Current sensor of wind power plant on-line monitoring device

Abstract

The utility model discloses a current sensor of an on-line monitoring device of a wind power plant, comprising a framework which forms a diversion channel for a transmission wire of a to-be-measured current to pass through; the magnetic core is arranged in the framework, and the diversion channel penetrates through the magnetic core, so that a to-be-measured current generates an induced magnetic field under the action of electromagnetic induction; the coil is wound on the flow guide channel and is used for generating induced current under the action of an induced magnetic field; and the detection circuit is connected to the coil and is used for detecting the generated induction current. According to the technical scheme, the problem that the sensitivity is not high enough when the Rogowski coil measures small current is solved, and the sensitivity of the sensor for detecting the small current is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a current sensor for an online monitoring device of a wind farm. Background Art

[0002] As an important source of clean energy, wind farms have been widely developed and applied around the world. With the continuous advancement of technology and the reduction of costs, wind farms have become a competitive renewable energy generation method. However, due to the large number of branches of wind farm collector lines and the distance between branches is only about 100 meters, the transient current generated after the fault is more complicated in the folding and reflection at each branch point, making the attenuation of the fault current more serious.

[0003] Rogowski coils are usually designed to measure larger currents, and are increasingly used in monitoring transient currents on collector lines in wind power generation systems. However, when measuring small currents, their sensitivity is not high enough, and it is difficult to accurately measure weak current signals. Utility Model Content

[0004] The main purpose of the utility model is to provide a current sensor for an online monitoring device of a wind farm, aiming to solve the problem that the sensitivity of the Rogowski coil is not high enough when measuring small currents.

[0005] To achieve the above-mentioned purpose, the utility model provides a current sensor for an online monitoring device of a wind farm, comprising:

[0006] A frame, wherein the frame is formed with a flow-conducting channel for passing a transmission wire of a current to be measured;

[0007] A magnetic core, wherein the magnetic core is disposed in the frame, and the flow guide channel passes through the magnetic core, so that the current to be measured generates an induced magnetic field under the action of electromagnetic induction;

[0008] a coil, wound around the flow-conducting channel, and used to generate an induced current under the action of an induced magnetic field; and

[0009] A detection circuit is connected to the coil and is used to detect the generated induced current.

[0010] Optionally, the current sensor includes two magnetic cores, the two magnetic cores are arranged at intervals along the extension direction of the guide channel, and the guide channel passes through the two magnetic cores in sequence.

[0011] Optionally, the skeleton includes a first skeleton and a second skeleton, and the first skeleton and the second skeleton are spaced apart to form the guide channel.

[0012] Optionally, the magnetic core includes a first magnetic core and a second magnetic core that are spaced apart from each other, the first magnetic core is movably disposed in a first skeleton, and the second magnetic core is movably disposed in a second skeleton.

[0013] Optionally, the magnetic core includes two first magnetic cores, and the two first magnetic cores are rotatably arranged in the first skeleton so that cross sections of the two first magnetic cores are not in the same plane.

[0014] Optionally, the magnetic core includes two second magnetic cores, and the two second magnetic cores are rotatably arranged in the second skeleton so that cross sections of the two second magnetic cores are not in the same plane.

[0015] Optionally, the coil is wound with enameled wire.

[0016] In the technical solution of the utility model, when the conductor to be tested is inserted into the flow channel, according to the Ampere loop theorem, when the current flows in the conductor, a magnetic field surrounding the conductor is generated; the magnetic core arranged in the skeleton concentrates and conducts the generated magnetic field, and the generated magnetic field passes through the coil wound on the flow channel, thereby generating an induced electromotive force in the coil. When a fault occurs, the current changes, and the magnetic field also changes. According to Faraday's law of electromagnetic induction, when the magnetic field changes, an induced current will be generated around it. The generated induced current is detected through the detection circuit, thereby obtaining the current value to be measured; due to the provision of the magnetic core and the skeleton, the upper and lower limits of the current sensor for detecting the small current of the fault are expanded, so that the weak current on the conductor to be tested can be sensed, and the sensor is not easy to reach saturation. The technical solution of the utility model solves the problem of low detection sensitivity of the Rogowski coil for small current signals, and improves the sensitivity of the current sensor for detecting small currents. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0018] Figure 1 This is a schematic diagram of the structure of a current sensor in an embodiment of the utility model when it is opened;

[0019] Figure 2 This is a schematic diagram of the structure of a current sensor in a closed state according to an embodiment of the utility model;

[0020] Figure 3 This is a schematic diagram of the structure of two magnetic cores in a current sensor according to an embodiment of the utility model;

[0021] Figure 4 An exploded view of two magnetic cores in a current sensor according to an embodiment of the utility model;

[0022] Figure 5 A cutting plane diagram of a skeleton and a magnetic core of a current sensor according to an embodiment of the utility model;

[0023] Figure 6 This is a schematic diagram of the structure of the first frame and the second frame in the current sensor of one embodiment of the utility model;

[0024] Description of Figure Numbers:

[0025] Label name Label name 1 skeleton 32 Second magnetic core 11 The first skeleton 4 Coil 12 The second skeleton 5 Partition 2 Diversion channel 6 First baffle 3 Magnetic core 7 Second baffle 31 The first magnetic core 8 Connecting plate

[0026] The purpose, features and advantages of the present invention will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0029] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0030] Embodiment 1

[0031] See also Figures 1 to 6 As shown, in one embodiment of the utility model, a current sensor of a wind farm online monitoring device includes:

[0032] A skeleton 1, the skeleton is formed with a flow-conducting channel 2 for passing a transmission wire of a current to be measured;

[0033] A magnetic core 3 is arranged in the frame, and the flow guide channel 2 passes through the magnetic core 3, so that the current to be measured generates an induced magnetic field under the action of electromagnetic induction;

[0034] The coil 4 is wound around the flow guiding channel 2 and is used to generate an induced current under the action of an induced magnetic field; and

[0035] The detection circuit is connected to the coil winding 4 and is used to detect the generated induced current.

[0036] The technical solution of the utility model is that when the conductor to be tested is inserted into the flow channel 2, according to the Ampere loop theorem, when the current flows in the conductor, a magnetic field surrounding the conductor is generated; the magnetic core 3 arranged in the skeleton concentrates and conducts the generated magnetic field, and the generated magnetic field passes through the coil 4 wound on the flow channel 2, thereby generating an induced electromotive force in the coil 4. When a fault occurs, the current changes, and the magnetic field also changes. According to Faraday's law of electromagnetic induction, when the magnetic field changes, an induced current will be generated around, and the generated induced current is detected through the detection circuit, so as to obtain the current value to be measured; due to the provision of the magnetic core 3 and the skeleton 1, the upper and lower limits of the current sensor for detecting the small current of the fault are expanded, so the weak current on the conductor to be tested can be sensed, and the sensor is not easy to reach saturation. The technical solution of the utility model solves the problem of low detection sensitivity of the Rogowski coil for small current signals, and improves the sensitivity of the current sensor for detecting small currents. The upper and lower limits of the current sensor for detecting the small current of the fault are expanded, so the weak current on the conductor to be tested can be sensed, and the sensor is not easy to reach saturation. The technical solution of the utility model solves the problem that the detection sensitivity of the Rogowski coil to small current signals is low, and improves the measurement sensitivity of the current sensor to tiny currents.

[0037] Specifically, the skeleton 1 is formed with a flow guide channel 2 for passing the transmission wire of the current to be measured; in the present embodiment, the skeleton 1 is a hollow structure, and the hollow structure of the skeleton 1 does not contain the magnetic core 3, so it will not cause the problem of magnetic saturation, and to a certain extent, it can also show good restoration for measuring fault currents with larger amplitudes, making up for the magnetic saturation disadvantage of the single magnetic core; the magnetic core 3, the magnetic core 3 is arranged in the skeleton 1, and the flow guide channel 2 passes through the magnetic core 3, so that the current to be measured generates an induced magnetic field under the action of electromagnetic induction; the magnetic core 3 is sensitive to slight changes in the surrounding magnetic field, so it can respond well to fault currents with small amplitudes, but it is easy to cause magnetic saturation due to excessive current. Therefore, the utility model combines the hollow structure skeleton 1 and the magnetic core 3 for design, which can effectively increase the conductivity of the magnetic circuit. The magnetic core 3 can guide the propagation of the magnetic field. The hollow structure skeleton 1 can help extend the length of the magnetic circuit, thereby improving the conduction efficiency of the magnetic field; the magnetic core 3 can also concentrate the magnetic field lines and increase the sensitivity of the magnetic field induction, and the hollow structure skeleton 1 can help expand the sensing range, so that the sensor's sensing of the magnetic field is more comprehensive and accurate; and the distribution and propagation path of the magnetic field can be effectively controlled. This helps to reduce the problems of magnetic field leakage and external interference, and improve the measurement accuracy and stability of the sensor. The coil 4 is wound around the guide channel 2 and is used to generate an induced current under the action of the induced magnetic field; the detection circuit is connected to the coil 4 and is used to detect the generated induced current; the magnetic field generated by the conductor to be measured passes through the coil 4 wound around the guide channel 2, and an induced electromotive force is generated in the coil 4. When a fault occurs, the current changes and the magnetic field also changes. According to Faraday's law of electromagnetic induction, when the magnetic field changes, an induced current will be generated around it. The generated induced current is detected by the detection circuit, so as to obtain the current value to be measured and the detection circuit.

[0038] It can be seen from this that the hollow structure skeleton 1 and the magnetic core 3 are designed in combination, so that the sensor is not easy to reach magnetic saturation too early while monitoring small fault currents, and can well sense fault currents of smaller amplitudes, that is, expand its monitoring range of small fault currents, that is, the upper and lower limits of the sensor monitoring current.

[0039] Embodiment 2

[0040] See also Figures 1 to 6 As shown, on the basis of the first embodiment, the current sensor further comprises two magnetic cores 3, the two magnetic cores 3 are arranged at intervals along the extension direction of the guide channel 2, and the guide channel 2 passes through the two magnetic cores 3 in sequence.

[0041] It should be noted that, in this embodiment, a partition 5 is disposed between the two magnetic cores 3, and both end surfaces of the partition 5 are closely matched with the two magnetic cores 3 to play the following roles:

[0042] 1. Isolate the magnetic field: The partition 5 can prevent the magnetic field from propagating inside the sensor, thereby ensuring that the magnetic field can only be conducted through the magnetic core 3, reducing the leakage and interference of the magnetic field, and improving the accuracy and stability of the sensor.

[0043] 2. Mechanical support: The partition 5 can serve as a supporting structure for fixing the magnetic cores 3, maintaining the spacing and position between the magnetic cores 3 stable, and preventing the magnetic cores 3 from shifting or deforming, thereby affecting the working performance of the sensor.

[0044] 3. Electrical isolation: The partition 5 can prevent the electrical connection between the magnetic cores 3, avoid short circuit or electrical interference, and ensure the safety and stability of the sensor.

[0045] 4. Protect the magnetic core: The partition 5 can protect the magnetic core 3, prevent the impact and damage of the external environment, and extend the service life of the magnetic core.

[0046] In this embodiment, two magnetic cores 23 are provided, which has the following advantages compared to a single magnetic core structure:

[0047] 1. Improve sensitivity: By setting two magnetic cores 3, the sensor's ability to capture the magnetic field around the conductor to be measured can be improved, and the sensor's sensitivity and measurement range can be improved. This can better capture the change of the current signal and improve the sensor's measurement accuracy.

[0048] 2. Improved linearity: Using two magnetic cores 3 can reduce the nonlinear effect of the magnetic field and improve the linearity and stability of the sensor. This helps to reduce measurement errors and ensure a linear relationship between the sensor output and input current.

[0049] 3. Improve anti-interference ability: By setting two magnetic cores 3, the magnetic field capture area of ​​the sensor can be increased and the anti-interference ability of the sensor can be improved. This helps to reduce the influence of external magnetic fields and improve the stability and reliability of the sensor.

[0050] 4. Improved resolution: The two magnetic cores 3 can provide a larger magnetic field receiving area, increase the sensitivity of the sensor to the current signal, and improve the resolution of the sensor. This helps to measure the change of the current signal more finely and improve the measurement accuracy of the sensor.

[0051] The two end surfaces of the partition 5 are closely matched with the magnetic core 3, which can achieve the following advantages:

[0052] 1. Magnetic circuit integrity: The partition 5 can fix the two magnetic cores 3 together to form a complete magnetic circuit structure, avoiding magnetic field leakage. This can ensure the continuity and integrity of the magnetic field conduction and improve the conduction efficiency of the magnetic core 3.

[0053] 2. Reduction of magnetic resistance: Through the close cooperation between the partition 5 and the magnetic core 3, the additional magnetic resistance in the magnetic circuit can be reduced, the resistance in the magnetic field conduction process can be reduced, the energy loss and dissipation can be reduced, and the efficiency and performance of the magnetic core 3 can be improved.

[0054] 3. Magnetic field stability: The close fit between the partition 5 and the magnetic core 3 can increase the stability of the magnetic circuit, prevent the magnetic core 3 from shifting or deforming during rotation, maintain the stability and consistency of the magnetic field, and improve the working stability of the current sensor.

[0055] 4. Improve high temperature resistance: The partition 5 can fix the magnetic core 3 and improve the high temperature resistance of the magnetic element. In a high temperature environment, the magnetic core 3 is prone to thermal expansion or deformation, and the fixed setting of the partition 5 can effectively prevent this from happening.

[0056] 5. Easy to install and maintain: The close fit between the partition 5 and the magnetic core 3 can make the assembly and maintenance of the magnetic core 3 more convenient and simple, reduce the complexity and difficulty of operation, and improve production efficiency and equipment maintainability.

[0057] In summary, in this embodiment, the main reason for the close fit between the partition 5 and the magnetic core 3 is to fix the position of the magnetic core 3, reduce magnetic leakage, improve the integrity of the magnetic circuit, and facilitate installation and maintenance. This can effectively optimize the performance and efficiency of the magnetic conductive part and improve the working stability and reliability of the current sensor.

[0058] Embodiment 3

[0059] See also Figures 1 to 6 As shown, on the basis of the second embodiment, further, the skeleton 1 includes a first skeleton 11 and a second skeleton 12, and the first skeleton 11 and the second skeleton 12 are arranged at intervals to form a guide channel 2; the magnetic core 3 includes a first magnetic core 31 and a second magnetic core 31 arranged at intervals, the first magnetic core 31 is movably arranged in the first skeleton 11, and the second magnetic core 32 is movably arranged in the second skeleton 12; the magnetic core 3 includes two first magnetic cores 31, and the two first magnetic cores 31 can be rotatably arranged in the first skeleton 11 so that the cross-sections of the two first magnetic cores 31 are not in the same plane; the magnetic core 3 includes two second magnetic cores 32, and the two second magnetic cores 32 can be rotatably arranged in the second skeleton 12 so that the cross-sections of the two second magnetic cores 32 are not in the same plane.

[0060] Specifically, in this embodiment, the plane along the extension direction of the flow guide channel 2 is the cutting plane, and the skeleton 1 is cut into the first skeleton 11 and the second skeleton 12 with the cutting plane as the center plane. The skeleton 1 is set to an openable and closable structure. During measurement, the skeleton 1 is opened and sleeved on the wire to be measured and then closed. The magnetic core 3 is cut into the first magnetic core 31 and the second magnetic core 32 along the plane along the extension direction of the flow guide channel 2 as the cutting plane. The first magnetic core 31 is rotatably set in the first skeleton 11, and the second magnetic core 32 is rotatably set in the second skeleton 12. In order to rotate the magnetic core 3, a plastic buckle can be set on the outer side of one of the first magnetic cores 31 near the cross section, and then when in use, the plastic buckle can be moved so that the cross sections of the two first magnetic cores 31 are not on the same horizontal plane; a plastic buckle can also be set on the outer side of one of the second magnetic cores 32 near the cross section, and then when in use, the plastic buckle can be moved so that the cross sections of the two second magnetic cores 32 are not on the same horizontal plane; the purpose of this setting is to solve the problem of a large amount of leakage magnetic flux caused by the failure to accurately align the cutting plane of the magnetic core 3. By designing that the cross sections of the two magnetic cores 3 are not on the same horizontal plane, the possibility of leakage magnetic flux can be reduced.

[0061] The traditional current sensor will have a lot of magnetic leakage problems due to the failure to accurately align the cutting plane of the magnetic core 3, which is specifically manifested as follows:

[0062] 1. Incomplete magnetic circuit: Failure to accurately align the cutting plane of the magnetic core 3 will result in an incomplete magnetic circuit. The magnetic field cannot form a closed loop, making it impossible for the magnetic field to be fully conducted and transmitted, thereby causing magnetic leakage.

[0063] 2. Increased magnetic resistance: When the cutting plane of the magnetic core 3 is not precisely aligned, additional magnetic resistance will be generated, causing the magnetic field to encounter increased resistance during the conduction process, resulting in increased magnetic field leakage.

[0064] 3. Magnetic flux loss: Due to the incomplete magnetic circuit and increased magnetic resistance, the magnetic flux cannot completely pass through the magnetic core, and part of the magnetic flux will cause leakage, reducing the conduction efficiency of the magnetic field.

[0065] 4. Influence on magnetic induction intensity: Leakage flux will reduce the magnetic induction intensity of the magnetic field, affecting the performance and efficiency of the magnetic core 3. In the magnetic core 3, leakage flux will affect its magnetic properties and reduce its use effect.

[0066] Based on the problem of magnetic leakage, the utility model adopts a plastic buckle arranged near the cross section of the outer side of one of the first magnetic cores 31, and then when in use, by moving the plastic buckle, the cross sections of the two first magnetic cores 31 are not on the same horizontal plane; a plastic buckle can also be arranged near the cross section of the outer side of one of the second magnetic cores 32, and then when in use, by moving the plastic buckle, the cross sections of the two second magnetic cores 32 are not on the same horizontal plane; thereby avoiding the problem of needing to cut the cross section for alignment and reducing the possibility of magnetic leakage. In this embodiment, a plastic buckle is used to rotate the magnetic core 3 so that the cross section of the magnetic core 3 is not on the same horizontal plane, but due to the influence of the turns of the coil, the sliding distance of the plastic buckle is not large, as long as the cross section of the rotating magnetic core 3 is not on the same horizontal line as the cross section of the other magnetic core 3. In this embodiment, the use of a plastic buckle can achieve the purpose of rotating the magnetic core 3 and save costs. Such a design can effectively improve the continuity and integrity of the magnetic circuit, improve the conduction efficiency of the magnetic field, and reduce magnetic leakage. Reducing magnetic leakage has the following advantages:

[0067] 1. Improve efficiency: Reducing magnetic leakage can improve the conduction efficiency and performance of the magnetic core 3. Magnetic leakage will cause energy loss and dissipation of the magnetic field, reducing the efficiency of the magnetic core 3, while reducing magnetic leakage can effectively improve the conduction efficiency of the magnetic field and improve the working efficiency of the current sensor.

[0068] 2. Improve stability: Reducing magnetic leakage can improve the stability and reliability of the magnetic core 3. Magnetic leakage can cause instability and fluctuation of the magnetic field, affecting the normal use of the current sensor, while reducing magnetic leakage can maintain the stability of the magnetic field and improve the working stability of the current sensor.

[0069] 3. Improve performance: Reducing magnetic leakage can improve the performance and response speed of the magnetic core 3. Magnetic leakage will lead to magnetic field loss and energy consumption, reducing the performance of the magnetic core 3, while reducing magnetic leakage can improve the response speed and performance level of the magnetic field.

[0070] 4. Reduce energy consumption: Reducing magnetic flux leakage can reduce energy consumption and loss of the magnetic core 3. Magnetic flux leakage will lead to energy loss and waste, increase energy consumption and cost of equipment, while reducing magnetic flux leakage can reduce energy consumption and improve energy utilization efficiency.

[0071] 5. Increase service life: Reducing magnetic leakage can extend the service life of the magnetic core 3. Magnetic leakage will cause loss of magnetic field and aging of magnetic conductive parts, shortening the service life of the magnetic core 3, while reducing magnetic leakage can slow down the aging speed of the magnetic core 3 and extend the service life of the magnetic core 3.

[0072] In particular, in the magnetic core 3, a partition 5 is provided between two magnetic cores 3, and when the plastic buckle is slid to make the magnetic core 3 movable, it is possible to prevent the two first magnetic cores 31 or the two second magnetic cores 32 from rotating together due to mutual friction. By rotating one of the first magnetic cores 31 or one of the second magnetic cores 32, the cut cross sections thereof are not on the same horizontal plane, which reduces the possibility of magnetic leakage and improves the output power of the sensor.

[0073] It should be noted that setting the skeleton 1 as an openable structure, that is, designing the current sensor as an openable structure can realize the rapid installation and removal of the current sensor without damaging the wire to be measured. For example, when measuring the small fault current of a wind farm, since the wires to be measured in the wind farm are fixed, the current sensor is designed as an openable structure. When in use, the current sensor is opened and hung on the wire to be measured and then closed. After use, the current sensor is opened and removed, or when maintenance is required, the current sensor can be directly opened for inspection and maintenance, so that the sensor can be quickly installed and removed without damaging the wire to be measured. The current sensor with an openable structure has greater flexibility, can adapt to circuits of different sizes and shapes, and can adjust the position and angle of the sensor as needed to ensure the close connection between the sensor and the circuit; due to the openable structure, it becomes easier to maintain and replace the current sensor. The staff can easily open the sensor for maintenance and overhaul, reducing the difficulty and time cost of operation during maintenance. The current sensor with an openable structure can better protect the internal components and reduce the impact of external factors on the sensor. At the same time, the installation and disassembly process is simpler and safer, reducing the operational risk.

[0074] Furthermore, the use of a high permeability magnetic core 3 in this embodiment can effectively concentrate the magnetic field lines and improve the conduction efficiency and performance of the magnetic field. This type of magnetic core material usually has a high permeability and low hysteresis characteristics, which can reduce the energy loss of the magnetic field and improve the efficiency and performance of the device. The lower hysteresis characteristics, that is, the magnetization curve of the magnetic material is smooth when the magnetic field changes, and no obvious hysteresis loop will be produced. This characteristic enables the magnetic core to respond to changes in the external magnetic field more quickly, improving the sensitivity and response speed of the device. The high permeability annular magnetic core has good magnetic conductivity, can effectively guide and conduct the magnetic field, and improve the magnetic coupling efficiency and transmission effect of the current sensor.

[0075] Applying the magnetic core 3 with high magnetic permeability to the current sensor can, first, improve the sensitivity of the sensor: the magnetic core 3 with high magnetic permeability can better concentrate the magnetic field, making the sensor more sensitive to the current. This means that the sensor can measure the current value more accurately and improve the precision and accuracy of the measurement. Second, reduce the hysteresis loss: the magnetic core 3 with high magnetic permeability usually has a lower hysteresis characteristic, that is, the magnetization curve is smooth when the magnetic field changes, and no obvious hysteresis loop is generated. This can reduce the energy loss of the magnetic core 3 and improve the efficiency and stability of the sensor. Third, improve the linearity of the sensor: the magnetic core 3 with high magnetic permeability can improve the linearity of the sensor, making the relationship between the output signal of the sensor and the input current more stable and linear. This helps to reduce errors and improve the accuracy of measurements. Fourth, improve the anti-interference ability of the sensor: the magnetic core 3 with high magnetic permeability can effectively suppress the interference of the external magnetic field and improve the anti-interference ability of the sensor.

[0076] In summary, the use of a magnetic core 3 with high magnetic permeability can improve the performance and stability of the current sensor, so that the sensor has higher sensitivity, precision and accuracy when measuring current, and can better measure currents with small amplitudes.

[0077] Embodiment 4

[0078] See also Figures 1 to 6 As shown, on the basis of the third embodiment, the coil 4 is further wound with enameled wire.

[0079] It should be noted that the coil 4 in this embodiment is wound with enameled wire, which is a material commonly used for winding the coil 4 and is mainly composed of a metal conductor (such as copper, aluminum, etc.) and an insulating enameled layer. The enameled wire is selected because it has the following advantages and is suitable for winding the coil:

[0080] 1. Excellent anti-interference performance: Enameled wire is an insulated wire that can reduce the impact of external interference on the current signal, thereby increasing the magnetic induction intensity and improving the sensitivity and stability of the current sensor.

[0081] 2. Good insulation performance: The insulating enameled layer of the enameled wire can effectively isolate the electrical contact between the conductors and between the conductors and the external environment, prevent short circuit and leakage, and ensure the safety and reliability of the coil.

[0082] 3. Good heat resistance and wear resistance: The insulating enameled layer of the enameled wire usually has good heat resistance and wear resistance, can maintain stability in high temperature environments, is not easily affected by the external environment, and extends the service life of the coil.

[0083] 4. Easy to wind and install: The enameled wire is soft and plastic, easy to wind into coils of various shapes, and easy to connect and install, reducing the complexity of manufacturing and installation.

[0084] 5. Low cost: The manufacturing cost of enameled wire is relatively low, and it is an economical and practical coil winding material, suitable for mass production and application.

[0085] Specifically, the coil 4 wound with enameled wire plays the following roles in the current sensor:

[0086] 1. Electromagnetic induction: When the conductor to be measured passes through the coil 4, the current in the conductor will generate a magnetic field, and the magnetic flux inside the coil 4 wound with enameled wire will change accordingly. According to Faraday's law of electromagnetic induction, the change in the magnetic flux in the coil 4 will induce an induced electromotive force, thereby generating an induced current. By measuring the induced current in the coil 4, the current in the conductor can be indirectly measured.

[0087] 2. Conversion signal: The induced current generated by the coil 4 wound with enameled wire will be converted into a corresponding voltage or current output signal, which will be output to the measuring instrument or control system after passing through the signal processing circuit. In this way, the measurement and monitoring of the current-carrying conductor can be realized.

[0088] 3. Isolation protection: The coil 4 wound with enameled wire plays an isolation and protection role in the current sensor. It can isolate the conductor to be measured from the measuring instrument or control system, avoid electrical isolation problems caused by current measurement, and ensure the accuracy and safety of measurement.

[0089] In summary, the enameled wire has excellent electrical conductivity, insulation performance, heat resistance, wear resistance and cost-effectiveness, and is suitable for winding the coil 4. In the current sensor, the coil 4 is usually used to measure the current-carrying conductor. The function of the coil 4 is to sense the current passing through the conductor through the Faraday electromagnetic induction principle and convert the current signal into a corresponding voltage or current output signal, thereby realizing the measurement of the current.

[0090] Embodiment 5

[0091] See also Figures 1 to 6 As shown, on the basis of the fourth embodiment, further, the skeleton 1 includes two hollow structures, the hollow structure includes a first baffle 6 and a second baffle 7, the first baffle 6 and the second baffle 7 are arranged at intervals along the extension direction of the guide channel 2, and the first baffle 6 and the second baffle 7 are connected by a connecting plate 8; the two hollow structures are also connected by the connecting plate 8 to form the skeleton 1. The partition 5, the first baffle 6, the second baffle 7, and the connecting plate 8 are all plates made of PCB material. It should be noted that the partition 5, the first baffle 6, the second baffle 7, and the connecting plate 8 are all plates made of PCB material, which can greatly reduce the construction cost and also have the following advantages:

[0092] 1. Mechanical support: The PCB board has good mechanical strength and stability and can be used in the design of the skeleton 1 to support the structure of the sensor, maintain the shape and stability of the sensor, and improve the durability and reliability of the sensor.

[0093] 2. Electrical isolation: PCB board materials have good electrical insulation properties, which can isolate different circuits or components in the sensor, prevent interference or short circuit between circuits, and improve the electrical performance and stability of the sensor.

[0094] 3. Thermal management: PCB board materials have good thermal conductivity and can be used as a skeleton 1 to manage the heat distribution in the sensor, help the sensor dissipate heat, keep the sensor's operating temperature stable, and improve the sensor's performance and reliability.

[0095] 4. Integrated circuit: PCB board can easily integrate integrated circuits and components, making the sensor design more compact and efficient. By integrating integrated circuits and sensor components on the skeleton 1, the structure and manufacturing process of the sensor can be simplified, reducing costs and improving production efficiency.

[0096] 5. Customized design: The PCB board can be customized according to the specific requirements of the sensor, including shape, size, layout, etc. Through the customized designed skeleton 1, that is, the PCB board can be adapted and connected according to the shape of the first baffle 6 and the second baffle 7 to form the required skeleton 1, it can better adapt to the specific application requirements of the sensor and improve the performance and function of the sensor.

[0097] The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A current sensor for an online monitoring device of a wind farm, characterized in that: include: A frame, wherein the frame is formed with a flow-conducting channel for passing a transmission wire of a current to be measured; A magnetic core, wherein the magnetic core is disposed in the frame, and the flow guide channel passes through the magnetic core, so that the current to be measured generates an induced magnetic field under the action of electromagnetic induction; A coil, wound around the guide channel, for generating an induced current under the action of an induced magnetic field; as well as A detection circuit is connected to the coil and is used to detect the generated induced current.

2. The current sensor of the wind farm online monitoring device according to claim 1, characterized in that: The current sensor comprises two magnetic cores, which are arranged at intervals along the extension direction of the flow guiding channel, and the flow guiding channel passes through the two magnetic cores in sequence.

3. The current sensor of the wind farm online monitoring device according to claim 1, characterized in that: The frame includes a first frame and a second frame, and the first frame and the second frame are spaced apart to form the guide channel.

4. The current sensor of the wind farm online monitoring device according to claim 3, characterized in that: The magnetic core comprises a first magnetic core and a second magnetic core which are arranged at intervals. The first magnetic core is movably arranged in a first frame, and the second magnetic core is movably arranged in a second frame.

5. The current sensor of the wind farm online monitoring device according to claim 4, characterized in that: The magnetic core includes two first magnetic cores, and the two first magnetic cores are rotatably arranged in the first skeleton so that the cross sections of the two first magnetic cores are not in the same plane.

6. The current sensor of the wind farm online monitoring device according to claim 4, characterized in that: The magnetic core includes two second magnetic cores, and the two second magnetic cores are rotatably arranged in the second skeleton so that the cross sections of the two second magnetic cores are not in the same plane.

7. The current sensor of the wind farm online monitoring device according to any one of claims 1 to 6, characterized in that: The coil is wound with enameled wire.

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