CN207798899U - A kind of current sensor and monitoring system - Google Patents
A kind of current sensor and monitoring system Download PDFInfo
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Abstract
This application discloses a kind of current sensors, including insulation board, the first Rogowski coil and the second Rogowski coil.First Rogowski coil is fixed on the one side of insulation board, and the second Rogowski coil is fixed on the another side of insulation board.The number of turns of first Rogowski coil is less than the number of turns of the second Rogowski coil.Current sensor can to circuit under power frequency the low current range and signal of high current range measures in high frequency.The case where to avoid since there are iron cores when being measured using traditional ferromagnetic formula current transformer, containing DC component in primary current is easily saturated, and tested current range becomes smaller, and frequency band is narrow, and pickoff signals are easy distortion.During measurement amplitude prodigious fault current, is not in magnetic saturation phenomenon, there is excellent linear characteristic, be suitably applied to the higher occasion of current measurement required precision.Present invention also provides the monitoring systems comprising above-mentioned current sensor, to complete monitoring process.
Description
Technical Field
The application relates to the technical field of electromagnetic measurement, in particular to a current sensor and a monitoring system.
Background
Current sensors are finding increasingly widespread use in power systems. In various practical scenes of a direct current transmission system, a variable frequency speed regulation device, an inverter device, a UPS (uninterrupted power supply), an inverter welding machine, a transformer substation, electrolytic plating, a numerical control machine tool, a microcomputer monitoring system, a power grid monitoring system and the like needing isolation detection of current, a current sensor is used for detecting non-sinusoidal current, so that whether a power circuit and equipment are in a normal operation state or not is judged. The current sensor converts the detected information into an electric signal meeting certain standard requirements or a signal in other required forms according to a certain rule and outputs the signal, so that the requirements of information transmission, processing, storage, display, recording, control and the like are met.
Current sensors can be broadly classified into two categories according to their operating principles: one type is a measuring device, such as a shunt, for determining the magnitude of a measured current based on the voltage drop across a known resistance; the other type is a measuring device for determining the magnitude of the measured current according to the magnetic field established by the measured current, namely a magnetic sensor, such as a ferromagnetic current transformer. The biggest problem in using a shunt for detection is that there is no isolation between the input and the output, and when a shunt is used to measure high frequency or large current, it inevitably has an inductive character. Therefore, when the shunt is connected to the power line, the waveform of the measured current is affected, and the current signal cannot be transmitted really.
The ferromagnetic current transformer has high insulating strength, stable performance and low power consumption, can bear large load, and can be installed without disconnecting the circuit to be tested. However, the ferromagnetic current transformer uses an iron core material, and is not ideal in magnetization characteristics, and is easily saturated when a primary current contains a direct current component, so that the range of the measured current becomes small, the frequency band is narrow, the picked-up signal is easily distorted, and the ferromagnetic current transformer is not suitable for being applied to occasions with high requirements on current measurement accuracy. For example, when transient current with increased amplitude or high di/dt current is detected, the ferromagnetic current transformer cannot reflect the detected current without distortion, and the measurement error is large.
SUMMERY OF THE UTILITY MODEL
The application provides a current sensor and a monitoring system to solve the problems that the current sensor has small detection current range, narrow frequency band and distortion of picked-up signals, and the measurement error is large.
A current sensor comprising an insulating plate, a first Rogowski coil and a second Rogowski coil;
a through hole is formed in the center of the insulating plate;
a lead is arranged on the axis of the through hole;
the first Rogowski coil is fixed on one surface of the insulating plate;
the second Rogowski coil is fixed on the other surface of the insulating plate;
the number of turns of the first Rogowski coil is less than that of the second Rogowski coil;
frameworks with the same structure and size are arranged on the axes of the first Rogowski coil and the second Rogowski coil;
one end of each of the first Rogowski coil and the second Rogowski coil is provided with a first coil end;
the other ends of the first Rogowski coil and the second Rogowski coil are respectively provided with a second coil end;
a first signal lead is arranged on the end head of the first coil;
the first signal lead is connected with the end head of the first coil;
a second signal lead is arranged on the end head of the second coil;
the second signal lead is connected with the end head of the second coil.
Further, the skeleton consists of 4 round rods;
the 4 round rods are connected in a surrounding mode through the first Rogowski coil and the second Rogowski coil in an end-to-end mode to form a square structure.
Further, the insulating plate comprises a first half ring, a second half ring, a first coupling head and a second coupling head;
one end of the first half ring is connected with one end of the second half ring through the first coupling head;
the other end of the first half ring is connected with the other end of the second half ring through the second joint.
Further, the first coupling head and the second coupling head are plug-in coupling heads;
the two ends of the first coupling head and the second coupling head are in the shape of elastic bayonets.
Further, the first Rogowski coil and the second Rogowski coil are uniformly wound into a spiral shape by adopting enameled wires;
the shielding layers are uniformly wound outside the first Rogowski coil and the second Rogowski coil by conductive metal thin strips;
and an insulating protective layer is arranged outside the shielding layer.
Further, the insulating plate is an epoxy resin plate.
A monitoring system comprising the current sensor, an in-situ module, a remote module, and an optical fiber;
the current sensor is electrically connected with the in-situ module;
the on-site module is connected with the remote module through the optical fiber;
the local module comprises a data acquisition unit and an electro-optical signal conversion unit;
the current sensor is electrically connected with the electro-optical signal conversion unit through the data acquisition unit;
the data acquisition unit is connected with the optical fiber through the electro-optical signal conversion unit;
the remote module comprises a photoelectric signal conversion unit and a data processing and analyzing unit;
the optical fiber is electrically connected with the data processing and analyzing unit through the photoelectric signal conversion unit.
Further, the monitoring system further comprises a non-metallic housing;
the current sensor, the in-situ module, the remote module and the optical fiber are encapsulated inside the non-metallic housing.
The beneficial effect of this application is:
in view of the above, the present application provides a current sensor including an insulating plate, a first Rogowski coil, and a second Rogowski coil. The first Rogowski coil is fixed on one surface of the insulating plate, and the second Rogowski coil is fixed on the other surface of the insulating plate. The number of turns of the first Rogowski coil is smaller than the number of turns of the second Rogowski coil. The current sensor can measure signals of a circuit in a small current range under power frequency and a large current range under high frequency. Therefore, the current sensor avoids the problem that the current sensor is easy to saturate under the condition that primary current contains direct-current components due to the existence of the iron core when the traditional ferromagnetic current transformer is used for measurement, the range of the measured current is reduced, the frequency band is narrow, and the picked-up signal is easy to distort. In the process of measuring the fault current with large amplitude, the magnetic saturation phenomenon can not occur, the linear characteristic is excellent, and the method is suitable for being applied to occasions with higher requirements on the current measurement precision. The application also provides a monitoring system comprising the current sensor to complete the monitoring process.
Drawings
In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without any creative effort.
Fig. 1 is a schematic structural diagram of a current sensor according to an embodiment of the present disclosure;
FIG. 2 is a schematic end view of a current sensor according to an embodiment of the present disclosure;
FIG. 3 is a schematic view of the partial cross-section of FIG. 2;
FIG. 4 is a model of an embodiment of the present application for analyzing and modeling the output of a current sensor;
FIG. 5 is an enlarged view of a current sensor output analysis build model according to an embodiment of the present application;
FIG. 6 is a simulation analysis diagram of the number of coil segments in a current sensor according to an embodiment of the present application;
fig. 7 is a schematic structural diagram of a monitoring system according to an embodiment of the present application.
The sensor comprises a current sensor 1, an insulating plate 2, a first Rogowski coil 3, a second Rogowski coil 4, a through hole 5, a lead 6, a framework 7, a first coil end 8, a second coil end 9, a first signal lead 10, a second signal lead 11, a round rod 12, a first half ring 13, a second half ring 14, a first coupling head 15, a second coupling head 16, a shielding layer 17, an insulating protective layer 18, an in-situ module 19, a remote module 20, an optical fiber 21, a data acquisition unit 22, an electro-optical signal conversion unit 23, an electro-optical signal conversion unit 24, a data processing and analyzing unit 25 and a nonmetal shell 26.
Detailed Description
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following examples do not represent all embodiments consistent with the present application.
Current sensors can be broadly classified into two categories according to their operating principles: one type is a measuring device, such as a shunt, for determining the magnitude of a measured current based on the voltage drop across a known resistance; the other type is a measuring device for determining the magnitude of the measured current according to the magnetic field established by the measured current, namely a magnetic sensor, such as a ferromagnetic current transformer. The biggest problem in using a shunt for detection is that there is no isolation between the input and the output, and when a shunt is used to measure high frequency or large current, it inevitably has an inductive character. Therefore, when the shunt is connected to the power line, the waveform of the measured current is affected, and the current signal cannot be transmitted really. The ferromagnetic current transformer has high insulating strength, stable performance and low power consumption, can bear large load, and can be installed without disconnecting the circuit to be tested. However, the ferromagnetic current transformer uses an iron core material, and is not ideal in magnetization characteristics, and is easily saturated when a primary current contains a direct current component, so that the range of the measured current becomes small, the frequency band is narrow, the picked-up signal is easily distorted, and the ferromagnetic current transformer is not suitable for being applied to occasions with high requirements on current measurement accuracy. For example, when transient current with increased amplitude or high di/dt current is detected, the ferromagnetic current transformer cannot reflect the detected current without distortion, and the measurement error is large.
The present application provides a current sensor, said current sensor 1 comprising an insulating plate 2, a first Rogowski coil 3 and a second Rogowski coil 4;
the center of the insulating plate 2 is provided with a through hole 5;
a lead 6 is arranged on the axis of the through hole 5;
the first Rogowski coil 3 is fixed on one surface of the insulating plate 2;
the second Rogowski coil 4 is fixed on the other surface of the insulating plate 2;
the number of turns of said first Rogowski coil 3 is smaller than the number of turns of said second Rogowski coil 4;
frameworks 7 with the same structure and size are arranged on the axes of the first Rogowski coil 3 and the second Rogowski coil 4;
one end of each of the first Rogowski coil 3 and the second Rogowski coil 4 is provided with a first coil end 8;
the other ends of the first Rogowski coil 3 and the second Rogowski coil 4 are both provided with second coil end heads 9;
a first signal lead 10 is arranged on the first coil end 8;
the first signal lead 10 is connected with the first coil end 8;
a second signal lead 11 is arranged on the end head 9 of the second coil;
the second signal lead 11 is connected to the second coil end 9.
Specifically, refer to fig. 1 for a schematic structural diagram of a current sensor according to an embodiment of the present application, and fig. 2 is a schematic structural diagram of an end face of a current sensor according to an embodiment of the present application;
the first Rogowski coil 3 is uniformly wound around the former 7 of the first Rogowski coil 3 axis with an enameled wire. The second Rogowski coil 4 is uniformly wound around the bobbin 7 of the second Rogowski coil 4 axis with an enamel wire. The framework 7 can be made of non-magnetic materials such as plastics, ceramics and the like, and the relative magnetic permeability of the framework is the same as that of air. Since the magnetic circuit of the first Rogowski coil 3 and the second Rogowski coil 4 does not contain a core, there is no saturation problem. A first Rogowski coil 3 is fixed to one side of the insulating plate 2 and a second Rogowski coil 4 is fixed to the other side of the insulating plate 2.
Fig. 4 is a view showing an output analysis building model of the current sensor 1 according to the embodiment of the present application, and fig. 5 is an enlarged view showing the output analysis building model of the current sensor 1 according to the embodiment of the present application. The specific process of analyzing the output signal of the current sensor 1 is as follows.
Since the first Rogowski coil 3 and the second Rogowski coil 4 have the same structure and only have different numbers of turns, only one model needs to be established.
In fig. 5, the magnetic induction density in the coil with the kth turn number is:
the outside magnetic induction intensity is:
wherein, BknThe magnetic induction intensity in the coil with the kth turn number, BkmIs the magnetic induction outside the k-th turn coil, murμ0Is an environmentPermeability, i (t) is the AC current at the O point of the coil center, HknThe magnetic field intensity of the inner edge of the k-th turn coil, HkmThe magnetic field intensity outside the coil with the kth turn number, l is the distance from the center O point of the coil to the inner edge of the coil, d is the diameter of the coil, dkIs the perpendicular distance from the cross section of the k-th turn coil to the cross section of the coil center point O.
If l>8d, then Bkn/Bkm<1.008, the coil cross-section magnetic field is considered to be equal everywhere.
The magnetic induction intensity perpendicular to the section direction of the k turn number coil is as follows:
wherein, Bk' is magnetic induction perpendicular to the section direction of the k-th turn coil, /)kIs the distance of the coil center O from the center of the coil cross-section.
The magnetic flux perpendicular to the section direction of the k-th turn coil is:
wherein phi iskIs the magnetic flux perpendicular to the section direction of the coil with the k turns, and S is the section area with the k turns.
Wherein,
and (3) magnetic linkage:
and (3) voltage output:
where N' represents the number of coil turns.
For example, if the rated current, i.e. the coil center conductor current is 100A, d is 5mm, l is 21mm, the number of turns N 'of the first Rogowski coil 3 is 400 turns, the number of turns N' of the second Rogowski coil 4 is 2000 turns, and the outputs u of the two coils are calculatedout5.04mv and 25.24mv respectively.
Since the number of turns of the first Rogowski coil 3 is smaller than the number of turns of the second Rogowski coil 4, the first Rogowski coil 3 is used for enabling the measurement of large currents and the second Rogowski coil 4 is used for enabling the measurement of small currents. When the line is under power frequency, detecting current by adopting a first Rogowski coil 3; when the line is in a fault condition at high frequencies, the current is detected using the second Rogowski coil 4. The detected data is transmitted through the first signal lead 10 and the second signal lead 11. Therefore, signals of the circuit in a small current range under power frequency and a large current range under high frequency are detected. The milliampere level can be measured in a small current range, and the hundred ampere level current can be measured in a large current range. Therefore, the current sensor 1 avoids the problems that the conventional ferromagnetic current transformer is easy to saturate under the condition that primary current contains direct-current components due to the existence of an iron core when the measurement is carried out, the range of the measured current is reduced, the frequency band is narrow, and the picked-up signal is easy to distort. By designing the first Rogowski coil 3 and the second Rogowski coil 4 which have the same structure and different numbers of turns, signals of a line in a small current range under power frequency and a large current range under high frequency can be measured. In the process of measuring the fault current with large amplitude, the magnetic saturation phenomenon can not occur, the linear characteristic is excellent, and the method is suitable for being applied to occasions with higher requirements on the current measurement precision.
As can be seen from the above technical solutions, the present application provides a current sensor, where the current sensor 1 includes an insulating plate 2, a first Rogowski coil 3, and a second Rogowski coil 4. The first Rogowski coil 3 is fixed to one side of the insulating plate 2 and the second Rogowski coil 4 is fixed to the other side of the insulating plate 2. The number of turns of said first Rogowski coil 3 is smaller than the number of turns of said second Rogowski coil 4. The current sensor can measure signals of a circuit in a small current range under power frequency and a large current range under high frequency. Therefore, the current sensor 1 avoids the problems that the conventional ferromagnetic current transformer is easy to saturate under the condition that primary current contains direct-current components due to the existence of an iron core when the measurement is carried out, the range of the measured current is reduced, the frequency band is narrow, and the picked-up signal is easy to distort. In the process of measuring the fault current with large amplitude, the magnetic saturation phenomenon can not occur, the linear characteristic is excellent, and the method is suitable for being applied to occasions with higher requirements on the current measurement precision. The application also provides a monitoring system comprising the current sensor to complete the monitoring process.
Further, the skeleton 7 is composed of 4 round rods 12;
the 4 round rods 12 are connected in a winding mode end to end through the first Rogowski coil 3 and the second Rogowski coil 4 to form a square structure.
Specifically, referring to fig. 6, a diagram of simulation analysis of the number of coils in a current sensor according to an embodiment of the present application is shown. Where N represents the number of segments into which the coil is divided and d represents the coil diameter. And (3) simulating by using MATLAB software under the condition that the number of the coils in the current sensor is 1, 2, 3, 4 and 8 respectively to obtain a relational graph between the percentage error and the distance, namely the diameter d of the coil. Thereby obtaining the influence of the number of the segments N on the accuracy of the circuit measurement result. As can be seen from fig. 6, the percentage error of the circuit measurement results is different for different numbers of segments N. When the current sensor 1 formed by uniformly placing 4 sections of coils around the tested lead 6 is adopted, namely the included angle of adjacent sections of coils in the current sensor is 90 degrees, the percentage errors measured by the current sensor 1 in the range of the coil diameter d shown in fig. 6 are all less than 0.2 percent, and the requirement of measurement precision is met. When the number of segments N is less than 4, the included angle between adjacent coils is less than 90 degrees, and the percentage error of the measurement result is obviously larger than that of the measurement result when the number of segments N is equal to 4. When the number of segments N is greater than 4, it can be clearly seen that the percentage errors of the measurement results are less than 0.1% in the range of the coil diameter d shown in fig. 6. Combining the results obtained in fig. 6, when the coil diameter d is small, the larger the number N of segments is, the smaller the percentage error of the measurement result is, and when the coil diameter d is large, the percentage errors of the measurement results under different numbers N of coil segments are close. Therefore, considering the measurement accuracy and the cost comprehensively, 4 segments of coils are selected to form the Rogowski coil so as to manufacture the current sensor.
4 round rods 12 are connected end to end through the first Rogowski coil 3 and the second Rogowski coil 4 in a surrounding mode to form a square structure, so that the processing and winding are easy, more coil turns can be wound in a small space, and the winding device is easy to install in the small space.
Further, the insulating plate 2 comprises a first half-ring 13, a second half-ring 14, a first coupling head 15 and a second coupling head 16;
one end of the first half ring 13 is connected with one end of the second half ring 14 through the first coupling head 15;
the other end of the first half ring 13 is connected to the other end of the second half ring 14 via the second coupling 16.
Specifically, the first Rogowski coil 3 and the second Rogowski coil 4 are each formed by 4 segments of coils, the 4 segments of coils are divided into two groups, each group of 2 segments of adjacent coils form an L-shape by forming the 2 segments of adjacent coils, wherein any group of coils is located in the first half ring 13, and the other group of coils is located in the second half ring 14. When the circuit needs to be detected, one end of the first half ring 13 is moved out of one end of the first coupling head 15, and the insulating plate 2 is opened to form an open-close type structure. The first half ring 13 is passed around the line so that the lead 6 to be tested is caught between the first half ring 13 and the second half ring 14, and then the first half ring 13 is inserted into one end of the first coupling head 15 so that the entire current sensor 1 is in a closed loop shape. Outputting a signal, i.e. an output voltage U, via a first signal lead 10 and a second signal lead 11outTherefore, on-line monitoring of the current loop in operation can be realized. Furthermore, the current in the tested lead 6 can be conveniently detected without breaking the lead 6On, the current loop in operation can be measured. Second coupling 16 facilitates the rotational coupling and mounting of the other end of first half 13 to the other end of second half 14.
Further, the first coupling head 15 and the second coupling head 16 are plug-in coupling heads;
the two ends of the first coupling head 15 and the second coupling head 16 are in the shape of elastic bayonets.
Specifically, the first coupling head 15 and the second coupling head 16 are plug-in coupling heads, so that the first half ring 13 and the second half ring 14 are connected by using plug-in butt joint, the installation is convenient, and the installation space is saved. The two ends of the first coupling head 15 and the second coupling head 16 are made into elastic bayonet shapes, so that labor is saved and connection is facilitated.
Further, the first Rogowski coil 3 and the second Rogowski coil 4 are uniformly wound into a spiral shape by adopting enameled wires;
the shielding layer 17 is uniformly wound outside the first Rogowski coil 3 and the second Rogowski coil 4 by a conductive metal thin strip;
the outside of the shielding is provided with an insulating protective layer 18.
Specifically, since the current sensor 1 of the present application is a magnetic sensor, the current sensor 1 is in an electromagnetic environment when detecting. In order to ensure that the current sensor 1 can work normally and do not interfere with each other in the same electromagnetic environment, i.e. to improve the anti-electromagnetic interference capability of the current sensor 1, the shielding layer 17 is uniformly wound outside the first Rogowski coil 3 and the second Rogowski coil 4 by a conductive metal thin strip. The first coil end 8 and the shielding layer 17 at the same end are connected in series. The first coil end 8 and the shielding layer 17 at the same end are connected in series.
Further, the insulating plate 2 is an epoxy resin plate.
Specifically, the epoxy resin plate is an excellent insulating material having high dielectric properties, surface leakage resistance, and arc resistance, thereby ensuring the insulating properties of the insulating plate 2. The epoxy board has excellent mechanical properties, thereby ensuring that the first Rogowski coil 3 and the second Rogowski coil 4 are stably mounted on the insulating board 2. The epoxy resin plate has excellent alkali resistance, acid resistance and solvent resistance, thereby ensuring a longer service life of the insulating plate 2.
A monitoring system comprising said current sensor 1, an in-situ module 19, a remote module 20 and an optical fibre 21;
the current sensor 1 is electrically connected to the in-situ module 19;
the local module 19 is connected with the remote module 20 through the optical fiber 21;
the local module 19 comprises a data acquisition unit 22 and an electro-optical signal conversion unit 23;
the current sensor 1 is electrically connected with the electro-optical signal conversion unit 23 through the data acquisition unit 22;
the data acquisition unit 22 is connected with the optical fiber 21 through the electro-optical signal conversion unit 23;
the remote module 20 comprises a photoelectric signal conversion unit 24 and a data processing and analyzing unit 25;
the optical fiber 21 is electrically connected with the data processing and analyzing unit 25 through the photoelectric signal conversion unit 24.
Specifically, refer to fig. 7, which is a schematic structural diagram of a monitoring system according to an embodiment of the present application. The first signal lead 10 and the second signal lead 11 are directly connected to the local module 19, so that the current sensor 1 is electrically connected to the local module 19. Further, signals measured by the line at low current range at power frequency and high current range at high frequency are fed to the local module 19.
The optical fiber 21 has excellent electrical insulation property. The electrical signal output by the current sensor 1 is collected by the data collecting unit 22, is digitally modulated by the electro-optical signal converting unit 23 and then is locally converted into a digitized optical pulse signal, and is transmitted to the remote module 20 through the optical fiber 21, and the optical pulse signal is converted into an analog signal by the electro-optical signal converting unit and is processed and analyzed by the data processing and analyzing unit 25. The analysis result is used for parameter calculation, trend prediction, data storage, waveform display and the like of the current in the tested lead 6. The whole monitoring system with the current sensor 1 has high detection accuracy, and can effectively monitor the running state of a current loop; the system sensor is convenient to install and small in size; in addition, the optical fiber 21 is adopted for signal transmission, so that the monitoring system has excellent anti-electromagnetic interference capability, no extra error is introduced into the system, and the stability and reliability of the system are improved.
Further, the monitoring system also includes a non-metallic housing 26;
the current sensor 1, the in-situ module 19, the remote module 20 and the optical fiber 21 are enclosed inside the non-metallic housing 26.
In particular, the non-metallic housing 26 provides a closed, dry environment for the current sensor 1, the in-situ module 19, the remote module 20, the optical fiber 21, and the measured conductor 6, thereby ensuring reliable operation of the monitoring system.
As can be seen from the above technical solutions, the present application provides a current sensor, where the current sensor 1 includes an insulating plate 2, a first Rogowski coil 3, and a second Rogowski coil 4. The first Rogowski coil 3 is fixed to one side of the insulating plate 2 and the second Rogowski coil 4 is fixed to the other side of the insulating plate 2. The number of turns of said first Rogowski coil 3 is smaller than the number of turns of said second Rogowski coil 4. The current sensor can measure signals of a circuit in a small current range under power frequency and a large current range under high frequency. Therefore, the current sensor 1 avoids the problems that the conventional ferromagnetic current transformer is easy to saturate under the condition that primary current contains direct-current components due to the existence of an iron core when the measurement is carried out, the range of the measured current is reduced, the frequency band is narrow, and the picked-up signal is easy to distort. In the process of measuring the fault current with large amplitude, the magnetic saturation phenomenon can not occur, the linear characteristic is excellent, and the method is suitable for being applied to occasions with higher requirements on the current measurement precision. The application also provides a monitoring system comprising the current sensor to complete the monitoring process.
It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity from another entity without necessarily requiring or implying any actual such relationship or order between such entities. Moreover, other variations, such as the term "comprises" or "comprising," are intended to cover a non-exclusive inclusion, such that a device that comprises a list of elements does not include only those elements but may include other elements expressly listed or inherent to such device.
The embodiments provided in the present application are only a few examples of the general concept of the present application, and do not limit the scope of the present application. Any other embodiments extended according to the scheme of the present application without inventive efforts will be within the scope of protection of the present application for a person skilled in the art.
Claims (8)
1. A current sensor, characterized in that the current sensor (1) comprises an insulating plate (2), a first Rogowski coil (3) and a second Rogowski coil (4);
a through hole (5) is formed in the center of the insulating plate (2);
a lead (6) is arranged on the axis of the through hole (5);
the first Rogowski coil (3) is fixed on one surface of the insulating plate (2);
the second Rogowski coil (4) is fixed on the other surface of the insulating plate (2);
the number of turns of the first Rogowski coil (3) is smaller than the number of turns of the second Rogowski coil (4);
frameworks (7) with the same structure and size are arranged on the axes of the first Rogowski coil (3) and the second Rogowski coil (4);
one end of each of the first Rogowski coil (3) and the second Rogowski coil (4) is provided with a first coil end (8);
the other ends of the first Rogowski coil (3) and the second Rogowski coil (4) are provided with second coil end heads (9);
a first signal lead (10) is arranged on the first coil end (8);
the first signal lead (10) is connected with the first coil end (8);
a second signal lead (11) is arranged on the second coil end (9);
the second signal lead (11) is connected with the second coil end (9).
2. The current sensor according to claim 1, characterized in that the skeleton (7) consists of 4 rods (12);
the 4 round rods (12) are connected in a surrounding mode through the first Rogowski coil (3) and the second Rogowski coil (4) end to form a square structure.
3. The current sensor according to claim 2, characterized in that the insulating plate (2) comprises a first half-ring (13), a second half-ring (14), a first coupling head (15) and a second coupling head (16);
one end of the first half ring (13) is connected with one end of the second half ring (14) through the first coupling head (15);
the other end of the first half ring (13) is connected with the other end of the second half ring (14) through the second joint (16).
4. A current sensor according to claim 3, wherein said first coupling head (15) and said second coupling head (16) are plug-in coupling heads;
the two ends of the first coupling head (15) and the second coupling head (16) are in the shape of elastic bayonets.
5. The current sensor according to claim 1, characterized in that the first Rogowski coil (3) and the second Rogowski coil (4) are uniformly wound in a spiral shape using enameled wires;
the outer parts of the first Rogowski coil (3) and the second Rogowski coil (4) are uniformly wound with a shielding layer (17) by a conductive metal thin strip;
and an insulating protective layer (18) is arranged outside the shielding layer.
6. The current sensor according to claim 1, wherein the insulating plate (2) is an epoxy plate.
7. A monitoring system, characterized in that it comprises a current sensor (1) according to any one of claims 1 to 6, an in-situ module (19), a remote module (20) and an optical fiber (21);
the current sensor (1) is electrically connected with the in-situ module (19);
the local module (19) is connected with the remote module (20) through the optical fiber (21);
the local module (19) comprises a data acquisition unit (22) and an electro-optical signal conversion unit (23);
the current sensor (1) is electrically connected with the electro-optical signal conversion unit (23) through the data acquisition unit (22);
the data acquisition unit (22) is connected with the optical fiber (21) through the electro-optical signal conversion unit (23);
the remote module (20) comprises a photoelectric signal conversion unit (24) and a data processing and analyzing unit (25);
the optical fiber (21) is electrically connected with the data processing and analyzing unit (25) through the photoelectric signal conversion unit (24).
8. The monitoring system of claim 7, further comprising a non-metallic housing (26);
the current sensor (1), the in-situ module (19), the remote module (20) and the optical fiber (21) are enclosed inside the non-metallic housing (26).
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| Application Number | Priority Date | Filing Date | Title |
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| CN201820315826.0U CN207798899U (en) | 2018-03-08 | 2018-03-08 | A kind of current sensor and monitoring system |
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| CN201820315826.0U CN207798899U (en) | 2018-03-08 | 2018-03-08 | A kind of current sensor and monitoring system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108414798A (en) * | 2018-03-08 | 2018-08-17 | 云南电网有限责任公司电力科学研究院 | A kind of current sensor, monitoring system and monitoring method |
| CN113325265A (en) * | 2021-05-12 | 2021-08-31 | 武汉三相电力科技有限公司 | Device for detecting mixed traveling wave in power transmission line |
-
2018
- 2018-03-08 CN CN201820315826.0U patent/CN207798899U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108414798A (en) * | 2018-03-08 | 2018-08-17 | 云南电网有限责任公司电力科学研究院 | A kind of current sensor, monitoring system and monitoring method |
| CN113325265A (en) * | 2021-05-12 | 2021-08-31 | 武汉三相电力科技有限公司 | Device for detecting mixed traveling wave in power transmission line |
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