Low-power current optical sensor

Abstract

The invention relates to the technical field of mutual inductors, and discloses a low-power current optical sensor which comprises a shell, an installation cavity is formed in the shell, a polarizer and an analyzer are fixedly installed in the installation cavity, a conversion wheel is rotatably installed in the installation cavity, and multiple sets of magneto-optic glass are fixedly installed on the surface of the conversion wheel. The multiple sets of magneto-optic glass are arranged on the outer circle face of the conversion wheel in an annular array mode, and the lengths of the multiple sets of magneto-optic glass are different. According to the current optical sensor provided by the invention, the rotatable conversion wheel is arranged in the shell of the sensor, and the surface of the conversion wheel is provided with multiple groups of magneto-optic glass with different lengths, so that in the use process, the positions of the magneto-optic glass are switched, and light rays emitted by the polarizer pass through the magneto-optic glass with different lengths and then reach the polarization analyzer; therefore, the response amplitude is adjusted, the response sensitivity of the sensor and the signal-to-noise ratio of the system are improved, the sensor can be adjusted according to different detection objects, and the applicability of the sensor is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of instrument transformers, and particularly to a low-power current optical sensor. Background Art

[0002] Electromagnetic current transformers have disadvantages such as being prone to magnetic saturation under overcurrent, having an insufficiently wide passband, and the remanence having a large impact on the transient error of the CT. Optical current sensors are a type of instrument transformer based on the Faraday magneto-optical effect, and their good electrical insulation performance, excellent radiation resistance, extremely fast frequency response, etc. provide great potential possibilities for their application in the power system.

[0003] In order to solve the problem of temperature drift in the measurement accuracy of current optical current transformers, in the prior art, a patent document with the publication number CN102495260B discloses a temperature drift compensation optical current transformer and its current compensation method, including a solenoid self-inductance sensor. The optical sensor is connected to the solenoid self-inductance sensor through polarization-maintaining optical fibers. The solenoid self-inductance sensor is connected to the signal processing unit through multimode optical fibers. The signal processing unit is connected to the optical sensor through multimode optical fibers. Temperature drift current compensation method: Express the Faraday rotation angle generated by the linearly polarized light of the optical sensor through the measured current; Express the Faraday rotation angle generated by the linearly polarized light of the solenoid self-inductance sensor through the compensation current; The output voltage expression can be derived according to the expression of the rotation angle; It is proved that the measurement of the primary current is realized.

[0004] According to the Faraday magneto-optical effect, when linearly polarized light propagates in a medium, if a strong magnetic field is applied in the direction parallel to the light propagation direction, the direction of light vibration will deflect. The deflection angle ψ is proportional to the product of the magnetic induction intensity B and the length L of the light passing through the medium, that is, ψ = VBL, and the proportionality coefficient V is called the Verdet constant; If the magnetic field is caused by an alternating current, then ψ can be further expressed as ψ = ψ0sin(ωt), where ψ0 is the modulation amplitude of the Faraday rotation angle.

[0005] According to Malus' law, I2 = I1cos 2 θ, where I2 is the light intensity of the incident linearly polarized light, I1 is the light intensity of the transmitted light (without considering the absorption of the transmitted light by the analyzer), and θ is the included angle between the transmission axes of the polarizer and the analyzer; By measuring I2, the alternating current i(t) = sin(ωt) in the generated magnetic field can be indirectly measured, which is the basic principle of the optical current sensor.

[0006] See reference: Lin Sen, Du Mingming, Wang Shibin. Research on the response characteristics of an optical current sensor based on MR3-2 magneto-optical glass [J]. Electrical Application, 2016, 35(15): 70-74. By increasing the magnetic field strength B and / or the length L of the light passing through the medium, the response amplitude can be improved, thereby enhancing the response sensitivity of the sensor and the signal-to-noise ratio of the system. During the actual detection process, with a certain measured current and a constant magnetic field strength B, and the length L of the light passing through the medium in the existing optical current sensors being fixed, the response amplitude cannot be adjusted under different detection scenarios, greatly reducing the applicability of the optical current sensors. Summary of the Invention

[0007] The purpose of the present invention is to solve the problem in the prior art that due to the fact that the length L of the light passing through the medium in the existing optical current sensors cannot be adjusted as needed, the application scenarios are limited, and a low-power current optical sensor is proposed.

[0008] To achieve the above purpose, the present invention adopts the following technical solution: A low-power current optical sensor includes a housing. An installation cavity is provided inside the housing. A polarizer and an analyzer are respectively fixedly installed inside the installation cavity. A conversion wheel is rotatably installed inside the installation cavity. Multiple groups of magneto-optical glasses are fixedly installed on the surface of the conversion wheel. The multiple groups of magneto-optical glasses are arranged in a circular array on the outer circumferential surface of the conversion wheel. The lengths of the multiple groups of magneto-optical glasses are different. The polarizer and the analyzer are arranged opposite to each other. When the conversion wheel rotates, each magneto-optical glass respectively rotates to the area formed between the polarizer and the analyzer. A driving mechanism is provided inside the housing, and the conversion wheel is driven by the driving mechanism to rotate at a fixed angle, thereby adjusting the response amplitude and enhancing the response sensitivity of the sensor and the signal-to-noise ratio of the system.

[0009] Preferably, the installation cavity is a vacuum cavity. A connecting shaft is fixedly installed at the axis center of the conversion wheel. Both ends of the connecting shaft are rotatably connected to the end faces at both ends of the installation cavity. Each group of magneto-optical glasses includes a first glass block and a second glass block. The cross-sections and lengths of the first glass block and the second glass block are equal. A number of first glass blocks and second glass blocks are arranged alternately and fixedly installed on the surface of the conversion wheel.

[0010] Preferably, the Verdet constants of the first glass block and the second glass block are different. At different temperatures, the response wave amplitude characteristic curve of the first glass block is known as the first curve, and the response wave amplitude characteristic curve of the second glass block is known as the second curve.

[0011] The low-power current optical sensor measures the wire to be measured. By driving the conversion wheel to rotate, the angles of each group of magneto-optical glasses are switched, so that each first glass block and the second glass block are sequentially rotated to the area formed between the polarizer and the analyzer. When the incident light intensity is certain, the deflection angles ψ of each group of magneto-optical glasses are measured respectively, and the average current value of the wire to be measured is calculated. It is possible to select an appropriate rotation angle for measurement and calculation by switching magneto-optical glasses with different magneto-optical medium lengths and Verdet constants, which expands the detection range of the sensor.

[0012] Preferably, the low-power current optical sensor measures the wire to be measured. By driving the conversion wheel to rotate, the angles of each group of magneto-optical glasses are switched, so that the second glass block is rotated to the area formed between the polarizer and the analyzer. When the incident light intensity is certain, at least two response amplitudes Vx of the second glass block are actually measured. The simulation amplitude characteristic curve drawn from the actually measured response amplitude Vx of the second glass block is the third curve. Among them, a second curve with the same slope as the third curve is selected as the compensation curve, and the current value of the wire to be measured is obtained according to the compensation curve. This design realizes representing the current to be measured by the current value corresponding to the second curve, compensates for the influence of temperature on the actual measurement result, and solves the problem that temperature change affects the measurement accuracy.

[0013] Preferably, the driving mechanism includes an adjusting disk. A sealed cavity is opened inside the housing. The adjusting disk is rotatably arranged in the sealed cavity. The connecting shaft extends into the sealed cavity and is fixedly connected to the adjusting disk. It also includes a servo motor and a driving disk. The servo motor is fixedly installed in the housing. The driving disk is fixedly installed at the rotating end of the servo motor, and the driving disk is located outside the sealed cavity. A number of magnetic blocks are embedded in the opposite surfaces of the driving disk and the adjusting disk. The driving disk and the adjusting disk are magnetically adsorbed to each other through the magnetic blocks. A battery pack for supplying electric energy to the servo motor is arranged in the housing.

[0014] A clamp is installed on the upper side of the housing through bolts, and the housing is fixedly installed on the surface of the wire to be measured through the clamp. This current optical sensor does not need to be provided with a constant temperature control mechanism, which reduces its power and energy consumption.

[0015] The present invention has the following beneficial effects:

[0016] 1. The low-power current optical sensor proposed by the present invention, by arranging a rotatable conversion wheel inside the housing of the sensor, and multiple groups of magneto-optical glasses with different lengths are arranged on the surface of the conversion wheel. During use, the positions of the magneto-optical glasses are switched, so that the light emitted by the polarizer passes through magneto-optical glasses with different lengths and then reaches the analyzer, thereby adjusting the response amplitude, improving the response sensitivity of the sensor and the signal-to-noise ratio of the system, enabling the sensor to be adjusted according to different detection objects, and greatly improving its applicability.

[0017] 2. The low-power current optical sensor proposed by the present invention sets a first glass block and a second glass block with different Verdet constants. Each group of magneto-optical glasses includes a first glass block and a second glass block. When light passes through the magneto-optical medium, the polarization direction rotates, and the rotation angle depends on the length of the magneto-optical medium and the Verdet constant. When the magnetic field strength measured by the sensor varies within a relatively wide range, different magneto-optical glasses with different lengths of magneto-optical media and Verdet constants can be switched to select an appropriate rotation angle for measurement and calculation, thus expanding the detection range of the sensor.

[0018] 3. The low-power current optical sensor proposed by the present invention sets the MR3-2 new type of magneto-optical glass as the second glass block. The amplitude characteristic curve of the MR3-2 new type of magneto-optical glass is a straight line, and the slope of the straight line can be used to measure the magnitude of its response amplitude. Moreover, the change rate of its response amplitude with temperature is basically the same. Utilizing the sensitivity of the second glass block to temperature, before use, the second curve at different temperatures is measured for the second glass block under ideal laboratory conditions. During use, the third curve of the second glass block is obtained through actual measurement. The current value of the wire to be measured is obtained from the second curve with the same slope as the slope of the third curve. This design realizes representing the current to be measured by the current value corresponding to the second curve, compensating for the influence of temperature on the actual measurement result, and solving the problem that temperature changes affect the measurement accuracy. This current optical sensor does not need to set a constant temperature control mechanism, reducing its power and energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a partial cross-sectional three-dimensional structure schematic diagram of the current optical sensor proposed by the present invention;

[0020] Figure 2 is a three-dimensional structure schematic diagram of the conversion wheel proposed by the present invention;

[0021] Figure 3 is a front cross-sectional structure schematic diagram of the current optical sensor proposed by the present invention;

[0022] Figure 4 is a schematic diagram of the principle of the Faraday magneto-optical effect;

[0023] Figure 5 is a schematic diagram of the first curve of the response wave amplitude characteristic;

[0024] Figure 6 is a schematic diagram of the second curve of the response wave amplitude characteristic Figure 1 ;

[0025] Figure 7 is a schematic diagram of the second curve of the response wave amplitude characteristic Figure 2 。

[0026] In the figure: 1, housing; 2, installation cavity; 3, conversion wheel; 4, magneto-optical glass; 5, polarizer; 6, analyzer; 7, connecting shaft; 8, first glass block; 9, second glass block; 10, first curve; 11, second curve; 12, wire to be measured; 13, adjusting disk; 14, servo motor; 15, driving disk; 16, magnetic block; 17, clamp; 18, third curve. Specific embodiments

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0028] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0029] Refer to Figures 1 - 7 , a low-power current optical sensor, including a housing 1. An installation cavity 2 is opened inside the housing 1. A polarizer 5 and an analyzer 6 are respectively fixedly installed inside the installation cavity 2. The laser is connected to the polarizer 5 through an optical fiber, and the analyzer 6 is connected to an optoelectronic probe through an optical fiber. The electrical signal generated by the optoelectronic probe is processed by a data acquisition card and imported into a computer. This belongs to a conventional setting and will not be elaborated here. A conversion wheel 3 is rotatably installed inside the installation cavity 2. Specifically, the installation cavity 2 is a vacuum cavity. A connecting shaft 7 is fixedly installed at the axis center of the conversion wheel 3, and both ends of the connecting shaft 7 are rotatably connected to the end faces at both ends of the installation cavity 2.

[0030] As Figure 2 shown, multiple groups of magneto-optical glass 4 are fixedly installed on the surface of the conversion wheel 3. The multiple groups of magneto-optical glass 4 are arranged in a circular array on the outer circular surface of the conversion wheel 3. The lengths of the multiple groups of magneto-optical glass 4 are different. As Figure 2 shown, the lengths of the multiple groups of magneto-optical glass 4 increase in sequence. The polarizer 5 and the analyzer 6 are arranged opposite to each other. When the conversion wheel 3 rotates, each magneto-optical glass 4 respectively rotates to the area formed between the polarizer 5 and the analyzer 6. The polarized light emitted by the polarizer 5 passes through the magneto-optical glass 4 and then reaches the analyzer 6. The vacuum cavity can ensure the propagation of light between the polarizer 5 and the analyzer 6, reduce scattering, and at the same time reduce the influence of the external temperature on the magneto-optical glass 4.

[0031] A clamp 17 is installed on the upper side of the housing 1 through bolts, and the housing 1 is fixedly installed on the surface of the wire 12 to be measured through the clamp 17. A driving mechanism is arranged inside the housing 1, and the driving mechanism drives the conversion wheel 3 to rotate at a fixed angle. Among them, the driving mechanism includes an adjusting disk 13. A sealing cavity is formed inside the housing 1, and the adjusting disk 13 is rotatably arranged in the sealing cavity. The connecting shaft 7 extends into the sealing cavity and is fixedly connected to the adjusting disk 13.

[0032] The driving mechanism further includes a servo motor 14 and a driving disk 15. The servo motor 14 is fixedly installed inside the housing 1, and the driving disk 15 is fixedly installed at the rotating end of the servo motor 14. And the driving disk 15 is located outside the sealing cavity. A number of magnetic blocks 16 are embedded in the opposite surfaces of the driving disk 15 and the adjusting disk 13, as Figure 3 shown. The driving disk 15 and the adjusting disk 13 are magnetically attracted to each other through the magnetic blocks 16. A power storage pack for supplying electric energy to the servo motor 14 is arranged inside the housing 1. The servo motor 14 rotates to drive the conversion wheel 3 to rotate at a fixed angle or switch its rotation direction.

[0033] In this embodiment, each group of magneto-optical glasses 4 includes a first glass block 8 and a second glass block 9. The cross-sections and lengths of the first glass block 8 and the second glass block 9 are equal. A number of first glass blocks 8 and second glass blocks 9 are arranged alternately and fixedly installed on the surface of the conversion wheel 3, as Figure 2 shown.

[0034] The Verdet constants of the first glass block 8 and the second glass block 9 are different. The Verdet constant of the magneto-optical glass 4 is related to the characteristics of the medium, the wavelength of the light source, the external temperature, etc. The Verdet constants of each first glass block 8 and second glass block 9 are detected through experiments. The specific measurement method can be found in the reference: Zhang Guangtai, Wu Fuquan, Xu Liguo, etc. Precise measurement of the Verdet constant of magneto-optical glass [J]. Laser Journal, 2013, 34(01): 48-49. The Verdet constants of the first glass block 8 and the second glass block 9 are known.

[0035] According to the Faraday magneto-optical effect, when linearly polarized light propagates in a medium, if a strong magnetic field is applied in the direction parallel to the light propagation direction, the direction of light vibration will deflect. The deflection angle ψ is proportional to the product of the magnetic induction intensity B and the length L of the light passing through the medium, that is, ψ = VBL. The proportionality coefficient V is called the Verdet constant, as Figure 4 shown;

[0036] When the current optical sensor measures the current of the wire 12 to be measured, the magnetic induction intensity B is caused by the wire 12 to be measured. Then ψ can be further expressed as ψ = ψ0sin(ωt), where ψ0 is the modulation amplitude of the Faraday rotation angle;

[0037] According to Malus' law, I2 = I1cos 2 θ, where I2 is the light intensity of the incident linearly polarized light, I1 is the light intensity of the transmitted light (ignoring the absorption of the transmitted light by the analyzer 6), and θ is the angle between the transmission axes of the polarizer and the analyzer; by measuring I2, the alternating current i(t) = sin(ωt) in the generated magnetic field can be indirectly measured. This is the basic principle of the optical current sensor and belongs to common knowledge, so it will not be elaborated here.

[0038] When this current optical sensor measures the current of the wire 12 to be measured, according to the Faraday magneto-optical effect, with the magnetic induction intensity B and Verdet constant being certain, increasing the length L of the light passing through the medium, that is, increasing the length of the magneto-optical glass 4, can improve the response amplitude, thereby achieving the effect of improving the response sensitivity and the signal-to-noise ratio of the system.

[0039] The low-power current optical sensor proposed by the present invention is provided with a rotatable conversion wheel 3 in the housing 1 of the sensor. Multiple groups of magneto-optical glasses 4 with different lengths are arranged on the surface of the conversion wheel 3. During use, the position of the magneto-optical glass 4 is switched, so that the light emitted by the polarizer 5 passes through the magneto-optical glasses 4 with different lengths and then reaches the analyzer 6, thereby adjusting the response amplitude, improving the response sensitivity of the sensor and the signal-to-noise ratio of the system, enabling the sensor to be adjusted according to different detection objects, and greatly improving its applicability.

[0040] This current optical sensor measures the wire 12 to be measured. By driving the conversion wheel 3 to rotate and switching the angles of the magneto-optical glasses 4 in each group, the first glass blocks 8 and the second glass blocks 9 are sequentially rotated to the area formed between the polarizer 5 and the analyzer 6. When ensuring a certain incident light intensity, the deflection angles ψ of the magneto-optical glasses 4 in each group are measured respectively, and the average current of the wire 12 to be measured is calculated.

[0041] By setting the first glass blocks 8 and the second glass blocks 9 with different Verdet constants, each group of magneto-optical glasses 4 includes the first glass blocks 8 and the second glass blocks 9. The polarization direction of the light passing through the magneto-optical medium rotates, and its rotation angle depends on the length of the magneto-optical medium and the Verdet constant. When the magnetic field intensity measured by this sensor has a relatively wide change range, different magneto-optical glasses 4 with different lengths of the magneto-optical medium and Verdet constants can be switched to select a suitable rotation angle for measurement and calculation, expanding the detection range of the sensor.

[0042] In this embodiment, the second glass block 9 adopts the new type of magneto-optical glass MR3-2. Through the Faraday magneto-optical effect experimental platform, the response characteristics of the first glass block 8 and the second glass block 9 under alternating sinusoidal excitation are experimentally studied. The response characteristics include: response waveform, amplitude characteristics, frequency characteristics, and temperature characteristics. After measurement, at different temperatures, the amplitude characteristic curve of the response wave of the first glass block 8 is known, which is the first curve 10, asFigure 5 As shown in the reference: Lin Sen, Du Lin, Wang Shibin, etc. Research on Electrical Characteristics of Optical Current Sensor Based on Faraday Magneto - optical Effect [J]. Chinese Journal of Sensors and Actuators, 2010, 23(04): 490 - 495; The response wave amplitude characteristic curve of the second glass block 9 is known, which is the second curve 11. As Figure 6 shown in the reference: Lin Sen, Du Mingming, Wang Shibin. Research on Response Characteristics of Optical Current Sensor Based on MR3 - 2 Magneto - optical Glass [J]. Electrical Application, 2016, 35(15): 70 - 74.

[0043] This current optical sensor measures the wire 12 to be measured. By driving the conversion wheel 3 to rotate, the angles of each group of magneto - optical glasses 4 are switched, so that the second glass block 9 is rotated to the area formed between the polarizer 5 and the analyzer 6. When ensuring a certain incident light intensity, at least two response amplitudes Vx of the second glass block 9 are obtained through actual measurement. The simulated amplitude characteristic curve drawn from the actually measured response amplitude Vx of the second glass block 9 is the third curve 18. As Figure 7 shown, the amplitude characteristic curve of the new MR3 - 2 magneto - optical glass is a straight line, and the slope of the straight line can be used to measure the magnitude of its response amplitude. Moreover, the change rate of its response amplitude with temperature is basically the same. Among them, the second curve 11 with the same slope as the third curve 18 is selected as the compensation curve. According to the compensation curve, the current value of the wire 12 to be measured is obtained, that is, the current value I4 of the wire 12 to be measured is obtained from the second curve 11 with the same slope as the third curve 18. Affected by temperature, the current value I3 of the wire 12 to be measured is actually measured through the second glass block 9. There is an error between the current value I3 and the current value I4, which is caused by the change of the Verdet coefficient due to temperature. Since the current value I4 is measured in the temperature - controlled environment in the laboratory, it can more truly reflect the magnitude of the current to be measured and has higher accuracy.

[0044] The low - power current optical sensor proposed by the present invention sets the new MR3 - 2 magneto - optical glass as the second glass block 9. The amplitude characteristic curve of the new MR3 - 2 magneto - optical glass is a straight line, and the slope of the straight line can be used to measure the magnitude of its response amplitude. Moreover, the change rate of its response amplitude with temperature is basically the same. Utilizing the temperature sensitivity of the second glass block 9, before use, the second curve 11 at different temperatures of the second glass block 9 is measured under ideal laboratory conditions. During use, the third curve 18 of the second glass block 9 is obtained through actual measurement. The current value of the wire 12 to be measured is obtained from the second curve 11 with the same slope as the third curve 18. This design realizes representing the current to be measured by the current value corresponding to the second curve 11, compensating for the influence of temperature on the actual measurement result, and solving the problem that temperature change affects the measurement accuracy. This current optical sensor does not need to set a constant - temperature control mechanism, reducing its power and energy consumption.

[0045] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, shall be covered by the protection scope of the present invention.

Claims

1. A low-power current optical sensor, comprising a housing (1), characterized in that: An installation cavity (2) is formed inside the housing (1). Inside the installation cavity (2), a polarizer (5) and an analyzer (6) are fixedly installed respectively. A conversion wheel (3) is rotatably installed inside the installation cavity (2). A plurality of magneto-optical glasses (4) are fixedly installed on the surface of the conversion wheel (3). The plurality of magneto-optical glasses (4) are arranged in a circular array on the outer circular surface of the conversion wheel (3). The lengths of the plurality of magneto-optical glasses (4) are different. The polarizer (5) and the analyzer (6) are arranged opposite to each other. When the conversion wheel (3) rotates, each magneto-optical glass (4) rotates to the area formed between the polarizer (5) and the analyzer (6). A driving mechanism is arranged inside the housing (1), and the conversion wheel (3) is driven by the driving mechanism to rotate at a fixed angle.

2. The low-power current optical sensor according to claim 1, wherein: The installation cavity (2) is a vacuum cavity. A connecting shaft (7) is fixedly installed at the axis center of the conversion wheel (3). Both ends of the connecting shaft (7) are rotatably connected to the end faces of both ends of the installation cavity (2).

3. The low-power current optical sensor according to claim 2, wherein: Each group of the magneto-optical glasses (4) includes a first glass block (8) and a second glass block (9). The cross-sections and lengths of the first glass block (8) and the second glass block (9) are equal. A plurality of first glass blocks (8) and second glass blocks (9) are arranged alternately and fixedly installed on the surface of the conversion wheel (3).

4. The low-power current optical sensor according to claim 3, characterized in that: The Verdet constants of the first glass block (8) and the second glass block (9) are different. At different temperatures, the response wave amplitude characteristic curve of the first glass block (8) is known, which is the first curve (10), and the response wave amplitude characteristic curve of the second glass block (9) is known, which is the second curve (11).

5. The low-power current optical sensor according to claim 4, wherein: The low-power current optical sensor measures the wire under test (12). By driving the conversion wheel (3) to rotate and switching the angles of each group of magneto-optical glasses (4), each first glass block (8) and second glass block (9) are sequentially rotated to the area formed between the polarizer (5) and the analyzer (6). When the incident light intensity is kept constant, the deflection angles ψ of each group of magneto-optical glasses (4) are measured respectively, and the average current value of the wire under test (12) is calculated.

6. The low-power current optical sensor according to claim 4, wherein: The low-power current optical sensor measures the wire under test (12). By driving the conversion wheel (3) to rotate and switching the angles of each group of magneto-optical glasses (4), the second glass block (9) is rotated to the area formed between the polarizer (5) and the analyzer (6). When the incident light intensity is kept constant, at least two response amplitudes Vx of the second glass block (9) are actually measured. The simulated amplitude characteristic curve drawn from the actually measured response amplitude Vx of the second glass block 9 is the third curve (18). Among them, the second curve (11) with the same slope as the third curve (18) is selected as the compensation curve, and the current value of the wire under test (12) is obtained according to the compensation curve.

7. A low-power current optical sensor according to claim 6, characterized in that: The driving mechanism includes an adjusting disc (13). A sealing cavity is formed inside the housing (1). The adjusting disc (13) is rotatably arranged in the sealing cavity. The connecting shaft (7) extends into the sealing cavity and is fixedly connected to the adjusting disc (13).

8. An optical current sensor with low power consumption according to claim 7, characterized in that: The driving mechanism further includes a servo motor (14) and a driving disk (15). The servo motor (14) is fixedly installed inside the housing (1). The driving disk (15) is fixedly installed at the rotating end of the servo motor (14), and the driving disk (15) is located outside the sealing cavity. A plurality of magnetic blocks (16) are embedded in the opposite surfaces of the driving disk (15) and the adjusting disk (13). The driving disk (15) and the adjusting disk (13) are magnetically attracted to each other through the magnetic blocks (16). A storage battery pack for supplying electric energy to the servo motor (14) is arranged inside the housing (1).

9. A low-power current optical sensor according to any one of claims 1-8, characterized in that: A clamp (17) is installed on the upper side of the housing (1) through bolts, and the housing (1) is fixedly installed on the surface of the wire under test (12) through the clamp (17).

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