Direct-current overcurrent protection circuit, electronic circuit breaker and direct-current power supply system

Abstract

The utility model relates to a direct current overcurrent protection circuit, an electronic circuit breaker and a direct current power supply system, and the circuit comprises a current sampling module which is used for connecting a direct current power supply and carrying out the current sampling and outputting a voltage signal; the input end of the power supply switch module is connected with the current sampling module, and the output end of the power supply switch module is used for being connected with direct current equipment; the control module is respectively connected with the control end of the power supply switch module and the current sampling module; the control module receives the voltage signal and judges whether overcurrent occurs in the direct current equipment according to the voltage signal so as to control the on-off state of the power supply switch module. According to the invention, over-current protection of the direct-current equipment can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic circuit, in particular to a direct current overcurrent protection circuit, an electronic circuit breaker and a direct current power supply system. BACKGROUND

[0002] When a plurality of direct current devices are powered by a high-power switching power supply, all the direct current devices share the switching power supply. However, the switching power supply can only perform overcurrent protection on the total current output by the power supply. If overcurrent occurs in a single direct current device in a branch, the situation in the branch cannot be monitored, and overcurrent in the direct current device in the branch will affect the normal power supply of other direct current devices. CONTENT OF THE INVENTION

[0003] Therefore, it is necessary to provide a direct current overcurrent protection circuit, an electronic circuit breaker and a direct current power supply system capable of performing overcurrent protection on a single direct current device.

[0004] In a first aspect, in one embodiment, the present application provides a direct current overcurrent protection circuit, comprising:

[0005] a current sampling module, configured to be connected to a direct current power supply, the current sampling module performing current sampling and outputting a voltage signal;

[0006] a power supply switch module, an input end of the power supply switch module being connected to the current sampling module, and an output end of the power supply switch module being configured to be connected to a direct current device;

[0007] a control module, the control module being connected to a control end of the power supply switch module and the current sampling module respectively; the control module receiving the voltage signal, judging whether overcurrent occurs in the direct current device according to the voltage signal, and controlling the on-off state of the power supply switch module.

[0008] In one embodiment, the current sampling module comprises a sampling resistor, a current sensor and a voltage dividing unit.

[0009] One end of the sampling resistor is configured to be connected to the direct current power supply, and the other end of the sampling resistor is connected to the input end of the power supply switch module.

[0010] A first end of the current sensor is configured to be connected to the direct current power supply, a second end of the current sensor is connected to the input end of the power supply switch module, and a third end of the current sensor is connected to the control module through the voltage dividing unit.

[0011] In one embodiment, the voltage dividing unit comprises a first voltage dividing resistor and a second voltage dividing resistor, and the current sampling module further comprises a first capacitor.

[0012] One end of the first voltage dividing resistor is connected to the third end of the current sensor, and the other end of the first voltage dividing resistor R21 is connected to the control module; one end of the second voltage dividing resistor is connected between the other end of the first voltage dividing resistor R21 and the control module, and the other end of the second voltage dividing resistor is used for grounding;

[0013] One end of the first capacitor is connected between the other end of the first voltage dividing resistor and one end of the second voltage dividing resistor, and the other end of the first capacitor is used for grounding.

[0014] In one embodiment, the current sensor comprises a current sense amplifier.

[0015] In one embodiment, the power supply switching module comprises a first resistor, a first switching unit and a second switching unit;

[0016] One end of the first resistor is connected to the current sampling module, and the other end of the first resistor is connected to one end of the first switching unit;

[0017] The control end of the first switching unit is connected to the control module, and the other end of the first switching unit is used for connecting the DC device and grounding;

[0018] The control end of the second switching unit is connected between the other end of the first resistor and one end of the first switching unit, one end of the second switching unit is connected to the current sampling module, and the other end of the second switching unit is used for connecting the DC device.

[0019] In one embodiment, the DC overcurrent protection circuit further comprises a power supply module connected between the DC power supply and the control module; wherein:

[0020] The power supply module comprises a second resistor, a third resistor, a fourth resistor, a second capacitor, a polarity capacitor, a voltage stabilizing diode and a diode; the positive electrode of the diode is used for connecting the DC power supply, the negative electrode of the diode is respectively connected to the positive electrode of the polarity capacitor and one end of the second resistor, the other end of the second resistor is respectively connected to the control module, one end of the third resistor and the cathode of the voltage stabilizing diode;

[0021] The other end of the third resistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is used for grounding; the reference end of the voltage stabilizing diode is connected between the other end of the third resistor and one end of the fourth resistor;

[0022] The anode of the voltage stabilizing diode and the negative electrode of the polarity capacitor are used for grounding; one end of the second capacitor is connected between the other end of the second resistor and the control module, and the other end of the second capacitor is used for grounding.

[0023] In one embodiment, the control module comprises an MCU;

[0024] The first pin of the MCU is electrically connected to the control end of the power supply switch module, and the second pin of the MCU is electrically connected to the current sampling module.

[0025] In one of the embodiments, the circuit further comprises a state indication module connected to the control module; the state indication module comprises a seventh resistor and a light emitting diode.

[0026] One end of the seventh resistor is connected to the control module, the other end of the seventh resistor is connected to one end of the light emitting diode, and the other end of the light emitting diode is grounded.

[0027] In the second aspect, in one of the embodiments, the present application further provides an electronic circuit breaker, comprising the DC overcurrent protection circuit according to any one of the first aspect.

[0028] In the third aspect, in one of the embodiments, the present application further provides a DC power supply system, comprising a DC power supply, a plurality of electronic circuit breakers according to the second aspect, and a plurality of DC devices.

[0029] The DC power supply is connected to each electronic circuit breaker, and each electronic circuit breaker is connected to each DC device one by one.

[0030] The DC overcurrent protection circuit, the electronic circuit breaker and the DC power supply system can sample current and output voltage signals through the current sampling module connected to the DC power supply, and then the control module can determine whether overcurrent occurs in the DC device according to the received voltage signals, so as to control the on-off state of the connected power supply switch module, thereby avoiding affecting other DC devices in the case of overcurrent of part of the DC devices, and completing overcurrent protection of the DC devices. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0032] Figure 1 It is a structure block diagram of the DC overcurrent protection circuit in one embodiment.

[0033] Figure 2 It is a structure schematic diagram of the current sampling module in one embodiment.

[0034] Figure 3 It is a circuit structure schematic diagram of the voltage dividing unit in one embodiment.

[0035] Figure 4 It is a circuit schematic diagram of the power supply switch module in one embodiment.

[0036] Figure 5 a circuit structure block diagram of a power module in an embodiment;

[0037] Figure 6 a circuit structure diagram of a power module in an embodiment;

[0038] Figure 7 a circuit structure diagram of a control module in an embodiment;

[0039] Figure 8 a circuit structure block diagram of a status indication module in an embodiment;

[0040] Figure 9 a circuit structure diagram of a DC over-current protection circuit in an embodiment;

[0041] Figure 10 a structure block diagram of a DC power supply system in an embodiment. DETAILED DESCRIPTION

[0042] In order to facilitate the understanding of the present application, a more complete description of the present application will be provided below with reference to the relevant drawings. The drawings show embodiments of the present application. However, the present application can be implemented in many different forms, and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the specification of the present application is only for the purpose of describing specific embodiments of the present application, and is not intended to limit the present application.

[0044] It can be understood that the terms "first", "second" and the like used in the present application can be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element. For example, without departing from the scope of the present application, the first resistor can be referred to as the second resistor, and similarly, the second resistor can be referred to as the first resistor. The first resistor and the second resistor are both resistors, but they are not the same resistor.

[0045] It can be understood that "connection" in the following embodiments, if the circuits, modules, units and the like connected to each other have the transmission of electrical signals or data, should be understood as "electrical connection", "communication connection" and the like.

[0046] It can be understood that "at least one" means one or more, and "multiple" means two or more. "At least part of the element" means part or all of the element.

[0047] As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. It should also be understood that the term "comprising" or "including" or "having" or the like, as used herein, is intended to mean the presence of stated features, integers, steps, components, parts, or combinations thereof, but does not preclude the presence or addition of one or more other features, integers, steps, components, parts, or combinations thereof. In addition, the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0048] In the industrial industry, a high-power switching power supply is generally used to supply power to multiple DC devices, at this time each DC device is sharing the high-power switching power supply. However, this switching power supply can only provide overcurrent protection for the total current of the system, and if an individual DC device has an overcurrent, it may affect other DC devices. In addition, the existing DC overcurrent protection method also has the problems of complex circuit components, high cost, and poor visibility. Based on the above problems, the present application provides a DC overcurrent protection circuit, an electronic circuit breaker and a DC power supply system.

[0049] In one embodiment, as shown in Figure 1 The present application provides a DC overcurrent protection circuit 10, comprising:

[0050] A current sampling module 12 is connected to a DC power supply 30, and the current sampling module 12 samples the current and outputs a voltage signal;

[0051] A power supply switch module 14 is connected to the current sampling module 12 at the input end, and the output end of the power supply switch module 14 is used to connect the DC device 20;

[0052] A control module 16 is connected to the control end of the power supply switch module 14 and the current sampling module 12, respectively. The control module 16 receives the voltage signal, judges whether the DC device 20 has an overcurrent according to the voltage signal, and controls the on-off state of the power supply switch module 14.

[0053] Specifically, the current sampling module 12 can sample the power supply current output by the DC power supply 30, for example, the current sampling module 12 samples the power supply current flowing through to obtain a sampling current, and outputs a voltage signal corresponding to the sampling current, which can simplify the sampling circuit.

[0054] Exemplarily, the current sampling module 12 can sample and detect the current flowing through the current sampling module 12, obtain a sampling current, and convert the sampling current into a voltage signal in a certain linear proportion and output to the control module 16. For example, the current sampling module 12 can convert the sampling current of 0A to 10A into a voltage signal of 0V to 2V in a linear proportion, and output the voltage signal to the control module 16. It can be understood that the linear proportion is not limited to the implementation manner mentioned in the above embodiment, as long as it can establish the corresponding relationship between the sampling current and the voltage output by the current sampling module 12, and the specific setting manner of the linear proportion is not limited in the present application.

[0055] The control module 16 can determine whether the overcurrent occurs in the direct current device 20 according to the voltage signal output by the current sampling module 12, so as to control the on-off state of the power supply switch module 14. It can be understood that when the control module 16 controls the power supply switch module 14 to be turned on through the control end of the power supply switch module 14, the power supply current output by the direct current power supply 30 can supply direct current for the direct current device 20; when the control module 16 controls the power supply switch module 14 to be turned off through the control end of the power supply switch module 14, the current flowing through the power supply switch module 14 of the direct current power supply 30 is cut off, thereby preventing the direct current power supply 30 from continuing to supply power for the direct current device 20.

[0056] Exemplarily, the control module 16 can obtain the detection current by inversely converting the voltage signal output by the current sampling module 12. When the detection current exceeds the preset overcurrent threshold of the control module 16, it can be determined that the overcurrent phenomenon occurs in the circuit, thereby realizing the overcurrent protection without changing the hardware, which is beneficial to reduce the cost. It should be understood that the above-mentioned preset overcurrent threshold can be preset in the control module 16 according to the specific application requirements of the device, the specifications of the circuit elements and other factors, and the setting manner of the preset overcurrent threshold is not limited in the present application.

[0057] Furthermore, the DC power supply 30 outputs a supply current to the current sampling module 12. The current sampling module 12 samples and detects the supply current flowing through it and outputs a voltage signal corresponding to the detected current to the control module 16. After receiving the voltage signal output by the current sampling module 12, the control module 16 converts the voltage signal into a corresponding sampled current value and compares it with a preset overcurrent threshold stored in the control module 16. If the sampled current value is less than or equal to the preset overcurrent threshold, the control module 16 determines that the circuit is operating normally and controls the power supply switch module 14 to turn on through the control terminal of the power supply switch module 14, so that the DC power supply 30 supplies power to the DC device 20. If the sampled current value is greater than the preset overcurrent threshold, the control module 16 determines that an overcurrent has occurred in the circuit and controls the power supply switch module 14 to turn off through the control terminal of the power supply switch module 14, so that the DC power supply 30 stops supplying power to the corresponding DC device 20 in the event of an overcurrent in the circuit.

[0058] Optionally, the DC overcurrent protection circuit 10 may further include a fuse module, and the current sampling module 12 is connected to the DC power supply 30 through the fuse module. Exemplarily, the fuse module may include a fuse. It is understood that when the DC power supply inputs a large instantaneous current to the current sampling module, the metal wire inside the fuse will melt due to overheating, thereby cutting off the connection between the circuit and the DC power supply, further preventing damage to circuit components due to overload or short circuit, and avoiding accidents such as fires.

[0059] Optionally, the DC overcurrent protection circuit 10 may further include a power supply connection module, through which the current sampling module 12 is connected to the DC power supply 30. Exemplarily, the power supply connection module may include a first connector; wherein the first connector further includes two grounding terminals for grounding, and a power supply terminal for receiving the power supply current input from the DC power supply 30.

[0060] Through the above methods, this application can achieve overcurrent protection for individual DC devices, preventing the overcurrent of individual DC devices from affecting the normal operation of other DC devices.

[0061] In one embodiment, such as Figure 2 As shown, the current sampling module 12 includes a sampling resistor 122, a current sensor 124, and a voltage divider unit 126;

[0062] One end of the sampling resistor 122 is used to connect to the DC power supply 30, and the other end of the sampling resistor 122 is connected to the input terminal of the power supply switch module 18.

[0063] The first end of the current sensor 124 is connected to the DC power supply 30, the second end of the current sensor 124 is connected to the input end of the power supply switch module 18, and the third end of the current sensor 124 is connected to the control module 16 through the voltage dividing unit 126.

[0064] The current sensor 124 can linearly change the voltage generated by the current between the sampling resistor 122, and the voltage dividing unit 126 can divide the voltage to be collected by the control module 16. For example, the linear change can be a proportional amplification, for example, the sampling current of 0A to 10A can be converted to a voltage signal of 0V to 2V based on a preset linear ratio. It can be understood that the setting mode of the linear change can also include other modes, and the application does not specifically limit the setting mode of the linear change.

[0065] Specifically, the power supply current input by the DC power supply 30 flows through the sampling resistor 122, the current sensor 124 linearly changes the voltage generated by the current between the sampling resistor 122, and then outputs from the third end of the current sensor 124 to the voltage dividing unit 126 for voltage division. The voltage signal after voltage division is output to the control module 16.

[0066] In one embodiment, as shown in Figure 3 The voltage dividing unit 126 includes a first voltage dividing resistor R21 and a second voltage dividing resistor R22, and the current sampling module further includes a first capacitor C1.

[0067] One end of the first voltage dividing resistor R21 is connected to the third end of the current sensor, the other end of the first voltage dividing resistor R21 is connected to the control module, one end of the second voltage dividing resistor R22 is connected between the other end of the first voltage dividing resistor R21 and the control module, and the other end of the second voltage dividing resistor R22 is connected to the ground.

[0068] One end of the first capacitor C1 is connected between the other end of the first voltage dividing resistor R21 and one end of the second voltage dividing resistor R22, and the other end of the first capacitor C1 is connected to the ground.

[0069] The voltage dividing unit can divide the voltage signal output by the current sensor for signal collection by the control module.

[0070] Specifically, the voltage signal output by the current sensor is divided by the first voltage dividing resistor and the second voltage dividing resistor of the voltage dividing unit, and then transmitted to the control module, so that the voltage signal output by the current sensor can be prevented from being too large to damage the control module.

[0071] In one embodiment, the current sensor includes a current sensing amplifier.

[0072] Among them, the current sensing amplifier can exemplarily adopt ZXCT1107SA three-terminal current sensing amplifier or other current sensing amplifiers of different models with the same function. It can be understood that the specific model of the current sensing amplifier is not limited to the implementation mode mentioned above, as long as it can realize the function of linearly changing the voltage generated by the current at both ends of the sampling resistor. The application does not specifically limit the type of current sensor.

[0073] Specifically, the current sensing amplifier can linearly change the voltage generated by the current at both ends of the sampling resistor to output a sampling voltage signal, and the sampling voltage signal is divided by the voltage dividing unit and output to the control module.

[0074] In one embodiment, the power supply switching module includes a first resistor, a first switching unit, and a second switching unit.

[0075] One end of the first resistor is connected to the current sampling module, and the other end of the first resistor is connected to one end of the first switching unit.

[0076] The control end of the first switching unit is connected to the control module, and the other end of the first switching unit is used to connect the DC device and is also used to ground.

[0077] The control end of the second switching unit is connected between the other end of the first resistor and one end of the first switching unit, one end of the second switching unit is connected to the current sampling module, and the other end of the second switching unit is used to connect the DC device.

[0078] Among them, the control ends of the first switching unit and the second switching unit can be used to control the conduction and cutoff of the first switching unit and the second switching unit based on the input control signal. It should be understood that when the first switching unit is in the conduction state, the current can flow from one end of the first switching unit to the other end of the first switching unit; when the second switching unit is in the conduction state, the current can flow from one end of the second switching unit to the other end of the second switching unit.

[0079] Specifically, when the circuit is running normally without overcurrent, the control module outputs a control signal to the control end of the first switching unit to control the first switching unit to conduct, and the first switching unit conducts to further control the second switching unit to conduct, so that the power supply current output from the current sampling module can pass through the second switching unit to supply power for the operation of the DC device. When the circuit has overcurrent, the control module outputs a control signal to the control end of the first switching unit to control the first switching unit to cut off, and the first switching unit cuts off to further control the second switching unit to cut off accordingly, so that the power supply current output from the current sampling module cannot be transmitted to the DC device through the second switching unit, thereby cutting off the power supply of the DC power supply to the DC device.

[0080] Optionally, in one exemplary embodiment, as shown in Figure 4 the first switch unit can be an NMOS tube, and the second switch unit can be a PMOS tube. The overcurrent protection current can further include a power transmission connection module, which can include a second connector, and the second connector can include a four-terminal connector, wherein two terminals of the second connector are connected to the other end of the first switch unit, and the other two terminals of the second connector are connected to the other end of the second switch unit. It can be understood that the second connector is also connected to the DC device to output the power supply current to power the DC device. Exemplarily, the control end of the NMOS tube is connected to the control module, and the control end of the PMOS is connected between the other end of the first resistor and the S pole of the NMOS tube. The D end of the NMOS tube is connected to the DC device through a four-terminal connector CON2, and is grounded at the same time; the D end of the PMOS tube is also connected to the DC device through the four-terminal connector CON2 to power the DC device when no overcurrent occurs in the circuit. It should be understood that the first switch unit and the second switch unit can also use other electronic components with the same switching function, and the specific component type is not limited in the present application.

[0081] Specifically, as shown in Figure 4 the first switch unit can be an NMOS tube Q1, and the second switch unit can be a PMOS tube Q2. When the circuit is normally running and no overcurrent occurs, the control module outputs a control signal to the control end of the NMOS tube Q1 to control the NMOS tube Q1 to be turned on, and the NMOS tube Q1 is turned on to further control the PMOS tube Q2 to be turned on, so that the power supply current output from the current sampling module can be transmitted to the connector CON2 through the PMOS tube Q2, and the connector CON2 inputs the power supply current to the DC device, thereby powering the operation of the DC device. When the circuit has an overcurrent, the control module outputs a control signal to the control end of the NMOS tube Q1 to control the NMOS tube Q1 to be turned off, and the NMOS tube Q1 is turned off to further control the PMOS tube Q2 to be turned off accordingly, so that the power supply current output from the current sampling module cannot be transmitted to the DC device through the PMOS tube Q2, thereby cutting off the power supply of the DC power supply to the DC device.

[0082] In one embodiment, as shown in Figure 5 and Figure 6 the DC overcurrent protection circuit further includes a power supply module 18 connected between the DC power supply 30 and the control module 16; wherein:

[0083] The power module 18 comprises a second resistor R2, a third resistor R3, a fourth resistor R4, a second capacitor C2, a polarity capacitor C10, a voltage stabilizing diode U3 and a diode D1; the positive pole of the diode D1 is used for connecting a direct current power supply 30, the negative pole of the diode D1 is respectively connected to the positive pole of the polarity capacitor C10 and one end of the second resistor R2, the other end of the second resistor R2 is respectively connected to the control module 16, one end of the third resistor R3 and the cathode of the voltage stabilizing diode U3;

[0084] The other end of the third resistor R3 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is used for grounding; the reference end of the voltage stabilizing diode U3 is connected between the other end of the third resistor R3 and one end of the fourth resistor R4;

[0085] The anode of the voltage stabilizing diode U3 and the negative pole of the polarity capacitor C10 are used for grounding; one end of the second capacitor C2 is connected between the other end of the second resistor R2 and the control module 16, and the other end of the second capacitor C2 is used for grounding.

[0086] The power module can convert part of the direct current high voltage current input by the direct current power supply into low voltage direct current power supply current to supply power to the control module.

[0087] Specifically, part of the direct current high voltage current of the direct current power supply input circuit can be converted into low voltage direct current power supply current capable of supplying power to the control module after being processed by the power module.

[0088] In one embodiment, the control module comprises an MCU.

[0089] The first pin of the MCU is electrically connected to the control end of the power switch module, and the second pin of the MCU is electrically connected to the current sampling module.

[0090] The MCU (Microcontroller Unit) is a microcontroller, which is a small computer system integrating a central processing unit, a memory, an input / output interface and a timer, etc. and is usually a single chip. The first pin of the MCU can output a corresponding control signal according to the overcurrent condition of the circuit obtained by analysis, and the control signal can be used to control the on-off of the power switch module. The second pin of the MCU can receive a voltage signal sampled and output by the current sampling module 12, and the MCU can determine the overcurrent condition of the current circuit based on the voltage signal. For example, when the circuit is in an overcurrent condition, the MCU outputs a control signal for turning off to control the power switch module 14 to be turned off; when the circuit is in a normal working condition (not overcurrent), the MCU outputs a control signal for turning on to control the power switch module 14 to be turned on.

[0091] Specifically, after the second pin of the MCU receives the voltage signal from the sampling output of the current sampling module, the MCU inversely converts the voltage signal into a detection current, and compares the detection current with a preset overcurrent threshold set in the MCU. If the detection current is less than or equal to the preset overcurrent threshold, it is determined that the circuit is in a normal working state, and the first pin of the MCU outputs a corresponding control signal to control the power supply switch module to be turned on, so that the DC power supply normally supplies power to the DC device. If the detection current is greater than the preset overcurrent threshold, it is determined that the circuit has an overcurrent, and the first pin of the MCU outputs a corresponding control signal to control the power supply switch module to be turned off, so that the DC power supply stops supplying power to the DC electronic device. The preset overcurrent threshold can be configured autonomously by the MCU, so that different specifications of overcurrent protection (such as 1A, 2A, 3A, etc.) can be realized without changing the hardware, which is conducive to the large-scale production of products and the reduction of production costs.

[0092] Further, as shown in Figure 7 the control module further includes a fifth resistor R5, a sixth resistor R6, a third capacitor C3, a fourth capacitor C4, and a fifth capacitor C5. Optionally, the MCU can further include a BOOT0 pin, an NRST pin, a VDDA pin, and a VDD pin.

[0093] Specifically, one end of the fifth resistor R5 is connected to ground, and the other end of the fifth resistor R5 is connected to the BOOT0 pin of the MCU. One end of the third capacitor C3 is connected to one end of the fifth resistor R5, and the other end of the third capacitor C3 is connected to the NRST pin of the MCU. One end of the fourth capacitor C4 is connected to one end of the fifth resistor R5, and the other end of the fourth capacitor C4 is connected to one end of the sixth resistor R6. The other end of the sixth resistor R6 is connected between the other end of the third capacitor C3 and the NRST pin of the MCU. One end of the fifth capacitor C5 is connected to one end of the fifth resistor R5, and the other end of the fifth capacitor C5 is connected between the control module and the VDDA pin of the MCU. The other end of the fifth capacitor C5 is also connected between the other end of the fourth capacitor C4 and one end of the sixth resistor R6. Further, the first pin of the MCU is connected to the control end of the power supply switch module 14, the second pin of the MCU is connected to the current sampling module 12, and the VDD pin and the VDDA of the MCU are connected to the power supply module 18 for power supply.

[0094] The fourth capacitor C4 and the fifth capacitor C5 can be used as a single-chip microcomputer bypass capacitor of the MCU, and the sixth resistor R6 and the third capacitor C3 can be used for MCU upper reset. The BOOT0 pin of the MCU can be used to determine whether the MCU is started from the internal flash memory or the external memory according to the high and low levels of the pin, and the high and low levels can be adjusted through the fifth resistor; the NRST pin of the MCU can be used to initialize and reset the MCU according to the high and low levels of the pin; the VDDA pin and the VDD pin of the MCU can be used to power the internal circuit of the MCU. It can be understood that the power module is connected to the VDDA pin and the VDD pin of the MCU to power the MCU.

[0095] Optionally, the MCU can adopt a GD32E230F8P6 microcontroller or a microcontroller with an ADC analog signal conversion to digital signal conversion function.

[0096] In one embodiment, please refer to Figure 8 The circuit further comprises a state indication module 19 connected to the control module 16; the state indication module 19 comprises a seventh resistor and a light-emitting diode.

[0097] One end of the seventh resistor is connected to the control module 16, and the other end of the seventh resistor is connected to one end of the light-emitting diode, and the other end of the light-emitting diode is grounded.

[0098] The light-emitting diode can perform a light-emitting operation when the control module 16 outputs a state indication signal. For example, the state indication signal can include a pulse current signal, and the light-emitting operation can include the light-emitting diode flashing at a set frequency, etc. It can be understood that the state indication signal can also include other forms of indication signals, and the form of the state indication signal is not limited in the present application.

[0099] Specifically, in response to an overcurrent occurring in the circuit, the control module 16 can output a state indication signal to the state indication module 19, and the state indication module 19 performs a light-emitting operation through the light-emitting diode after receiving the state indication signal, thereby realizing visual output of the state of the circuit.

[0100] In order to make the purpose, technical scheme and advantages of the present application more clear, in one exemplary embodiment, the present application provides an overcurrent protection circuit as Figure 9 shown in the figure.

[0101] Figure 9The shown overcurrent protection circuit includes a first connector CON1, a fuse F1, a sampling resistor R11, a current sensor U2, a first voltage dividing resistor R21, a second voltage dividing resistor R22, a first capacitor C1, a first resistor R1, a first switch unit (NMOS tube) Q1, a second switch unit (PMOS tube) Q2, a second connector CON2, a diode D1, a polarity capacitor C10, a second resistor R2, a third resistor R3, a fourth resistor R4, a voltage stabilizing diode U3, a second capacitor C2, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a light emitting diode LED, and an MCU U1. Exemplarily, the power module in the embodiment can convert part of the power supply current of the direct current power supply into a 3.3V power supply voltage and input the power supply voltage to the VDDA pin and the VDD pin of the MCU to supply power to the MCU. Optionally, the terminals for grounding of the first connector and the second connector can be short-circuited together. The connection mode between the above elements, the circuit operation mode, and the generated technical effects refer to the above embodiments, and will not be described here again.

[0102] In one embodiment, the application further provides an electronic circuit breaker comprising the direct current overcurrent protection circuit according to any one of the above embodiments.

[0103] Specifically, the direct current power supply can be connected with the direct current device through the electronic circuit breaker to supply power to the direct current device. Exemplarily, when overcurrent occurs in the connection circuit of the direct current power supply to the direct current device, the electronic circuit breaker can be disconnected accordingly to cut off the abnormal power supply of the direct current power supply to the direct current device.

[0104] In one embodiment, as Figure 10 shown, the application further provides a direct current power supply system comprising a direct current power supply 100, a plurality of electronic circuit breakers 102 according to any one of the above embodiments, and a plurality of direct current devices 104.

[0105] The direct current power supply 100 is connected with each electronic circuit breaker 102, and each electronic circuit breaker 102 is connected with each direct current device 104 in one-to-one correspondence.

[0106] Optionally, the direct current power supply can include a direct current switching power supply for switching control of the total power supply current output.

[0107] Specifically, one direct current power supply supplies power to a plurality of direct current devices through a plurality of branches, and an electronic circuit breaker can be arranged on each branch to disconnect the electronic circuit breaker of the branch when overcurrent occurs in the branch circuit to cut off the power supply of the direct current power supply to the direct current device of the branch.

[0108] In the description of the specification, the description of the terms "some embodiments", "other embodiments", etc. means that the particular feature, structure, material, or characteristic being described is included in at least one embodiment or example of the application. The illustrative descriptions in this specification are not necessarily to be construed as indicating that all embodiments or examples of the application include the described feature, structure, material or characteristic.

[0109] The technical features of the above-described embodiments can be combined in any manner, and for brevity, not all possible combinations of the technical features in the above-described embodiments are described, but it should be considered that any combination of the technical features is within the scope of the present application as long as the combination does not result in a contradiction.

[0110] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these are within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A direct current overcurrent protection circuit, characterized by, The direct current overcurrent protection circuit comprises: a current sampling module for connecting a direct current power supply, the current sampling module sampling current and outputting a voltage signal; a power supply switch module, an input end of the power supply switch module being connected to the current sampling module, and an output end of the power supply switch module being used for connecting a direct current device; a control module, the control module being connected to a control end of the power supply switch module and the current sampling module respectively; the control module receiving the voltage signal and judging whether the direct current device has overcurrent according to the voltage signal to control on-off state of the power supply switch module.

2. The circuit of claim 1, wherein, The current sampling module comprises a sampling resistor, a current sensor and a voltage dividing unit; one end of the sampling resistor is used for connecting the direct current power supply, and the other end of the sampling resistor is connected to the input end of the power supply switch module; a first end of the current sensor is used for connecting the direct current power supply, a second end of the current sensor is connected to the input end of the power supply switch module, and a third end of the current sensor is connected to the control module through the voltage dividing unit.

3. The circuit of claim 2, wherein, The voltage dividing unit comprises a first voltage dividing resistor and a second voltage dividing resistor; and the current sampling module further comprises a first capacitor; one end of the first voltage dividing resistor is connected to the third end of the current sensor, the other end of the first voltage dividing resistor is connected to the control module; one end of the second voltage dividing resistor is connected between the other end of the first voltage dividing resistor and the control module, and the other end of the second voltage dividing resistor is used for grounding; one end of the first capacitor is connected between the other end of the first voltage dividing resistor and one end of the second voltage dividing resistor, and the other end of the first capacitor is used for grounding.

4. The circuit of claim 2 or 3, characterized in that, The current sensor comprises a current sensing amplifier.

5. The circuit of claim 1, wherein, The power supply switch module comprises a first resistor, a first switch unit and a second switch unit; one end of the first resistor is connected to the current sampling module, and the other end of the first resistor is connected to one end of the first switch unit; a control end of the first switch unit is connected to the control module, the other end of the first switch unit is used for connecting the direct current device and grounding; a control end of the second switch unit is connected between the other end of the first resistor and one end of the first switch unit, one end of the second switch unit is connected to the current sampling module, and the other end of the second switch unit is used for connecting the direct current device.

6. The circuit of claim 1, wherein, The direct current overcurrent protection circuit further comprises a power module connected between the direct current power supply and the control module; wherein: the power module comprises a second resistor, a third resistor, a fourth resistor, a second capacitor, a polarity capacitor, a voltage stabilizing diode and a diode; a positive electrode of the diode is used for connecting the direct current power supply, a negative electrode of the diode is connected to a positive electrode of the polarity capacitor and one end of the second resistor respectively, the other end of the second resistor is connected to the control module, one end of the third resistor and a cathode of the voltage stabilizing diode respectively, and The other end of the third resistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to ground; the reference end of the voltage stabilizing diode is connected between the other end of the third resistor and one end of the fourth resistor; The anode of the voltage stabilizing diode and the negative pole of the polarity capacitor are connected to ground; one end of the second capacitor is connected between the other end of the second resistor and the control module, and the other end of the second capacitor is connected to ground.

7. The circuit of claim 1, wherein, The control module comprises an MCU; A first pin of the MCU is electrically connected to the control end of the power supply switch module, and a second pin of the MCU is electrically connected to the current sampling module.

8. The circuit of claim 1, wherein, The circuit further comprises a state indication module connected to the control module; the state indication module comprises a seventh resistor and a light emitting diode; One end of the seventh resistor is connected to the control module, the other end of the seventh resistor is connected to one end of the light emitting diode, and the other end of the light emitting diode is connected to ground.

9. An electronic circuit breaker characterized by, The direct current overcurrent protection circuit comprises the direct current overcurrent protection circuit according to any one of claims 1 to 8.

10. A direct current power supply system, characterized by, The direct current power supply is connected to each of the electronic circuit breakers, and each of the electronic circuit breakers is connected to each of the direct current devices one by one. The direct current power supply is connected to each of the electronic circuit breakers, and each of the electronic circuit breakers is connected to each of the direct current devices one by one.

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