Alternating current and direct current dual-purpose safety protection circuit and electronic fuse

Abstract

The invention discloses an alternating current and direct current dual-purpose safety protection circuit and an electronic fuse. The safety protection circuit comprises a monitoring and driving module and a safety protection module, and the first end of the monitoring and driving module and the first end of the safety protection module are both used for being connected with the positive electrode of a power supply; the second end of the monitoring and driving module is electrically connected with the second end of the safety protection module; the third end of the safety protection module is connected with the cathode of the power supply; the monitoring and driving module is used for monitoring the line current of the safety protection circuit; when it is determined that the line current meets the safety control condition, a safety driving signal corresponding to the line current is generated; and the safety protection module is used for executing safety control operation according to the safety driving signal, and the safety control operation is used for cutting off a connection circuit between the safety protection circuit and the power supply. Therefore, the design circuit of the electronic fuse can be simplified, the production cost of the electronic fuse can be reduced, and the anti-electromagnetic and anti-interference capabilities of the electronic fuse can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical system protection, and in particular to a safety protection circuit and an electronic fuse that can be used for both AC and DC. Background Art

[0002] In the field of electrical system protection, although traditional mechanical fuses have a certain protection effect, they have gradually been unable to meet the requirements of modern high-demand circuit protection due to the need for frequent replacement and performance limitations under specific conditions.

[0003] As an emerging technology, electronic fuses have the advantages of fast response and resetability. However, compared with traditional mechanical fuses, the design circuit of electronic fuses is more complex, the manufacturing cost is higher, and due to their electronic control characteristics, electronic fuses are prone to electromagnetic interference, which may affect the normal operation of other electronic components. In addition, conventional electronic fuses often rely on external power supplies or grounding, which constitutes an obstacle to use in some application scenarios. Therefore, it is particularly important to provide a corresponding solution to the technical problems existing in existing electronic fuses. Summary of the Invention

[0004] The present invention provides a safety protection circuit and an electronic fuse that can be used for both AC and DC, which can simplify the design circuit of the electronic fuse, reduce its production cost, and improve the electromagnetic resistance and anti-interference ability of the electronic fuse.

[0005] To solve the above technical problems, in a first aspect of the present invention, a safety protection circuit that can be used for both AC and DC is disclosed. The safety protection circuit includes a monitoring and driving module and a safety protection module, wherein: The first ends of the monitoring and driving module and the safety protection module are both used to connect to the positive pole of the power supply; the second end of the monitoring and driving module is electrically connected to the second end of the safety protection module; the third end of the safety protection module is used to connect to the negative pole of the power supply; The monitoring and driving module is used to monitor the line current of the safety protection circuit; and when it is determined that the line current meets a preset safety control condition, a safety driving signal corresponding to the line current is generated; The safety protection module is used to perform a safety control operation according to the safety driving signal after receiving the safety driving signal, and the safety control operation is used to cut off the connection circuit between the safety protection circuit and the power supply.

[0006] As an optional implementation manner, in the first aspect of the present invention, the monitoring and driving module includes a monitoring sub-module and a driving sub-module, wherein: The first ends of the monitoring sub-module and the driving sub-module are both used to connect to the positive pole of the power supply; the second ends of the monitoring sub-module and the driving sub-module are both electrically connected to the second end of the safety protection module; The monitoring sub-module is used to monitor the line current of the safety protection circuit; and transmit the current information of the line current to the driving sub-module; the current information is used to indicate the current state of the line current, and the current state includes a normal state or an abnormal state, and the abnormal state includes overload or short circuit; The driving sub-module is used to generate a safety driving signal corresponding to the current information when the current information indicates that a preset safety control condition is met; Wherein, the current information indicating that the preset safety control condition is met specifically includes that the current information indicates that the line current has the overload or the short circuit.

[0007] As an optional implementation manner, in the first aspect of the present invention, the monitoring sub-module includes a voltage sampling resistor, a filtering capacitor, a voltage stabilizing resistor, and a first voltage stabilizing diode, wherein: The first ends of the voltage sampling resistor, the filtering capacitor, and the positive pole of the first voltage stabilizing diode are all used to connect to the positive pole of the power supply; the negative pole of the first voltage stabilizing diode is electrically connected to the first end of the voltage stabilizing resistor; the second ends of the voltage sampling resistor, the filtering capacitor, and the voltage stabilizing resistor are all electrically connected to the second end of the safety protection module; The voltage sampling resistor is used to monitor the line current of the safety protection circuit; The filtering capacitor is used to perform filtering processing on the input voltage of the power supply to eliminate extremely narrow pulses existing in the safety protection circuit; The first voltage stabilizing diode is used to perform rectification and / or voltage stabilization processing on the input voltage; The voltage stabilizing resistor is used to perform current limiting and voltage dividing processing on the input voltage.

[0008] As an optional implementation manner, in the first aspect of the present invention, the driving sub-module includes a resonance unit and a target triode, and the safety protection module includes a voltage stabilizing sub-module, a control sub-module, and a protection sub-module, wherein: The first end of the resonance unit is used to connect to the positive pole of the power supply; the second ends of the voltage sampling resistor and the resonance unit are both electrically connected to the first end of the protection sub-module; the third end of the resonance unit is electrically connected to the base of the target triode; the fourth end of the resonance unit and the collector of the target triode are both electrically connected to the first end of the voltage stabilizing sub-module; The emitter of the target triode and the first end of the control sub-module are both electrically connected to the second end of the protection sub-module; the second end of the control sub-module is electrically connected to the second end of the voltage regulation sub-module; the third end of the voltage regulation sub-module is electrically connected to the third end of the protection sub-module.

[0009] As an optional implementation manner, in the first aspect of the present invention, the resonance unit is used to adjust the oscillation frequency of the safety protection circuit; The target triode is used to perform state switching according to the line current fed back by the voltage sampling resistor, and generate a target signal for the protection sub-module according to the corresponding state switching result; the state switching is used to switch the conduction state and the cut-off state of the target triode; the target signal includes a drive signal corresponding to the conduction state or a cut-off signal corresponding to the cut-off state; The voltage regulation sub-module is used to perform voltage regulation on the current flowing through the voltage regulation sub-module; The control sub-module is used to adjust the maintenance working time of the protection sub-module; The protection sub-module is used to, when the target triode switches to the conduction state, switch the protection sub-module from the on-state to the off-state according to the drive signal; The protection sub-module is further used to, when the target triode switches to the cut-off state, switch the protection sub-module from the off-state to the on-state according to the cut-off signal.

[0010] As an optional implementation manner, in the first aspect of the present invention, the target triode is a PNP type triode or an NPN type triode; and when the target triode is a PNP type triode, the voltage regulation sub-module includes a second voltage regulating diode; the control sub-module includes a first control capacitor, wherein: The collector of the target triode is electrically connected to the negative electrode of the second voltage regulating diode; the positive electrode of the second voltage regulating diode is respectively electrically connected to the third end of the protection sub-module and the negative electrode of the control capacitor; the emitter of the target triode and the positive electrode of the first control capacitor are both used to connect to the positive electrode of the power supply.

[0011] As an optional implementation manner, in the first aspect of the present invention, when the target triode is an NPN type triode, the voltage regulation sub-module includes a third voltage regulating diode; the control sub-module includes a second control capacitor, wherein: The collector of the target triode is electrically connected to the positive electrode of the third voltage stabilizing diode; the negative electrode of the third voltage stabilizing diode is respectively electrically connected to the third terminal of the protection sub-module and the positive electrode of the control capacitor; the emitter of the target triode and the negative electrode of the second control capacitor are both used to connect to the positive electrode of the power supply.

[0012] As an optional implementation manner, in the first aspect of the present invention, the protection sub-module includes a first relay or a second relay; the first relay includes an alarm output function, and the second relay does not include the alarm output function; The protection sub-module is further configured to, when the protection sub-module is the first relay and when the target triode switches to the conducting state, output an alarm signal corresponding to the line current to indicate that there is current overload or current short circuit in the safety protection circuit.

[0013] As an optional implementation manner, in the first aspect of the present invention, the protection sub-module includes a target MOS transistor, a current limiting resistor and a voltage dividing resistor, wherein: The source electrode of the target MOS transistor is used to connect to the positive electrode of the power supply; the gate electrode of the target MOS transistor is respectively electrically connected to the first end of the current limiting resistor and the first end of the voltage dividing resistor; the drain electrode of the target MOS transistor is respectively electrically connected to the first end of the voltage sampling resistor, the first end of the voltage stabilizing resistor and the first end of the resonance unit; The second end of the current limiting resistor is used to be grounded; the second end of the voltage dividing resistor is used to connect to the negative electrode of the power supply; The target MOS transistor is configured to, when the target triode switches to the conducting state, switch the target MOS transistor from the conducting state to the cut-off state according to the driving signal; and is further configured to, when the target triode switches to the cut-off state, switch the target MOS transistor from the cut-off state to the conducting state according to the driving signal; The current limiting resistor is configured to perform a current limiting operation on the current flowing through the target MOS transistor to protect the target MOS transistor; The voltage dividing resistor is configured to perform a voltage dividing operation on the current flowing through the target MOS transistor and is further configured to control the on-off of the target MOS transistor.

[0014] A second aspect of the present invention discloses an electronic fuse, the electronic fuse includes a device main body, and the electronic fuse includes a safety protection circuit for both AC and DC as disclosed in the first aspect of the present invention.

[0015] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: In an embodiment of the present invention, a safety protection circuit for both AC and DC power is provided. The safety protection circuit includes a monitoring and driving module and a safety protection module, where: the first ends of both the monitoring and driving module and the safety protection module are used to connect to the positive pole of the power supply; the second end of the monitoring and driving module is electrically connected to the second end of the safety protection module; the third end of the safety protection module is used to connect to the negative pole of the power supply; the monitoring and driving module is used to monitor the line current of the safety protection circuit; and when it is determined that the line current meets the preset safety control conditions, a safety driving signal corresponding to the line current is generated; the safety protection module is used to, after receiving the safety driving signal, perform a safety control operation according to the safety driving signal, and the safety control operation is used to cut off the connection circuit between the safety protection circuit and the power supply. It can be seen that by implementing the present invention, the line current of the safety protection circuit can be monitored in real time, improving the monitoring timeliness of the line current; when the line current exceeds the safety control conditions, a corresponding safety driving signal can be quickly generated, thereby driving the safety protection module to perform a safety control operation, improving the response speed to abnormal situations in the safety protection circuit; through the collaborative work of the monitoring and driving module and the safety protection module, effective monitoring and safety supervision of the line current are realized, significantly enhancing the use safety and reliability of the safety protection circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings without creative efforts based on these drawings.

[0017] Figure 1 FIG. is a schematic structural diagram of a safety protection circuit for both AC and DC power disclosed in an embodiment of the present invention; Figure 2 FIG. is a schematic structural diagram of another safety protection circuit for both AC and DC power disclosed in an embodiment of the present invention; Figure 3 FIG. is a schematic structural diagram of yet another safety protection circuit for both AC and DC power disclosed in an embodiment of the present invention; Figure 4 FIG. is a schematic structural diagram of another safety protection circuit for both AC and DC power disclosed in an embodiment of the present invention; Figure 5 FIG. is a schematic structural diagram of yet another safety protection circuit for both AC and DC power disclosed in an embodiment of the present invention; Figure 6 FIG. is a schematic structural diagram of another safety protection circuit for both AC and DC power disclosed in an embodiment of the present invention; Figure 7It is a schematic structural diagram of an electronic fuse disclosed in an embodiment of the present invention. Detailed implementation manners

[0018] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

[0019] The terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or terminal that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or terminals.

[0020] Referring to "embodiment" herein means that a specific feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0021] The present invention discloses a safety protection circuit and an electronic fuse for both AC and DC use, which can monitor the line current of the safety protection circuit in real time, improving the timeliness of line current monitoring; when the line current exceeds the safety control conditions, it can quickly generate corresponding safety drive signals, thereby driving the safety protection module to perform safety control operations, improving the response speed to abnormal situations in the safety protection circuit; through the coordinated work of the monitoring and driving module and the safety protection module, effective monitoring and safety supervision of the line current are achieved, significantly enhancing the use safety and reliability of the safety protection circuit. The following will be described in detail respectively.

[0022] Embodiment 1 Please refer to Figure 1 , Figure 1 It is a schematic structural diagram of a safety protection circuit for both AC and DC use disclosed in an embodiment of the present invention. Among them, Figure 1 The described safety protection circuit for both AC and DC use can be applied to an electronic fuse, and the embodiments of the present invention do not make limitations. AsFigure 1 As shown, the AC / DC dual-purpose safety protection circuit may include a monitoring and driving module 10 and a safety protection module 20, where: The first ends of the monitoring and driving module 10 and the safety protection module 20 are both used to connect to the positive pole of the power supply; the second end of the monitoring and driving module 10 is electrically connected to the second end of the safety protection module 20; the third end of the safety protection module 20 is used to connect to the negative pole of the power supply; The monitoring and driving module 10 is used to monitor the line current of the safety protection circuit; and when it is determined that the line current meets the preset safety control conditions, generate a safety driving signal corresponding to the line current; The safety protection module 20 is used to, after receiving the safety driving signal, perform a safety control operation according to the safety driving signal, and the safety control operation is used to cut off the connection circuit between the safety protection circuit and the power supply.

[0023] It can be seen that implementing Figure 1 the described AC / DC dual-purpose safety protection circuit can monitor the line current of the safety protection circuit in real time, improving the timeliness of line current monitoring; when the line current exceeds the safety control conditions, it can quickly generate a corresponding safety driving signal, thereby driving the safety protection module to perform a safety control operation, improving the response speed to abnormal situations in the safety protection circuit; through the collaborative work of the monitoring and driving module and the safety protection module, effective monitoring and safety supervision of the line current are realized, significantly enhancing the use safety and reliability of the safety protection circuit.

[0024] In an optional embodiment, the monitoring and driving module 10 includes a monitoring sub-module 101 and a driving sub-module 102, where: The first ends of the monitoring sub-module 101 and the driving sub-module 102 are both used to connect to the positive pole of the power supply; the second ends of the monitoring sub-module 101 and the driving sub-module 102 are both electrically connected to the second end of the safety protection module 20; The monitoring sub-module 101 is used to monitor the line current of the safety protection circuit; and transmit the current information of the line current to the driving sub-module 102; the current information is used to indicate the current state of the line current, and the current state includes a normal state or an abnormal state, and the abnormal state includes overload or short circuit; The driving sub-module 102 is used to generate a safety driving signal corresponding to the current information when the current information indicates that the preset safety control conditions are met; Among them, the current information indicating that the preset safety control conditions are met specifically includes that the current information indicates that there is overload or short circuit in the line current.

[0025] It can be seen that in this alternative embodiment, by subdividing the monitoring and driving module into a monitoring sub-module and a driving sub-module, refined monitoring and conditional driving of the line current of the safety protection circuit are achieved. Specifically, the monitoring sub-module can accurately capture the current state of the line current in the safety protection circuit, including normal and abnormal (such as overload and short circuit), and transmit the real-time current information to the driving sub-module. The driving sub-module then makes an intelligent judgment based on the preset safety control conditions, and quickly generates a corresponding safety driving signal after determining that the safety control conditions are met, so as to immediately trigger a safety protection operation when an abnormal current is detected. Through this solution, not only the accuracy and response speed of current monitoring are improved, but also the efficient and stable operation of the safety protection circuit under complex working conditions is ensured, further enhancing the safety and reliability of the circuit.

[0026] In another alternative embodiment, please refer to Figure 3 , Figure 3 which is a schematic structural diagram of another AC / DC dual-use safety protection circuit disclosed in the embodiment of the present invention. As Figure 3 shown, the monitoring sub-module 101 may include a voltage sampling resistor R1, a filter capacitor C1, a voltage stabilizing resistor R2, and a first voltage stabilizing diode D1, where: The first end of the voltage sampling resistor R1, the first end of the filter capacitor C1, and the positive electrode of the first voltage stabilizing diode D1 are all used to connect to the positive electrode of the power supply; the negative electrode of the first voltage stabilizing diode is electrically connected to the first end of the voltage stabilizing resistor R2; the second end of the voltage sampling resistor R1, the second end of the filter capacitor C1, and the second end of the voltage stabilizing resistor R2 are all electrically connected to the second end of the safety protection module 20; The voltage sampling resistor R1 is used to monitor the line current of the safety protection circuit; The filter capacitor C1 is used to perform filtering on the input voltage of the power supply to eliminate extremely narrow pulses existing in the safety protection circuit; The first voltage stabilizing diode D1 is used to perform rectification and / or voltage stabilization on the input voltage; The voltage stabilizing resistor R2 is used to perform current limiting and voltage division on the input voltage.

[0027] In this alternative embodiment, the positive electrode of the power supply corresponds to Figure 3 the DC incoming line in Figure 3 ; the negative electrode of the power supply corresponds to Figure 4 , Figure 5 and Figure 6 the DC outgoing line in. It should be noted that the DC incoming lines in subsequent

[0028] It can be seen that in this alternative embodiment, a high-performance monitoring sub-module is constructed by introducing a voltage sampling resistor, a filter capacitor, a voltage stabilizing resistor, and a first voltage stabilizing diode. Specifically: the voltage sampling resistor can accurately monitor the line current to ensure the timeliness and accuracy of current monitoring; the filter capacitor can effectively eliminate extremely narrow pulses in the input voltage to improve the circuit stability; the first voltage stabilizing diode can achieve rectification and voltage stabilization functions to ensure the reliable operation of the monitoring sub-module within a wide voltage range; the voltage stabilizing resistor provides current limiting and voltage division processing to protect the subsequent circuit from high voltage impact; through the sub-components of the monitoring sub-module, not only the anti-interference ability and working stability of the monitoring sub-module are enhanced, but also the overall performance and safety of the safety protection circuit are improved.

[0029] In another alternative embodiment, as Figure 2 and Figure 3 shown, the drive sub-module 102 includes a resonant unit LRC and a target triode Q1, and the safety protection module 20 includes a voltage stabilizing sub-module 201, a control sub-module 202, and a protection sub-module 203, where: The first end of the resonant unit LRC is used to connect to the positive pole of the power supply; the second end of the voltage sampling resistor R1 and the second end of the resonant unit LRC are both electrically connected to the first end of the protection sub-module 203; the third end of the resonant unit LRC is electrically connected to the base of the target triode Q1; the fourth end of the resonant unit LRC and the collector of the target triode Q1 are both electrically connected to the first end of the voltage stabilizing sub-module 201; The emitter of the target triode Q1 and the first end of the control sub-module 202 are both electrically connected to the second end of the protection sub-module 203; the second end of the control sub-module 202 is electrically connected to the second end of the voltage stabilizing sub-module 201; the third end of the voltage stabilizing sub-module 201 is electrically connected to the third end of the protection sub-module 203.

[0030] In this alternative embodiment, please refer to Figure 3 , the resonant unit LRC may specifically include a resonant capacitor C4, a resonant resistor R5, and a resonant inductor L1; where the resonant inductor L1 corresponds to the primary inductor of the transformer T1. And, the resonant unit LRC is used to adjust the oscillation frequency of the safety protection circuit.

[0031] The target triode Q1 is used to perform state switching according to the line current fed back by the voltage sampling resistor R1 and generate a target signal for the protection sub-module 203 according to the corresponding state switching result; the state switching is used to switch the target triode Q1 between the on state and the off state; the target signal includes a drive signal corresponding to the on state or a cut-off signal corresponding to the off state.

[0032] The voltage stabilizing sub-module 201 is used to perform voltage stabilization processing on the current flowing through the voltage stabilizing sub-module 201.

[0033] The control sub-module 202 is used to adjust the maintenance working time of the protection sub-module 203.

[0034] The protection sub-module 203 is used to switch the protection sub-module 203 from the on-state to the off-state according to the drive signal when the target triode Q1 switches to the on-state.

[0035] The protection sub-module 203 is further used to switch the protection sub-module 203 from the off-state to the on-state according to the cut-off signal when the target triode Q1 switches to the cut-off state.

[0036] It can be seen that in this optional embodiment, through the integration of the resonant unit, the target triode and the multi-functional safety protection module, high-precision control and fast response of the safety protection circuit are achieved. Specifically: the resonant unit can adjust the circuit oscillation frequency and optimize the circuit performance; the target triode can switch states in real time according to the line current and synchronously and accurately generate drive or cut-off signals, realizing the intelligent control of the safety protection circuit; the voltage stabilization sub-module can ensure the stability of the circuit voltage and improve the reliability of the safety protection circuit; the control sub-module can flexibly adjust the maintenance working time of the protection module, which is beneficial to enhancing the adaptability and practicability of the safety protection circuit; the protection sub-module can quickly switch between the on-state and the off-state according to the signal of the target triode, accurately and quickly realizing the overload and short-circuit protection of the circuit; through the sub-modules / components of the drive sub-module and the safety protection module, not only the response speed and protection accuracy of the safety protection circuit are improved, but also the stable operation of the circuit under various working conditions is ensured, further improving the overall safety performance of the safety protection circuit.

[0037] In another optional embodiment, as Figure 3 and Figure 4 shown, the target triode Q1 is a PNP type triode or an NPN type triode; and as Figure 3 shown, when the target triode Q1 is a PNP type triode, the voltage stabilization sub-module 201 includes a second voltage stabilizing diode D2; the control sub-module 202 includes a first control capacitor C2, where: The collector of the target triode Q1 is electrically connected to the negative electrode of the second voltage stabilizing diode D2; the positive electrode of the second voltage stabilizing diode D2 is respectively electrically connected to the third terminal of the protection sub-module 203 and the negative electrode of the control capacitor; the emitter of the target triode Q1 and the positive electrode of the first control capacitor C2 are both used to connect to the positive electrode of the power supply.

[0038] In this optional embodiment, optionally, as Figure 4 shown, when the target triode Q1 is an NPN type triode, the voltage stabilization sub-module 201 includes a third voltage stabilizing diode D3; the control sub-module 202 includes a second control capacitor C3, where: The collector of the target triode Q1 is electrically connected to the positive electrode of the third voltage stabilizing diode D3; the negative electrode of the third voltage stabilizing diode D2 is respectively electrically connected to the third terminal of the protection sub-module 203 and the positive electrode of the control capacitor; the emitter of the target triode Q1 and the negative electrode of the second control capacitor C3 are both used to connect to the positive electrode of the power supply.

[0039] In this optional embodiment, when the target triode Q1 is a PNP type triode, a germanium PNP type triode ( Figure 3 is the germanium PNP type triode in Figure 4 can be specifically selected); when the target triode Q1 is an NPN type triode, a silicon NPN type triode (

[0040] is the silicon NPN type triode in

[0041] can be specifically selected); among them, for triodes of different models, corresponding adapted components and device connection relationships are provided, that is, the above-mentioned second voltage stabilizing diode D2, third voltage stabilizing diode D3, and first control capacitor C2, second control capacitor C3, which can flexibly and precisely adjust their connection relationships with the triode, while ensuring the operation stability of the safety protection circuit, improving the configuration flexibility of the safety protection circuit. Figure 5 , Figure 5 is a schematic structural diagram of another AC / DC dual-use safety protection circuit disclosed in the embodiment of the present invention; as Figure 3 , Figure 4 and Figure 5 shown, the protection sub-module 203 includes a first relay K1 or a second relay K2; as Figure 3 and Figure 4 shown, the first relay K1 in includes an alarm output function, and the second relay K2 does not include an alarm output function;

[0042] The protection sub-module 203 is further configured to output an alarm signal corresponding to the line current when the protection sub-module 203 is the first relay K1 and when the target triode Q1 switches to the on state, so as to prompt that there is current overload or current short circuit in the safety protection circuit.In this alternative embodiment, the first relay K1 and the second relay K2 can be selected as appropriate low operating voltage magnetic latching relays or conventional ordinary relays according to actual usage requirements, ensuring that they can withstand the expected maximum current and operate quickly. Further, the first relay K1 is of the double-pole double-throw type, where one set of contacts is used to conduct current and the other is used for alarm signal output. Specifically, for the specific structures of these two types of relays, please refer to Figure 3 , Figure 4 and Figure 5 , where Figure 3 and Figure 4 adopt the first relay K1; Figure 5 adopt the relay K2.

[0043] In this alternative embodiment, the normally closed contacts of the first relay K1 are 9 and 10, 3 and 4. When the current in the circuit does not exceed the set threshold, the first relay K1 does not operate, that is, contact 9 attracts contact 10, and contact 3 attracts contact 4. When the current in the safety protection circuit exceeds the set threshold, the first relay K1 operates, contact 9 attracts contact 8, and contact 4 attracts contact 5, thereby disconnecting the power supply current of the safety protection circuit from the power supply.

[0044] In this alternative embodiment, when the current in the circuit does not exceed the set threshold, Figure 5 the second relay K2 in

[0045] does not operate, that is, contact 3 attracts contact 5. When the current in the safety protection circuit exceeds the set threshold, the second relay K2 operates, and contact 3 attracts contact 2, thereby disconnecting the power supply current of the safety protection circuit from the power supply.

[0046] It should be noted that when manual reset is not required, an ordinary relay can be selected for this relay; when an alarm signal output is not required, a single-pole double-throw relay can be selected to reduce volume and cost. At the same time, the selected relays must all be fast relays.

[0047] In yet another alternative embodiment, the first relay K1 or the second relay K2 may further be provided with a reset button for performing reset control on the first relay K1 or the second relay K2. Specifically, when the user presses the reset button, the relay contacts can be re-closed in a currentless state.

[0048] It should be noted that the reset button can be directly configured on the first relay K1 or the second relay K2, or can be an external button connected to the first relay K1 or the second relay K2. The setting of the reset button can be adjusted according to needs and is not limited in the embodiments of the present invention.

[0049] In this alternative embodiment, it should be noted that the overall safety protection circuit utilizes the combination of an RLC multivibrator circuit (corresponding to the above-mentioned monitoring and driving module) and a low operating voltage magnetic latching relay (such as 2 - 3 volts) (corresponding to the above-mentioned safety protection module) to achieve a circuit protection function without external voltage and grounding, thereby significantly improving the reliability and application flexibility of circuit protection.

[0050] Furthermore, this AC / DC dual-use safety protection circuit, different from existing electronic fuses, uses PMOS or NMOS as switching devices. Due to production process limitations, PMOS or NMOS switching transistors can only operate within a specific voltage range, with poor versatility. Based on the above-mentioned subdivided circuit structure of the AC / DC dual-use safety protection circuit, technical effects such as AC / DC universality, a wide operating voltage range, and a large dynamic range can be achieved; at the same time, this safety protection circuit can be serially connected to the positive or negative pole (in a DC system), overcoming the defect that existing electronic fuses must be powered by a protection system and solving the problem of electronic fuse failure when the power supply system deviates from the operating voltage.

[0051] In this alternative embodiment, the circuit for detection and control in the safety protection circuit can achieve "floating ground" operation, without being restricted by the operating voltage and operating current; at the same time, a relay is used as the contact, and the on-resistance is very small and can be ignored in most cases. This design enables the safety protection circuit to adapt to application scenarios with large currents and high voltages.

[0052] In this alternative embodiment, the current and voltage that existing electronic fuses can withstand are limited, otherwise the fuses themselves may be damaged. This solution uses a Joule thief circuit, and as long as 0.04 volts is reached on the detection resistor (the above-mentioned voltage sampling resistor), the relay can be driven to work. Its voltage drop is small and the loss is small.

[0053] In this alternative embodiment, existing electronic fuses all use low-power switching transistors as outputs, with limitations on current polarity and magnitude. In this solution, a non-polar warning signal output can be achieved, and the contact current is large.

[0054] In this alternative embodiment, through the design of the safety protection circuit, it can resume operation on its own after troubleshooting, eliminating the trouble of replacing the fuse, and realizing the function of self - recovery (optional) or manual - intervention recovery.

[0055] In this alternative embodiment, the safety protection circuit is simple and has extremely strong anti - interference ability. It has "immunity" to common EMI interference; thus, compared with similar products, the cost of this solution is lower. Existing electronic fuses are relatively expensive and are mainly used in high - price products such as automobiles.

[0056] In another alternative embodiment, please refer to Figure 6 , Figure 6 is a schematic structural diagram of another AC - DC dual - use safety protection circuit disclosed in the embodiment of the present invention; as Figure 6 shown, the protection sub - module 203 includes a target MOS transistor Q2, a current - limiting resistor R3, and a voltage - dividing resistor R4, where: The source of the target MOS transistor Q2 is used to connect to the positive pole of the power supply; the gate of the target MOS transistor Q2 is electrically connected to the first end of the current - limiting resistor R3 and the first end of the voltage - dividing resistor R4 respectively; the drain of the target MOS transistor Q2 is electrically connected to the first end of the voltage - sampling resistor R1, the first end of the voltage - stabilizing resistor R2, and the first end of the resonance unit LRC respectively; The second end of the current - limiting resistor R3 is used to connect to the ground; the second end of the voltage - dividing resistor R4 is used to connect to the negative pole of the power supply; The target MOS transistor Q2 is used to switch the target MOS transistor Q2 from the conducting state to the cut - off state according to the drive signal when the target triode Q1 switches to the conducting state; and is also used to switch the target MOS transistor Q2 from the cut - off state to the conducting state according to the drive signal when the target triode Q1 switches to the cut - off state; The current - limiting resistor R3 is used to perform current - limiting operation on the current flowing through the target MOS transistor Q2 to protect the target MOS transistor Q2; The voltage - dividing resistor R4 is used to perform voltage - dividing operation on the current flowing through the target MOS transistor Q2 and is also used to control the on - off of the target MOS transistor Q2.

[0057] In this alternative embodiment, specifically, the target MOS transistor Q2 can be a PMOS transistor.

[0058] It can be seen that in this alternative embodiment, a PMOS transistor control different from relay control is provided. The replacement of this component enables the safety protection circuit to adapt to scenarios with microsecond-level responses. Specifically: by introducing a protection sub-module composed of a target MOS transistor, a current-limiting resistor, and a voltage-dividing resistor, high-precision control and reliable protection of the safety protection circuit are achieved. Among them, the target MOS transistor can accurately control the on / off of the circuit according to the state switching signal of the target triode, and this target MOS transistor can adapt to the scenarios and requirements of microsecond-level responses and can effectively respond to current overload or short-circuit situations. The current-limiting resistor can effectively limit the current flowing through the target MOS transistor, prevent it from being damaged by overheating, and enhance the overall safety of the safety protection circuit. The voltage-dividing resistor can not only provide the necessary voltage-dividing function but also participate in controlling the on / off logic of the target MOS transistor, which is beneficial to improving the operating stability of the safety protection circuit. Through this solution, not only the response speed and protection accuracy of the safety protection circuit are improved, but also the reliability and durability of the circuit are significantly enhanced.

[0059] The working principle of the AC / DC dual-use safety protection circuit in the embodiment of the present invention is as follows: In the embodiment of the present invention, after the safety protection circuit is normally connected to the supply voltage of the power supply, it can monitor the line current of the safety protection circuit in real time through the monitoring and driving module, specifically including monitoring the magnitude and current change of the line current. At the same time, based on the set safety control conditions, the magnitude of this current is executed, and when it is determined that the line current meets the safety control conditions, a corresponding safety driving signal can be quickly generated, and based on this safety driving signal, the safety protection is controlled to perform safety control operations, thereby switching the path of the overall safety protection circuit and the power supply, that is, realizing fast and accurate power-off protection for abnormal current in the safety protection circuit.

[0060] Embodiment 2 Please refer to Figure 7 , Figure 7 which is a schematic structural diagram of an electronic fuse disclosed in the embodiment of the present invention. Among them, Figure 7 the described electronic fuse can be applied to devices / apparatus that require circuit safety monitoring, such as power cable monitoring devices, transmission line monitoring devices, etc., which are not limited in the embodiment of the present invention. As Figure 7 shown, the electronic fuse can include the AC / DC dual-use safety protection circuit disclosed in Embodiment 1 of the present invention. It should be noted that for a detailed description of the electronic fuse, please refer to the specific description of the relevant content in Embodiment 1, which will not be repeated in this embodiment.

[0061] It can be seen that in the implementation Figure 7The described electronic fuse can monitor the line current of the safety protection circuit in real time, improving the timeliness of line current monitoring; when the line current exceeds the safety control conditions, it can quickly generate corresponding safety drive signals, thereby driving the safety protection module to perform safety control operations, improving the response speed to abnormal situations in the safety protection circuit; through the coordinated work of the monitoring and driving module and the safety protection module, effective monitoring and safety supervision of the line current are achieved, significantly enhancing the use safety and reliability of the safety protection circuit.

[0062] The above has introduced in detail a safety protection circuit and an electronic fuse for both AC and DC applications disclosed in the embodiments of the present invention. Specific embodiments are used herein to elaborate on the principles and implementation manners of the present invention. However, the above preferred embodiments are not intended to limit the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, based on the idea of the present invention, changes will occur in the specific implementation manners and application scopes without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be defined by the scope of the claims.

Claims

1. A safety protection circuit for AC and DC, characterized in that: The safety protection circuit includes a monitoring and driving module and a safety protection module, wherein: The first end of the monitoring and driving module and the first end of the safety protection module are both used to connect to the positive pole of the power supply; the second end of the monitoring and driving module is electrically connected to the second end of the safety protection module; the third end of the safety protection module is used to connect to the negative pole of the power supply; The monitoring and driving module is used to monitor the line current of the safety protection circuit; and when it is determined that the line current meets the preset safety control condition, generate a safety driving signal corresponding to the line current; The safety protection module is used to perform a safety control operation according to the safety drive signal after receiving the safety drive signal, and the safety control operation is used to cut off the connection circuit between the safety protection circuit and the power supply.

2. The AC / DC dual-purpose safety protection circuit according to claim 1, characterized in that: The monitoring and driving module includes a monitoring submodule and a driving submodule, wherein: The first end of the monitoring submodule and the first end of the driving submodule are both used to connect to the positive pole of the power supply; the second end of the monitoring submodule and the second end of the driving submodule are both electrically connected to the second end of the safety protection module; The monitoring submodule is used to monitor the line current of the safety protection circuit; and transmit the current information of the line current to the driving submodule; the current information is used to indicate the current state of the line current, and the current state includes a normal state or an abnormal state, and the abnormal state includes an overload or a short circuit; The driving submodule is used to generate a safety driving signal corresponding to the current information when the current information indicates that a preset safety control condition is met; The current information indicating that the preset safety control condition is satisfied specifically includes that the current information indicates that the line current has the overload or the short circuit.

3. The AC / DC dual-purpose safety protection circuit according to claim 2, characterized in that: The monitoring submodule includes a voltage sampling resistor, a filter capacitor, a voltage stabilizing resistor and a first voltage stabilizing diode, wherein: The first end of the voltage sampling resistor, the first end of the filter capacitor, and the positive electrode of the first voltage stabilizing diode are all used to connect to the positive electrode of the power supply; the negative electrode of the first voltage stabilizing diode is electrically connected to the first end of the voltage stabilizing resistor; the second end of the voltage sampling resistor, the second end of the filter capacitor, and the second end of the voltage stabilizing resistor are all electrically connected to the second end of the safety protection module; The voltage sampling resistor is used to monitor the line current of the safety protection circuit; The filter capacitor is used to filter the input voltage of the power supply to eliminate the extremely narrow pulses existing in the safety protection circuit; The first voltage stabilizing diode is used to perform rectification and / or voltage stabilization processing on the input voltage; The voltage-stabilizing resistor is used to perform current limiting and voltage division processing on the input voltage.

4. The AC / DC dual-purpose safety protection circuit according to claim 3, characterized in that: The driving submodule includes a resonance unit and a target transistor, and the safety protection module includes a voltage stabilization submodule, a control submodule and a protection submodule, wherein: The first end of the resonance unit is used to connect the positive electrode of the power supply; the second end of the voltage sampling resistor and the second end of the resonance unit are both electrically connected to the first end of the protection submodule; the third end of the resonance unit is electrically connected to the base of the target transistor; the fourth end of the resonance unit and the collector of the target transistor are both electrically connected to the first end of the voltage stabilization submodule; The emitter of the target transistor and the first end of the control submodule are electrically connected to the second end of the protection submodule; the second end of the control submodule is electrically connected to the second end of the voltage stabilizing submodule; and the third end of the voltage stabilizing submodule is electrically connected to the third end of the protection submodule.

5. The AC / DC dual-purpose safety protection circuit according to claim 4, characterized in that: The resonance unit is used to adjust the oscillation frequency of the safety protection circuit; The target transistor is used to perform state switching according to the line current fed back by the voltage sampling resistor, and generate a target signal for the protection submodule according to the corresponding state switching result; the state switching is used to switch the target transistor between an on state and an off state; the target signal includes a drive signal corresponding to the on state or an off signal corresponding to the off state; The voltage stabilizing submodule is used to perform voltage stabilization processing on the current flowing through the voltage stabilizing submodule; The control submodule is used to adjust the maintenance working time of the protection submodule; The protection submodule is used to switch the protection submodule from the on state to the off state according to the driving signal when the target transistor is switched to the on state; The protection submodule is further configured to switch the protection submodule from the disconnected state to the connected state according to the cutoff signal when the target transistor is switched to the cutoff state.

6. The AC / DC dual-purpose safety protection circuit according to claim 4, characterized in that: The target transistor is a PNP transistor or an NPN transistor; and when the target transistor is a PNP transistor, the voltage stabilizing submodule includes a second voltage stabilizing diode; the control submodule includes a first control capacitor, wherein: The collector of the target transistor is electrically connected to the cathode of the second voltage-stabilizing diode; the anode of the second voltage-stabilizing diode is electrically connected to the third end of the protection submodule and the cathode of the control capacitor respectively; the emitter of the target transistor and the anode of the first control capacitor are both used to connect to the anode of the power supply.

7. The AC / DC dual-purpose safety protection circuit according to claim 4, characterized in that: When the target transistor is an NPN transistor, the voltage stabilizing submodule includes a third voltage stabilizing diode; the control submodule includes a second control capacitor, wherein: The collector of the target transistor is electrically connected to the anode of the third zener diode; the cathode of the third zener diode is electrically connected to the third end of the protection submodule and the anode of the control capacitor respectively; the emitter of the target transistor and the cathode of the second control capacitor are both used to connect to the anode of the power supply.

8. The AC / DC dual-purpose safety protection circuit according to claim 5, characterized in that: The protection submodule includes a first relay or a second relay; the first relay includes an alarm output function, and the second relay does not include the alarm output function; The protection submodule is also used to output an alarm signal corresponding to the line current when the protection submodule is the first relay and when the target transistor is switched to the on state, so as to prompt that the safety protection circuit has a current overload or a current short circuit.

9. The AC / DC dual-purpose safety protection circuit according to claim 5, characterized in that: The protection submodule includes a target MOS tube, a current limiting resistor and a voltage dividing resistor, wherein: The source of the target MOS tube is used to connect the positive electrode of the power supply; the gate of the target MOS tube is electrically connected to the first end of the current limiting resistor and the first end of the voltage dividing resistor respectively; the drain of the target MOS tube is electrically connected to the first end of the voltage sampling resistor, the first end of the voltage stabilizing resistor, and the first end of the resonance unit respectively; The second end of the current limiting resistor is used for grounding; the second end of the voltage dividing resistor is used for connecting the negative electrode of the power supply; The target MOS tube is used to switch the target MOS tube from the on state to the off state according to the driving signal when the target triode is switched to the on state; and is also used to switch the target MOS tube from the off state to the on state according to the driving signal when the target triode is switched to the off state; The current limiting resistor is used to perform a current limiting operation on the current flowing through the target MOS tube to protect the target MOS tube; The voltage-dividing resistor is used to perform a voltage-dividing operation on the current flowing through the target MOS tube, and is also used to control the on-off of the target MOS tube.

10. An electronic fuse, characterized in that: The electronic fuse comprises a device body, and the electronic fuse comprises an AC / DC dual-purpose safety protection circuit as described in any one of claims 1 to 9.

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