Sequential release surge protector

Abstract

The present invention relates to a sequential release surge protector, comprising a wave head absorption channel, a wavelength pre-emission channel, and an energy release channel. The wave head absorption channel comprises a transient voltage suppression diode (TVS) and a first zinc oxide varistor (M0). The transient voltage suppression diode (TVS) is connected in series with the first zinc oxide varistor (M0), and the other end of the first zinc oxide varistor (M0) is grounded. A second zinc oxide varistor (M1) is connected in parallel to both ends of the transient voltage suppression diode (TVS). The second zinc oxide varistor (M1) and the first zinc oxide varistor (M0) form a wavelength pre-emission channel. The second zinc oxide varistor (M1) and the gas discharge tube (G) are connected in series with each other, and the other end of the gas discharge tube (G) is grounded. The second zinc oxide varistor (M1) and the gas discharge tube (G) form an energy release channel. This application targets the waveform characteristics of lightning currents and sequentially releases surge overcurrents to achieve the goals of higher continuous operating voltage, lower residual voltage, larger flow rate, and faster response time.

Description

Technical Field

[0001] The present invention relates to the technical field of lightning protection, in particular to a sequential release surge protector. Background Art

[0002] Currently, the nonlinear components used in surge protectors for power systems primarily include metal oxide varistors (MOVs), spark gaps, gas discharge tubes, and transient voltage suppressor (TVS) diodes. Under rated surge current conditions, high initial conduction voltages in existing MOVs result in high residual voltages. Low initial conduction voltages can reduce the MOV's operating life or even damage it due to power supply fluctuations and interference.

[0003] Current nonlinear devices are generally used alone or in simple parallel connections. To achieve the requirements of high initial conduction voltage, large flow rate, and low residual voltage, multi-level protection is used on the power line, and certain distance requirements must be met between each level. For power system protection in narrow or isolated areas (such as mobile base stations, regional automatic weather stations, high mountain or island radar stations, etc.), it is not possible to set up multi-level surge protectors. However, these places are generally areas with frequent lightning activity. How to set up a single surge protector device that can simultaneously meet the requirements of high initial conduction voltage, large flow rate, low residual voltage, and fast response time to achieve the effect of multi-level surge protection has become a problem that needs to be solved urgently. Summary of the Invention

[0004] In order to overcome the above-mentioned deficiencies of the prior art, the present invention proposes a sequential release surge protector to solve the technical problem that the existing surge protector varistor cannot achieve both high initial conduction voltage (stable operation) and low residual voltage (good protection effect) at the same time.

[0005] The present invention is achieved through the following technical solutions:

[0006] Sequential release surge protector, including wave head absorption channel, wavelength pre-emission channel and energy release channel,

[0007] The wave front absorption channel includes a transient voltage suppression diode TVS and a first zinc oxide varistor M0, wherein the transient voltage suppression diode TVS is connected in series with the first zinc oxide varistor M0, and the other end of the first zinc oxide varistor M0 is grounded;

[0008] A second zinc oxide varistor M1 is connected in parallel at both ends of the transient voltage suppression diode TVS, and the second zinc oxide varistor M1 and the first zinc oxide varistor M0 form a wavelength pre-emission channel;

[0009] The second zinc oxide varistor M1 is connected in series to a gas discharge tube G, the other end of the gas discharge tube G is grounded, and the second zinc oxide varistor M1 and the gas discharge tube G form an energy release channel.

[0010] Furthermore, the wave front absorption channel also includes a first voltage limiting resistor R1, and the first voltage limiting resistor R1 is connected in series with a transient voltage suppressor diode TVS.

[0011] Furthermore, the wavelength pre-transmission channel further includes a second voltage-limiting resistor R2 connected in series between the second zinc oxide varistor M1 and the first zinc oxide varistor M0.

[0012] Furthermore, the input end of the first zinc oxide varistor M0 is connected in series with an overheating fuse AUPO; the input end of the second zinc oxide varistor M1 is connected in series with an overheating fuse card K1.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The sequential release surge protector proposed in the present invention, based on the waveform characteristics of the lightning current, releases the surge overcurrent in sequence through the response time difference and flow capacity of the wave head absorption channel, wavelength pre-emission channel, and energy release channel, achieving the technical advantages of absorbing, consuming, and releasing part of the lightning current, and realizing the goals of higher continuous operating voltage, lower residual voltage, larger flow rate and fast response time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A circuit diagram of a sequential release surge protector according to an embodiment of the present invention;

[0016] Figure 2 This is a circuit diagram of the wave head absorption channel according to an embodiment of the present invention;

[0017] Figure 3 This is a circuit diagram of the wavelength pre-transmission channel according to an embodiment of the present invention;

[0018] Figure 4 A circuit diagram of the energy release channel according to an embodiment of the present invention;

[0019] Figure 5 This is a lightning waveform diagram according to an embodiment of the present invention. DETAILED DESCRIPTION

[0020] Examples are provided to illustrate certain embodiments of the present invention and should not be construed as limiting the scope of the present invention. The disclosed content of the present invention may be modified from materials, methods and reaction conditions simultaneously, and all such modifications should fall within the spirit and scope of the present invention.

[0021] At present, the commonly used lightning simulation waveforms are 8 / 20us, 10 / 350us, 2.6 / 50us, 1.2 / 50us, 10 / 700us, etc., which are composed of wave head T1, wavelength T2, and wave tail T. Figure 5 In view of the characteristics of lightning waveform and utilizing the characteristics of existing non-linear lightning protection components, this application proposes a sequential release surge protector, such as Figure 1-4 As shown, it includes a wave head absorption channel, a wavelength pre-emission channel and an energy release channel, which respectively absorb and release the wave head, wavelength and wave tail of lightning in an orderly manner.

[0022] The wave front absorption channel includes a transient voltage suppression diode (TVS) and a first zinc oxide varistor (M0). The transient voltage suppression diode (TVS) and the first zinc oxide varistor (M0) are connected in series, and the other end of the first zinc oxide varistor (M0) is grounded. Taking advantage of the fast response time of the transient voltage suppression diode (TVS), the transient voltage suppression diode (TVS) and the first zinc oxide varistor (M0) are connected in series to form a wave front absorption channel. When the leading edge of the lightning wave arrives, the transient voltage suppression diode (TVS) and the first zinc oxide varistor (M0) in the wave front absorption channel respond and conduct first, absorbing part of the wave front energy and reducing the steepness.

[0023] A second zinc oxide varistor M1 is connected in parallel across the transient voltage suppression diode TVS. The second zinc oxide varistor M1 and the first zinc oxide varistor M0 form a wavelength pre-emission channel. When the lightning wave voltage rises to the continuous operating voltage of the varistor M1, the wavelength pre-emission channel begins to respond and conduct, releasing and consuming part of the wavelength energy.

[0024] The second zinc oxide varistor M1 is connected in series with a gas discharge tube G, the other end of which is grounded. Leveraging the gas discharge tube G's strong current-carrying capacity and low residual voltage, the second zinc oxide varistor M1 and the gas discharge tube G form an energy release channel. When the voltage in the wavelength pre-emission channel rises to the breakdown voltage of the gas discharge tube G, the energy release channel fully responds and conducts, releasing a high-energy surge current. Because the voltage across the gas discharge tube G is as low as tens of volts after breakdown, the terminal voltage of the energy release channel is clamped to a low level by selecting the continuous operating voltage and current of the varistor M1 and the breakdown voltage and current of the gas discharge tube G, thereby reducing the residual voltage of the surge protector.

[0025] In this embodiment, the wave head absorption channel also includes a first voltage limiting resistor R1, which is connected in series with the transient voltage suppression diode TVS; the first voltage limiting resistor R1 is connected in series in the wave head absorption channel to divide the voltage, limit excessive current from flowing through the components on the wave head absorption channel, protect the circuit, and has higher safety and more stable operation.

[0026] In this embodiment, the wavelength pre-transmission channel also includes a second voltage-limiting resistor R2 connected in series between the second zinc oxide varistor M1 and the first zinc oxide varistor M0; the second voltage-limiting resistor R2 is connected in series on the wavelength pre-transmission channel to divide the voltage, limiting excessive current from flowing through the components on the wavelength pre-transmission channel, protecting the circuit, and ensuring higher safety and more stable operation.

[0027] In this embodiment, the input end of the first zinc oxide varistor M0 is connected in series with an overheating fuse AUPO. When the first zinc oxide varistor M0 is overheated and the degradation leakage current is too large, the overheating fuse AUPO is blown, and the first zinc oxide varistor M0 is cut off from the circuit, which can effectively prevent the first zinc oxide varistor M0 from catching fire and avoiding accidents. The input end of the second zinc oxide varistor M1 is connected in series with an overheating fuse card K1. When the second zinc oxide varistor M1 is overheated and the degradation leakage current is too large, the overheating fuse card K1 is disconnected, and the second zinc oxide varistor M1 is cut off from the circuit, thereby realizing overheat protection for the second zinc oxide varistor M1.

[0028] The residual voltage and varistor voltage (also known as the initial conduction voltage) of current metal oxide varistors (MOVs) are key technical parameters for voltage-limiting surge protectors. Under the same surge current, the residual voltage increases with the varistor voltage; lower varistor voltages result in lower residual voltage. This characteristic conflicts with the requirements of the protected equipment, which prefers a high varistor voltage and low residual voltage. This problem has long plagued the lightning protection industry. While lowering the varistor voltage can reduce the residual voltage, non-lightning factors—power surges caused by grid voltage fluctuations—can also trigger the MOV to operate when they exceed the varistor voltage. This not only shortens the MOV's service life but, if prolonged, can cause it to overheat and burn out, resulting in non-lightning damage. A passive approach, increasing the varistor voltage, often results in increased residual voltage and reduced protection. Current gas discharge tubes (GDTs) have a slow response time.

[0029] At present, most power surge protectors use U c / U 1mA For MOVs with (continuous operating voltage / varistor voltage) of 385 / 621 and 420 / 681, under the same technical conditions, the residual voltage increases with the increase of the surge current. The average residual voltage values ​​are as follows:

[0030] U c / U 1mA For 385 / 621 MOV:

[0031] Inrush current (20KA, 8 / 20us) residual voltage: about 1650V,

[0032] Inrush current (40KA, 8 / 20us) residual voltage: about 2300V,

[0033] Inrush current (60KA, 8 / 20us) residual voltage: about 2600V,

[0034] U c / U 1mA For 420 / 681 MOV:

[0035] Inrush current (20KA, 8 / 20us) residual voltage: about 1850V,

[0036] Inrush current (40KA, 8 / 20us) residual voltage: about 2550V,

[0037] Inrush current (60KA, 8 / 20us) residual voltage: about 2900V,

[0038] The sequential release surge protector of the present invention continues to operate at a voltage U c Greater than 600V, the residual voltage range is as follows:

[0039] Inrush current (20KA, 8 / 20us) residual voltage: <1100V,

[0040] Inrush current (40KA, 8 / 20us) residual voltage: <1400V,

[0041] Inrush current (60KA, 8 / 20us) residual voltage: <1700V

[0042] From the above data we can see that compared with U c / U 1mA For MOVs of 385 / 621, the residual voltage of the sequential release surge protector of the present application is reduced by 33%, 39%, and 35% respectively under the conditions of 20KA, 40KA, and 60KA impulse currents;

[0043] Compared to U c / U 1mA For a 420 / 681 MOV, the residual voltage of the sequential release surge protector of the present application is reduced by 41%, 45%, and 41% respectively under the conditions of 20KA, 40KA, and 60KA impulse currents.

[0044] In summary, the sequential release surge protector of this application overcomes the contradiction between the high initial conduction voltage (varistor voltage) and stable operation of the metal oxide varistor (MOV) and the low residual voltage for good protection. By utilizing the advantages of the gas discharge tube's strong current capacity and low residual voltage and the transient voltage suppression diode's fast response time, the metal oxide varistor (MOV), gas discharge tube, and transient voltage suppression diode (TVS) are combined into a surge protector. With only one level of sequential release surge protector, the effects of high initial conduction voltage, large current capacity, low residual voltage, and fast response speed can be achieved, effectively solving the problem of power system protection in narrow or isolated areas.

[0045] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. Sequential release surge protector, characterized in that, Including wave head absorption channel, wavelength pre-emission channel and energy release channel, The wave front absorption channel includes a transient voltage suppression diode TVS and a first zinc oxide varistor M0, wherein the transient voltage suppression diode TVS is connected in series with the first zinc oxide varistor M0, and the other end of the first zinc oxide varistor M0 is grounded; A second zinc oxide varistor M1 is connected in parallel at both ends of the transient voltage suppression diode TVS, and the second zinc oxide varistor M1 and the first zinc oxide varistor M0 form a wavelength pre-emission channel; The second zinc oxide varistor M1 is connected in series with a gas discharge tube G, the other end of which is grounded. The second zinc oxide varistor M1 and the gas discharge tube G form an energy release channel; the input end of the first zinc oxide varistor M0 is connected in series with an overheating fuse AUPO, which is electrically connected to one end of the transient voltage suppression diode TVS; the input end of the second zinc oxide varistor M1 is connected in series with an overheating fuse card K1, which is electrically connected to the other end of the transient voltage suppression diode TVS.

2. The sequential release surge protector according to claim 1, characterized in that: The wave front absorption channel also includes a first voltage limiting resistor R1, and the first voltage limiting resistor R1 is connected in series with a transient voltage suppressor diode TVS.

3. The sequential release surge protector according to claim 1, characterized in that: The wavelength pre-transmission channel further includes a second voltage-limiting resistor R2 connected in series between the second zinc oxide varistor M1 and the first zinc oxide varistor M0.

Images