Flexible opening and closing type fixed magnetic shielding current measuring device and measuring method

Abstract

The invention provides a flexible opening and closing type fixed magnetic shielding current measuring device and a measuring method. The measuring device comprises an opening and closing type shielding shell which is of an annular structure; the conductor clamping mechanism is arranged at a central hole position of the opening and closing type shielding shell; the flexible Rogowski coil is detachably arranged in an inner cavity of the opening and closing type shielding shell, and a coil clamping assembly is arranged in the inner cavity of the opening and closing type shielding shell. The influence of an external interference magnetic field on the measurement precision of the flexible Rogowski coil can be greatly weakened, the measured current can be ensured to vertically pass through the skeleton plane center of the Rogowski coil, the influence of the position deviation of the measured current on the measurement precision of the flexible Rogowski coil is effectively reduced, the installation and the disassembly are convenient, the use flexibility can be greatly improved, and the measurement precision of the flexible Rogowski coil is improved. The influence of the position deviation of the measured current and an external interference magnetic field on the measurement precision of the flexible Rogowski coil is reduced, and the stability and the flexibility of measurement are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of current monitoring and metering, and in particular to a flexible opening and closing fixed magnetic shielding current measuring device and a measuring method. Background Art

[0002] As an important power equipment in the field of current monitoring and metering, Rogowski coil has the advantages of high measurement accuracy, wide measurement range, wide bandwidth, sensitive response, non-contact, small size, low cost, fast response, etc. It is easy to communicate with computers and is widely used to monitor large pulse currents, medium and low frequency periodic currents, transient currents, rapidly changing currents, harmonic currents in different industrial environments, and for power system relay protection. However, most Rogowski coils work in an environment where strong and weak current devices operate together. The electromagnetic environment is extremely complex and is easily affected by external interference magnetic fields during the measurement process. In addition, in actual current measurement, the measured current will not always be perpendicular to the center of the plane of the Rogowski coil skeleton. Due to installation or vibration and other reasons, the position of the measured current will deviate. Especially for flexible Rogowski coils, the position deviation of the measured current has a greater impact on its measurement accuracy. Therefore, how to eliminate or reduce the influence of external interference magnetic fields and the position deviation of the measured current on the measurement accuracy of the Rogowski coil has become a crucial issue.

[0003] Flexible Rogowski coils have the characteristics of small size, simple structure, low price, bendability, openability, and installation in complex environments such as narrow spaces. They are widely used in monitoring pulsed large currents in high-voltage transmission lines, current measurement of various power equipment and power electronic devices, and current monitoring of high-power electric locomotives in railway systems. They are the most widely used Rogowski coils in power systems.

[0004] However, in actual current monitoring and measurement, the flexible Rogowski coil is greatly affected by the position deviation of the measured current and the external interference magnetic field, and the measurement accuracy and stability are relatively low. The current method of reducing the external interference magnetic field is to place the working Rogowski coil in a grounded magnetic shielding box to shield the external interference magnetic field. However, these magnetic shielding boxes can only shield the external interference magnetic field, and cannot eliminate or reduce the influence of the position deviation of the measured current on the measurement accuracy of the Rogowski coil. In addition, during use, it is necessary to ensure that the measured current passes through the through hole of the magnetic shielding box, and online detection and measurement cannot be achieved. Summary of the invention

[0005] In view of this, the present invention proposes a flexible opening and closing fixed magnetic shielding current measuring device and measuring method, aiming to solve the problem that the existing flexible Rogowski coil is greatly affected by the position deviation of the measured current and the external interference magnetic field, resulting in relatively low measurement accuracy and stability.

[0006] On the one hand, the present invention proposes a flexible open-close fixed magnetic shielding current measuring device, which includes: an open-close shielding shell in an annular structure, which is used to be opened to be installed and sleeved on the outer periphery of the conductor to be measured; a conductor clamping mechanism, which is arranged at the central hole position of the open-close shielding shell, and is used to clamp the conductor to be measured, so that the measured current on the conductor to be measured passes vertically through the open-close shielding shell and is fixed at the center position of the open-close shielding shell; a flexible Rogowski coil, which is arranged in the inner cavity of the open-close shielding shell in a detachable manner, and a coil clamping assembly is provided in the inner cavity of the open-close shielding shell, and the flexible Rogowski coil is used to be opened to be installed on the outer periphery of the conductor to be measured, and can be closed and installed in the inner cavity of the open-close shielding shell to perform induction detection on the magnetic field generated by the measured current on the conductor to be measured, thereby obtaining the current magnitude of the measured current.

[0007] Furthermore, in the above-mentioned flexible open-and-close fixed magnetic shielding current measuring device, the conductor clamping mechanism and / or the coil clamping mechanism includes: a conductor clamping assembly for clamping the conductor to be measured or a flexible Rogowski coil; a connecting rod, one end of which is connected to the conductor clamping assembly and the other end is connected to the open-and-close shielding shell.

[0008] Furthermore, in the above-mentioned flexible open-and-close fixed magnetic shielding current measuring device, the conductor clamping assembly includes: two arc-shaped clamping arms, one ends of the two arc-shaped clamping arms are connected in a rotatable manner, the opening between the other ends of the two arc-shaped clamping arms can be opened to be installed on the periphery of the conductor to be measured or the flexible Rogowski coil, and the opening between the other ends of the two arc-shaped clamping arms can also be closed or reduced to clamp and fix on the outer peripheral wall of the conductor to be measured or the flexible Rogowski coil; an elastic reset member is arranged between the two arc-shaped clamping arms, and is used to elastically deform when the opening between the two arc-shaped clamping arms is opened to apply a reset force to the two arc-shaped clamping arms so that the two arc-shaped clamping arms can be reset to a closed state.

[0009] Furthermore, in the above-mentioned flexible opening and closing fixed magnetic shielding current measuring device, a serrated structure is provided on the inner wall of the arc-shaped clamping arm.

[0010] Furthermore, in the above-mentioned flexible opening and closing fixed magnetic shielding current measuring device, the connecting rod is a telescopic rod structure.

[0011] Furthermore, in the above-mentioned flexible open-and-close fixed magnetic shielding current measuring device, the open-and-close shielding shell comprises: two arc-shaped shielding shells; wherein, the two arc-shaped shielding shells are arranged opposite to each other, and one end of the two arc-shaped shielding shells arranged opposite to each other are butt-jointed and connected in a detachable manner, and a magnetic resistance gap is provided between the other ends of the two arc-shaped shielding shells arranged opposite to each other, which is used to prevent the two arc-shaped shielding shells from forming a loop, so as to prevent the generation of bypass magnetic flux.

[0012] Furthermore, in the above-mentioned flexible opening and closing fixed magnetic shielding current measuring device, the arc-shaped shielding shell body includes: an arc-shaped shielding shell body; an arc-shaped shielding upper cover, which is detachably fastened to the top of the arc-shaped shell body, and a detection gap is formed between the inner circumferential wall of the arc-shaped shielding shell body and the arc-shaped shielding upper cover, and the magnetic field generated by the measured current can pass through the detection gap and enter the interior of the arc-shaped shielding shell body and the arc-shaped shielding upper cover.

[0013] Furthermore, in the above-mentioned flexible openable fixed magnetic shielding current measuring device, a detection slot is provided on the inner peripheral wall of the openable shielding shell, so that the magnetic field generated by the measured current on the measured conductor can enter the inner cavity of the openable shielding shell through the detection slot.

[0014] Furthermore, in the above-mentioned flexible open-and-close fixed magnetic shielding current measuring device, a cable outlet hole is provided on the outer peripheral wall of the open-and-close shielding shell, and the output cable on the flexible Rogowski coil can extend from the cable outlet hole to the outside of the open-and-close shielding shell to output the induced electromotive force sensed by the flexible Rogowski coil, and then obtain the current magnitude of the measured current based on the induced electromotive force.

[0015] On the other hand, the present invention proposes a flexible open-close fixed magnetic shielding current measurement method, which uses a flexible open-close fixed magnetic shielding current measurement device to measure current. The measurement method includes the following steps: opening the open-close shielding shell of the measurement device and placing it on the periphery of the conductor to be measured, so that the conductor to be measured is placed at the center hole of the open-close shielding shell; disconnecting the flexible Rogowski coil of the measurement device and placing it in the inner cavity of the open-close shielding shell, clamping the flexible Rogowski coil by the coil clamping assembly, so that the flexible Rogowski coil is sleeved and fixed on the periphery of the conductor to be measured; connecting the interface of the flexible Rogowski coil to form a closed ring, and closing the open-close shielding shell; clamping the conductor to be measured by the conductor clamping mechanism of the measurement device, so that the measured current on the conductor to be measured passes vertically through the center position of the open-close shielding shell, so as to complete the installation between the measurement device and the conductor to be measured; after the installation between the measurement device and the conductor to be measured is completed, the open-close shielding shell is grounded, and the current measurement of the measured current on the conductor to be measured is performed by the measurement device.

[0016] The flexible open-close fixed magnetic shielding current measuring device and measuring method provided by the present invention can not only greatly weaken the influence of the external interference magnetic field on the measurement accuracy of the flexible Rogowski coil, but also ensure that the measured current passes vertically through the center of the skeleton plane of the Rogowski coil, effectively reducing the influence of the measured current position deviation on the measurement accuracy of the flexible Rogowski coil. At the same time, the open-close design of the open-close shielding shell and the detachable connection of the flexible Rogowski coil do not need to ensure that the measured current passes through the through hole of the measuring device during use. Through the opening and closing of the open-close shielding shell and the detachment of the flexible Rogowski coil, it can be directly installed to the periphery of the conductor to be measured, which is convenient for installation and disassembly, and can greatly improve the flexibility of use, reduce the influence of the measured current position deviation and the external interference magnetic field on the measurement accuracy of the flexible Rogowski coil, and improve the stability and flexibility of the measurement, and solve the problem that the existing flexible Rogowski coil is greatly affected by the measured current position deviation and the external interference magnetic field, resulting in relatively low measurement accuracy and stability. Therefore, the device can achieve high-precision current measurement, with relatively high accuracy, and can be measured online and can also be disassembled. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 A schematic diagram of the structure of a flexible opening and closing fixed magnetic shielding current measuring device provided in an embodiment of the present invention; Figure 2 A schematic diagram of the structure of the flexible retractable fixed magnetic shielding current measuring device provided in an embodiment of the present invention after the retractable shielding shell is opened; Figure 3 A schematic structural diagram of a flexible Rogowski coil connected and closed to form a ring and an open-and-closed shielding shell closed in a flexible open-and-closed fixed magnetic shielding current measuring device provided by an embodiment of the present invention; Figure 4 A schematic diagram of the structure of a flexible opening and closing fixed magnetic shielding current measuring device provided in an embodiment of the present invention after installation; Figure 5 A schematic structural diagram of a conductor clamping mechanism provided by an embodiment of the present invention; Figure 6 A schematic structural diagram of a coil clamping mechanism provided by an embodiment of the present invention; Figure 7 A flowchart of a flexible opening and closing fixed magnetic shielding current measurement method provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0019] Measuring device: See also Figures 1 to 4 , which shows the preferred structure of the flexible open-close fixed magnetic shielding current measuring device provided by the embodiment of the present invention. As shown in the figure, the measuring device includes: an open-close shielding shell 1, a conductor clamping mechanism 2, a flexible Rogowski coil 3 and a coil clamping assembly 4.

[0020] The open-close shielding shell 1 is an annular structure, which is used to be opened for installation and sleeved on the outer periphery of the conductor 5 to be measured. Specifically, the open-close shielding shell 1 is an annular structure, and the open-close shielding shell 1 is an open-close structure, which has an open and closed state. When the open-close shielding shell 1 is in the open state, the open-close shielding shell 1 can be sleeved on the conductor 5 to be measured from one side of the conductor 5 to be measured, so that the conductor 5 to be measured can be placed in the central hole of the open-close shielding shell 1. At the same time, the flexible Rogowski coil 3 can be disconnected and installed in the inner cavity of the open-close shielding shell 1. After being installed in place, the interface of the flexible Rogowski coil 3 is connected to form a closed circular ring placed in the inner cavity of the open-close shielding shell 1, so that the open-close shielding shell 1 and the flexible Rogowski coil 3 are installed in place. Among them, the open-close shielding shell 1 can be made of Permalloy to improve the effect of the open-close shielding shell 1 in shielding external interference magnetic fields. Of course, other materials, such as iron plate structures, can also be used, as long as it is ensured that the open-close shielding shell 1 can perform external interference shielding, and there is no limitation on it in this embodiment. The measured conductor 5 can be a cable, etc., so as to measure the measured current thereon. In this embodiment, the retractable shielding shell 1 is grounded so that the measuring device can better shield the external interference magnetic field.

[0021] The conductor clamping mechanism 2 is arranged at the central hole position of the open-closed shielding shell 1, and is used to clamp the measured conductor 5, so that the measured current on the measured conductor 5 passes vertically through the open-closed shielding shell 1 and is fixed at the central position of the open-closed shielding shell 1. Specifically, the conductor clamping mechanism 2 is arranged at the central hole position of the open-closed shielding shell 1, and the conductor clamping mechanism 2 is connected to the open-closed shielding shell 1 to clamp the measured conductor 5 placed in the central hole position of the open-closed shielding shell 1, so that the device can be fixedly clamped to the measured conductor 5. In this embodiment, there are two conductor clamping mechanisms 2, and the two conductor clamping mechanisms 2 are arranged opposite to each other to clamp the measured conductor 5 on both sides through opposite ends. Preferably, the two conductor clamping mechanisms 2 can be arranged along the same radial direction of the open-closed shielding shell 1.

[0022] The flexible Rogowski coil 3 is detachably arranged in the inner cavity of the open-closed shielding shell 1, and a coil clamping assembly 4 is provided in the inner cavity of the open-closed shielding shell 1. The flexible Rogowski coil 3 is used to be opened to be installed on the outer periphery of the measured conductor 5, and can be closed and installed in the inner cavity of the open-closed shielding shell 1 to perform induction detection on the magnetic field generated by the measured current on the measured conductor 5, thereby obtaining the current magnitude of the measured current. Specifically, the flexible Rogowski coil 3 is an open-closed structure, that is, its coil can be disconnected so that it can be installed in the inner cavity of the open-closed shielding shell 1, and after being installed in place, the interface connection forms a closed ring sleeved on the outer periphery of the measured conductor 5, so that the magnetic field generated by the measured current on the measured conductor 5 can enter the inner cavity of the open-closed shielding shell 1, so that the flexible Rogowski coil 3 can perform induction detection on the magnetic field, generate an induced electromotive force, and output it to an external signal processor through an output cable 31 on the flexible Rogowski coil 3 for data processing, thereby obtaining the current magnitude of the measured current. Among them, the arrangement of the coil clamping assembly 4 can realize the clamping and fixing of the flexible Rogowski coil 3, realize the fixing of the position of the flexible Rogowski coil 3, and thus prevent the flexible Rogowski coil 3 from moving due to vibration and other reasons; there are at least three coil clamping assemblies 4, which are arranged at intervals along the circumference of the open-close shielding shell to clamp and fix the flexible Rogowski coil 3 in a circular ring structure. In this embodiment, there are four coil clamping assemblies 4, and other numbers may also be used, which are not limited in this embodiment.

[0023] In this embodiment, a detection slit 11 is provided on the inner peripheral wall of the retractable shielding shell 1, so that the magnetic field generated by the measured current on the measured conductor 5 can enter the inner cavity of the retractable shielding shell 1 from the detection slit 11, that is, in order to allow the main magnetic flux generated by the measured current to smoothly enter the flexible Rogowski coil 3, so that the flexible Rogowski coil 3 can perform induction detection on the magnetic field generated by the measured current, thereby realizing the generation of the measured current. Specifically, the detection slit 11 can be arranged along the entire circumference of the retractable shielding shell 1.

[0024] In this embodiment, a cable outlet hole 12 is also provided on the outer peripheral wall of the retractable shielding shell 1, and the output cable 31 on the flexible Rogowski coil 3 can extend from the cable outlet hole 12 to the outside of the retractable shielding shell 1 to output the induced electromotive force sensed by the flexible Rogowski coil 3, and then obtain the current magnitude of the measured current based on the induced electromotive force. Specifically, the cable outlet hole 12 can be a circular through hole and can be adapted to the outer diameter of the output cable 31 to facilitate the outlet of the output cable 31.

[0025] Continue to see Figure 1The retractable shielding shell 1 may include: two arc-shaped shielding shells 13; wherein the two arc-shaped shielding shells 13 are arranged opposite to each other, and one end of the two arc-shaped shielding shells 13 arranged opposite to each other (such as Figure 1 The right end shown in the figure) is butted and connected in a detachable manner, and the other ends (as shown in the figure) of the two arc-shaped shielding shells 11 are arranged opposite to each other. Figure 1 There is a magnetic resistance gap 14 between the two arc-shaped shielding shells 13 to prevent the two arc-shaped shielding shells 13 from forming a loop, so as to prevent the generation of bypass magnetic flux.

[0026] Specifically, the two arc-shaped shielding shells 13 can be arranged relative to each other, and one end can be connected by a connector (not shown in the figure) to enclose a ring structure with a gap, i.e., a magnetic resistance gap 14, so that it can be disassembled and then connected from both sides of the conductor 5 to be measured. The setting of the connector can control the opening and closing of the retractable shielding shell 1. The cross-sectional shape of the arc-shaped shielding shell 13 can be a nearly semicircular ring, and of course it can be other various arcs. It should be noted that the two arc-shaped shielding shells 13 can be arranged relative to each other and connected to form a ring structure with a gap, i.e., a magnetic resistance gap 14. In this embodiment, there is no limitation on its cross-sectional shape. In this embodiment, the magnetic resistance gap 14 can be 1-2mm. Of course, the two left ends of the two arc-shaped shielding shells 13 can also be connected and fixed by a connector, or can be a suspended end, and there is no limitation on it in this embodiment. Among them, the connector can be a bolt or other connector, and there is no limitation on it in this embodiment. In this embodiment, since the magnetic permeability of the open-close shielding shell 1 is much greater than the magnetic permeability of air, if there is no magnetic resistance gap 14, the magnetic field generated by the measured current will be concentrated in the open-close shielding shell 1, and will not enter the interior of the flexible Rogowski coil 3. The setting of the magnetic resistance gap 14 in this embodiment makes it impossible for the open-close shielding shell 1 to form a loop, and the magnetic resistance becomes very large, so that the magnetic flux can enter the flexible Rogowski coil 3 in the open-close shielding shell 1. Therefore, the setting of the magnetic resistance gap 14 can prevent the measuring device from generating bypass magnetic flux during use. In this embodiment, the cable outlet hole 12 is set on the outer peripheral wall of one of the arc-shaped shielding shells 13. The two arc-shaped shielding shells 13 are butt-jointed so as to be fitted around the outer periphery of the conductor 5 to be measured.

[0027] Continue to see Figure 1 The arc-shaped shielding shell body 13 includes: an arc-shaped shielding shell body 131 and an arc-shaped shielding upper cover 132; wherein the arc-shaped shielding upper cover 132 is detachably fastened to the top of the arc-shaped shell body 131, and a detection gap 14 is formed between the inner circumferential wall of the arc-shaped shielding shell body 131 and the arc-shaped shielding upper cover 132, and the magnetic field generated by the measured current can pass through the detection gap 14 and enter the interior of the arc-shaped shielding shell body 131 and the arc-shaped shielding upper cover 132.

[0028] Specifically, the arc-shaped shielding shell body 131 can be made of Permalloy, which includes an arc-shaped bottom plate, an outer peripheral side plate arranged on the outer edge of the arc-shaped bottom plate and extending vertically, and a lower inner peripheral side plate arranged on the inner edge of the arc-shaped bottom plate and extending vertically, wherein the outer peripheral side plate serves as the outer peripheral wall of the retractable shielding shell 1, and the arc-shaped bottom plate, the outer peripheral side plate and the lower inner peripheral side plate can be an integral structure. The arc-shaped shielding upper cover 132 includes: an arc-shaped upper cover adapted to the arc-shaped bottom plate and an upper inner peripheral side plate arranged on the inner edge of the arc-shaped upper cover and extending vertically, wherein when the arc-shaped shielding upper cover 132 is covered on the arc-shaped shielding shell body 131, a detection gap 14 is formed between the lower inner peripheral side plate and the upper inner peripheral side plate, and the lower inner peripheral side plate and the upper inner peripheral side plate are combined to form the inner peripheral wall of the retractable shielding shell 1; wherein the arc-shaped upper cover and the lower inner peripheral side plate can be an integral structure. In this embodiment, the arc-shaped shielding shell body 131 and the arc-shaped shielding upper cover 132 can be connected via a connecting piece so as to be assembled and disassembled before and after the flexible Rogowski coil 3 is installed, so as to install the flexible Rogowski coil 3 .

[0029] See also Figure 5 , which is a schematic diagram of the structure of the conductor clamping mechanism provided by an embodiment of the present invention. As shown in the figure, the conductor clamping mechanism 2 includes: a conductor clamping assembly 21 and a connecting rod 22; wherein the conductor clamping assembly 21 is used to clamp the conductor 5 to be measured; one end of the connecting rod 22 (such as Figure 5 The left end as shown in FIG. 1 is connected to the conductor clamping assembly 21, and the other end (as shown in FIG. Figure 1 The upper end of the upper conductor clamping mechanism 2 shown in the figure is connected to the retractable shielding shell 1 to support and fix the conductor clamping assembly 21.

[0030] Specifically, the fixed end of the conductor clamping assembly 21 can be fixedly mounted on the connecting rod 22, so as to be supported on the outer peripheral wall of the open-close shielding shell 1 through the connecting rod 22, so that the conductor clamping assembly 21 can be supported in the central hole of the open-close shielding shell 1, and then clamp the conductor 5 to be measured. In this embodiment, the connecting rod 22 can be a telescopic rod structure, which is used to adjust the clamping position of the conductor clamping assembly 21 to adapt to the conductor 5 to be measured with different outer diameters, that is, the position of the two conductor clamping assemblies 21 is adjusted by the two connecting rods 22 in the central hole of the open-close shielding shell 1, and then the conductor 5 to be measured with different outer diameters is clamped on both sides.

[0031] Continue to see Figure 5 The conductor clamping assembly 21 includes: two arc-shaped clamping arms 211 and an elastic reset member (not shown in the figure); wherein one end of the two arc-shaped clamping arms 211 (such as Figure 5 The other ends of the two arc-shaped clamping arms 211 (as shown in the right end) are connected in a rotatable manner, and the other ends of the two arc-shaped clamping arms 211 (as shown in the right end) are connected in a rotatable manner. Figure 5The opening between the two arc-shaped clamping arms 211 (left end shown in the figure) can be opened to be installed on the periphery of the conductor 5 to be measured, and the opening between the other ends of the two arc-shaped clamping arms 211 can also be closed or reduced to be clamped and fixed on the peripheral wall of the conductor 5 to be measured; an elastic reset member (not shown in the figure) is arranged between the two arc-shaped clamping arms 211, and is used for elastically deforming when the opening between the two arc-shaped clamping arms 211 is opened, so as to apply a reset force to the two arc-shaped clamping arms 211, so that the two arc-shaped clamping arms 211 can be reset to a closed state.

[0032] Specifically, one end of the two arc-shaped clamping arms 211 (such as Figure 5 The two arc-shaped clamping arms 211 are connected in a rotatable manner, for example, they can be rotatably connected by a pin shaft, so that the angle between the two arc-shaped clamping arms 211 can be adjusted, so that the two arc-shaped clamping arms 211 can be relatively opened or closed. When the two arc-shaped clamping arms 211 are opened, the openings at the other ends of the two arc-shaped clamping arms 211 become larger, that is, the spacing becomes larger, so that they can be clamped to the outer wall of the conductor to be measured. Of course, when the two arc-shaped clamping arms 211 are closed, the openings at the other ends of the two arc-shaped clamping arms 211 become smaller, that is, the spacing becomes smaller, or the other ends of the two arc-shaped clamping arms 211 are closed without openings, so that they can be clamped to the outer wall of the conductor to be measured. The elastic reset member may be a torsion spring, and both ends are respectively connected to the two arc-shaped clamping arms 211, so as to be elastically deformed when the two arc-shaped clamping arms 211 are opened, and when the two arc-shaped clamping arms 211 are in a free state, the two arc-shaped clamping arms 211 can be reset and closed under the reset action of the elastic reset member, thereby clamping the conductor 5 to be measured. The inner walls of the two arc-shaped clamping arms 211 may be provided with a serrated structure to improve the stability of clamping the conductor 5 to be measured.

[0033] In this embodiment, in order to adapt to the clamping of the conductor 5 under test with different outer diameters, preferably, the connecting rod 22 can be a telescopic rod structure, which is used to adjust the clamping position of the conductor clamping assembly 21 to adapt to the conductor 5 under test with different outer diameters, thereby expanding the application range of the device.

[0034] See also Figure 6 , which is a schematic diagram of the structure of the coil clamping mechanism provided by an embodiment of the present invention. As shown in the figure, the structure of the coil clamping mechanism 4 can refer to the structure of the conductor clamping mechanism 2, and the structures of the two can refer to each other.

[0035] In summary, the flexible open-close fixed magnetic shielding current measuring device provided in this embodiment can not only greatly weaken the influence of the external interference magnetic field on the measurement accuracy of the flexible Rogowski coil, but also ensure that the measured current passes vertically through the center of the skeleton plane of the Rogowski coil, effectively reducing the influence of the measured current position deviation on the measurement accuracy of the flexible Rogowski coil. At the same time, the open-close design of the open-close shielding shell and the detachable connection of the flexible Rogowski coil do not need to ensure that the measured current passes through the through hole of the measuring device during use. Through the opening and closing of the open-close shielding shell and the detachment of the flexible Rogowski coil, it can be directly installed to the periphery of the conductor to be measured, which is convenient for installation and disassembly, and can greatly improve the flexibility of use, reduce the influence of the measured current position deviation and the external interference magnetic field on the measurement accuracy of the flexible Rogowski coil, and improve the stability and flexibility of the measurement, and solve the problem that the existing flexible Rogowski coil is greatly affected by the measured current position deviation and the external interference magnetic field, resulting in relatively low measurement accuracy and stability. Therefore, the device can achieve high-precision current measurement with relatively high accuracy, and can be measured online and can also be disassembled.

[0036] Method Example: See also Figure 7 , which is a flowchart of a flexible opening and closing fixed magnetic shielding current measurement method provided by an embodiment of the present invention. The measurement method uses the above-mentioned flexible opening and closing fixed magnetic shielding current measurement device to measure the measured current on the measured conductor 5. As shown in the figure, the measurement method includes the following steps: Step S1, opening the retractable shielding shell of the measuring device and placing it on the periphery of the conductor to be measured, so that the conductor to be measured is placed at the center hole of the retractable shielding shell.

[0037] Specifically, first, loosen the connector between the two arc-shaped shielding shells 13 and open the two arc-shaped shielding shells 13; then, place the two arc-shaped shielding shells 13 around the conductor 5 to be measured so that the conductor 5 to be measured is located at the central through hole of the measuring device, that is, the central hole surrounded by the two arc-shaped shielding shells 13.

[0038] Step S2, disconnecting the flexible Rogowski coil of the measuring device and placing it into the inner cavity of the open-close shielding shell.

[0039] Specifically, first, loosen the connecting piece between the arc-shaped shielding shell body 131 and the arc-shaped shielding upper cover 132 in the two arc-shaped shielding shells 13, and open the arc-shaped shielding upper cover 132 in the two arc-shaped shielding shells 13; then, put the flexible Rogowski coil 3 into the inner cavity of the measuring device, that is, the inner cavity enclosed between the arc-shaped shielding shell body 131 and the arc-shaped shielding upper cover 132, as shown in FIG. Figure 2 shown.

[0040] Step S3, connecting the interfaces of the flexible Rogowski coil to form a closed ring, clamping the flexible Rogowski coil through the coil clamping assembly, and closing the open-close shielding shell so that the flexible Rogowski coil is fixed on the periphery of the conductor to be measured, and the open-close shielding shell is closed and arranged outside the flexible Rogowski coil.

[0041] Specifically, first, tighten the connector between the two arc-shaped shielding shells 13, close the two arc-shaped shielding shells 13, that is, the right ends of the two arc-shaped shielding shells 13 are butted, and the left ends have a magnetic resistance gap 14, forming an integrated ring structure, that is, the two arc-shaped shielding shell bodies 131 of the two arc-shaped shielding shells 13 are butted to form a bottom ring structure. And connect the interface of the flexible Rogowski coil 3 to form a closed ring, and then open the coil clamping mechanism 4, that is, open the two arc-shaped clamping arms 211 of the coil clamping mechanism 4, and place the flexible Rogowski coil 3 between the two arc-shaped clamping arms 211, loosen the two arc-shaped clamping arms 211, and the elastic reset member controls the two arc-shaped clamping arms 211 to close, thereby fixing the flexible Rogowski coil 3 on the coil clamping mechanism 4. Then, the output cable 31 of the flexible Rogowski coil 3 is passed through the cable outlet hole 12, and the connectors of the two arc-shaped shielding upper covers 132 are locked, and the two arc-shaped shielding upper covers 132 are closed, so that the two arc-shaped shielding upper covers 132 are fixed to the two arc-shaped shielding shell bodies 131, as shown in FIG. Figure 3 shown.

[0042] Step S4, clamping the conductor to be measured by the conductor clamping mechanism of the measuring device, so that the measured current on the conductor to be measured passes vertically through the center position of the open-close shielding shell, thereby completing the installation between the measuring device and the conductor to be measured.

[0043] Specifically, first, the connecting rod 22 of the conductor clamping mechanism 2 is retracted to leave enough installation space for the conductor 5 to be measured. Then, the conductor 5 to be measured is placed in the center of the through hole, and the conductor clamping mechanism 2 is opened, that is, the two arc-shaped clamping arms 211 of the conductor clamping mechanism 2 are opened. At the same time, the connecting rod is extended so that the inner side walls of the arc-shaped clamping arms 211 are tightly attached to the conductor 5 to be measured. The two arc-shaped clamping arms 211 are loosened, and the elastic reset member controls the two arc-shaped clamping arms 211 to close, thereby fixing the conductor to be measured on the conductor clamping mechanism 2. Figure 4 shown.

[0044] Step S5, after the measuring device is installed between the conductor to be measured, the retractable shielding shell is grounded, and the current to be measured on the conductor to be measured is measured by the measuring device.

[0045] Specifically, after the flexible Rogowski coil 3 and the measured conductor 5 are installed, the retractable shielding shell 1 is grounded; and the measured current on the measured conductor is measured by a measuring device.

[0046] In summary, the flexible open-and-close fixed magnetic shielding current measurement method provided in this embodiment can not only greatly weaken the influence of the external interference magnetic field on the measurement accuracy of the flexible Rogowski coil, but also ensure that the measured current passes vertically through the center of the skeleton plane of the Rogowski coil, effectively reducing the influence of the measured current position deviation on the measurement accuracy of the flexible Rogowski coil. At the same time, the open-and-close design of the open-and-close shielding shell and the detachable connection of the flexible Rogowski coil do not need to ensure that the measured current passes through the through hole of the measuring device during use. Through the opening and closing of the open-and-close shielding shell and the detachment of the flexible Rogowski coil, it can be directly installed to the periphery of the conductor to be measured, which is convenient for installation and disassembly, and can greatly improve the flexibility of use, reduce the influence of the measured current position deviation and the external interference magnetic field on the measurement accuracy of the flexible Rogowski coil, and improve the stability and flexibility of the measurement, and solve the problem that the existing flexible Rogowski coil is greatly affected by the measured current position deviation and the external interference magnetic field, resulting in relatively low measurement accuracy and stability.

[0047] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0048] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A flexible opening and closing fixed magnetic shielding current measuring device, characterized in that: include: The retractable shielding shell is annular in structure and is used to be opened for installation and is sleeved on the outer periphery of the conductor to be measured; A conductor clamping mechanism, arranged at the central hole of the open-close shielding shell, for clamping the conductor to be measured, so that the measured current on the conductor to be measured passes vertically through the open-close shielding shell and is fixed at the central position of the open-close shielding shell; A flexible Rogowski coil is detachably arranged in the inner cavity of the open-close shielding shell, and a coil clamping assembly is provided in the inner cavity of the open-close shielding shell. The flexible Rogowski coil is used to be opened to be installed on the periphery of the conductor to be measured, and can be closed and installed in the inner cavity of the open-close shielding shell to perform induction detection on the magnetic field generated by the measured current on the conductor to be measured, thereby obtaining the current magnitude of the measured current.

2. The flexible opening and closing fixed magnetic shielding current measuring device according to claim 1 is characterized in that: The conductor clamping mechanism and / or the coil clamping mechanism comprises: Conductor clamping assembly, used to clamp the conductor to be measured or the flexible Rogowski coil; A connecting rod has one end connected to the conductor clamping assembly and the other end connected to the retractable shielding shell.

3. The flexible opening and closing fixed magnetic shielding current measuring device according to claim 2 is characterized in that: The conductor clamping assembly comprises: Two arc-shaped clamping arms, one ends of the two arc-shaped clamping arms are connected in a rotatable manner, the opening between the other ends of the two arc-shaped clamping arms can be opened to be installed on the periphery of the conductor to be measured or the flexible Rogowski coil, and the opening between the other ends of the two arc-shaped clamping arms can also be closed or reduced to clamp and fix on the peripheral wall of the conductor to be measured or the flexible Rogowski coil; The elastic reset member is arranged between the two arc-shaped clamping arms and is used for elastically deforming when the opening between the two arc-shaped clamping arms is opened to apply a reset force to the two arc-shaped clamping arms so that the two arc-shaped clamping arms can be reset to a closed state.

4. The flexible opening and closing fixed magnetic shielding current measuring device according to claim 3 is characterized in that: A sawtooth structure is provided on the inner wall of the arc-shaped clamping arm.

5. The flexible opening and closing fixed magnetic shielding current measuring device according to claim 2 is characterized in that: The connecting rod is a telescopic rod structure.

6. The flexible opening and closing fixed magnetic shielding current measuring device according to any one of claims 1 to 5, characterized in that: The retractable shielding shell comprises: two arc-shaped shielding shells; wherein, The two arc-shaped shielding shells are arranged opposite to each other, and one end of the two arc-shaped shielding shells are butt-jointed and connected in a detachable manner, and a magnetic resistance gap is provided between the other ends of the two arc-shaped shielding shells, which is used to prevent the two arc-shaped shielding shells from forming a loop, so as to prevent the generation of bypass magnetic flux.

7. The flexible opening and closing fixed magnetic shielding current measuring device according to claim 6 is characterized in that: The arc-shaped shielding shell comprises: Arc-shaped shielding shell body; The arc-shaped shielding upper cover is detachably fastened to the top of the arc-shaped shell body, and a detection gap is formed between the inner circumferential wall of the arc-shaped shielding shell body and the arc-shaped shielding upper cover. The magnetic field generated by the measured current can pass through the detection gap and enter the interior of the arc-shaped shielding shell body and the arc-shaped shielding upper cover.

8. The flexible opening and closing fixed magnetic shielding current measuring device according to any one of claims 1 to 5, characterized in that: A detection slot is provided on the inner peripheral wall of the retractable shielding shell, so that the magnetic field generated by the measured current on the measured conductor can enter the inner cavity of the retractable shielding shell through the detection slot.

9. The flexible opening and closing fixed magnetic shielding current measuring device according to any one of claims 1 to 5, characterized in that: A cable outlet hole is provided on the outer peripheral wall of the retractable shielding shell, and the output cable on the flexible Rogowski coil can extend from the cable outlet hole to the outside of the retractable shielding shell to output the induced electromotive force sensed by the flexible Rogowski coil, and then obtain the current magnitude of the measured current based on the induced electromotive force.

10. A flexible opening and closing fixed magnetic shielding current measurement method, characterized in that: The current is measured by using the flexible opening and closing fixed magnetic shielding current measuring device as described in any one of claims 1 to 9, and the measuring method comprises the following steps: Opening the retractable shielding shell of the measuring device and placing it on the periphery of the conductor to be measured, so that the conductor to be measured is placed at the center hole of the retractable shielding shell; The flexible Rogowski coil of the measuring device is disconnected and placed in the inner cavity of the retractable shielding shell, and the flexible Rogowski coil is clamped by the coil clamping assembly so that the flexible Rogowski coil is fixedly sleeved on the periphery of the conductor to be measured; Connecting the interfaces of the flexible Rogowski coil to form a closed ring, and closing the open-close shielding shell; The conductor to be measured is clamped by the conductor clamping mechanism of the measuring device, so that the measured current on the conductor to be measured passes vertically through the center position of the retractable shielding shell, so as to complete the installation between the measuring device and the conductor to be measured; After the measuring device is installed between the conductor to be measured, the retractable shielding shell is grounded, and the current to be measured on the conductor to be measured is measured by the measuring device.

Images