KR102311307B1 - Emp protective device for rf antenna - Google Patents

Abstract

The present invention relates to an EMP protection device for blocking a very fast transient voltage/current caused by an electromagnetic pulse (EMP), wherein the EMP protection device comprises: a gas discharge tube (GDT) connected between a voltage line and a shielding line to primarily block a transient voltage signal due to the electromagnetic pulse (EMP); a D/C unit part comprising a first DC unit disposed at a rear end of the gas discharge tube and equipped with a plurality of forward diodes and a first capacitor connected in series between the voltage line and the shielding line, and a second DC unit equipped with a plurality of reverse diodes and a second capacitor connected in series between the voltage line and the shielding line; and a winding-type coaxial transformer disposed at a rear end of the D/C unit part to suppress the transient voltage signal passing through the D/C unit.

Description

EMP protection device for RF antenna

The present invention relates to an EMP protection device applicable to an antenna communication line or an RF communication line, and more particularly, to an EMP protection device capable of effectively blocking excessive voltage/current due to an electromagnetic pulse (EMP).

Recently, with the development of electric/electronic communication technology, the use of digital electric/electronic devices in industrial plants, companies, and general homes has been greatly expanded. However, since digital electric/electronic devices are very vulnerable to transient voltages generated by lightning or electromagnetic pulses (EMP), etc., there is a problem in that the possibility of damage to the device increases when the actual transient voltage is introduced. Therefore, the transient voltage protection device is widely used for the purpose of preventing damage to the device due to the excessive voltage.

Transient voltage protection device means a device that attenuates transient voltage or noise, and AC/DC power lines connected to telephone lines, data networks, CCTV circuits, cable TV circuits, or electronic/communication equipment; It is installed on the control line or communication line to attenuate the transient voltage. The transient voltage protection device includes a surge protection device for blocking a surge caused by lightning and an EMP protection device for blocking an excessive voltage due to an electromagnetic pulse (EMP).

The devices constituting the transient voltage protection device are largely divided into clamp devices and crowbar devices according to voltage/current characteristics. In the former case, an avalanche breakdown diode (ABD) and a metal oxide varistor (Metal Oxide Varistor, MOV) is mainly used, and in the latter case, a Gas Discharge Tube (GDT) and a Thyristor Surge Suppressor (TSS) are mainly used.

Among them, the gas discharge tube (GDT) has a shape in which two electrodes face each other inside a tube filled with an inert gas, and has a low self-capacitance compared to other devices (eg, silicon avalanche diode, metal oxide varistor, etc.) For this reason, it is mainly used for protection of transient voltages in communication-related circuits into which high-frequency signals are introduced. In addition, when a transient voltage applied to both ends of the gas discharge tube (GDT) is greater than a predetermined sparkover voltage, the gas discharge tube (GDT) is discharged to perform transient voltage protection.

1 is a view showing a transient voltage / current protection device according to the prior art. As shown in FIG. 1 , the conventional transient voltage/current protection device 10 _{is connected between a voltage line 11 to which a normal voltage signal (or a rated voltage signal, V c} ) is applied and the shielding line 12, Sh. and a gas discharge tube (13). _{When the transient voltage signal V s} due to lightning or electromagnetic pulse (EMP) is applied to the voltage line 11 so that the voltage at both ends of the gas discharge tube 13 is greater than the spark discharge voltage of the gas discharge tube 13, the gas discharge tube 13 is flow in the normal discharge current due to the normal voltage signal (V _c) (I _c) and the transient current (I _s) to ground (15, ground) by a transient voltage signal (V _s) direction.

On the other hand, most of the transient current Isg by the transient voltage signal Vsg that can be applied to the shielding line 12, Sh in a common mode (or common mode, common mode) flows to the ground 15, Gnd, Some current flows in the shielding layer (not shown) on the load 14 side. Therefore, the EMP filter standard requires that not only the differential mode (or normal mode, differential mode) transient current flowing to the load side but also the common mode transient current flowing through the shielding layer be suppressed to a predetermined value.

However, the conventional transient voltage/current protection device can effectively block the transient voltage/current caused by lightning, but with respect to the very fast transient voltage/current caused by an electromagnetic pulse (EMP), the two modes of transient current There is a problem that cannot be completely suppressed.

SUMMARY OF THE INVENTION The present invention aims to solve the above and other problems. Another object of the present invention is to provide an EMP protection device capable of effectively blocking a very fast transient voltage/current caused by an electromagnetic pulse (EMP).

Another object of the present invention is to provide an EMP protection device including a gas discharge tube (GDT), a D/C unit, and a winding coaxial transformer.

Another object is to provide an EMP protection device capable of responding to a pulse current injection (PCI) test.

According to an aspect of the present invention in order to achieve the above or other objects, it is connected between the voltage line and the shielding line, the gas discharge tube (GDT) for primarily blocking the transient voltage signal due to the electromagnetic pulse (EMP); a first DC unit disposed at a rear end of the gas discharge tube and having a first capacitor and a plurality of forward diodes connected in series between the voltage line and the shielding line; and a plurality of reverse directions connected in series between the voltage line and the shielding line. a D/C unit including a second DC unit including diodes and a second capacitor; And it is disposed at the rear end of the D/C unit, it provides an EMP protection device comprising a winding-type coaxial transformer for suppressing the transient voltage signal passing through the D/C unit.

More preferably, the DC unit is characterized in that it has a breakdown voltage corresponding to the number of bidirectional diodes connected in series between the voltage line and the shielding line. In addition, when the voltage at both ends of the DC unit is greater than its breakdown voltage, the DC unit conducts between the voltage line and the shielding line, and the transient current due to the transient voltage signal passing through the gas discharge tube flows in the ground direction. It is characterized in that it is controlled to

More preferably, the wire-wound coaxial transformer is composed of a magnetic core and a coaxial cable surrounding the magnetic core, a central conductor of the coaxial cable is connected to the voltage line, and an outer conductor of the coaxial cable is connected to the shielding line. characterized by being connected. In addition, the winding type coaxial transformer is characterized in that it passes the normal voltage signal corresponding to the differential mode signal as it is, and blocks the transient voltage signal corresponding to the common mode signal.

The effect of the EMP protection device according to the embodiments of the present invention will be described as follows.

According to at least one of the embodiments of the present invention, a very fast differential mode and a common mode due to an electromagnetic pulse (EMP) using an EMP protection device including a gas discharge tube (GDT), a D/C unit unit and a winding type coaxial transformer It has the advantage of being able to effectively block the transient voltage/current of

However, the effects that can be achieved by the EMP protection device according to the embodiments of the present invention are not limited to those mentioned above, and other effects not mentioned are common knowledge in the technical field to which the present invention belongs from the description below. It can be clearly understood by those who have

1 is a view showing a transient voltage/current protection device according to the prior art;
Figure 2 is a view showing the configuration of the EMP protection device according to an embodiment of the present invention;
Figure 3 is a view showing the types of filters applicable to the EMP protection device of Figure 2;
Figure 4 is a diagram illustrating a configuration of the D/C unit installed in the EMP protection device of Figure 2;
Figure 5 is a view for explaining the configuration and symbols of the winding-type coaxial transformer installed in the EMP protection device of Figure 2;
6 is a diagram referenced to explain the operation of the EMP protection device according to an embodiment of the present invention;
7 is a view showing the configuration of an EMP protection device according to another embodiment of the present invention;
8 is a view showing the configuration of an EMP protection device according to another embodiment of the present invention;
Fig. 9 is a diagram illustrating a bar-piler transformer used in the EMP protection device of Fig. 8;
10 is a diagram illustrating a method of verifying the performance of an EMP protection device for an RF antenna;
11 is a diagram illustrating a waveform of a transient current due to an electromagnetic pulse (EMP) and an output current waveform of the EMP protection device.

Hereinafter, the embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but the same or similar components are assigned the same reference numerals regardless of reference numerals, and overlapping descriptions thereof will be omitted. In addition, in describing the embodiments disclosed in the present specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical spirit disclosed herein is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present invention , should be understood to include equivalents or substitutes.

The present invention proposes an EMP protection device capable of effectively blocking a very fast transient voltage/current caused by an electromagnetic pulse (EMP). In addition, the present invention proposes an EMP protection device including a gas discharge tube (GDT), a D/C unit and a winding type coaxial transformer. In addition, the present invention proposes an EMP protection device including a gas discharge tube (GDT), a D/C unit unit, a winding type coaxial transformer, and one or more filters.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the drawings.

2 is a diagram showing the configuration of an EMP protection device according to an embodiment of the present invention.

Referring to FIG. 2 , the EMP protection device 100 according to an embodiment of the present invention includes a voltage line 110 , a shielding line 120 , a gas discharge tube 130 , a filter unit 140 , and D/ It includes a C unit unit 150 , a winding type coaxial transformer 160 , and a ground 170 .

The enclosure of the EMP protection device 100 is made of metal, and is electrically connected to the shielding wire 120 in common.

The voltage line 110 may be a central conductor (or a core wire) of a coaxial cable (not shown), and the return current of the signal flows to the shielding line (layer). The shielding line 120 may be an external conductor (or shield) of the coaxial cable.

A normal voltage signal V _c is applied between the voltage line 110 and the shielding line 120 , and a voltage source providing _{the normal voltage signal V c to the voltage line 110 and the shielding line 120 .} (not shown) and a _{load 50 receiving the normal voltage signal V c} may be connected.

A gas discharge tube (GDT) 130 may be connected between the voltage line 110 and the shielding line 120 . The gas discharge tube 130 may be connected in parallel with the load 50 .

The gas discharge tube 130 is a discharge tube containing an inert gas in a ceramic container and using an alloy electrode. The gas discharge tube 130 has a predetermined sparkover voltage for protecting the load from excessive voltage.

When the spark discharge voltage of the gas discharge tube 130 is set higher than the voltage level of the normal voltage signal V _c , the gas discharge tube 130 does not react (operate) to the _{normal voltage signal V c , so that the} The steady current (I _c ) by the steady voltage signal (V _c ) flows only in the direction of the load (50) without flowing into the gas discharge tube (130).

On the other hand, when the transient voltage signal V _s due to the electromagnetic pulse EMP is applied to the voltage line 110 so that the voltage at both ends of the gas discharge tube 130 is greater than the spark discharge voltage of the gas discharge tube 130, the gas the discharge tube 130, the discharge (or opening) the normal voltage signal (V _c) steady-state current (I _c) and the transient current (I _s) to ground (170, ground) by a transient voltage signal (V _s) by way to flow to Accordingly, the gas discharge tube 130, when the transient voltage signal (V _s ) due to the electromagnetic pulse (EMP) is applied, the transient current (I _s ) due to the transient voltage signal (V _s ) in the direction of the load 50 . Flow can be primarily suppressed.

The filter unit 140 is disposed between the gas discharge tube 130 and the load 50 , and serves to block or suppress a specific frequency component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

In an embodiment, the filter unit 140 is disposed between the gas discharge tube 130 and the D/C unit unit 150 , and may include at least one of a high pass filter 141 and a DC filter 143 . can

The high frequency filter 141 serves to block (or filter) the low frequency component of the transient voltage/current caused by the electromagnetic pulse (EMP). That is, the high frequency filter 141 may block the low frequency component of the excessive voltage/current passing through the gas discharge tube 130 . The high frequency filter 141 may include a capacitor element C connected in parallel between the voltage line 110 and the shielding line 120 , but is not limited thereto.

The DC filter 143 serves to block (or filter) the DC component of the transient voltage/current caused by the electromagnetic pulse (EMP). That is, the DC filter 143 may block the DC component of the transient voltage/current passing through the gas discharge tube 130 . The DC filter 143 may include a capacitor element C connected in series on the voltage line 110 , but is not limited thereto.

Meanwhile, as another embodiment, as shown in FIG. 3 , the filter unit 140 may include at least one of a low pass filter ( 145 , 147 ) and a band pass filter ( 149 ). .

The low-frequency filters 145 and 147 serve to block (or filter) the high-frequency component of the transient voltage/current caused by the electromagnetic pulse (EMP). That is, the low-frequency filters 145 and 147 may block high-frequency components of the transient voltage/current passing through the gas discharge tube 130 . These low-frequency filters 145 and 147 are composed of a capacitor element C connected in parallel between the voltage line 110 and the shielding line 120 and an inductor element L connected in series on the voltage line 110 or It may be composed of an inductor element L connected in series on the voltage line 110 , but is not necessarily limited thereto.

The band-pass filter 149 serves to block (or filter) the low-frequency and high-frequency components of the transient voltage/current caused by the electromagnetic pulse (EMP). That is, the band-pass filter 149 may simultaneously block the low-frequency and high-frequency components of the transient voltage/current passing through the gas discharge tube 130 . The band-pass filter 149 may include, but is not limited to, a capacitor element C and an inductor element L having a parallel structure connected to the voltage line 110 .

Meanwhile, in the present embodiment, although one filter unit is illustrated to be installed in the EMP protection device 100, it is not necessarily limited thereto, and it will be apparent to those skilled in the art that a plurality of filter units may be installed in the EMP protection device. In addition, although it is exemplified that the filter unit is disposed between the gas discharge tube 130 and the D/C unit unit 150 , it is not necessarily limited thereto, and between the D/C unit unit 150 and the winding type coaxial transformer 160 . Alternatively, it will be apparent to those skilled in the art that it may be disposed between the winding type coaxial transformer 160 and the load 50 .

The D/C unit 150 may be disposed between the gas discharge tube 130 and the load 50 , more preferably between the filter unit 140 and the winding type coaxial transformer 160 . In this case, the D/C unit 150 may be connected in parallel with the load 50 between the voltage line 110 and the shielding line 120 .

The D/C unit 150 includes a plurality of diodes 151a and 153a and two capacitors 151b and 153b. Here, the plurality of diodes 151a and 153a have a fast response speed of several nanoseconds and a small capacitance of several pF. The capacitors 151a and 153a have a capacitance of several uF.

The D/C unit 150 may include a first D/C unit 151 and a second D/C unit 153 connected between the voltage line 110 and the shielding line 120 . In this case, the first D/C unit 151 and the second D/C unit 153 may be connected in parallel between the voltage line 110 and the shielding line 120 .

4 , the first D/C unit 151 may include a plurality of forward diodes 151a and a first capacitor 151b. Here, the plurality of forward diodes 151a and the first capacitor 151b may be connected in series between the voltage line 110 and the shielding line 120 . The first capacitor 151b is exemplified to be disposed between the forward diode 151a of the last order and the shielding line 120, but is not limited thereto, and is disposed between the voltage line 110 and the forward diode of the first order ( 151a).

The second D/C unit 153 may include a plurality of reverse diodes 153a and a second capacitor 153b. Similarly, the plurality of reverse diodes 153a and the second capacitor 153b may be connected in series between the voltage line 110 and the shielding line 120 . The second capacitor 153b is exemplified to be disposed between the last-order forward diode 153a and the shielding line 120, but is not limited thereto, and is disposed between the voltage line 110 and the first-order forward diode ( 153a).

When an electromagnetic pulse (EMP) is applied from the outside, it is advantageous that the device connected to the ground has a large capacitance in order to classify (flow) the pulse to the ground. Therefore, in the case of a D/C unit in which a diode having a capacitance of several pF and a capacitor having a capacitance of several uF are connected in series, the first capacitor 151b located on the left operates with respect to the forward electromagnetic pulse, and the first capacitor 151b is operated in the reverse direction. With respect to the electromagnetic pulse, the second capacitor 153b positioned on the right operates to effectively classify the electromagnetic pulse in the ground direction.

When the breakdown voltage of the D/C unit 150 is set to be greater than the voltage level of the normal voltage signal V _{c through this connection method, the D/C unit 150 is the normal voltage signal V c} ). Since it does not react (operation) to the normal voltage signal (V _c ), the normal current (I _c ) does not flow to the D/C unit unit 150 but flows only in the direction of the load 50 .

On the other hand, when a positive transient voltage signal V _s due to the electromagnetic pulse EMP is applied to the voltage line 110 , the forward diodes 151a of the D/C unit 150 are conducted, and the first capacitor ( As the voltage line 110 and the shielding line 120 rapidly conduct (or open) due to the small impedance of 151b), the transient current I _{s caused by the positive transient voltage signal V s} is reduced to the shielding line 120. ) through the ground (170, ground) to flow in the direction.

In addition, when a negative transient voltage signal (V _s ) due to the electromagnetic pulse (EMP) is applied to the voltage line 110 , the reverse diodes 153a of the D/C unit unit 150 become conductive, and the second capacitor ( As the voltage line 110 and the shielding line 120 rapidly conduct (or open) due to the small impedance of 153b), the transient current I _{s by the negative transient voltage signal V s} 120) through the ground (170, ground) to flow in the direction.

On the other hand, when the D/C unit is applied to the high-voltage transmission antenna, most of the high-voltage is handled through voltage distribution in a capacitor having a capacitance of several uF. And, since the junction capacitance of the diode is very small, several pF, the total capacitance of the D/C unit is governed by the junction capacitance of the diode, so it is advantageous for the passage of high-frequency signals and can be applied to RF high-frequency signal circuits. . That is, when voltage is applied, most of the voltage is applied to the capacitor, and the equivalent capacitance between the signal line and the ground becomes several pF.

The winding type coaxial transformer (or winding type coaxial coil, 160) may be disposed between the gas discharge tube 130 and the load 50, more preferably between the D/C unit unit 150 and the load 50. .

The wire-wound coaxial transformer 160 may include one magnetic core and a coaxial cable surrounding the magnetic core.

For example, as shown in FIG. 5 , the wire-wound coaxial transformer 160 includes a ring-shaped magnetic core 161 and coaxial cables 163 and 165 surrounding the magnetic core 161 in a predetermined direction. can be In this case, the central conductor (ie, the core wire, 163 ) of the coaxial cable may be connected to the voltage line 110 , and the outer conductor 165 of the coaxial cable may be connected to the shielding line 120 .

Wire-wound coaxial transformer 160, as a kind of common mode choke, has an impedance of 0 with respect to a differential mode signal, passes the signal without attenuation, and for a common mode signal that can flow in the shielding layer It has a very high impedance and serves to suppress the corresponding signal.

In this embodiment, the winding type coaxial transformer 160 can pass the normal voltage signal applied to the voltage line 110 to the load terminal without distortion by making the series leakage inductance very small. In addition, since the wire-wound coaxial transformer 160 has a very high impedance with respect to the common mode signal, it is possible to suppress the transient voltage signal due to the electromagnetic pulse EMP corresponding to the common mode signal. That is, the winding type coaxial transformer 160 can smoothly pass the normal voltage signal corresponding to the differential mode signal and effectively block the transient voltage signal corresponding to the common mode signal.

As described above, in the EMP protection device according to an embodiment of the present invention, the electromagnetic pulse passing through the gas discharge tube ( It can effectively block very fast transient voltage/current caused by EMP).

6 is a diagram referenced to explain the operation of the EMP protection apparatus according to an embodiment of the present invention.

As shown in FIG. 6 , when the normal voltage signal V _c is applied to the voltage line 110 , the voltage level of the normal voltage signal V _c is smaller than the spark discharge voltage of the gas discharge tube 130 , The gas discharge tube 130 does not operate. In addition, the filter unit 140 passes the normal voltage signal V _c corresponding to the operating frequency band as it is. Thereafter, since the impedance applied to both ends of the D/C unit 150 is large, the D/C unit 150 does not operate. Finally, the winding type coaxial transformer 160 passes the normal voltage signal (V _c ) corresponding to the differential mode signal as it is. Therefore, since both the gas discharge tube 130 and the D/C unit 150 are in a high impedance state, the steady current I _{C by the steady voltage signal V c} flows only in the direction of the load 50 .

In this state, when a very fast transient voltage signal (V _s ) due to the electromagnetic pulse (EMP) is applied to the voltage line 110 , the voltage at both ends of the gas discharge tube 130 is greater than the spark discharge voltage of the gas discharge tube 130 . , the gas discharge tube 130 is discharged (or opened) so that the normal current I _{c by the normal voltage signal V c} flows in the ground direction. In addition, the gas discharge tube 130 allows a portion of the transient current I _s1 of the transient current I _{s by the transient voltage signal V s} to flow in the ground direction.

Since the gas discharge tube 130 does not have a fast response speed to the transient voltage signal, it cannot completely block the very fast transient voltage/current caused by the electromagnetic pulse (EMP). Therefore, the excessive voltage/current that has not yet been cut off by the gas discharge tube 130 , the high frequency filter 141 , the DC filter 143 , the D/C unit 150 , and the winding type coaxial installed at the rear end of the gas discharge tube 130 . It may be sequentially removed through the transformer 160 .

A high frequency filter 141 is over-voltage signal (V _s) having passed through the gas discharge tube 130 which may block the low frequency component of the over-voltage signal (V _s), DC filter 143 through the gas discharge tube (130) can block the DC component of In addition, since the voltage across both ends of the D/C unit 150 is greater than the breakdown voltage of the D/C unit 150 , the D/C unit 150 is disposed between the voltage line 110 and the shielding line 120 . conducts (or opens) at a very high speed to allow some of the transient currents _{I s4 to pass through the DC filter 143 (I s5} ) to flow in the ground direction.

The wire-wound coaxial transformer 160 may block _{some transient currents I s6 passing through the D/C unit 150 .} Thereafter, when the transient voltage signal (V _s ) applied to the voltage line 110 disappears through the ground, the gas discharge tube 130 and the D/C unit unit 150 of the EMP protection device 100 return to their original state. do.

7 is a diagram showing the configuration of an EMP protection device according to another embodiment of the present invention.

Referring to FIG. 7 , the EMP protection device 200 according to another embodiment of the present invention includes a voltage line 210 , a shielding line 220 , a gas discharge tube 230 , a filter unit 240 , and a plurality of D/C units. It includes parts 250 and 260, a wire-wound coaxial transformer 270 and a ground (not shown, ground).

The voltage line 210 , the shielding line 220 , the gas discharge tube 230 , the filter unit 240 and the winding type coaxial transformer 270 of the EMP protection device 200 are the voltage line 110 of FIG. 2 , the shielding line 120 , the gas discharge tube 130 , the filter unit 140 , and the winding type coaxial transformer 160 , so a detailed description thereof will be omitted.

The EMP protection device 200 according to this embodiment, unlike the EMP protection device 100 of FIG. 2 , a plurality of D/C units connected in parallel between the filter unit 240 and the winding type coaxial transformer 260 . (250, 260) may be provided. This is to increase the absorption capacity of the transient current caused by the electromagnetic pulse (EMP).

Each of the D/C unit units 250 and 260 may include the same number of forward diodes and reverse diodes. Accordingly, the breakdown voltage of the first D/C unit 250 and the breakdown voltage of the second D/C unit 260 may be identical to each other.

Meanwhile, in another embodiment, one or more filters may be disposed between each D/C unit. In this case, each D/C unit may include different numbers of forward diodes and reverse diodes.

As described above, in the EMP protection device according to another embodiment of the present invention, by disposing a filter unit, a plurality of D/C unit units, and a winding type coaxial transformer at the rear end of the gas discharge tube, very It can effectively block fast transient voltage/current.

8 is a diagram showing the configuration of an EMP protection device according to another embodiment of the present invention.

Referring to FIG. 8 , an EMP protection device 300 according to another embodiment of the present invention is an EMP protection device for an RF antenna, and includes a body case 301 , an input connector 302 , a first communication line 303 , and a first 2 communication lines 304, gas discharge tube 305, first and second high frequency filters 306 and 315, first and second DC filters 307 and 311, first and second low frequency filters 310 and 318 , band pass filter 314 , first to sixth D/C unit parts 308 , 309 , 312 , 313 , 316 , 317 , wire-wound coaxial transformer 319 , insulating member 320 and output connector 321 ) may be included.

The gas discharge tube 305, the first high frequency filter 306, the first DC filter 307, the D/C unit parts 308, 309, 312, 313, 316, 317 of the EMP protection device 300, and the winding type The coaxial transformer 319 is the same as or similar to the gas discharge tube 130, the high frequency filter 141, the DC filter 143, the D/C unit 150 and the winding type coaxial transformer 160 of FIG. 2 described above. A detailed description thereof will be omitted.

The body case 301 serves to protect the components of the EMP protection device 300 . The body case 301 is formed to have an internal space for accommodating various electronic components.

The input connector 301 is disposed on one side of the body case 301 and is connected to the first coaxial cable 801 . The output connector 321 is disposed on the other side of the body case 301 and is connected to the second coaxial cable 803 .

An insulating member 320 may be disposed between the body case 301 and the output connector 321 . The insulating member 320 insulates between the body case 301 and the output connector 321 . This is to pass the Pulsed Current Injection (PCI) test, which is one of the international test standards required to verify the performance of the EMP protection device.

The first communication line 303 may be electrically connected to a central conductor (or a core wire, not shown) of the first and second coaxial cables 801 and 803 through the input/output connectors 302 and 321 . The second communication line 304 may be electrically connected to an external conductor (or shield, not shown) of the first and second coaxial cables 801 and 803 through the input/output connectors 302 and 321 .

The gas discharge tube 305 is disposed between the input connector 302 and the first high frequency filter 306 and may be connected in parallel between the first communication line 303 and the ground. When the transient voltage signal (V _s ) is applied to the first communication line 303, the gas discharge tube 305 conducts between the first communication line 303 and the ground to conduct the transient current ( _{V s) by the transient voltage signal (V s)} A _{part of I s} ) flows in the direction of the ground.

The first high frequency filter 306 is disposed between the gas discharge tube 305 and the first DC filter 307 , and may be connected in parallel between the first communication line 303 and the ground. The first high frequency filter 306 may block a low frequency component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The first DC filter 307 is disposed between the first high frequency filter 306 and the first and second D/C unit units 308 and 309 , and may be connected in series on the first communication line 303 . The first DC filter 307 may block a DC component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The first and second D/C unit units 308 and 309 are disposed between the first DC filter 307 and the first low-frequency filter 310, and are paralleled between the first communication line 303 and the ground. can be connected to In this case, the first and second D/C unit units 308 and 309 may include the same number of forward diodes and reverse diodes. When the transient voltage signal V _s is applied to the first communication line 303 , the first and second D/C unit units 308 and 309 conduct between the first communication line 303 and the ground to conduct the transient voltage A portion of the transient current I _{s by the signal V s} flows in the ground direction.

The first low-frequency filter 310 may be disposed between the first and second D/C unit units 308 and 309 and the second DC filter 311 . The first low-frequency filter 310 may block a high-frequency component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The second DC filter 311 is disposed between the first low frequency filter 310 and the third and fourth D/C unit units 312 and 313 , and may be connected in series on the first communication line 303 . The second DC filter 311 may block the DC component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The third and fourth D/C unit units 312 and 313 are disposed between the second DC filter 311 and the band-pass filter 314, and are paralleled between the first communication line 303 and the ground. can be connected In this case, the third and fourth D/C unit units 312 and 313 may include the same number of forward diodes and reverse diodes. Meanwhile, the third and fourth D/C unit units 312 and 313 may include different numbers of forward diodes and reverse diodes from those of the first and second D/C unit units 308 and 309 . When the transient voltage signal V _s is applied to the first communication line 303 , the third and fourth D/C unit units 312 and 313 conduct between the first communication line 303 and the ground to conduct the transient voltage A portion of the transient current I _{s by the signal V s} flows in the ground direction.

The band pass filter 314 is disposed between the third and fourth D/C unit units 312 and 313 and the second high frequency filter 315 , and may be connected in series on the first communication line 303 . The band-pass filter 314 may simultaneously block a low-frequency component and a high-frequency component _{of the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The second high frequency filter 315 is disposed between the band pass filter 314 and the fifth and sixth D/C unit units 316 and 317, and is disposed in parallel between the first communication line 303 and the ground. can be connected The second high frequency filter 315 may block a low frequency component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The fifth and sixth D/C unit units 316 and 317 are disposed between the second high-frequency filter 315 and the second low-frequency filter 318, and are parallel to the first communication line 303 and the ground. can be connected to In this case, the fifth and sixth D/C unit units 316 and 317 may include the same number of forward diodes and reverse diodes. On the other hand, the fifth and sixth D/C unit units 316 and 317 have forward diodes and reverse diodes in numbers different from those of the first to fourth D/C unit units 308 , 309 , 312 and 313 . can do. When the transient voltage signal V _s is applied to the first communication line 303 , the fifth and sixth D/C unit units 316 and 317 conduct between the first communication line 303 and the ground to conduct the transient voltage A portion of the transient current I _{s by the signal V s} flows in the ground direction.

The second low-frequency filter 318 is disposed between the fifth and sixth D/C unit parts 316 and 317 and the wire-wound coaxial transformer 319 , and may be connected in series on the first communication line 303 . The second low-frequency filter 318 may block a high-frequency component of _{the transient voltage signal V s caused by the electromagnetic pulse EMP.}

The wire-wound coaxial transformer 319 is disposed between the second low-frequency filter 318 and the output connector 321, and may include a magnetic core and two coils surrounding the magnetic core. At this time, the first coil of the wire-wound coaxial transformer 319 may be connected in series on the first communication line 303 , and the second coil of the corresponding transformer 319 may be connected in series on the second communication line 304 . have. The wire-wound coaxial transformer 319 can smoothly pass the normal voltage signal corresponding to the differential mode signal and effectively block the transient voltage signal corresponding to the common mode signal.

Meanwhile, as another embodiment, as shown in FIG. 9 , the wire-wound coaxial transformer 319 may include a magnetic core 910 and a coaxial cable 920 surrounding the magnetic core 910 . At this time, one end of the coaxial cable 920 may be connected to the second low frequency filter 318 mounted on the PCB board, and the other end may be connected to the output connector 321 . In addition, the coaxial cable 920 may be composed of a central conductor, an insulator, an outer conductor, and a sheath.

As described above, the EMP protection device according to another embodiment of the present invention passes through the gas discharge tube by disposing a plurality of filters, a plurality of D/C unit units, and a winding type coaxial transformer at the rear end of the gas discharge tube. It can effectively block very fast transient voltage/current. In addition, the EMP protection device is applicable not only to electrical/electronic equipment for supplying power to a load, but also to RF communication equipment using a coaxial cable.

10 is a diagram illustrating a method of verifying the performance of the EMP protection device 300 for an RF antenna. That is, FIG. 10 (a) is a test method for measuring the current flowing in the external contact of the output connector mounted on the EMP protection device when the transient voltage signal is applied, and FIG. 10 (b) is the transient voltage signal This is a test method that measures the current flowing through the center contact of the output connector mounted on the EMP protection device when applied.

The test method shown in (a) and (b) of FIG. 10 is a PCI test for verifying the performance of the EMP protection device 300, and the current flowing through the center connection part and the external connection part of the output connector 321 is the threshold current ( 0.1A) or less must be satisfied.

First, as shown in (a) of FIG. 10 , a resistance element (50Ω) for impedance matching is connected between the center connection part of the output connector 321 and the ground, and between the external connection part of the output connector 321 and the ground. It is possible to test the performance of the EMP protection device 300 in a state in which the current measuring device (CT) is connected to the. EMP protection device 300 according to the present invention by disposing the insulating member 320 between the body case 301 and the output connector 321, the current flowing through the external connection of the output connector 321 is a predetermined threshold current (0.1A) or less can pass the PCI test.

Next, as shown in (b) of FIG. 10, in a state in which a resistance element (50Ω) and a current measuring device (CT) for impedance matching are connected in series between the central connection part and the external connection part of the output connector 321 The performance of the EMP protection device 300 can be tested. In the EMP protection device according to the present invention, by disposing the insulating member 320 between the body case 301 and the output connector 321, the current flowing in the central connection portion of the output connector 321 is reduced to a predetermined threshold current (0.1A). ) or lower to pass the PCI test.

11 is a diagram illustrating the waveform of the transient current due to the electromagnetic pulse (EMP) and the output current waveform of the EMP protection device. 11, when a very fast transient current (τ _R = 20 nsec, FWHM = 500 ~ 550 nsec) due to an electromagnetic pulse (EMI) is applied to the input terminal of the EMP protection device (100, 200, 300), It can be seen that the EMP protection devices 100, 200, and 300 can effectively block the transient current caused by the electromagnetic pulse (EMI) by using a gas discharge tube, a filter unit, a D/C unit unit, and a winding type coaxial transformer. .

Meanwhile, although specific embodiments of the present invention have been described above, various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention is not limited to the described embodiments, and should be defined by the following claims as well as the claims and equivalents.

100: EMP protection device 110: voltage line
120: shielding line 130: gas discharge tube
140: filter unit 150: D/C unit unit
160: winding type coaxial transformer

Claims (4)

a gas discharge tube (GDT) connected between the voltage line and the shielding line to primarily block the transient voltage signal due to the electromagnetic pulse (EMP);
a plurality of forward diodes disposed at the rear end of the gas discharge tube and connected in series between the voltage line and the shielding line, each having a capacitance in units of picofarads (pF), and a second diode having a capacitance in units of microfarads (μF) A first DC unit having one capacitor, a plurality of reverse diodes having a capacitance of picofarads (pF) connected in series between the voltage line and the shielding line, and a capacitance of microfarads (μF) a plurality of D/C unit units including a second DC unit having a second capacitor having a second capacitor; and
It is disposed at the rear end of the plurality of D / C unit, including a winding type coaxial transformer for suppressing the transient voltage signal passing through the plurality of D / C unit,
Each D/C unit is connected in parallel between the voltage line and the shielding line,
EMP protection device, characterized in that the number of reverse diodes provided in the second DC unit corresponds to the number of forward diodes provided in the first DC unit. According to claim 1,
The DC unit has a breakdown voltage corresponding to the number of bidirectional diodes connected in series between the voltage line and the shielding line,
When the voltage at both ends of the DC unit is greater than the breakdown voltage of the DC unit, the DC unit conducts between the voltage line and the shielding line so that the transient current caused by the transient voltage signal passing through the gas discharge tube is grounded. EMP protection device, characterized in that the control to flow in the direction. According to claim 1,
The wire-wound coaxial transformer is composed of a magnetic core and a coaxial cable surrounding the magnetic core, a central conductor of the coaxial cable is connected to the voltage line, and an outer conductor of the coaxial cable is connected to the shielding line,
The winding-type coaxial transformer passes the normal voltage signal corresponding to the differential mode signal as it is, and blocks the transient voltage signal corresponding to the common mode signal.
body case;
an input connector disposed on one side of the body case and connected to a first coaxial cable;
an output connector disposed on the other side of the body case and connected to a second coaxial cable;
an insulating member disposed between the body case and the output connector to electrically insulate the body case and the output connector;
a first communication line electrically connected to the central conductor of the first and second coaxial cables;
a second communication line electrically connected to an external conductor of the first and second coaxial cables;
a gas discharge tube (GDT) that is connected between the first communication line and the ground and primarily blocks a transient voltage signal due to an electromagnetic pulse (EMP);
a first DC unit disposed at a rear end of the gas discharge tube, the first DC unit including a plurality of forward diodes and a first capacitor connected in series between the first communication line and the ground; a plurality of D/C unit units including a second DC unit including a plurality of reverse diodes and a second capacitor connected thereto; and
A winding type coaxial transformer disposed at a rear end of the plurality of D/C units to suppress an overvoltage signal passing through the plurality of D/C units,
EMP protection device for RF antenna, characterized in that each D/C unit is connected in parallel between the first communication line and the ground.

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