4 are respectively connected to the output terminal of the first operational amplifier U1. The positive pin of comparator U3 is input to the third reference voltage V3, and the negative pin of comparator U4 is input to the second reference voltage V2.

[0107] The comparator U3 and comparator U4 together form a threshold comparator;

[0108] It is understood that comparator U3 is used to compare the output voltage of operational amplifier U1 with the third reference voltage V3, and outputs a high-level signal or a low-level signal according to the comparison result; comparator U4 is used to compare the output voltage of operational amplifier U1 with the second reference voltage V2, and outputs a high-level signal or a low-level signal according to the comparison result; the third reference voltage V3 is the maximum input voltage value where P2 is positive and P1 is negative; the second reference voltage V2 is the maximum input voltage value where P1 is positive and P2 is negative; as shown in the appendix. Figure 3 The figure shows the relationship between the first reference voltage V1, the second reference voltage V2, and the third reference voltage V3, where V3>V1>V2;

[0109] Preferably, it further includes:

[0110] Overcurrent detection module,

[0111] The overcurrent detection module includes a second operational amplifier U11, a comparator U9, and a comparator U10;

[0112] The non-inverting input terminal of the operational amplifier U11 is connected to the first terminal P1 of the power supply, and the inverting input terminal of the operational amplifier U11 is connected to the second terminal P2 of the power supply.

[0113] The output terminal of the operational amplifier U11 is connected to the negative terminal of comparator U9 and the positive terminal of comparator U10, respectively.

[0114] The positive pin of comparator U9 receives the third sampling current V6, and the negative pin of comparator U10 receives the second sampling current V5.

[0115] It is understandable that, utilizing the internal resistances of Q1 and Q3, when current flows through them, a voltage is generated across Q1 and Q3. When P1 is positive and P2 is negative, current flows out of Q3, and the operational amplifier's output current is greater than the first sampling current V4; when P2 is positive and P1 is negative, current flows into Q1, and the operational amplifier's output current is less than the first sampling current V4. R5, R6, R7, and R8 are matching resistors, and their operational relationship is as follows:

[0116] When P1 is positive and P2 is negative, the current flows out of Q3:

[0117]

[0118] When P2 is positive and P1 is negative, the current flows in from Q1:

[0119]

[0120] The comparator U9 compares the output current of operational amplifier U11 with the third sampling current V6, and outputs a high-level signal or a low-level signal based on the comparison result; the comparator U10 compares the output current of operational amplifier U11 with the second sampling current V5, and outputs a high-level signal or a low-level signal based on the comparison result; the second sampling current V5 is the maximum current when P2 is positive and P1 is negative; the third sampling current V6 is the maximum current when P2 is negative and P1 is positive, as shown in the appendix. Figure 4 The figure shows the relationship between the first sampling current V4, the second sampling current V5, and the third sampling current V6, where V6>V4>V5.

[0121] Preferably, it further includes:

[0122] Protection module: includes AND gate U8;

[0123] The input terminals of AND gate U8 are respectively connected to the output terminals of comparator U3, comparator U4, comparator U9 and comparator U10;

[0124] The output of AND gate U8 is connected to the input of tri-state gate U6 and tri-state gate U7, respectively;

[0125] It is understandable that when the input current is not between the preset current sampling value V5 and the current sampling value V6, or when the input voltage is not between the preset reference voltage V2 and the reference voltage V3, the AND gate U8 outputs a logic high level, and the enable levels of the tri-state gate U6 and the tri-state gate U are high, resulting in a high output configuration. The first driving circuit and the second driving circuit respectively control the first conducting branch and the second conducting branch to disconnect. That is, in the case of overvoltage or overcurrent, the first driving circuit and the second driving circuit will simultaneously disconnect the first conducting branch and the second conducting branch, thus disconnecting the current from the load and preventing the load from being burned out in the case of overvoltage or overcurrent.

[0126] Example 2

[0127] According to a second aspect of the present invention, a power supply module is provided, comprising:

[0128] The power module includes one of the above-mentioned reverse connection protection circuits for power input.

[0129] It is understandable that any module that requires power wiring can be a power module, and can use the power input reverse connection protection circuit described in this application to avoid the problem that the load cannot operate normally when the positive and negative terminals of the power supply are reversed.

[0130] Example 3

[0131] According to a third aspect of the present invention, an electrical appliance is provided, comprising:

[0132] The electrical equipment includes the aforementioned power module;

[0133] It is understood that the electrical equipment mentioned may be electronic products such as air conditioning units and humidifiers.

[0134] It is understood that the same or similar parts in the above embodiments can be referred to each other, and the contents not described in detail in some embodiments can be referred to the same or similar contents in other embodiments.

[0135] It should be noted that in the description of this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means at least two.

[0136] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

[0137] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0138] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0139] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0140] The storage media mentioned above can be read-only memory, disk, or optical disk, etc.

[0141] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0142] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A power input reverse connection protection circuit, characterized in that, include: An electronic switch is located between the power interface and the load interface; The voltage detection module, identification module, and switching module are connected in sequence. The switching module includes: Tri-state gate U6, tri-state gate U7, inverter U5, first driving circuit and second driving circuit; The output of the first comparator U2 is connected to the input of the tri-state gate U6 and the inverter U5 respectively. The output of the tri-state gate U6 is connected to the second driving circuit, which is used to control the opening and closing of the second conducting branch. The output terminal of the inverter U5 is connected to the input terminal of the tri-state gate U7, and the output terminal of the tri-state gate U7 is connected to the first driving circuit. The first driving circuit is used to control the opening and closing of the first conducting branch. The input terminal of the voltage detection module is connected to the power interface, and the output terminal of the switching module is connected to the control terminal of the electronic switch. The voltage detection module is used to detect the voltage value of the external power supply connected to the power interface, and the identification module is used to determine the positive and negative terminals of the external power supply based on the voltage value. The switching module is used to control the on / off state of the electronic switch based on the positive and negative terminals, so that when the external power supply is blindly plugged into the power interface, the power direction of the external power supply flowing to the positive and negative terminals of the load remains unchanged.

2. The circuit according to claim 1, characterized in that, The electronic switch includes: Four unidirectional conducting switching elements, which are paired up to form a first conducting branch and a second conducting branch respectively. in, The first and second conducting branches are connected in parallel between the positive and negative terminals of the power supply and the load, and are respectively connected to the switching module.

3. The circuit according to claim 2, characterized in that, The first conducting branch includes: The first switching element Q4 has its first pin connected to the switching module, its second pin connected to the first terminal P1 of the power supply, and its third pin connected to the positive terminal of the load. The second switching element Q3 has its first pin connected to the switching module, its second pin connected to the negative terminal of the load, and its third pin connected to the second terminal P2 of the power supply. Wherein, when the first switching element Q4 and the second switching element Q3 are both IGBT modules, the first pin is the gate, the second pin is the collector, and the third pin is the emitter; When the first terminal P1 of the power supply is positive, the second terminal P2 of the power supply is negative, and when the first terminal P1 of the power supply is negative, the second terminal P2 of the power supply is positive.

4. The circuit according to claim 3, characterized in that, The second conducting branch includes: The third switching element Q2 has its first pin connected to the switching module, its second pin connected to the negative terminal of the load, and its third pin connected to the first terminal P1 of the power supply. The fourth switching element Q1 has its first pin connected to the switching module, its second pin connected to the second terminal P2 of the power supply, and its third pin connected to the positive terminal of the load. When both the first switching element Q2 and the second switching element Q1 are IGBT modules, the first pin is the gate, the second pin is the collector, and the third pin is the emitter.

5. The circuit according to claim 4, characterized in that, The voltage detection module includes: The first operational amplifier U1 has its non-inverting input connected to the second terminal P2 of the power supply, its inverting input connected to the first terminal P1 of the power supply, and its output connected to the identification module.

6. The circuit according to claim 5, characterized in that, The identification module includes: The first comparator U2 has its input terminal connected to the output terminal of the first operational amplifier U1, and its output terminal connected to the switching module. The first comparator U2 is used to compare the output voltage of the first operational amplifier U1 with the first reference voltage V1 of the first operational amplifier U1, and output a high-level signal or a low-level signal according to the comparison result.

7. The circuit according to claim 6, characterized in that, Also includes: Overvoltage detection module, The overvoltage detection module includes comparator U3 and comparator U4; The negative pin of comparator U3 and the positive pin of comparator U4 are respectively connected to the output terminal of the first operational amplifier U1. The positive pin of comparator U3 is input to the third reference voltage V3, and the negative pin of comparator U4 is input to the second reference voltage V2. The comparator U3 and comparator U4 together form a threshold comparator.

8. The circuit according to claim 7, characterized in that, Also includes: Overcurrent detection module, The overcurrent detection module includes a second operational amplifier U11, a comparator U9, and a comparator U10; The non-inverting input terminal of the operational amplifier U11 is connected to the first terminal P1 of the power supply, and the inverting input terminal of the operational amplifier U11 is connected to the second terminal P2 of the power supply. The output terminal of the operational amplifier U11 is connected to the negative terminal of comparator U9 and the positive terminal of comparator U10, respectively. The positive pin of comparator U9 receives the third sampling current V6, and the negative pin of comparator U10 receives the second sampling current V5.

9. The circuit according to claim 8, characterized in that, Also includes: Protection module: includes NAND gate U8; The input terminals of the NAND gate U8 are respectively connected to the output terminals of comparators U3, U4, U9 and U10; The output of the NAND gate U8 is connected to the inputs of the tri-state gate U6 and the tri-state gate U7, respectively.

10. A power supply module, characterized in that, include: The power module includes a power input reverse connection protection circuit as described in any one of claims 1-9.

11. An electrical appliance, characterized in that, include: The electrical equipment includes the power module as described in claim 10.

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