CN213398694U - Optical current transformer - Google Patents
Optical current transformer Download PDFInfo
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- CN213398694U CN213398694U CN202021388717.5U CN202021388717U CN213398694U CN 213398694 U CN213398694 U CN 213398694U CN 202021388717 U CN202021388717 U CN 202021388717U CN 213398694 U CN213398694 U CN 213398694U
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Abstract
The utility model discloses an optical current transformer, which comprises a sensing head component and an insulator, wherein the sensing head component comprises a sensing head shell, an optical sensing ring component and at least one flexible connecting component; the sensing head shell is connected to the upper end part of the insulator; a conductor channel for passing through a conductor and a ring groove arranged on the outer side of the conductor channel are arranged in the sensing head shell; the flexible connecting part is connected to the sensing head shell and is positioned in the annular groove; the optical sensing ring assembly is mounted in the annular groove, connected to the flexible connecting member and used for sensing current in the conductor to generate an optical signal. The utility model discloses can eliminate the influence of outside vibrations to current measurement precision, improve current measurement's precision and degree of accuracy.
Description
Technical Field
The utility model relates to an optics current transformer.
Background
At present, along with the increase of the capacity of a power grid and the improvement of the current and voltage grade, the optical current transformer is gradually popularized and used in an intelligent transformer substation due to the advantages of simple structure, difficulty in saturation, strong harmonic measurement and the like. The optical current transformer generates an optical signal by sensing an electrical current signal, and then converts the optical signal into a digital signal to measure the magnitude of the electrical current, but external vibration may cause the optical signal sensed by the optical current transformer to be inaccurate and deviate from an actual value, thereby affecting the measurement accuracy. And the measurement accuracy of the optical current transformer is influenced by temperature change, circulation and long-distance transmission of optical signals, so that the measurement accuracy deviates from a standard value.
Disclosure of Invention
The utility model aims to solve the technical problem that overcome prior art's defect, provide an optics current transformer, it can eliminate the influence of outside vibrations to current measurement precision, improves current measurement's precision and degree of accuracy.
In order to solve the technical problem, the technical scheme of the utility model is that: an optical current transformer comprises a sensing head assembly and an insulator, wherein the sensing head assembly comprises a sensing head shell, an optical sensing ring assembly and at least one flexible connecting part; wherein the content of the first and second substances,
the sensing head shell is connected to the upper end part of the insulator;
a conductor channel for passing through a conductor and a ring groove arranged on the outer side of the conductor channel are arranged in the sensing head shell;
the flexible connecting part is connected to the sensing head shell and is positioned in the annular groove;
the optical sensing ring assembly is mounted in the annular groove, connected to the flexible connecting member and used for sensing current in the conductor to generate an optical signal.
Further provided is a specific structure of the sensing head shell, wherein the sensing head shell comprises a shell body and a cover plate; wherein the content of the first and second substances,
the shell body is internally provided with an inner annular wall, an outer annular wall and an end wall, the inner periphery of the end wall is connected with the inner annular wall, the outer periphery of the end wall is connected with the outer annular wall, and the inner annular wall, the outer annular wall and the end wall surround at least one part of the ring groove;
the cover plate is connected to the shell body and used for sealing the annular groove, and an inner annular surface used for being abutted against the end surface of the inner annular wall and an outer annular surface used for being abutted against the end surface of the outer annular wall are arranged at one end part, close to the shell body, of the cover plate;
the conductor passage penetrates through the shell body and the cover plate.
In order to further avoid the formation of a circulation between the shell body and the cover plate, at least one of the inner annular surface and the outer annular surface is provided with an insulating oxide layer, and/or the end surface of the cover plate far away from the shell body is provided with an insulating oxide layer.
Further provided is a concrete structure of the flexible connecting component, which comprises a screw part, a flexible cushion and a threaded hole component; wherein the content of the first and second substances,
the screw part is connected in the sensing head shell;
the flexible cushion is connected to the screw rod part;
the threaded hole part is embedded in the flexible pad;
the optical sensing ring assembly is connected to the flexible pad by fasteners connected in the threaded hole parts.
Further, in order to convert the optical signal into a digital signal, the optical current transformer further comprises an acquisition unit and an optical cable; wherein the content of the first and second substances,
one end of the optical cable is connected with the acquisition unit, and the other end of the optical cable is connected with the optical sensing ring assembly;
the acquisition unit is used for receiving the optical signal generated by the optical sensing ring assembly through the optical cable and converting the optical signal into a digital quantity signal.
Further, in order to shorten the length of the optical cable to shorten the transmission distance of the optical signal, the insulator is connected to an external mounting bracket on which the pickup unit is mounted.
Further, the optical cable extends into the insulator from the lower end part of the insulator, penetrates through the insulator and then is connected with the optical sensing ring assembly.
Further, in order to avoid the influence on the current measurement accuracy caused by overhigh temperature, the optical current transformer further comprises a ground cabinet body and a sun shade; wherein the content of the first and second substances,
the acquisition unit is arranged in the in-place cabinet box body;
the floor cabinet box body is arranged in the sunshade.
Further in order to maintain the temperature stability of the acquisition unit, a shutter is arranged on the sunshade.
And further, in order to improve the protection grade of the in-place cabinet body and the sun shade, the in-place cabinet body and/or the sun shade are sealed by adopting a foamed silica gel adhesive tape.
After the technical scheme is adopted, the optical sensing ring assembly senses the current in the conductor to generate an optical signal, and the acquisition unit receives the optical signal generated by the optical sensing ring assembly through the optical cable and converts the optical signal into a digital quantity signal so as to measure the magnitude of the current in the conductor. The optical sensing ring assembly is connected to the flexible connecting part, so that the optical sensing ring assembly is not influenced by vibration of the sensing head shell, interference of external vibration on optical signals generated by sensing of the optical sensing ring assembly is eliminated, and further influence of the external vibration on current measurement precision is eliminated.
At least one of the inner ring surface and the outer ring surface is provided with an insulating oxide layer, so that the circulation generated between the shell body and the cover plate due to the current change in the conductor can be effectively avoided, and the influence of the circulation on the current measurement precision in the conductor is avoided. The collection unit is installed nearby on the outside mounting bracket, can shorten the length of optical cable to shorten optical signal's transmission distance, avoid optical signal to appear damaging in the in-process of transmission in the optical cable, and then improved current measurement's precision and degree of accuracy. The ground cabinet body and the sun shade form a double-layer structure, so that the temperature of the acquisition unit is prevented from rising due to direct solar radiation, and the influence of the temperature on current measurement is avoided; the sun shade is provided with the blind window so that the inside and the outside of the sun shade can realize heat convection, the temperature of the acquisition unit is maintained to be stable, the light intensity stability of the light source of the acquisition unit and the polarization state stability of the light are ensured, and therefore the influence of the temperature on the measurement precision of the optical current transformer is further eliminated.
Drawings
Fig. 1 is a schematic structural diagram of an optical current transformer according to the present invention;
fig. 2 is a schematic structural view of a sensor head assembly of the present invention;
fig. 3 is a schematic structural view of the cover plate of the present invention;
fig. 4 is a schematic structural view of the flexible connecting member of the present invention;
fig. 5 is a schematic structural view of the collecting unit, the local cabinet body and the sunshade cover of the present invention.
Detailed Description
In order that the present invention may be more readily and clearly understood, the following detailed description of the present invention is provided in connection with the accompanying drawings.
As shown in fig. 1 to 4, an optical current transformer includes a sensing head assembly 1 and an insulator 2, where the sensing head assembly 1 includes a sensing head housing 3, an optical sensing ring assembly 4, and at least one flexible connecting part 5; wherein the content of the first and second substances,
the sensing head shell 3 is connected to the upper end part of the insulator 2;
a conductor channel 6 for passing through a conductor and an annular groove 7 arranged outside the conductor channel 6 are arranged in the sensing head shell 3;
the flexible connecting part 5 is connected to the sensor head shell 3 and is positioned in the annular groove 7;
the optical sensing ring assembly 4 is arranged in the annular groove 7, connected to the flexible connecting part 5 and used for sensing current in the conductor to generate an optical signal; specifically, the optical sensor ring assembly 4 is connected to the flexible connecting part 5, so that the optical sensor ring assembly 4 is not affected by vibration of the sensor head housing 3, interference of external vibration on optical signals generated by induction of the optical sensor ring assembly 4 is eliminated, and further influence of the external vibration on current measurement accuracy is eliminated. In this embodiment, the insulator 2 may be a composite insulator, and the optical sensing ring assembly 4 may be, but is not limited to, an optical fiber ring, which is well known to those skilled in the art and is not described in detail in this embodiment.
As shown in FIGS. 1-3, the sensor head housing 3 includes, for example, but not limited to, a housing body 8 and a cover plate 9; wherein the content of the first and second substances,
the shell body 8 is provided with an inner annular wall 10, an outer annular wall 11 and an end wall 12, the inner periphery of the end wall 12 is connected with the inner annular wall 10, the outer periphery of the end wall 12 is connected with the outer annular wall 11, and the inner annular wall 10, the outer annular wall 11 and the end wall 12 surround at least one part of the ring groove 7;
the cover plate 9 is connected to the shell body 8 and used for sealing the annular groove 7, and one end part of the cover plate 9 close to the shell body 8 is provided with an inner annular surface 13 used for being abutted with the end surface of the inner annular wall 10 and an outer annular surface 14 used for being abutted with the end surface of the outer annular wall 11;
the conductor channel 6 penetrates through the housing body 8 and the cover plate 9; in particular, the conductor channel 6 passes from the inside of the inner annular wall 10.
As shown in fig. 3, at least one of the inner annular surface 13 and the outer annular surface 14 is provided with an insulating oxide layer; in this embodiment, no insulating oxide layer is disposed on the outer annular surface 14, the outer annular surface 14 is electrically conducted with the outer annular wall 11, the inner annular surface 13 is disposed with the insulating oxide layer, and the inner annular surface 13 is insulated from the inner annular wall 10, so that a circulating current generated between the housing 8 and the cover plate 9 due to a current change in the conductor is effectively avoided, and an influence of the circulating current on a current measurement accuracy in the conductor is avoided. Specifically, the circulating current may flow into the optical sensing ring assembly 4, and the optical signal induced by the optical sensing ring assembly 4 may be inaccurate, thereby affecting the accuracy of the current measurement in the conductor.
As shown in fig. 2 and 3, an insulating oxide layer is disposed on an end surface of the cover plate 9 away from the housing 8, so as to prevent rainwater, electrolyte, and the like from forming a circulation channel between the outer end surface of the cover plate 9 and the housing 8, thereby preventing generation of a circulation current and preventing the circulation current from affecting the accuracy of current measurement. In this embodiment, the cover plate 9 may be made of an aluminum alloy, and the cover plate 9 may be anodized to generate the insulating oxide layer.
As shown in fig. 4, the flexible connecting part 5 is, for example and without limitation, a structure including a screw part 15, a flexible pad 16 and a screw hole part 17; wherein the content of the first and second substances,
the screw portion 15 is connected in the sensor head housing 3;
the flexible cushion 16 is connected to the screw part 15;
the threaded hole part 17 is embedded in the flexible cushion 16;
the optical sensing ring assembly 4 is connected to the flexible pad 16 by fasteners connected in the threaded hole parts 17; specifically, the fastening member may be a bolt, and the threaded hole part 17 is made of metal.
As shown in fig. 1 and 5, the optical current transformer may further include an acquisition unit 18 and an optical cable 19; wherein the content of the first and second substances,
one end of the optical cable 19 is connected with the acquisition unit 18, and the other end of the optical cable 19 is connected with the optical sensing ring assembly 4;
the acquisition unit 18 is used for receiving the optical signal generated by the optical sensing ring assembly 4 through the optical cable 19 and converting the optical signal into a digital quantity signal; specifically, the collecting unit 18 is configured to generate, modulate, and demodulate an optical signal so as to convert the optical signal into a digital signal, the collecting unit 18 may include a power module, a signal collecting board, and a light source box, the specific structure of the collecting unit 18 is a prior art well known to those skilled in the art, and details are not described in this embodiment; in this embodiment, the collecting unit 18 may be a current type collecting unit 18.
As shown in fig. 1 and 5, the insulator 2 may be attached to an external mounting frame 20, and the collecting unit 18 is mounted on the external mounting frame 20; specifically, in the conventional optical current transformer, the collection unit 18 is installed in a control room, which causes the insulator 2 to be far away from the collection unit 18, so that the length of the optical cable 19 is lengthened, which may cause damage to the optical signal during transmission in the optical cable 19. In this embodiment, the collection unit 18 is mounted on the external mounting frame 20 in a close manner, so that the length of the optical cable 19 can be shortened, the transmission distance of the optical signal can be shortened, the accuracy and precision of current measurement can be improved, and the influence of long-distance transmission of the optical signal can be avoided. In this embodiment, the collecting unit 18 is mounted on the external mounting bracket 20 near the low-voltage end of the insulator 2, where the low-voltage end of the insulator 2 is the lower end of the insulator 2; specifically, a merging unit is further installed in the control room, an input end of the merging unit is connected to the acquisition unit 18, a specific structure of the merging unit is the prior art, and details are not described in this embodiment.
As shown in fig. 1, the optical cable 19 extends from the lower end of the insulator 2 into the insulator 2 and passes through the insulator 2 to be connected to the optical sensing ring assembly 4.
As shown in fig. 5, the optical current transformer may further include a floor-standing cabinet body 21 and a sun shade 22; wherein the content of the first and second substances,
the acquisition unit 18 is arranged in the in-place cabinet box body 21;
the floor cabinet body 21 is arranged in the sunshade 22; specifically, the ground cabinet body 21 and the sun shade 22 form a double-layer structure, so that the temperature of the acquisition unit 18 is prevented from rising due to direct solar radiation, and the influence of the temperature on current measurement is avoided.
As shown in fig. 1 and 5, a louver 23 may be disposed on the sun shade 22, so that heat convection can be achieved between the inside and the outside of the sun shade 22, the temperature of the collecting unit 18 is maintained stable, and the light intensity and the polarization state of the light source of the collecting unit 18 are ensured to be stable, thereby further eliminating the influence of the temperature on the measurement accuracy of the optical current transformer.
Specifically, the local cabinet body 21 and the sun shade 22 can be sealed by adopting a foamed silica gel adhesive tape, so that the whole formed by the local cabinet body 21 and the sun shade 22 can realize the protection grade of IP67, and the outdoor protection and use requirements can be met.
The working principle of the utility model is as follows:
the optical sensing ring assembly 4 senses the current in the conductor to generate an optical signal, and the acquisition unit 18 receives the optical signal generated by the optical sensing ring assembly 4 through the optical cable 19 and converts the optical signal into a digital quantity signal so as to measure the magnitude of the current in the conductor. The optical sensing ring assembly 4 is connected to the flexible connecting part 5, so that the optical sensing ring assembly 4 is not affected by vibration of the sensing head shell 3, interference of external vibration on optical signals generated by sensing of the optical sensing ring assembly 4 is eliminated, and further influence of the external vibration on current measurement accuracy is eliminated.
At least one of the inner annular surface 13 and the outer annular surface 14 is provided with an insulating oxide layer, so that the circulation generated between the shell body 8 and the cover plate 9 due to the current change in the conductor can be effectively avoided, and the influence of the circulation on the current measurement precision in the conductor is avoided. The acquisition unit 18 is installed on the external mounting frame 20, and the length of the optical cable 19 can be shortened, so that the transmission distance of optical signals is shortened, the optical signals are prevented from being damaged in the transmission process in the optical cable 19, and the accuracy and precision of current measurement are improved. The ground cabinet body 21 and the sun shade 22 form a double-layer structure, so that the temperature of the acquisition unit 18 is prevented from being increased due to direct solar radiation, and the influence of the temperature on current measurement is avoided; the louver 23 is arranged on the sunshade 22, so that convection heat transfer can be realized inside and outside the sunshade 22, the temperature of the acquisition unit 18 is maintained to be stable, the light intensity stability of the light source of the acquisition unit 18 and the polarization state stability of the light are ensured, and the influence of the temperature on the measurement precision of the optical current transformer is further eliminated.
The above-mentioned embodiments further explain in detail the technical problems, technical solutions and advantages solved by the present invention, and it should be understood that the above only is a specific embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.
In the description of the present invention, it is to be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the equipment or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the product of the present invention is used, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the present disclosure, unless otherwise expressly stated or limited, the first feature may comprise both the first and second features directly contacting each other, and also may comprise the first and second features not being directly contacting each other but being in contact with each other by means of further features between them. Also, the first feature being above, on or above the second feature includes the first feature being directly above and obliquely above the second feature, or merely means that the first feature is at a higher level than the second feature. A first feature that underlies, and underlies a second feature includes a first feature that is directly under and obliquely under a second feature, or simply means that the first feature is at a lesser level than the second feature.
Claims (10)
1. An optical current transformer is characterized by comprising a sensing head assembly (1) and an insulator (2), wherein the sensing head assembly (1) comprises a sensing head shell (3), an optical sensing ring assembly (4) and at least one flexible connecting part (5); wherein the content of the first and second substances,
the sensing head shell (3) is connected to the upper end part of the insulator (2);
a conductor channel (6) for passing through a conductor and a ring groove (7) arranged on the outer side of the conductor channel (6) are arranged in the sensing head shell (3);
the flexible connecting part (5) is connected to the sensing head shell (3) and is positioned in the annular groove (7);
the optical sensing ring assembly (4) is installed in the annular groove (7), connected to the flexible connecting part (5) and used for sensing current in the conductor to generate an optical signal.
2. The optical current transformer of claim 1, wherein the sensor head housing (3) comprises a housing body (8) and a cover plate (9); wherein the content of the first and second substances,
an inner annular wall (10), an outer annular wall (11) and an end wall (12) are arranged in the shell body (8), the inner peripheral part of the end wall (12) is connected with the inner annular wall (10), the outer peripheral part of the end wall (12) is connected with the outer annular wall (11), and the inner annular wall (10), the outer annular wall (11) and the end wall (12) surround at least one part of the annular groove (7);
the cover plate (9) is connected to the shell body (8) and used for sealing the annular groove (7), and an inner annular surface (13) used for being abutted against the end surface of the inner annular wall (10) and an outer annular surface (14) used for being abutted against the end surface of the outer annular wall (11) are arranged at one end part, close to the shell body (8), of the cover plate (9);
the conductor channel (6) extends through the housing body (8) and the cover plate (9).
3. Optical current transformer according to claim 2, characterized in that at least one of the inner annular surface (13) and the outer annular surface (14) is provided with an insulating oxide layer and/or that the end surface of the cover plate (9) facing away from the housing body (8) is provided with an insulating oxide layer.
4. The optical current transformer according to claim 1, characterized in that the flexible connection member (5) comprises a screw portion (15), a flexible pad (16) and a threaded hole member (17); wherein the content of the first and second substances,
the screw part (15) is connected in the sensing head shell (3);
the flexible pad (16) is connected to the screw part (15);
the threaded hole part (17) is embedded in the flexible pad (16);
the optical sensing ring assembly (4) is connected to the flexible pad (16) by fasteners connected in the threaded hole parts (17).
5. Optical current transformer according to claim 1, characterized in that it further comprises a collection unit (18) and an optical cable (19); wherein the content of the first and second substances,
one end of the optical cable (19) is connected with the acquisition unit (18), and the other end of the optical cable (19) is connected with the optical sensing ring assembly (4);
the acquisition unit (18) is used for receiving the optical signal generated by the optical sensing ring assembly (4) through the optical cable (19) and converting the optical signal into a digital quantity signal.
6. Optical current transformer according to claim 5, characterized in that the insulator (2) is attached to an external mounting (20), the pick-up unit (18) also being mounted close to the external mounting (20).
7. Optical current transformer according to claim 5, characterized in that said optical cable (19) extends from the lower end of said insulator (2) into said insulator (2) and through said insulator (2) to be connected to said optical sensing ring assembly (4).
8. The optical current transformer of claim 5, further comprising a floor-standing cabinet body (21) and a sun shade (22); wherein the content of the first and second substances,
the acquisition unit (18) is arranged in the in-place cabinet box body (21);
the floor cabinet body (21) is arranged in the sunshade (22).
9. Optical current transformer according to claim 8, characterized in that a louver (23) is provided on the sun shield (22).
10. The optical current transformer according to claim 8, characterized in that the floor cabinet body (21) and/or the sun shade (22) are sealed with a foamed silicone rubber strip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021388717.5U CN213398694U (en) | 2020-07-15 | 2020-07-15 | Optical current transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021388717.5U CN213398694U (en) | 2020-07-15 | 2020-07-15 | Optical current transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213398694U true CN213398694U (en) | 2021-06-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021388717.5U Active CN213398694U (en) | 2020-07-15 | 2020-07-15 | Optical current transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213398694U (en) |
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- 2020-07-15 CN CN202021388717.5U patent/CN213398694U/en active Active
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