Lightning surge protection circuit and power supply
By controlling the conduction and closing of the switching device, the energy-consuming circuit absorbs residual energy, solving the problem that the existing technology cannot fully absorb lightning surge energy, and achieving the effect of reducing the electrical stress of the subsequent circuit and improving the circuit's lightning surge resistance.
Patent Information
- Application Number
- CN202421408370.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-19
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-06-19
AI Technical Summary
When the prior art prevents the damage of lightning surges to the circuit, it cannot fully absorb instantaneous high-energy lightning surge voltage and current, resulting in a sudden increase in the electrical stress of the subsequent circuit, which may cause the power supply to fail.
By controlling the conduction and closing of the switching device, the energy-consuming circuit absorbs residual energy, thereby reducing the electrical stress of the subsequent circuit and improving the circuit's lightning surge resistance.
It effectively reduces the electrical stress of the later-stage circuit, improves the circuit's resistance to lightning surges, and prevents power supply failure.
Smart Images
Figure CN222802534U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of electronic technology, in particular to a lightning surge protection circuit and a power supply. Background Art
[0002] Lightning surge is a transient high voltage or high current phenomenon caused by lightning or electronic and electrical switching. Lightning surge can cause overvoltage and overcurrent in the circuit, and its energy can burn out the components on the circuit in an instant.
[0003] In order to prevent lightning surges from damaging subsequent circuits, some electronic devices use surge protection circuits or surge protection components. For example, a power factor correction (PFC) circuit is used to absorb the energy generated by lightning surges. However, the energy absorbed by the PFC circuit will cause the voltage of the electrolytic capacitor to increase, resulting in a significant increase in the voltage and current stress of the PFC circuit and subsequent circuits. If there are multiple lightning strikes, the power supply will explode and fail. Therefore, relevant protection measures are needed.
[0004] At present, the solution to this problem is usually to add a protection circuit at the front end of the power supply. The simplest method is to connect a varistor, a discharge tube, etc. in parallel at the input end. However, these protection circuits cannot completely absorb the lightning surge voltage and current with instantaneous high energy. Some of the energy will be transmitted to the lower circuit, causing the electrical stress of the lower circuit to suddenly increase. If it exceeds the range, it will cause the power supply to fail. Utility Model Content
[0005] In order to overcome the above-mentioned deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a lightning surge protection circuit and a power supply, which can control the conduction and closing of the switching device to enable the energy consumption circuit to absorb the remaining energy, thereby reducing the electrical stress of the subsequent circuit and improving the circuit's ability to resist lightning surges.
[0006] The utility model provides a lightning surge protection circuit, characterized in that the lightning surge protection circuit includes an energy consumption circuit and a control component connected to a power factor correction circuit; the power factor correction circuit includes a first switch device and an electrolytic capacitor respectively connected between a positive power transmission line and a negative power transmission line; the energy consumption circuit includes an energy consumption device and a second switch device connected in series between the positive power transmission line and the negative power transmission line; the control component is connected to the control end of the second switch device, and the control component is used to disconnect the first switch device when it is detected that the voltage of the subsequent circuit connected to the positive power transmission line and the negative power transmission line exceeds a first set threshold value; and connect the second switch device when it is detected that the voltage at the two electrodes of the electrolytic capacitor exceeds a second set threshold value.
[0007] In a possible implementation, the power factor correction circuit also includes a voltage controller; the control component is connected to the voltage controller; the voltage controller is used to periodically turn on and off the first switching device at a set frequency when the control component detects that the voltage of the electrolytic capacitor does not exceed the second set threshold.
[0008] In a possible implementation manner, the voltage controller is further configured to disconnect the first switching device when it is detected that the voltage of a subsequent circuit connected to the positive power transmission line and the negative power transmission line exceeds the first set threshold.
[0009] In a possible implementation, the control component further includes a voltage detection circuit, a detection end of the voltage detection circuit is connected between the positive power transmission line and the negative power transmission line, an output end of the voltage detection circuit is connected to the second switch device, and the voltage detection circuit is used to turn on the second switch device when it is detected that the voltage across the electrolytic capacitor exceeds the first set threshold; the voltage detection circuit is also used to turn off the second switch device when it is detected that the voltage across the electrolytic capacitor does not exceed the second set threshold.
[0010] In a possible implementation, the voltage detection circuit includes a detection component, a first resistor and a second resistor, the first resistor and the second resistor are connected in series between a positive power transmission line and a negative power transmission line, the first detection end of the detection component is connected to the negative power transmission line, the second detection end of the detection component is connected between the first resistor and the second resistor, and the output end of the detection component is the output end of the voltage detection circuit.
[0011] In a possible implementation manner, the resistance value of the first resistor is greater than the resistance value of the second resistor.
[0012] In a possible implementation, the energy consumption component includes a wire-wound resistor.
[0013] In a possible implementation manner, the energy consumption circuit further includes a diode connected in parallel with the energy consumption device, and an anode of the diode is connected to the positive power transmission line.
[0014] In some possible implementations, the power factor correction circuit further includes an inductor.
[0015] Another aspect of the present invention provides a power supply, comprising the aforementioned lightning surge protection circuit.
[0016] Compared with the prior art, the utility model has the following beneficial effects:
[0017] The utility model provides a lightning surge protection circuit and power supply, which control the on and off of a switch device to enable an energy consumption circuit to absorb residual energy, thereby reducing the electrical stress of a subsequent circuit and improving the circuit's lightning surge resistance. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.
[0019] Figure 1 One of the schematic diagrams of the lightning surge protection circuit provided in this embodiment;
[0020] Figure 2 A schematic diagram of a lightning surge protection circuit and front-end and back-end circuits provided in this embodiment;
[0021] Figure 3 The second schematic diagram of the lightning surge protection circuit provided in this embodiment;
[0022] Figure 4 The third schematic diagram of the lightning surge protection circuit provided in this embodiment;
[0023] Figure 5 The fourth schematic diagram of the lightning surge protection circuit provided in this embodiment;
[0024] Figure 6 The fifth schematic diagram of the lightning surge protection circuit provided in this embodiment;
[0025] Figure 7 This is the sixth schematic diagram of the lightning surge protection circuit provided in this embodiment.
[0026] Icons: 10-power factor correction circuit; 20-energy consumption circuit; 30-control component; 40-voltage controller; 21-energy consumption device; 31-sampler; L1-inductor; C1-electrolytic capacitor; Q1-first switching device; Q2-second switching device; Vpfc-detection component; Vbus+-positive power transmission line; Vbus--negative power transmission line; R1-first resistor; R2-second resistor; D1-diode; R3-winding resistor. DETAILED DESCRIPTION
[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0028] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0029] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0030] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0031] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0032] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0033] The specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings.
[0034] Please refer to Figure 1 The present application provides a lightning surge protection circuit, which can be used to protect against lightning surges generated between a positive power transmission line Vbus+ and a negative power transmission line Vbus-.
[0035] Specifically, the lightning surge protection circuit includes an energy consumption circuit 20 and a control component 30 connected to the power factor correction circuit 10 .
[0036] The power factor correction circuit 10 includes a first switch device Q1 and an electrolytic capacitor C1 respectively connected between a positive power transmission line Vbus+ and a negative power transmission line Vbus-.
[0037] The energy consumption circuit 20 includes an energy consumption device 21 and a second switch device Q2 which are connected in series between a positive power transmission line Vbus+ and a negative power transmission line Vbus-.
[0038] The control component 30 is connected to the control end of the second switching device Q2. The control component 30 is used to disconnect the first switching device Q1 when it is detected that the voltage of the subsequent circuit connected to the positive power transmission line Vbus+ and the negative power transmission line Vbus- exceeds a first set threshold; and to connect the second switching device Q2 when it is detected that the voltage at the two poles of the electrolytic capacitor C1 exceeds a second set threshold.
[0039] For example, see Figure 2 The lightning surge front-stage circuit can be an EMC (Electromagnetic Compatibility) circuit, which can partially absorb the lightning surge voltage and current. This circuit further absorbs the residual lightning surge voltage and current; the lightning surge back-stage circuit includes various main power topology circuits.
[0040] Please refer again Figure 1 In this embodiment, after a lightning surge occurs, the electrolytic capacitor C1 absorbs the residual voltage and current thereof. At this time, the voltage across the electrolytic capacitor C1 is higher than the normal value. The control component 30 detects that the voltage value of the electrolytic capacitor C1 exceeds the second set threshold value, and controls the opening of the second switch device Q2. When the control component 30 detects that the voltage value of the subsequent main power topology circuit exceeds the first set threshold value, it first reduces the duty cycle and then drives the first switch device Q1 to close.
[0041] The second switch device Q2 is used to control the energy consumption circuit 20. After the second switch device Q2 is turned on, the energy on the electrolytic capacitor C1 is consumed by the energy consumption device 21 to reduce the voltage of the electrolytic capacitor C1. For example, during normal operation, the voltage of the power factor correction circuit 10 can be 400V. After the first switch device Q1 is turned off, the circuit will not boost the voltage, and the voltage on the electrolytic capacitor C1 will be further reduced to 310V. When there is no abnormality in the voltage on the electrolytic capacitor C1 and the subsequent circuit, the first switch device Q1 is turned on again, and the second switch device Q2 is turned off to perform power factor correction.
[0042] The first set threshold may be set to 400V, and the second set threshold may be set to 310V.
[0043] In some possible implementations, the power factor correction circuit 10 also includes a voltage controller 40; the control component 30 is connected to the voltage controller 40; the voltage controller 40 is used to periodically turn on and off the first switching device Q1 at a set frequency when the control component 30 detects that the voltage of the electrolytic capacitor C1 does not exceed the second set threshold.
[0044] In some possible implementations, the voltage controller 40 is further used to disconnect the first switching device Q1 when the control component 30 detects that the voltage of the subsequent circuit connected to the positive power transmission line Vbus+ and the negative power transmission line Vbus- exceeds a first set threshold.
[0045] For example, see Figure 3 In this embodiment, the voltage controller 40 is connected to the control component 30, and the voltage controller 40 is also connected to the first switch device Q1. The control component 30 includes a sampler 31, and the sampler 31 is used to periodically sample the voltage of the subsequent circuit connected to the positive power transmission line Vbus+ and the negative power transmission line Vbus- at a set frequency. When the voltage value exceeds its set threshold, the voltage controller 40 drives the first switch device Q1 to turn off; when the control component 30 detects that the voltage of the electrolytic capacitor C1 does not exceed the second set threshold for many times, the voltage controller 40 periodically turns on and off the first switch device Q1 at a set frequency. For example, after the voltage controller 40 receives the signal that the voltage of the electrolytic capacitor C1 does not exceed the second set threshold detected by the control component 30 for 15 times, it is set to send a square wave signal of a set frequency to the control end of the first switch device Q1 to control the first switch device Q1 to turn on or off at this frequency.
[0046] For some possible implementations, see Figure 4The control component 30 also includes a voltage detection circuit, the detection end of the voltage detection circuit is connected between the positive power transmission line Vbus+ and the negative power transmission line Vbus-, the output end of the voltage detection circuit is connected to the second switch device Q2, and the voltage detection circuit is used to turn on the second switch device Q2 when it is detected that the voltage across the electrolytic capacitor C1 exceeds the first set threshold value; the voltage detection circuit is also used to turn off the second switch device Q2 when it is detected that the voltage across the electrolytic capacitor C1 does not exceed the second set threshold value.
[0047] For some possible implementations, please refer again to Figure 4 The voltage detection circuit includes a detection component Vpfc, a first resistor R1 and a second resistor R2, the first resistor R1 and the second resistor R2 are connected in series between the positive power transmission line Vbus+ and the negative power transmission line Vbus-, the first detection end of the detection component Vpfc is connected to the negative power transmission line Vbus-, the second detection end of the detection component Vpfc is connected between the first resistor R1 and the second resistor R2, and the output end of the detection component is the output end of the voltage detection circuit.
[0048] For example, see Figure 4 In this embodiment, the voltage detected by the detection component Vpfc is the voltage of the second resistor R2. The voltage of the electrolytic capacitor C1 is too large. In order to prevent damage to the detection component Vpfc or cause safety problems, the voltage detection circuit is provided with a resistor. According to the different voltage divisions of the first resistor R1 and the second resistor R2, the voltage of the electrolytic capacitor C1 can be calculated in real time, thereby controlling the opening and closing of the second switch device Q2.
[0049] In some possible implementations, the resistance of the first resistor R1 is greater than the resistance of the second resistor R2.
[0050] For example, see Figure 4 In this embodiment, since the voltage across the electrolytic capacitor C1 is too large, the detection range of the detection component Vpfc is small. In order to ensure circuit safety and measure the voltage across the electrolytic capacitor C1, a resistor with a larger resistance is set as the first resistor R1, and a resistor with a smaller resistance is set as the second resistor R2. The first resistor R1 and the second resistor R2 are connected in series between the positive power transmission line Vbus+ and the negative power transmission line Vbus-.
[0051] In some possible implementations, the energy consumption device 21 includes a wire-wound resistor R3.
[0052] Please refer to Figure 5In this embodiment, after a lightning surge occurs, the electrolytic capacitor C1 absorbs the residual voltage and current thereof. At this time, the voltage across the electrolytic capacitor C1 is higher than the normal value. The control component 30 detects that the voltage value of the electrolytic capacitor C1 exceeds the second set threshold value, and controls the opening of the second switch device Q2; when the control component 30 detects that the voltage value of the subsequent main power topology circuit exceeds its set threshold value, it drives the first switch device Q1 to close; at this time, the energy consumption circuit 20 consumes the voltage on the electrolytic capacitor C1 through the energy consumption device 21. In this embodiment, the energy consumption device 21 uses a winding resistor R3.
[0053] In some possible implementations, the energy consumption circuit 20 further includes a diode D1 connected in parallel with the energy consumption device 21 , and an anode of the diode D1 is connected to the positive power transmission line Vbus+.
[0054] For example, see Figure 6 In this embodiment, the diode D1 is connected in parallel with the energy consumption device 21. The winding resistor R3 is selected as the energy consumption device 21 in this embodiment. The winding resistor R3 will have parasitic inductance when working, and then generate a reverse voltage. In order to consume this part of the voltage, the diode D1 connected in parallel with the winding resistor R3 is set in this embodiment, and the positive electrode of the diode D1 is connected to the positive power transmission line Vbus+.
[0055] For some possible implementations, see Figure 7 , the power factor correction circuit 10 also includes an inductor L1.
[0056] The present application example also provides a power supply, including the aforementioned lightning surge protection circuit, which controls the on and off of the switching device to enable the energy consumption circuit 20 to absorb the remaining energy, thereby reducing the electrical stress of the subsequent circuit and improving the power supply's ability to resist lightning surges.
[0057] In summary, the present application provides a lightning surge protection circuit and power supply, wherein the lightning surge protection circuit includes an energy consumption circuit 20 and a control component 30 connected to a power factor correction circuit 10; the power factor correction circuit 10 includes a first switch device Q1 and an electrolytic capacitor C1 respectively connected between a positive power transmission line Vbus+ and a negative power transmission line Vbus-; the energy consumption circuit 20 includes an energy consumption device and a second switch device Q2 connected in series between the positive power transmission line Vbus+ and the negative power transmission line Vbus-; the control component 30 is connected to the control end of the second switch device Q2, and the control component 30 is used to disconnect the first switch device Q1 when it is detected that the voltage of the subsequent circuit connected to the positive power transmission line Vbus+ and the negative power transmission line Vbus- exceeds a first set threshold; and when it is detected that the voltage of the two poles of the electrolytic capacitor C1 exceeds a second set threshold, the second switch device Q2 is turned on. This circuit enables the energy consumption circuit 20 to absorb the remaining energy by controlling the conduction and closing of the switch device, thereby reducing the electrical stress of the subsequent circuit and improving the circuit's lightning surge resistance.
[0058] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A lightning surge protection circuit, characterized in that: The lightning surge protection circuit includes an energy consumption circuit and a control component connected to a power factor correction circuit; The power factor correction circuit includes a first switch device and an electrolytic capacitor respectively connected between a positive power transmission line and a negative power transmission line; The energy consumption circuit includes an energy consumption device and a second switch device connected in series between the positive power transmission line and the negative power transmission line; The control component is connected to the control end of the second switch device, and the control component is used to disconnect the first switch device when it is detected that the voltage of the subsequent circuit connected to the positive power transmission line and the negative power transmission line exceeds a first set threshold; When it is detected that the voltage at the two electrodes of the electrolytic capacitor exceeds a second set threshold, the second switch device is turned on.
2. The lightning surge protection circuit according to claim 1, characterized in that: The power factor correction circuit also includes a voltage controller; the control component is connected to the voltage controller; The voltage controller is used to periodically turn on and off the first switch device at a set frequency when the control component detects that the voltage of the electrolytic capacitor does not exceed the second set threshold.
3. The lightning surge protection circuit according to claim 2, characterized in that: The voltage controller is further configured to disconnect the first switching device when detecting that the voltage of a subsequent circuit connected to the positive power transmission line and the negative power transmission line exceeds the first set threshold.
4. The lightning surge protection circuit according to claim 1, characterized in that: The control component also includes a voltage detection circuit, a detection end of the voltage detection circuit is connected between the positive power transmission line and the negative power transmission line, and an output end of the voltage detection circuit is connected to the second switch device. The voltage detection circuit is used to turn on the second switch device when it is detected that the voltage across the electrolytic capacitor exceeds the first set threshold value; the voltage detection circuit is also used to turn off the second switch device when it is detected that the voltage across the electrolytic capacitor does not exceed the second set threshold value.
5. The lightning surge protection circuit according to claim 4, characterized in that: The voltage detection circuit includes a detection component, a first resistor and a second resistor, the first resistor and the second resistor are connected in series between a positive power transmission line and a negative power transmission line, the first detection end of the detection component is connected to the negative power transmission line, the second detection end of the detection component is connected between the first resistor and the second resistor, and the output end of the detection component is the output end of the voltage detection circuit.
6. The lightning surge protection circuit according to claim 5, characterized in that: The resistance of the first resistor is greater than the resistance of the second resistor.
7. The lightning surge protection circuit according to claim 1, characterized in that: The energy consumption device includes a wire-wound resistor.
8. The lightning surge protection circuit according to claim 7, characterized in that: The energy consumption circuit further comprises a diode connected in parallel with the energy consumption device, wherein the anode of the diode is connected to the positive power transmission line.
9. The lightning surge protection circuit according to claim 1, characterized in that: The power factor correction circuit also includes an inductor.
10. A power supply, characterized in that: The invention comprises the lightning surge protection circuit as described in any one of claims 1 to 9.