Port security circuit, energy storage device and energy storage system

Abstract

The utility model provides a kind of port safety circuit, energy storage equipment and energy storage system, the port safety circuit is connected in the port being provided with load detection circuit, including voltage divider circuit and first switch circuit, voltage divider circuit is connected between the positive pole and the negative pole of port, the resistance value of voltage divider circuit is less than the resistance value of load detection circuit;First switch circuit is connected in the loop between voltage divider circuit and port;Wherein, when port is in use state, first switch circuit disconnects the loop between voltage divider circuit and port, or, when port is in standby state, first switch circuit connects the loop between voltage divider circuit and port.The port safety circuit is connected by setting resistance value less than the voltage divider circuit of load detection circuit, when port is in standby state, the loop of voltage divider circuit and port is connected using first switch circuit, so that port voltage is reduced, and the virtual voltage generated by load detection circuit and semiconductor leakage current is reduced.

Description

Technical Field

[0001] This utility model relates to the field of port security technology for energy storage devices, specifically to port security circuits, energy storage devices, and energy storage systems. Background Technology

[0002] In related technologies, when the battery pack of a BMS (Battery Management System) is in a dormant or powered-off state, a virtual voltage problem often occurs at the external port. This phenomenon is mainly caused by two factors. On the one hand, most BMS products place the MOSFET on the low side, and the presence of the load sensing circuit will cause a voltage to be generated at the external port. The value of this voltage is calculated by the voltage divider principle using the battery voltage, the internal resistance of the multimeter, and the load sensing resistor. On the other hand, the microampere-level leakage current of semiconductor devices, when flowing through high-resistance sensing equipment such as multimeters, will also form a virtual voltage.

[0003] While removing the load detection circuit in conventional solutions can alleviate the problem to some extent, it causes the BMS to lose its ability to determine the connection and removal of loads, affecting user experience. At the same time, it cannot solve the problem of virtual voltage caused by semiconductor leakage current, which poses a risk to the stable operation of the system. Utility Model Content

[0004] Embodiments of this utility model provide a port security circuit, an energy storage device, and an energy storage system, which can improve the technical problem of virtual voltage at ports.

[0005] According to a first aspect of this application, a port safety circuit is provided, connected to a port provided with a load detection circuit, including a voltage divider circuit and a first switching circuit. The voltage divider circuit is connected between the positive and negative terminals of the port, and the resistance of the voltage divider circuit is less than the resistance of the load detection circuit. The first switching circuit is connected to the loop between the voltage divider circuit and the port. When the port is in use, the first switching circuit disconnects the loop between the voltage divider circuit and the port; or, when the port is in standby mode, the first switching circuit connects the loop between the voltage divider circuit and the port.

[0006] In some examples, by incorporating a voltage divider circuit with a resistance less than that of the load detection circuit, when the port is in standby mode, the first switching circuit connects the loop. Through the voltage divider circuit and the load detection circuit, the voltage across the port is actually the voltage across the voltage divider circuit, resulting in a lower voltage. This significantly reduces the virtual voltage generated by "leakage current × multimeter internal resistance," thus solving the problem of a large virtual voltage at the port in standby mode due to the presence of the load detection circuit and leakage current, and improving port safety. Furthermore, the entire circuit consists of a voltage divider circuit and a first switching circuit, making it simple in structure and easy to implement and integrate into existing circuit systems.

[0007] In one embodiment, the voltage divider circuit includes a plurality of voltage divider resistors connected in series.

[0008] In some cases, by using multiple series-connected voltage divider resistors to form a voltage divider circuit, the total resistance value of the voltage divider circuit can be adjusted more flexibly. The appropriate number and value of voltage divider resistors can be selected and combined according to different load detection circuit resistance values ​​and port voltage requirements to meet the voltage division requirements. Furthermore, compared to a single large-value resistor, the structure of multiple resistors in series allows the others to maintain their voltage division function to a certain extent even if one resistor suffers minor damage, thus improving the reliability of the voltage divider circuit.

[0009] In one embodiment, the port security circuit further includes a reverse protection circuit connected between the positive and negative terminals.

[0010] In some cases, by setting up anti-reverse circuits, reverse conduction can be prevented from occurring in the circuit, thus preventing reverse current from causing impact damage to the voltage divider resistors connected in series in the voltage divider circuit, the switching elements of the first switching circuit, and the load detection circuit, ensuring the service life of each circuit component. At the same time, it effectively prevents abnormal circuit operation caused by reverse conduction, ensuring that the voltage divider circuit stably suppresses false voltage in the standby state, further enhancing the safety and stability of the port safety circuit.

[0011] In one embodiment, the first switching circuit includes a first switching transistor, the input and output terminals of which are connected to a loop between the voltage divider circuit and the port. The enable terminal of the first switching transistor is used to receive a first control level to turn the input and output terminals of the first switching transistor on or off.

[0012] In some examples, the first control level is received at the enable terminal of the first switch to control its on / off state, enabling precise response to port state changes. When the port is in use, the first control level turns the switch off, preventing the voltage divider circuit from affecting the normal operation of other circuits. When the port is in standby mode, the first control level turns the switch on, allowing the voltage divider circuit to function and suppressing false voltage. The on / off control of the loop is achieved through the first control level, resulting in fast response speed. Furthermore, the switch itself has low power consumption and high reliability, contributing to improved stability and energy efficiency of the entire port safety circuit.

[0013] In one embodiment, at least one first current-limiting resistor is connected to the input terminal of the first switching transistor, and the first current-limiting resistor is used to perform voltage division on the circuit at the input terminal of the first switching transistor; and / or,

[0014] The output terminal of the first switching transistor is connected to at least one second current-limiting resistor, which is used to divide the voltage of the circuit at the output terminal of the first switching transistor.

[0015] In some examples, by using a first current-limiting resistor to divide the voltage on the input side of the first switching transistor and a second current-limiting resistor to divide the voltage on the output side, the first switching transistor and other devices can be effectively protected from damage due to excessive voltage, thus improving the stability of the first switching circuit. By multiplexing the first and / or second current-limiting resistors with the voltage divider resistors, the number of components in the circuit is reduced, the circuit structure is simplified, and the cost is lowered, while ensuring the normal operation of the voltage divider circuit and the first switching circuit.

[0016] In one embodiment, the first switching circuit further includes a second switching transistor, the input terminal of which is connected to the enable terminal of the first switching transistor. The input terminal of the second switching transistor is used to output the first control level, the output terminal of the second switching transistor is grounded, and the enable terminal of the second switching transistor is used to receive a second control level, so as to turn the input terminal and the output terminal of the second switching transistor on or off.

[0017] In some examples, by adding a second switch, the control capability of the first switch is enhanced. The second switch can amplify or convert the second control level signal, so that even a weak control signal can reliably drive the first switch, thereby improving the circuit's response sensitivity to control signals. At the same time, the presence of the second switch achieves isolation of the control signal, preventing level fluctuations at the enable terminal of the first switch from affecting the control signal source, thus enhancing the circuit's anti-interference capability.

[0018] In one embodiment, the first switching circuit includes a current limiting circuit connected between the second control level and the enable terminal of the second switching transistor. The current limiting circuit is used to limit the voltage of the output signal from the second control level to the second switching transistor.

[0019] In some cases, limiting the signal voltage output from the second control level to the enable terminal of the second switch via a current-limiting circuit can effectively protect the second switch from damage due to excessive input voltage, thus ensuring its lifespan. Simultaneously, a stable input voltage ensures more reliable on / off states of the second switch, preventing malfunctions caused by voltage fluctuations. This, in turn, ensures the accuracy of the first switch's state switching, making the voltage divider circuit more stable in standby and operating states, and improving the overall reliability of the port safety circuit.

[0020] In one embodiment, a first bias circuit is provided between the input terminal and the enable terminal of the first switch; and / or, a second bias circuit is provided between the input terminal and the enable terminal of the second switch.

[0021] In some examples, by using a first bias circuit to provide a stable bias to the input and enable terminals of the first switch, the reliability of its switching between the on and off states can be ensured, preventing false on or false off due to voltage fluctuations; similarly, by using a second bias circuit to provide a suitable bias to the input and enable terminals of the second switch, the stability of its operating state can be improved.

[0022] In one embodiment, the port security circuit includes an enable output circuit for outputting a second control level.

[0023] In some examples, by enabling the output circuit to output a second control level, the operating state of the second switching transistor can be precisely controlled, thereby achieving effective control of the loop between the first switching transistor, the voltage divider circuit, and the port. This allows the voltage divider circuit to be connected promptly to reduce false voltage when the port is in standby mode, and to be disconnected promptly to reduce impact when in use, ensuring the orderly implementation of the port safety circuit function and improving the degree of automation control and reliability of the circuit.

[0024] In one embodiment, the enable output circuit includes a microcontroller, one I / O of which is connected to the enable terminal of the second switch.

[0025] In some examples, the second control level can be output through the microcontroller's I / O port to achieve intelligent control of the second switching transistor. The microcontroller can accurately determine the port status based on various detection signals, making the output of the second control level more timely and accurate, thereby improving the reliability of the on / off control of the first switching circuit. At the same time, the programmability of the microcontroller allows the circuit to flexibly adapt to different application scenarios. The status judgment logic or the output pattern of the control level can be adjusted simply by modifying the program, enhancing the versatility and scalability of the port safety circuit, further ensuring that the voltage divider circuit plays its role at the appropriate time, and effectively reducing port phantom voltage.

[0026] In one embodiment, the enable output circuit includes a second switching circuit, one end of which is connected to an external enable power supply, and the other end of which is connected to the enable terminal of the second switching transistor.

[0027] In some examples, by controlling the external enable power supply to output a second control level to the enable terminal of the second switch transistor through the second switching circuit, a stable drive voltage can be provided by the external enable power supply, ensuring stable switching of the state of the second switch transistor.

[0028] In one embodiment, the second switching circuit includes a self-locking switch, one end of which is connected to an external enabling power supply, and the other end of which is connected to the enabling terminal of the second switching transistor.

[0029] In some cases, by setting a self-locking switch, manual control of the second control level can be achieved. The operation is simple and intuitive, and users can flexibly switch the working state of the port according to actual needs. At the same time, the self-locking characteristic of the self-locking switch ensures the stable maintenance of the state, and the voltage divider circuit can be maintained in the connected or disconnected state without continuous operation, which improves the convenience of circuit use. In addition, the self-locking switch has a simple structure, low cost, and high reliability, which helps to reduce the overall cost of the port safety circuit.

[0030] Secondly, an energy storage device is provided, which includes the port safety circuit as described above and has all the beneficial effects of the port safety circuit, which will not be repeated here.

[0031] Thirdly, an energy storage system is provided, which includes the port security circuit or the energy storage device as described above, having all the beneficial effects of the port security circuit or the energy storage device, which will not be elaborated further here.

[0032] The beneficial effects of the embodiments of this utility model are as follows:

[0033] In this embodiment of the invention, the port safety circuit uses a voltage divider circuit with a resistance lower than that of the load detection circuit. When the port is in standby mode, a first switching circuit connects the voltage divider circuit and the port, reducing the port voltage and minimizing the virtual voltage generated by the load detection circuit and semiconductor leakage current. When the port is in use mode, the first switching circuit disconnects the voltage divider circuit from the port, preventing the voltage divider circuit from affecting normal operation. This retains the function of the load detection circuit while ensuring the safety and stability of the port in different states. Furthermore, this port safety circuit includes a voltage divider circuit and a first switching circuit, resulting in a simple circuit structure that reduces design and manufacturing complexity and helps control costs. Moreover, the function switching is achieved by the first switching circuit switching between the port's use and standby states, eliminating the need for multi-step logical operations or complex timing control. This clear logic and convenient operation reduce the probability of errors during control. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the first type of port security circuit provided in an embodiment of this utility model;

[0036] Figure 2This is a schematic diagram of the second type of port security circuit provided in an embodiment of this utility model;

[0037] Figure 3 This is a schematic diagram of a third type of port security circuit provided in an embodiment of this utility model;

[0038] Figure 4 This is a schematic diagram of the fourth port security circuit provided in an embodiment of this utility model;

[0039] Figure 5 This is a schematic diagram of the fifth port security circuit provided in an embodiment of this utility model;

[0040] Figure 6 This is a schematic diagram of the sixth port security circuit provided in an embodiment of this utility model;

[0041] Figure 7 This is a schematic diagram of the seventh port security circuit provided in an embodiment of this utility model;

[0042] Figure 8 This is a schematic diagram of the eighth port security circuit provided in an embodiment of this utility model;

[0043] Figure 9 This is a schematic diagram of the ninth port security circuit provided in an embodiment of this utility model;

[0044] Figure 10 This is a schematic diagram of the tenth port security circuit provided in an embodiment of this utility model.

[0045] Explanation of reference numerals in the attached figures:

[0046] 1. Voltage divider circuit; 11. Voltage divider resistor;

[0047] 2. First switching circuit; 21. First switching transistor; 211. First current-limiting resistor; 212. Second current-limiting resistor; 213. First bias circuit; 22. Second switching transistor; 221. Second bias circuit; 23. Current-limiting circuit;

[0048] 3. Reverse protection circuit;

[0049] 4. Enable output circuit; 41. Microcontroller; 42. Second switching circuit;

[0050] 5. Port; 51. Positive terminal; 52. Negative terminal;

[0051] 6. External enable power supply. Detailed Implementation

[0052] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of the present utility model and are not intended to limit the present utility model. In the present utility model, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0053] According to the first aspect of this application, referring to Figure 1 A port safety circuit is provided, connected to a port 5 equipped with a load detection circuit. The circuit includes a voltage divider circuit 1 and a first switching circuit 2. The voltage divider circuit 1 is connected between the positive terminal 51 and the negative terminal 52 of port 5, and the resistance of the voltage divider circuit 1 is less than the resistance of the load detection circuit. The first switching circuit 2 is connected to the loop between the voltage divider circuit 1 and port 5. When port 5 is in use, the first switching circuit 2 disconnects the loop between the voltage divider circuit 1 and port 5; or, when port 5 is in standby mode, the first switching circuit 2 connects the loop between the voltage divider circuit 1 and port 5.

[0054] In common designs of lightweight power-type BMS, MOSFETs are often placed on the low side (i.e., connected in series between the load and ground). Even when the battery pack is in a dormant shutdown state, there will still be voltage at external port 5, mainly due to two factors: First, the presence of the load sensing circuit. The voltage at port 5 can be calculated using the formula "battery voltage × multimeter internal resistance / (multimeter internal resistance + load sensing resistance)". The multimeter internal resistance is typically 10MΩ, and the load sensing resistance is in the MΩ range. This can cause a large voltage at the exposed charging port 5 of the application product, raising customer concerns about safety. Second, there is the leakage current (in the μA range) stored in the semiconductor device. When this leakage current flows through the multimeter, it generates a virtual voltage of "leakage current × multimeter internal resistance", which is also quite large.

[0055] It is understood that the port safety circuit in this embodiment mainly includes a voltage divider circuit 1 and a first switching circuit 2, which work together to control the virtual voltage at port 5. The voltage divider circuit 1 is connected between the positive terminal 51 and the negative terminal 52 of port 5. The resistance of the voltage divider circuit 1 is less than the resistance of the load detection circuit, such as the resistance of the voltage divider circuit 1 being in the KΩ range. When connected, it performs voltage division to reduce the voltage at port 5. The first switching circuit 2 is connected in the loop between the voltage divider circuit 1 and port 5. It switches the working mode according to the state of port 5. When port 5 is in use (such as charging or discharging), the first switching circuit 2 will disconnect the loop between the voltage divider circuit 1 and port 5 to prevent the voltage divider circuit 1 from affecting the normally operating circuit and ensure that port 5 can transmit energy according to the normal path. When port 5 is in standby mode (i.e., not charging or discharging), the first switching circuit 2 will connect the loop between the voltage divider circuit 1 and port 5, allowing the voltage divider circuit 1 to be connected between the positive terminal 51 and the negative terminal 52 of port 5.

[0056] In some examples, by connecting voltage divider circuit 1, and ensuring that the resistance of voltage divider circuit 1 is less than the resistance of the load detection circuit, when port 5 is in standby mode, the first switching circuit 2 connects the loop. Through voltage divider circuit 1 and the load detection circuit, the voltage across port 5 is actually the voltage across voltage divider circuit 1, resulting in a lower voltage. This significantly reduces the virtual voltage generated by "leakage current × multimeter internal resistance," thus solving the problem of a large virtual voltage at port 5 in standby mode due to the presence of the load detection circuit and leakage current, and improving the safety of port 5. Furthermore, the entire circuit consists of voltage divider circuit 1 and the first switching circuit 2, making it simple in structure and easy to implement and integrate into existing circuit systems.

[0057] Reference Figure 2 In some embodiments, the voltage divider circuit 1 includes a plurality of voltage divider resistors 11 connected in series.

[0058] It is understood that in this embodiment, the voltage divider circuit 1 is composed of multiple series-connected voltage divider resistors 11, and the resistance of the voltage divider circuit 1 is equal to the sum of the resistances of each voltage divider resistor 11. When port 5 is in standby mode, the first switch circuit 2 is connected to the loop, and the voltage divider circuit 1 composed of multiple series-connected voltage divider resistors 11 is connected between the positive terminal 51 and the negative terminal 52 of port 5.

[0059] In some examples, the voltage divider circuit 1 may include two voltage divider resistors 11 connected in series, such as resistors R1 and R4 connected in series, with a total resistance of R1 + R4; or, it may include three voltage divider resistors 11 connected in series, with a total resistance of the sum of the resistances of the three voltage divider resistors 11; or, it may include four voltage divider resistors 11 connected in series, with a total resistance of the sum of the resistances of the four voltage divider resistors 11; in addition, more numbers of series voltage divider resistors 11 may be set according to actual needs, such as five, six, etc.

[0060] In some examples, by using multiple series-connected voltage divider resistors 11 to form a voltage divider circuit 1, the total resistance value of the voltage divider circuit 1 can be adjusted more flexibly. The appropriate number and value of voltage divider resistors 11 can be selected and combined according to different load detection circuit resistance values ​​and port 5 voltage requirements to meet the voltage division requirements. At the same time, compared to a single large-value resistor, the structure of multiple resistors connected in series allows the other resistors to maintain their voltage division function to a certain extent even if one resistor suffers minor damage, thus improving the reliability of the voltage divider circuit 1.

[0061] Reference Figure 3 In some embodiments, the port security circuit further includes a reverse protection circuit 3 connected between the positive terminal 51 and the negative terminal 52.

[0062] Understandably, the reverse conduction protection circuit 3 is connected between the positive terminal 51 and the negative terminal 52 of port 5 to prevent reverse conduction of the circuit. The reverse conduction protection circuit 3 utilizes a device with unidirectional conductivity (such as a diode) or a specific switching structure. When the positive terminal 51 and the negative terminal 52 of port 5 are correctly connected, the circuit conducts normally and does not affect the operation of the voltage divider circuit 1 and the first switching circuit 2. However, when the current in the positive terminal 51 and the negative terminal 52 is reversed, the reverse conduction protection circuit 3 will be in a cut-off state, blocking the flow of reverse current and preventing reverse voltage from damaging the internal circuitry of port 5 and the connected load detection circuit.

[0063] In some examples, the reverse protection circuit 3 includes a diode, with the anode of the diode connected to the positive terminal 51 of port 5 and the cathode connected to the negative terminal 52 of port 5. Utilizing the diode's forward conduction and reverse cutoff characteristics, when the currents at the positive terminal 51 and the negative terminal 52 are reversed, the diode is cut off, preventing reverse current. Alternatively, the reverse protection circuit 3 includes a MOSFET, with the source and drain of the MOSFET connected between the positive terminal 51 and the negative terminal 52 in a specific direction, and in conjunction with a corresponding driving circuit, so that the MOSFET conducts when connected in the forward direction and is cut off when connected in the reverse direction, thus achieving the reverse protection function.

[0064] In some examples, by setting up the anti-reverse circuit 3, reverse conduction can be prevented from occurring in the circuit, thereby preventing reverse current from causing impact damage to the voltage divider resistor 11 connected in series in the voltage divider circuit 1, the switching element of the first switching circuit 2, and the load detection circuit, ensuring the service life of each circuit component. At the same time, it effectively prevents abnormal circuit operation caused by reverse conduction, ensuring that the voltage divider circuit 1 stably suppresses false voltage in the standby state of port 5, further enhancing the safety and stability of the port safety circuit.

[0065] Reference Figure 3In some embodiments, the first switching circuit 2 includes a first switching transistor 21, the input and output terminals of which are connected to a loop between the voltage divider circuit 1 and port 5. The enable terminal of the first switching transistor 21 is used to receive a first control level to turn the input and output terminals of the first switching transistor 21 on or off.

[0066] Understandably, the input and output terminals of the first switching transistor 21 are connected to the loop between the voltage divider circuit 1 and port 5, controlling the current flow and cutoff. The enable terminal of the first switching transistor 21 is used to receive a first control level, which determines the operating state of the first switching transistor 21. When the enable terminal receives a high level (or a low level, depending on the type of switching transistor), the input and output terminals of the first switching transistor 21 are connected, thereby connecting the loop between the voltage divider circuit 1 and port 5; when the enable terminal receives the opposite level signal, the input and output terminals of the first switching transistor 21 are disconnected, cutting off the loop between the voltage divider circuit 1 and port 5.

[0067] In some examples, the first switching transistor 21 is an N-channel MOSFET, with its source and drain connected to different nodes of the voltage divider circuit 1 and port 5 (the input is the source, and the output is the drain). The gate (enable terminal) receives the first control level, turning on when high and turning off when low. Alternatively, the first switching transistor 21 is a P-channel MOSFET, with its source and drain connected to the voltage divider circuit 1 and port 5. The gate receives the first control level, turning on when low and turning off when high. Alternatively, the first switching transistor 21 is an NPN transistor, with its emitter and collector connected to the voltage divider circuit 1 and port 5 (the input is the emitter, and the output is the collector). The base (enable terminal) receives the first control level through a resistor, turning on when high and turning off when low.

[0068] In some examples, the first control level is received at the enable terminal of the first switch 21 to control its on / off state, enabling precise response to changes in the state of port 5. When port 5 is in use, the first control level turns the switch off, preventing the voltage divider circuit 1 from affecting the normal operation of other circuits. When port 5 is in standby state, the control level turns the switch on, allowing the voltage divider circuit 1 to function and suppressing false voltage. The on / off control of the loop is achieved through the first control level, resulting in fast response speed. Furthermore, the switch itself has low power consumption and high reliability, contributing to improved stability and energy efficiency of the entire port safety circuit.

[0069] Reference Figure 2 In some embodiments, at least one first current-limiting resistor 211 is connected to the input terminal of the first switching transistor 21. The first current-limiting resistor 211 is used to divide the voltage of the circuit at the input terminal of the first switching transistor 21; and / or,

[0070] At least one second current-limiting resistor 212 is connected to the output terminal of the first switching transistor 21. The second current-limiting resistor 212 is used to divide the voltage of the circuit at the output terminal of the first switching transistor 21.

[0071] Understandably, the first current-limiting resistor 211 is connected to the input terminal of the first switching transistor 21 (for example, if the first switching transistor 21 is a MOSFET, the input terminal can be the gate; if it is a transistor, the input terminal can be the base) to divide the voltage of the circuit at the input terminal of the first switching transistor 21, preventing excessively high voltage from being directly applied to the circuit on one side of the input terminal of the first switching transistor 21 and causing damage to the device; the second current-limiting resistor 212 is connected to the output terminal of the first switching transistor 21 (for example, the drain or source of a MOSFET, the collector or emitter of a transistor), and is also used to divide the voltage of the circuit on the output terminal side, controlling the voltage of the circuit on the output terminal side within a safe range.

[0072] Meanwhile, the first current-limiting resistor 211 and the second current-limiting resistor 212 can be reused with the voltage-dividing resistor 11 in the voltage divider circuit 1. That is, the same resistor can perform the function of current limiting and voltage division, and also serve as part of multiple series voltage-dividing resistors 11 in the voltage divider circuit 1, without the need for additional components.

[0073] In some examples, the first switching transistor 21 is a bipolar transistor, with a first current-limiting resistor 211 connected in series at its emitter (input terminal). This resistor serves both as a voltage divider for the emitter-side circuit and as the voltage divider resistor 11 in voltage divider circuit 1. A second current-limiting resistor 212 is connected in series at its collector (output terminal). This resistor serves both as a voltage divider for the collector-side circuit and as the voltage divider resistor 11 in voltage divider circuit 1.

[0074] In some examples, by using the first current-limiting resistor 211 to divide the voltage on the input side of the first switching transistor 21 and the second current-limiting resistor 212 to divide the voltage on the output side, the first switching transistor 21 and other devices can be effectively protected from damage due to excessive voltage, thus improving the stability of the first switching circuit 2. By multiplexing the first current-limiting resistor 211 and / or the second current-limiting resistor 212 with the voltage divider resistor 11, the number of components in the circuit is reduced, the circuit structure is simplified, and the cost is lowered, while ensuring the normal operation of the voltage divider circuit 1 and the first switching circuit 2.

[0075] Reference Figure 4 In some embodiments, the first switching circuit 2 further includes a second switching transistor 22. The input terminal of the second switching transistor 22 is connected to the enable terminal of the first switching transistor 21. The input terminal of the second switching transistor 22 is used to output a first control level. The output terminal of the second switching transistor 22 is grounded. The enable terminal of the second switching transistor 22 is used to receive a second control level so that the input terminal and the output terminal of the second switching transistor 22 are turned on or off.

[0076] It is understandable that the input terminal of the second switch 22 is connected to the enable terminal of the first switch 21 to output a first control level to the enable terminal of the first switch 21; the output terminal of the second switch 22 is directly grounded to form a reference point for the loop; and the enable terminal of the second switch 22 is used to receive a second control level, which determines the on or off state of the second switch 22, thereby indirectly controlling the working state of the first switch 21.

[0077] When the second control level turns on the second switch 22, its input and output (ground) terminals are connected. At this time, the enable terminal of the first switch 21 is pulled low (grounded), and the first control level is low, turning on the input and output terminals of the first switch 21. This connects the voltage divider circuit 1 and port 5. When the second control level turns off the second switch 22, the path between its input and output (ground) terminals is blocked. The enable terminal of the first switch 21 is no longer grounded, and the first control level can be high (e.g., provided by a battery), disconnecting the input and output terminals of the first switch 21. This cuts off the circuit between the voltage divider circuit 1 and port 5. Based on the switching characteristics of the transistors, the second switch 22 acts as a "pre-controller" for the first switch 21, changing the level of the enable terminal of the first switch 21 through its own state.

[0078] In some examples, the first switch 21 is a PNP transistor (enabled by a low level), and the second switch 22 is an NPN transistor (enabled by a high level). The collector (input) of the second switch 22 is connected to the base (enable) of the first switch 21, and its emitter (output) is grounded. The base (enable) receives a second control level. When the second control level is high, the second switch 22 is turned on, the base of the first switch 21 is pulled low, and the first switch 21 is turned on. When the second control level is low, the second switch 22 is turned off, the base potential of the first switch 21 rises, and the first switch 21 is turned off.

[0079] In some examples, by adding a second switch 22, the control capability of the first switch 21 is enhanced. The second switch 22 can amplify or convert the second control level signal, so that even a weak control signal can reliably drive the first switch 21, thereby improving the circuit's response sensitivity to control signals. At the same time, the presence of the second switch 22 achieves the isolation of control signals, preventing level fluctuations at the enable terminal of the first switch 21 from affecting the control signal source, thus enhancing the circuit's anti-interference capability.

[0080] Reference Figure 5In some embodiments, the first switching circuit 2 includes a current limiting circuit 23 connected between the second control level and the enable terminal of the second switching transistor 22. The current limiting circuit 23 is used to limit the voltage of the output signal from the second control level to the second switching transistor 22.

[0081] Understandably, the current limiting circuit 23 is connected between the second control level and the enable terminal of the second switching transistor 22 to limit the signal voltage transmitted from the second control level to the enable terminal of the second switching transistor 22. By utilizing the voltage divider characteristics of resistors or the clamping effect of voltage regulators, the current limiting circuit 23, through its own circuit structure, controls the voltage output to the enable terminal of the second switching transistor 22 within a safe range when the voltage of the second control level is too high, thus preventing damage to the second switching transistor 22 due to excessive voltage.

[0082] In some examples, the current limiting circuit 23 uses one or more current limiting resistors R3, which are connected in series between the second control level and the enable terminal of the second switching transistor 22. Utilizing the principle of resistor voltage division, when the second control level voltage is high, the resistor shares part of the voltage, thus reducing the voltage applied to the enable terminal of the second switching transistor 22. Alternatively, the current limiting circuit 23 includes a current limiting resistor and a Zener diode. The Zener diode is connected in reverse parallel between the enable terminal of the second switching transistor 22 and ground, and the current limiting resistor is connected in series between the second control level and the enable terminal. When the input voltage exceeds the regulated value, the Zener diode breaks down and conducts, clamping the voltage at the enable terminal to the regulated value.

[0083] In some examples, limiting the signal voltage output from the second control level to the enable terminal of the second switch 22 by the current limiting circuit 23 can effectively protect the second switch 22, preventing it from being damaged by excessive input voltage and ensuring its service life. Simultaneously, a stable input voltage ensures more reliable on / off states of the second switch 22, avoiding malfunctions caused by voltage fluctuations. This, in turn, ensures the accuracy of the state switching of the first switch 21, making the switching of the voltage divider circuit 1 between standby and operating states more stable and improving the reliability of the entire port safety circuit.

[0084] Reference Figure 6 and Figure 7 In some embodiments, a first bias circuit 213 is provided between the input terminal and the enable terminal of the first switch 21; and / or, a second bias circuit 221 is provided between the input terminal and the enable terminal of the second switch 22.

[0085] Understandably, taking a transistor as an example, the first switching transistor 21 is a PNP transistor, and the first bias circuit 213 set between its input terminal (emitter) and enable terminal (base) is used to provide a suitable bias voltage for the PNP transistor to ensure that it can work stably in the on or off state; the second switching transistor 22 is an NPN transistor, and the second bias circuit 221 set between its input terminal (collector) and enable terminal (base) is also used to provide a suitable bias condition for the NPN transistor to ensure the stability of its working state.

[0086] For the first bias circuit 213 (PNP type first switching transistor 21): The PNP type transistor needs to be turned on when the base voltage is lower than the emitter voltage by a certain value (usually about 0.7V). The first bias circuit 213 includes several resistors, such as a bias resistor R2 connected between the emitter and the base. When the emitter is connected to a high level, the bias resistor will reduce the base voltage. When the conduction condition is met, the transistor will turn on; otherwise, it will be turned off. This circuit can stabilize the voltage difference between the base and the emitter, ensuring that the transistor works normally.

[0087] For the second bias circuit 221 (NPN type second switch 22): the NPN type transistor requires the base voltage to be higher than the emitter voltage by a certain value (usually about 0.7V) to conduct. The second bias circuit 221 includes several resistors, such as a bias resistor R5 connected between the base and the collector. When the base is connected to a high level, the bias resistor can stabilize the voltage relationship between the base and the collector, ensuring that the transistor conducts when the conduction condition is met and is cut off when it is not met, thus ensuring that the transistor works normally.

[0088] In some examples, the first bias circuit 213 provides a stable bias to the input and enable terminals of the first switch 21, ensuring the reliability of its switching between the on and off states and preventing false on or false off due to voltage fluctuations; similarly, the second bias circuit 221 provides a suitable bias to the input and enable terminals of the second switch 22, which can also improve the stability of its operating state.

[0089] Reference Figure 8 In some embodiments, the port security circuit includes an enable output circuit 4 for outputting a second control level.

[0090] It is understandable that the enable output circuit 4 outputs a second control level, which is transmitted to the enable terminal of the second switch 22 to control the conduction or disconnection state of the second switch 22, thereby indirectly affecting the working state of the first switch 21, and finally realizing the on / off control of the loop between the voltage divider circuit 1 and port 5.

[0091] From a technical perspective, the enable output circuit 4 can generate a corresponding second control level based on the state of port 5 (usage state or standby state). When port 5 is in standby state, the second control level output by the enable output circuit 4 turns on the second switch 22, thereby turning on the first switch 21, connecting the loop between the voltage divider circuit 1 and port 5, and enabling the voltage divider circuit 1 to suppress false voltage. When port 5 is in use state, the second control level output by the enable output circuit 4 turns off the second switch 22, thereby turning off the first switch 21, cutting off the loop between the voltage divider circuit 1 and port 5, and preventing the voltage divider circuit 1 from interfering with the normal operation of port 5.

[0092] In some examples, the enable output circuit 4 may include a level signal generator that can directly output a high or low level as a second control level based on an external trigger signal (such as the working status detection signal of port 5); or, the enable output circuit 4 may be composed of a microcontroller or microcontroller 41, which, after determining the status of port 5 through a program, such as connecting to a load detection circuit to obtain the usage status of port 5, outputs the corresponding second control level from its I / O port; or, the enable output circuit 4 may be a circuit composed of comparators that outputs the corresponding second control level by comparing the voltage or current signal of port 5 with a preset threshold.

[0093] In some examples, by enabling the output circuit 4 to output a second control level, the operating state of the second switching transistor 22 can be precisely controlled, thereby achieving effective control of the loop between the first switching transistor 21, the voltage divider circuit 1, and port 5. This ensures that when port 5 is in standby mode, the voltage divider circuit 1 can be connected in a timely manner to reduce false voltage, and when in use mode, the voltage divider circuit 1 can be disconnected in a timely manner to reduce the impact, ensuring the orderly implementation of the port safety circuit function and improving the degree of automation control and reliability of the circuit.

[0094] Reference Figure 9 In some embodiments, the enable output circuit 4 includes a microcontroller 41, one I / O of which is connected to the enable terminal of the second switch 22.

[0095] It is understood that the enable output circuit 4 in this embodiment uses a microcontroller 41 as its core component. The microcontroller 41 is directly connected to the enable terminal of the second switch 22 through one of its I / O (input / output) ports 5. The main function of this I / O port is to output a second control level. From a technical perspective, the microcontroller 41 can determine the current state of port 5 (use state or standby state) through its internal program: when it determines that port 5 is in standby state, the microcontroller 41 controls its I / O port to output a specific level (such as a high level, depending on the type of the second switch 22), causing the second switch 22 to turn off, thereby causing the first switch 21 to turn off, breaking the loop between the voltage divider circuit 1 and port 5; when it determines that port 5 is in use state, the microcontroller 41 controls the I / O port to output an opposite level (such as a low level), causing the second switch 22 to turn on, the first switch 21 to turn on, and the loop between the voltage divider circuit 1 and port 5 to be connected.

[0096] In some examples, the microcontroller 41 determines the state of port 5 by obtaining the detection results of the load detection circuit or by detecting voltage changes (such as voltage rise during charging), current changes (such as current generation during discharging) or receiving status signals sent by external devices (such as charger connection signals) at port 5. After internal logic processing, it outputs the corresponding second control level from the I / O port. For example, when the microcontroller 41 detects that there is charging current flowing into port 5, it determines that it is in use, and the I / O port outputs a low level, causing the second switch 22 to turn off; when no current is detected and the voltage at port 5 is stable near the battery voltage, it determines that it is in standby mode, and the I / O port outputs a high level to the base (enable terminal) of the NPN type second switch 22, causing the second switch 22 to turn on.

[0097] In some examples, the second control level can be output through the I / O port of the microcontroller 41 to achieve intelligent control of the second switching transistor 22. The microcontroller 41 can accurately determine the state of port 5 based on various detection signals, making the output of the second control level more timely and accurate, thereby improving the reliability of the on / off control of the first switching circuit 2. At the same time, the programmability of the microcontroller 41 allows the circuit to flexibly adapt to different application scenarios. The state judgment logic or the output pattern of the control level can be adjusted simply by modifying the program, which enhances the versatility and expandability of the port safety circuit and further ensures that the voltage divider circuit 1 plays its role at the appropriate time, effectively reducing the false voltage at port 5.

[0098] Reference Figure 10 In some embodiments, the enable output circuit 4 includes a second switch circuit 42, one end of which is connected to an external enable power supply 6, and the other end of which is connected to the enable terminal of the second switch transistor 22.

[0099] Understandably, the second switching circuit 42 connects to the external enabling power supply 6 and the enabling terminal of the second switching transistor 22, controlling the external enabling power supply 6 to output a second control level to the enabling terminal of the second switching transistor 22. When the second switching circuit 42 is turned on, the voltage of the external enabling power supply 6 can be transmitted to the enabling terminal of the second switching transistor 22, forming the second control level, thereby controlling the state of the second switching transistor 22; when the second switching circuit 42 is turned off, the path between the external enabling power supply 6 and the enabling terminal of the second switching transistor 22 is cut off, the enabling terminal of the second switching transistor 22 loses the driving signal, and its state changes accordingly.

[0100] In some examples, the second switching circuit 42 controls the external enabling power supply 6 to output a second control level to the enable terminal of the second switching transistor 22, which can utilize the external enabling power supply 6 to provide a stable driving voltage and ensure stable switching of the state of the second switching transistor 22.

[0101] Reference Figure 10 In some embodiments, the second switching circuit 42 includes a self-locking switch, one end of which is connected to an external enabling power supply 6, and the other end of which is connected to the enabling terminal of the second switching transistor 22.

[0102] Understandably, one end of the self-locking switch is connected to the external enabling power supply 6, and the other end is connected to the enabling terminal of the second switching transistor 22. The self-locking switch has a self-locking function, meaning that it remains in the conducting state after being pressed, and returns to the de-energized state when pressed again, maintaining the current state without the need for continuous external force. When the self-locking switch is in the conducting state, the voltage of the external enabling power supply 6 can be transmitted to the enabling terminal of the second switching transistor 22 through the self-locking switch, forming a second control level, thereby controlling the operating state of the second switching transistor 22; when the self-locking switch is in the de-energized state, the path between the external enabling power supply 6 and the enabling terminal of the second switching transistor 22 is cut off, the second control level cannot be transmitted, and the state of the second switching transistor 22 changes accordingly.

[0103] When port 5 is in standby mode, pressing the self-locking switch turns it on. The voltage from the external enabling power supply 6 is transmitted to the enable terminal of the second switching transistor 22 through the self-locking switch, turning on the second switching transistor 22. This, in turn, turns on the first switching transistor 21, connecting the voltage divider circuit 1 and port 5, thus reducing the false voltage at port 5. When port 5 needs to be put into use, pressing the self-locking switch again turns it off. The external enabling power supply 6 can no longer provide voltage to the enable terminal of the second switching transistor 22, causing the second switching transistor 22 to turn off. This causes the first switching transistor 21 to turn off, cutting off the circuit between the voltage divider circuit 1 and port 5, preventing the voltage divider circuit 1 from interfering with the normal operation of port 5.

[0104] In some examples, by setting a self-locking switch, manual control of the second control level can be achieved. The operation is simple and intuitive, and users can flexibly switch the working state of port 5 according to actual needs. At the same time, the self-locking characteristic of the self-locking switch ensures the stable maintenance of the state. The voltage divider circuit 1 can be maintained in the connected or disconnected state without continuous operation, which improves the convenience of circuit use. In addition, the self-locking switch has a simple structure, low cost, and high reliability, which helps to reduce the overall cost of the port safety circuit.

[0105] According to a second aspect of this application, an energy storage device is provided, which includes the port safety circuit as described above and has all the beneficial effects of the port safety circuit, which will not be repeated here.

[0106] According to a third aspect of this application, an energy storage system is provided, which includes the port security circuit as described above or the energy storage device as described above, having all the beneficial effects of the port security circuit or the energy storage device, which will not be repeated here.

[0107] The embodiments of this utility model have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A port safety circuit, connected to a port (5) equipped with a load detection circuit, characterized in that, include: A voltage divider circuit (1) is connected between the positive terminal (51) and the negative terminal (52) of the port (5). The resistance of the voltage divider circuit (1) is less than the resistance of the load detection circuit. The first switching circuit (2) is a loop connected between the voltage divider circuit (1) and the port (5); When the port (5) is in use, the first switch circuit (2) disconnects the loop between the voltage divider circuit (1) and the port (5). When the port (5) is in standby mode, the first switch circuit (2) connects the loop between the voltage divider circuit (1) and the port (5).

2. The port security circuit according to claim 1, characterized in that, The voltage divider circuit (1) includes multiple voltage divider resistors (11) connected in series.

3. The port security circuit according to claim 1, characterized in that, The port security circuit also includes an anti-reverse circuit (3), which is connected between the positive terminal (51) and the negative terminal (52) of the port (5).

4. The port security circuit according to any one of claims 1-3, characterized in that, The first switching circuit (2) includes a first switching transistor (21). The input and output terminals of the first switching transistor (21) are connected to the loop between the voltage divider circuit (1) and the port (5). The enable terminal of the first switching transistor (21) is used to receive a first control level so that the input and output terminals of the first switching transistor (21) are turned on or off.

5. The port security circuit according to claim 4, characterized in that, The input terminal of the first switching transistor (21) is connected to at least one first current-limiting resistor (211), which is used to divide the voltage of the circuit at the input terminal of the first switching transistor (21); and / or, The output terminal of the first switching transistor (21) is connected to at least one second current-limiting resistor (212), which is used to divide the voltage of the circuit at the output terminal of the first switching transistor (21).

6. The port security circuit according to claim 4, characterized in that, The first switching circuit (2) further includes a second switching transistor (22). The input terminal of the second switching transistor (22) is connected to the enable terminal of the first switching transistor (21). The input terminal of the second switching transistor (22) is used to output the first control level. The output terminal of the second switching transistor (22) is grounded. The enable terminal of the second switching transistor (22) is used to receive the second control level so that the input terminal and the output terminal of the second switching transistor (22) are turned on or off.

7. The port security circuit according to claim 6, characterized in that, The first switching circuit (2) includes a current limiting circuit (23), which is connected between the second control level and the enable terminal of the second switching transistor (22). The current limiting circuit (23) is used to limit the voltage of the output signal of the second control level to the second switching transistor (22).

8. The port security circuit according to claim 6, characterized in that, A first bias circuit (213) is provided between the input terminal and the enable terminal of the first switching transistor (21); and / or, A second bias circuit (221) is provided between the input terminal and the enable terminal of the second switch (22).

9. The port security circuit according to claim 6, characterized in that, The port security circuit includes an enable output circuit (4) for outputting a second control level.

10. The port security circuit according to claim 9, characterized in that, The enable output circuit (4) includes a microcontroller (41), one I / O of which is connected to the enable terminal of the second switch (22).

11. The port security circuit according to claim 9, characterized in that, The enable output circuit (4) includes a second switch circuit (42), one end of which is connected to an external enable power supply (6), and the other end of which is connected to the enable terminal of the second switch tube (22).

12. The port security circuit according to claim 11, characterized in that, The second switching circuit (42) includes a self-locking switch, one end of which is connected to an external enabling power supply (6), and the other end of which is connected to the enabling terminal of the second switching transistor (22).

13. An energy storage device, characterized in that, Includes a port security circuit as described in any one of claims 1-12.

14. An energy storage system, characterized in that, Includes the port security circuit as described in any one of claims 1-12 or the energy storage device as described in claim 13.

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