Current transformer with temperature compensation function and compensation method thereof

Abstract

The application discloses a current transformer with a temperature compensation function and a compensation method thereof, and comprises a fiber sensing ring, a collection module, a temperature detection module and a temperature compensation module; wherein the current collection module is used for being connected to the fiber sensing ring, generating an optical signal into the fiber sensing ring, and performing photoelectric conversion and signal processing on an optical signal generated by the fiber sensing ring under the action of a current to be measured to obtain a current induction signal; the temperature detection module is used for detecting a temperature signal of the fiber sensing ring; and the temperature compensation module is used for determining a temperature compensation coefficient based on the temperature signal and performing temperature compensation processing on the current induction signal based on the temperature compensation coefficient. The accuracy of temperature detection is improved, and the accuracy of temperature compensation is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of current transformers, in particular to a current transformer with temperature compensation function and a compensation method thereof. BACKGROUND

[0002] At present, the traditional electromagnetic current transformer has problems of ferromagnetic saturation, direct current component measurement and high voltage insulation, which affects the safe and stable operation of the power grid. In recent years, various forms of new electronic current transformers have been developed, among which the all-optical direct current transformer indirectly measures the primary current based on the Faraday magneto-optical effect. The measurement principle is that when the polarized light signal is transmitted in the high-voltage side sensing optical fiber, the polarization state will change under the influence of the magnetic field, and the change is related to the number of sensing optical fiber turns, the size of the magnetic field and the Verdet constant. Among them, the Verdet constant is affected by the center wavelength of the light signal and the refractive index of the sensing optical fiber. At present, the working temperature and working current of the SLD light source are controlled in the all-optical current transformer, and the center wavelength of the light source is basically unchanged, but the degradation of the measurement performance caused by the change of the environmental temperature of the sensing optical fiber cannot be controlled, which affects its popularization and application in the field of high-precision measurement.

[0003] In the prior art, a temperature sensor is used to collect the external environmental temperature and return it to the control unit in digital form. The control unit corrects the measurement output according to the actual environmental temperature and the sensing optical fiber temperature curve stored in the register to compensate for the measurement deviation of the direct current all-optical current transformer caused by the change of the environmental temperature. However, due to the defects of the in-situ placement scheme of the temperature sensor, there is a deviation between the actual working temperature of the sensing optical fiber and the temperature collected by the temperature sensor, resulting in inaccurate temperature compensation. SUMMARY

[0004] The present application aims to at least one of the above technical problems in the technical field. To this end, the present application aims to provide a current transformer with temperature compensation function and a compensation method thereof, to improve the accuracy of temperature detection and thus improve the accuracy of temperature compensation.

[0005] To achieve the above-mentioned purpose, the present application provides a current transformer with temperature compensation function, comprising: an optical fiber sensing ring, an acquisition module, a temperature detection module, a temperature compensation module; wherein,

[0006] The current acquisition module is used to connect to the optical fiber sensing ring, generate an optical signal into the optical fiber sensing ring, and perform photoelectric conversion and signal processing on the optical signal generated by the optical fiber sensing ring under the action of the measured current to obtain a current sensing signal;

[0007] The temperature detection module is used to detect the temperature signal of the optical fiber sensing ring;

[0008] The temperature compensation module is configured to determine a temperature compensation coefficient based on the temperature signal, and perform temperature compensation processing on the current induction signal based on the temperature compensation coefficient.

[0009] According to some embodiments of the present application, the temperature detection module comprises a light source, a polarizer, a first splitting point, a modulator, a second splitting point, an analyzer, a detector and a demodulator, wherein,

[0010] The light source emits a light signal, the polarizer converts the light signal into two linearly polarized lights, at the first splitting point, the two linearly polarized lights are split into two linearly polarized lights perpendicular to each other, the two linearly polarized lights perpendicular to each other are subjected to initial phase modulation by the modulator, and are transmitted along the fast axis and the slow axis of the polarization maintaining optical fiber;

[0011] After passing through the second splitting point, the linearly polarized lights on the fast axis and the slow axis are split into two linearly polarized lights perpendicular to each other again; the analyzer only allows the two linearly polarized lights on one axis to pass through, and the light on the other axis is filtered; through the feedback phase adjustment of the modulator, the two linearly polarized lights have a specific phase difference when returning to the analyzer and interfere; the detector converts the interference light signal into an electric signal; the demodulator demodulates the temperature signal from the electric signal to determine the temperature signal of the optical fiber sensing ring.

[0012] According to some embodiments of the present application, the temperature compensation module comprises a ceramic heating sheet, the ceramic heating sheet is powered, and the ceramic heating sheet gradually heats up and heats the optical fiber sensing ring.

[0013] According to some embodiments of the present application, the temperature compensation module comprises two heating solenoids with opposite winding directions, for generating two magnetic fields with the same size and opposite directions, and the heating solenoids are placed equidistantly on both sides of the temperature detection module.

[0014] According to some embodiments of the present application, further comprising: a state detection module configured to:

[0015] detect a first angular velocity and a first acceleration of the temperature detection module;

[0016] determine a first angular velocity matrix according to the first angular velocity, and determine a first acceleration matrix according to the first acceleration;

[0017] detect a second angular velocity and a second acceleration of the temperature detection module when the temperature detection module is in a stationary state;

[0018] determine a second angular velocity matrix according to the second angular velocity, and determine a second acceleration matrix according to the second acceleration;

[0019] subtract the first angular velocity matrix from the second angular velocity matrix to obtain a third angular velocity matrix, determine a maximum value in the third angular velocity matrix, and judge whether the maximum value is less than 0 to obtain a first comparison result;

[0020] Subtract the first acceleration matrix from the second acceleration matrix to obtain the third acceleration matrix. Determine the maximum value in the third acceleration matrix and check if it is less than 0 to obtain the second comparison result.

[0021] If the first comparison result is that the maximum value in the third angular velocity matrix is ​​less than 0 and the second comparison result is that the maximum value in the third acceleration matrix is ​​less than 0, it indicates that the temperature detection module is in a stationary state; otherwise, the temperature detection module is in a moving state.

[0022] When the temperature detection module is determined to be in motion, the first variance corresponding to the third angular velocity matrix and the second variance corresponding to the third acceleration matrix are calculated. Based on the first and second variances, the preset motion compensation coefficient table is consulted to obtain the motion compensation coefficient. The acquired temperature signal is then corrected based on the motion compensation coefficient to obtain the corrected temperature signal.

[0023] According to some embodiments of the present invention, the state detection module determines a first angular velocity matrix based on a first angular velocity and a first acceleration matrix based on a first acceleration, including:

[0024] Construct the first angular velocity vector ω=( , , );in, , , These are the angular velocity components in the x, y, and z directions, respectively;

[0025] The first angular velocity matrix is ​​represented as:

[0026]

[0027] in, This is the first angular velocity matrix;

[0028] Construct the first acceleration vector a=( , , ),in, , , These are the acceleration components in the x, y, and z directions, respectively;

[0029] The first acceleration matrix is ​​represented as:

[0030]

[0031] in, This is the first acceleration matrix.

[0032] According to some embodiments of the present invention, it further includes: a verification module, used to verify the temperature compensation processing result, and when it is determined that the verification fails, to regenerate the temperature compensation instruction to the temperature compensation module.

[0033] According to some embodiments of the present invention, the temperature compensation module includes:

[0034] The determination module is used for:

[0035] Based on several temperature signals, a preset temperature database is queried to determine the temperature compensation scheme corresponding to the several temperature signals, and the error parameters of the temperature compensation scheme are calculated.

[0036]

[0037] in, These are the error parameters for the temperature compensation scheme; This refers to the number of initial temperature compensation coefficients included in the temperature compensation scheme. The first temperature compensation scheme An initial temperature compensation coefficient;

[0038] Calculate the first reliability coefficient of the temperature compensation scheme. :

[0039]

[0040] in, It is a natural constant;

[0041] Calculate the second reliability coefficient of the temperature compensation scheme. :

[0042]

[0043] in, The first temperature compensation scheme A number;

[0044] Calculate the average of the first reliability coefficient and the second reliability coefficient. When the average value is determined to be greater than the preset threshold, the average value of several initial temperature compensation coefficients included in the temperature compensation scheme is taken as the temperature compensation coefficient.

[0045] The compensation module is used to perform temperature compensation processing on the current sensing signal based on the temperature compensation coefficient.

[0046] According to some embodiments of the present invention, a compensation method for a current transformer with temperature compensation function includes:

[0047] The current acquisition module is connected to the fiber optic sensing ring to generate an optical signal that enters the fiber optic sensing ring. The optical signal generated by the fiber optic sensing ring under the action of the current to be measured is converted into a photoelectric signal and processed to obtain the current sensing signal.

[0048] Temperature signals from the fiber optic sensing ring are detected using a temperature detection module.

[0049] The temperature compensation module determines the temperature compensation coefficient based on the temperature signal, and performs temperature compensation processing on the current sensing signal based on the temperature compensation coefficient.

[0050] According to some embodiments of the present invention, the temperature compensation module determines a temperature compensation coefficient based on a temperature signal, and performs temperature compensation processing on the current sensing signal based on the temperature compensation coefficient, including:

[0051] Based on several temperature signals, a preset temperature database is queried to determine the temperature compensation scheme corresponding to the several temperature signals, and the error parameters of the temperature compensation scheme are calculated.

[0052]

[0053] in, These are the error parameters for the temperature compensation scheme; This refers to the number of initial temperature compensation coefficients included in the temperature compensation scheme. The first temperature compensation scheme An initial temperature compensation coefficient;

[0054] Calculate the first reliability coefficient of the temperature compensation scheme. :

[0055]

[0056] in, It is a natural constant;

[0057] Calculate the second reliability coefficient of the temperature compensation scheme. :

[0058]

[0059] in, The first temperature compensation scheme A number;

[0060] Calculate the average of the first reliability coefficient and the second reliability coefficient. When the average value is determined to be greater than the preset threshold, the average value of several initial temperature compensation coefficients included in the temperature compensation scheme is taken as the temperature compensation coefficient.

[0061] Temperature compensation processing is performed on the current sensing signal based on the temperature compensation coefficient.

[0062] The application provides a current transformer with a temperature compensation function and a compensation method thereof.

[0063] Additional features and advantages of the application will be set forth in the description that follows, and in part will be apparent from the description, or can be learned by practice of the application. The objectives and other advantages of the application will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

[0064] The technical solutions of the application are described in detail below with reference to the drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0065] The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

[0066] Figure 1 is a block diagram of a current transformer with a temperature compensation function according to an embodiment of the application;

[0067] Figure 2 is a flowchart of a compensation method of a current transformer with a temperature compensation function according to an embodiment of the application. DETAILED DESCRIPTION

[0068] The preferred embodiments of the application are described below in detail with reference to the drawings. It should be understood that the preferred embodiments described herein are only used to explain and illustrate the application, and do not limit the application.

[0069] As shown in Figure 1 , the embodiment of the application provides a current transformer with a temperature compensation function, comprising: a fiber sensing ring, an acquisition module, a temperature detection module, and a temperature compensation module; wherein,

[0070] The current acquisition module is used to connect to the fiber sensing ring, generate an optical signal into the fiber sensing ring, and perform photoelectric conversion and signal processing on the optical signal generated by the fiber sensing ring under the action of the current to be measured to obtain a current sensing signal;

[0071] The temperature detection module is used to detect the temperature signal of the fiber sensing ring;

[0072] The temperature compensation module is used to determine a temperature compensation coefficient based on the temperature signal, and perform temperature compensation processing on the current sensing signal based on the temperature compensation coefficient.

[0073] The working principle of the above technical solution is as follows: the optical fiber sensing ring is a core component of current sensing. It uses certain physical properties of optical fiber (such as Faraday effect) to sense current. When current flows through a conductor, a magnetic field is generated around it, which affects the optical signal in the optical fiber, thereby changing certain properties of the optical signal (such as polarization state). By measuring these changes, the size of the current can be indirectly measured. The current acquisition module is responsible for sending optical signals to the optical fiber sensing ring and receiving optical signals generated by the optical fiber sensing ring under the action of the current to be measured. These signals are converted into current sensing signals through photoelectric conversion and signal processing. This process converts the optical signal in the optical fiber into an electrical signal. The temperature detection module is used to monitor the working temperature of the optical fiber sensing ring in real time. Since certain physical properties of the optical fiber sensing ring (such as refractive index, thermal expansion coefficient, etc.) will change with temperature, affecting the accuracy of current measurement. The temperature compensation module determines the temperature compensation coefficient according to the temperature signal provided by the temperature detection module. In an embodiment, the corresponding temperature compensation coefficient is determined by querying the preset temperature signal-temperature compensation coefficient data table according to the temperature signal. The temperature compensation coefficient is used to adjust the current sensing signal to eliminate the influence of temperature changes on the accuracy of current measurement. In this way, the current transformer can provide accurate current measurement values at different temperatures.

[0074] The beneficial effects of the above technical solution are as follows: the current transformer with temperature compensation function realizes accurate detection of temperature and accurate temperature compensation by integrating the optical fiber sensing ring, the current acquisition module, the temperature detection module and the temperature compensation module, thereby realizing accurate measurement of current.

[0075] According to some embodiments of the present application, the temperature detection module comprises: a light source, a polarizer, a first splitting point, a modulator, a second splitting point, a polarimeter, a detector and a demodulator; wherein,

[0076] The light source emits an optical signal, and the polarizer converts the optical signal into two linearly polarized lights. At the first splitting point, the two linearly polarized lights are split into two linearly polarized lights perpendicular to each other. The two linearly polarized lights perpendicular to each other are subjected to initial phase modulation by the modulator and are transmitted along the fast axis and slow axis of the polarization maintaining optical fiber;

[0077] After passing through the second splitting point, the linearly polarized lights on the fast axis and the slow axis are again split into two linearly polarized lights perpendicular to each other. The polarimeter only allows the two linearly polarized lights on one axis to pass through, and the light on the other axis is filtered. The feedback phase adjustment of the modulator makes the two linearly polarized lights have a specific phase difference and interfere when returning to the polarimeter. The detector converts the interference optical signal into an electrical signal. The demodulator demodulates the temperature signal from the electrical signal to determine the temperature signal of the optical fiber sensing ring.

[0078] The working principle of the above technical solution is as follows: the light source is a laser or an LED with high stability and low noise. The polarizer converts the non-polarized light signal emitted by the light source into two linearly polarized lights. At the first decomposition point, the two linearly polarized lights are decomposed into two linearly polarized lights perpendicular to each other, which are subjected to initial phase modulation by the modulator and transmitted along the fast axis and the slow axis of the polarization maintaining optical fiber. The modulator is an electro-optic or magneto-optic modulator that can change the phase of light according to external signals (such as voltage or magnetic field). The polarizer only allows two linearly polarized lights on one axis to pass through, and the light on the other axis is filtered out. In this way, only two linearly polarized lights are left on each polarization maintaining optical fiber. The two lights interfere at the polarizer to form an interference light signal. The detector converts the interference light signal into an electrical signal. This electrical signal contains temperature information because temperature affects the physical properties of the optical fiber (such as refractive index, length, etc.), thereby changing the phase difference of the interference light signal. The demodulator demodulates the temperature signal from the electrical signal output by the detector. Let P1 and P2 be the linearly polarized light power on the fast axis and the slow axis, respectively. Δ The interference light intensity I after the polarizer is represented as:

[0079]

[0080] By measuring the interference light intensity and combining the feedback phase of the modulator, Δ can be demodulated, and the temperature signal can be obtained. The high-voltage side primary current is adjusted according to the temperature signal and the temperature compensation curve.

[0081] The beneficial effects of the above technical solution are as follows: the temperature detection module utilizes the interference principle of light to measure the phase difference change caused by temperature, thereby realizing accurate measurement of temperature.

[0082] According to some embodiments of the present application, the temperature compensation module includes a ceramic heating sheet, the ceramic heating sheet is powered, and the ceramic heating sheet gradually heats and heats the optical fiber sensing ring.

[0083] The working principle of the above technical solution is as follows: the ceramic heating sheet is a high-efficiency and stable heating element, which is usually composed of a ceramic substrate and a heating resistor embedded therein. When the ceramic heating sheet is powered, the heating resistor generates heat to heat the ceramic heating sheet.

[0084] The beneficial effects of the above technical solution are: the temperature compensation module compensates for the temperature change of the optical fiber sensing ring by actively heating the ceramic heating sheet. When the temperature of the optical fiber sensing ring decreases, the ceramic heating sheet heats the optical fiber sensing ring to increase its temperature; on the contrary, when the temperature of the optical fiber sensing ring increases, its temperature can be reduced by reducing the power supply or stopping heating. In this way, the optical fiber sensing ring can maintain a relatively stable temperature during the measurement process, thereby improving the accuracy of current measurement.

[0085] According to some embodiments of the application, the temperature compensation module includes two heating solenoids with opposite winding directions, which are used to generate two magnetic fields with the same size and opposite directions. The heating solenoids are placed equidistantly on both sides of the temperature detection module.

[0086] The working principle of the above technical solution is: the heating solenoid is a kind of high-efficiency heating element, whose working principle is based on electromagnetic induction and the heat effect of current. When the current passes through the solenoid, a magnetic field is generated around it, and the current passing through the resistance generates heat, which makes the solenoid heat up. In this module, the winding directions of the two heating solenoids are opposite, so the directions of the magnetic fields they generate are also opposite. The two heating solenoids are placed equidistantly on both sides of the temperature detection module, so that their influence on the temperature detection module is uniform. This layout helps to reduce the influence of temperature gradient on temperature detection and improve the accuracy of temperature measurement.

[0087] The beneficial effects of the above technical solution are: when the ambient temperature rises, the heat generated by the heating solenoid can offset part of the influence of the ambient temperature; when the ambient temperature decreases, the heat generated by the heating solenoid can be reduced by reducing the power supply or stopping heating, so as to keep the temperature of the environment around the temperature detection module relatively stable. In this way, the influence of temperature change on the accuracy of temperature detection can be reduced. By using two heating solenoids with opposite winding directions and placing them equidistantly on both sides of the temperature detection module, the temperature compensation of the environment around the temperature detection module is realized.

[0088] According to some embodiments of the application, the state detection module is further used to:

[0089] detect a first angular velocity and a first acceleration of the temperature detection module;

[0090] determine a first angular velocity matrix according to the first angular velocity and a first acceleration matrix according to the first acceleration;

[0091] when the temperature detection module is in a stationary state, detect a second angular velocity and a second acceleration of the temperature detection module;

[0092] determine a second angular velocity matrix according to the second angular velocity and a second acceleration matrix according to the second acceleration;

[0093] Subtracting the first angular velocity matrix from the second angular velocity matrix obtains a third angular velocity matrix, determining a maximum value in the third angular velocity matrix, judging whether the maximum value is less than 0, and obtaining a first comparison result;

[0094] Subtracting the first acceleration matrix from the second acceleration matrix obtains a third acceleration matrix, determining a maximum value in the third acceleration matrix, judging whether the maximum value is less than 0, and obtaining a second comparison result;

[0095] When the first comparison result is that the maximum value in the third angular velocity matrix is less than 0 and the second comparison result is that the maximum value in the third acceleration matrix is less than 0, it indicates that the temperature detection module is in a stationary state; otherwise, the temperature detection module is in a motion state;

[0096] When it is determined that the temperature detection module is in the motion state, a first variance corresponding to the third angular velocity matrix and a second variance corresponding to the third acceleration matrix are calculated, a motion compensation coefficient table is queried according to the first variance and the second variance, a motion compensation coefficient is obtained, and the obtained temperature signal is corrected according to the motion compensation coefficient to obtain a corrected temperature signal.

[0097] The working principle of the technical scheme is as follows: the state detection module detects the first angular velocity and the first acceleration of the temperature detection module as actual detection data, and determines a first angular velocity matrix according to the first angular velocity and a first acceleration matrix according to the first acceleration. When the temperature detection module is in a stationary state, the second angular velocity and the second acceleration of the temperature detection module are detected; a second angular velocity matrix is determined according to the second angular velocity, and a second acceleration matrix is determined according to the second acceleration; the theoretical data when the temperature detection module is in the stationary state is accurately determined. The first angular velocity matrix and the second angular velocity matrix are subtracted to obtain a third angular velocity matrix, the maximum value in the third angular velocity matrix is determined, and whether it is less than 0 is judged to obtain a first comparison result; the first acceleration matrix and the second acceleration matrix are subtracted to obtain a third acceleration matrix, the maximum value in the third acceleration matrix is determined, and whether it is less than 0 is judged to obtain a second comparison result; when it is determined that the first comparison result is that the maximum value in the third angular velocity matrix is less than 0 and the second comparison result is that the maximum value in the third acceleration matrix is less than 0, it indicates that the temperature detection module is in the stationary state; otherwise, the temperature detection module is in a motion state; when the temperature detection module is in the stationary state, motion compensation is not needed, and the measured temperature signal is relatively accurate. When the temperature detection module is in the motion state, the measured temperature signal will be inaccurate, and motion compensation needs to be performed on the obtained temperature signal. When it is determined that the temperature detection module is in the motion state, a first variance corresponding to the third angular velocity matrix and a second variance corresponding to the third acceleration matrix are calculated, the first variance and the second variance reflect the fluctuation degree of the angular velocity and the acceleration of the temperature detection module in the motion state, a preset motion compensation coefficient table is queried according to the first variance and the second variance to obtain a motion compensation coefficient, wherein the preset motion compensation coefficient table is calculated based on experimental data and is used to determine the corresponding motion compensation coefficient according to the fluctuation degree of the angular velocity and the acceleration. The obtained temperature signal is corrected according to the motion compensation coefficient to obtain a corrected temperature signal, so as to eliminate or reduce the influence of motion on temperature measurement.

[0098] The beneficial effects of the technical scheme are as follows: the state detection module detects and analyzes the angular velocity and the acceleration of the temperature detection module to judge the motion state, and corrects the temperature signal according to the corresponding motion compensation coefficient calculated according to the motion state, which helps to improve the accuracy and stability of temperature measurement, especially in the case that the temperature detection module is affected by motion.

[0099] According to some embodiments of the application, the state detection module determines a first angular velocity matrix according to the first angular velocity and a first acceleration matrix according to the first acceleration, comprising:

[0100] The first angular velocity vector ω is constructed as follows: , , );in, , , These are the angular velocity components in the x, y, and z directions, respectively;

[0101] The first angular velocity matrix is ​​represented as:

[0102]

[0103] in, This is the first angular velocity matrix;

[0104] Construct the first acceleration vector a=( , , ),in, , , These are the acceleration components in the x, y, and z directions, respectively;

[0105] The first acceleration matrix is ​​represented as:

[0106]

[0107] in, This is the first acceleration matrix.

[0108] The working principle and beneficial effects of the above technical solution are as follows: The state detection module provides a precise mathematical tool for determining the motion state of the temperature detection module by constructing vectors of angular velocity and acceleration and their corresponding matrices. This method not only improves the accuracy of temperature measurement but also provides a reliable foundation for subsequent temperature signal correction processing.

[0109] According to some embodiments of the present invention, it further includes: a verification module, used to verify the temperature compensation processing result, and when it is determined that the verification fails, to regenerate the temperature compensation instruction to the temperature compensation module.

[0110] The beneficial effects of the above technical solution are as follows: The verification module provides a closed-loop control system that ensures the accuracy and reliability of temperature compensation processing. Through continuous verification and adjustment, the system can gradually approach the true temperature value, thereby improving the accuracy of temperature detection.

[0111] According to some embodiments of the present invention, the temperature compensation module includes:

[0112] The determination module is used for:

[0113] Based on several temperature signals, a preset temperature database is queried to determine the temperature compensation scheme corresponding to the several temperature signals, and the error parameters of the temperature compensation scheme are calculated.

[0114]

[0115] in, These are the error parameters for the temperature compensation scheme; This refers to the number of initial temperature compensation coefficients included in the temperature compensation scheme. The first temperature compensation scheme An initial temperature compensation coefficient;

[0116] Calculate the first reliability coefficient of the temperature compensation scheme. :

[0117]

[0118] in, It is a natural constant;

[0119] Calculate the second reliability coefficient of the temperature compensation scheme. :

[0120]

[0121] in, The first temperature compensation scheme A number;

[0122] Calculate the average of the first reliability coefficient and the second reliability coefficient. When the average value is determined to be greater than the preset threshold, the average value of several initial temperature compensation coefficients included in the temperature compensation scheme is taken as the temperature compensation coefficient.

[0123] The compensation module is used to perform temperature compensation processing on the current sensing signal based on the temperature compensation coefficient.

[0124] The working principle of the above technical solution is as follows: A preset temperature database serves as a comparison table between temperature signals and temperature compensation schemes. The determination module first receives several temperature signals as input. Then, it queries the preset temperature database to find temperature compensation schemes that match these temperature signals. The error parameter S is obtained by calculating the dispersion of each initial temperature compensation coefficient in the temperature compensation scheme. A first reliability coefficient represents the reliability of the temperature compensation scheme within the range of the error parameter S. A second reliability coefficient represents the reliability of a specific value in the temperature compensation scheme, considering its deviation from the average value. After calculating the first and second reliability coefficients, the determination module calculates their average. If the average value is greater than a preset threshold, the temperature compensation scheme is considered reliable, and the average value of several initial temperature compensation coefficients is used as the final temperature compensation coefficient for accurate determination. The compensation module receives the finally determined temperature compensation coefficient from the determination module. The compensation module uses the received temperature compensation coefficient to adjust the current sensing signal to eliminate or reduce the influence of temperature on the signal.

[0125] The beneficial effects of the above technical solution are: the temperature compensation module ensures the accuracy of the temperature signal through accurate calculation and reliable verification mechanism. The determination module is responsible for finding the best temperature compensation scheme and calculating its reliability; and the compensation module is responsible for actual temperature compensation processing of the current induction signal based on these schemes, so that the temperature compensation module can provide stable and accurate temperature compensation effect in various environments.

[0126] As shown in Figure 2 , according to some embodiments of the present application, the compensation method of the current transformer with temperature compensation function comprises steps S1-S3:

[0127] S1, based on the current acquisition module connected to the optical fiber sensing ring, generates an optical signal into the optical fiber sensing ring, and performs photoelectric conversion and signal processing on the optical signal generated by the optical fiber sensing ring under the action of the current to be measured to obtain a current induction signal;

[0128] S2, based on the temperature detection module, detecting the temperature signal of the optical fiber sensing ring;

[0129] S3, determining a temperature compensation coefficient based on the temperature signal through the temperature compensation module, and performing temperature compensation processing on the current induction signal based on the temperature compensation coefficient.

[0130] The beneficial effects of the above technical solution are: by integrating the optical fiber sensing ring, the current acquisition module, the temperature detection module and the temperature compensation module, accurate detection of temperature and accurate temperature compensation are realized, and then accurate measurement of current is realized.

[0131] According to some embodiments of the present application, the temperature compensation module determines a temperature compensation coefficient based on the temperature signal, and performs temperature compensation processing on the current induction signal based on the temperature compensation coefficient, comprising:

[0132] querying a preset temperature database based on a plurality of temperature signals, determining a temperature compensation scheme corresponding to the plurality of temperature signals, and calculating error parameters of the temperature compensation scheme;

[0133]

[0134] wherein, the error parameters of the temperature compensation scheme; the number of initial temperature compensation coefficients included in the temperature compensation scheme; the first initial temperature compensation coefficient of the temperature compensation scheme; calculating a first reliability coefficient of the temperature compensation scheme

[0135] :

[0136] ​

[0137] wherein, is a natural constant;

[0138] calculating a second reliability coefficient of the temperature compensation scheme :

[0139]

[0140] wherein, is a first numerical value of the temperature compensation scheme;

[0141] calculating a mean value of the first reliability coefficient and the second reliability coefficient, and including an average value of a plurality of initial temperature compensation coefficients in the temperature compensation scheme as a temperature compensation coefficient when determining that the mean value is greater than a preset threshold value;

[0142] performing temperature compensation processing on the current induced signal based on the temperature compensation coefficient.

[0143] The technical scheme has the beneficial effects that: the temperature compensation module ensures the accuracy of the temperature signal through accurate calculation and reliable verification mechanism. The determination module is responsible for finding the best temperature compensation scheme and calculating its reliability; and the compensation module is responsible for performing actual temperature compensation processing on the current induced signal based on the scheme, so that the temperature compensation module can provide stable and accurate temperature compensation effect in various environments.

[0144] Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application belong to the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.​

Claims

1. A current transformer having a temperature compensation function, characterized by comprising: The application relates to a current sensor, which comprises the following components: an optical fiber sensing ring, a current acquisition module, a temperature detection module and a temperature compensation module, wherein the current acquisition module is connected to the optical fiber sensing ring, generates an optical signal into the optical fiber sensing ring, and carries out photoelectric conversion and signal processing on an optical signal generated by the optical fiber sensing ring under the action of a current to be measured, so as to obtain a current sensing signal; the temperature detection module is used for detecting a temperature signal of the optical fiber sensing ring; the temperature compensation module is used for determining a temperature compensation coefficient based on the temperature signal and carrying out temperature compensation processing on the current sensing signal based on the temperature compensation coefficient; the application further comprises a state detection module, which is used for: detecting a first angular velocity and a first acceleration of the temperature detection module; determining a first angular velocity matrix according to the first angular velocity and a first acceleration matrix according to the first acceleration; detecting a second angular velocity and a second acceleration of the temperature detection module when the temperature detection module is in a static state; determining a second angular velocity matrix according to the second angular velocity and a second acceleration matrix according to the second acceleration; subtracting the first angular velocity matrix from the second angular velocity matrix to obtain a third angular velocity matrix, determining a maximum value in the third angular velocity matrix, judging whether the maximum value is less than 0, and obtaining a first comparison result; subtracting the first acceleration matrix from the second acceleration matrix to obtain a third acceleration matrix, determining a maximum value in the third acceleration matrix, judging whether the maximum value is less than 0, and obtaining a second comparison result; when it is determined that the first comparison result is that the maximum value in the third angular velocity matrix is less than 0 and the second comparison result is that the maximum value in the third acceleration matrix is less than 0, it is indicated that the temperature detection module is in a static state; otherwise, the temperature detection module is in a motion state; when it is determined that the temperature detection module is in a motion state, a first variance corresponding to the third angular velocity matrix and a second variance corresponding to the third acceleration matrix are calculated, a motion compensation coefficient table is queried according to the first variance and the second variance, the motion compensation coefficient is obtained, the obtained temperature signal is corrected according to the motion compensation coefficient, and a corrected temperature signal is obtained; the state detection module determines a first angular velocity matrix according to the first angular velocity and a first acceleration matrix according to the first acceleration, and the first angular velocity matrix is represented as: Construct a first angular velocity vector ω = (ω x , ω y , ω z ); wherein ω x , ω y , ω z are angular velocity components in x, y, z directions respectively; the first acceleration matrix is represented as: where [ω] × is the first angular velocity matrix; The first acceleration vector a = (a x ,a y ,a z ) is constructed, wherein a x ,a y ,a x are acceleration components in x, y, z directions respectively; the application further comprises a verification module, which is used for verifying a temperature compensation processing result, and re-generating a temperature compensation instruction to the temperature compensation module when it is determined that the verification fails; wherein [a] × is the first acceleration matrix; the temperature compensation module comprises: a determination module, which is used for: querying a preset temperature database based on a plurality of temperature signals, determining a temperature compensation scheme corresponding to the plurality of temperature signals, and calculating an error parameter of the temperature compensation scheme; calculating a first reliability coefficient P1 of the temperature compensation scheme: where S is an error parameter of the temperature compensation scheme; K is the number of initial temperature compensation coefficients included in the temperature compensation scheme; X i is the i-th initial temperature compensation coefficient of the temperature compensation scheme. wherein e is a natural constant; calculating a second reliability coefficient P2 of the temperature compensation scheme: calculating a mean value of the first reliability coefficient and the second reliability coefficient, and taking an average value of a plurality of initial temperature compensation coefficients included in the temperature compensation scheme as the temperature compensation coefficient when it is determined that the mean value is greater than a preset threshold value; wherein X j is the jth value of the temperature compensation scheme; a compensation module, which is used for carrying out temperature compensation processing on the current sensing signal based on the temperature compensation coefficient. ​ 2. The current transformer with temperature compensation function as claimed in claim 1, wherein, The temperature detection module comprises a light source, a polarizer, a first splitting point, a modulator, a second splitting point, a polarizing detector, a detector and a demodulator. The light source emits a light signal, the polarizer converts the light signal into two linearly polarized lights, at the first splitting point, the two linearly polarized lights are split into two linearly polarized lights perpendicular to each other, the two linearly polarized lights perpendicular to each other are subjected to initial phase modulation by the modulator, and are transmitted along the fast axis and the slow axis of the polarization maintaining optical fiber. The linearly polarized lights on the fast axis and the slow axis are split into two linearly polarized lights perpendicular to each other again through the second splitting point; the polarizing detector only allows the two linearly polarized lights on one axis to pass through, and the light on the other axis is filtered; the feedback phase adjustment of the modulator makes the two linearly polarized lights have a specific phase difference when returning to the polarizing detector and interfere; the detector converts the interference light signal into an electric signal; the demodulator demodulates the temperature signal from the electric signal to determine the temperature signal of the optical fiber sensing ring.

3. The current transformer with temperature compensation function as claimed in claim 1, wherein, The temperature compensation module comprises a ceramic heating sheet, the ceramic heating sheet is powered, and the ceramic heating sheet gradually heats and heats the optical fiber sensing ring.

4. The current transformer with temperature compensation function as claimed in claim 1, wherein, The temperature compensation module comprises two heating solenoids with opposite winding directions, which are used to generate two magnetic fields with the same size and opposite directions, and the heating solenoids are placed equidistantly on both sides of the temperature detection module.

5. The compensation method of a current transformer having a temperature compensation function according to any one of claims 1 to 4, characterized in that, It comprises: The current acquisition module is connected to the optical fiber sensing ring to generate an optical signal into the optical fiber sensing ring, and the optical signal generated by the optical fiber sensing ring under the action of the measured current is subjected to photoelectric conversion and signal processing to obtain a current sensing signal; The temperature detection module detects the temperature signal of the optical fiber sensing ring; The temperature compensation module determines the temperature compensation coefficient based on the temperature signal, and performs temperature compensation processing on the current sensing signal based on the temperature compensation coefficient; The temperature compensation module determines the temperature compensation coefficient based on the temperature signal, and performs temperature compensation processing on the current sensing signal, comprising: Querying a preset temperature database based on a plurality of temperature signals to determine a temperature compensation scheme corresponding to the plurality of temperature signals, and calculating an error parameter of the temperature compensation scheme; where S is an error parameter of the temperature compensation scheme; K is the number of initial temperature compensation coefficients included in the temperature compensation scheme; X i is the i-th initial temperature compensation coefficient of the temperature compensation scheme. Calculate the first reliability coefficient P1 of the temperature compensation scheme: Where e is a natural constant; Calculate the second reliability coefficient P2 of the temperature compensation scheme: wherein X j is the jth value of the temperature compensation scheme; Calculate the average of the first reliability coefficient and the second reliability coefficient, and when it is determined that the average is greater than a preset threshold, the average of the plurality of initial temperature compensation coefficients included in the temperature compensation scheme is taken as the temperature compensation coefficient; The temperature compensation module determines the temperature compensation coefficient based on the temperature signal, and performs temperature compensation processing on the current sensing signal.

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