A method for compensating birefringence of stress lines in an optical voltage sensor

Abstract

This invention relates to a method for compensating for stress line birefringence in an optical voltage sensor. The optical voltage sensor includes a laser, a polarizer, an electro-optic crystal, a quarter-wave plate, a first prism, a uniaxial crystal, a second prism, and an analyzer, all arranged sequentially on the same optical path. The method includes the following steps: using the output signal of the optical voltage sensor, which is superimposed with the electro-optic phase delay and the additional phase delay caused by stress line birefringence, to form a synchronously rotating conical interference spot; detecting the peak voltage moment of the AC voltage to be measured, obtaining the rotation angle of the conical interference spot at the peak voltage moment, calculating the additional phase delay caused by stress line birefringence based on the rotation angle of the conical interference spot at this moment and the standard rotation angle of the electro-optic phase delay at the peak voltage moment; and compensating the output signal of the optical voltage sensor using the calculated additional phase delay caused by stress line birefringence.

Description

TECHNICAL FIELD

[0001] The application relates to a stress line birefringence compensation method of an optical voltage sensor and belongs to the technical field of optical voltage sensor correction. BACKGROUND

[0002] The optical voltage sensor is one of electronic transformers, and compared with a traditional electromagnetic voltage transformer, the optical voltage sensor has the advantages of fast response speed, no transient magnetic saturation, small volume, light weight, safety and reliability, and shows a good application prospect. However, the long-term operation stability and reliability of the existing optical voltage sensor are difficult to meet the practical requirements, and the reason is that the temperature drift and vibration produce stress line birefringence in the electro-optic crystal and the transmission optical fiber, and the stress line birefringence is mixed with the electro-optic phase delay and is difficult to separate and compensate, thereby damaging the measurement accuracy of the optical voltage sensor.

[0003] Researchers have proposed a double-crystal method to solve the stress line birefringence problem of the electro-optic crystal, and the compensation principle is that the e light and o light propagating in the first crystal are exchanged in position when entering the second crystal through the modulation of the half-wave plate, so that the additional phase delay caused by the temperature change is offset and the electro-optic phase delay remains unchanged. This method requires that the optical properties of the two crystals are completely consistent, and considering the randomness of thermal stress birefringence and the dispersion and uncertainty of the temperature field, this requirement is difficult to meet. SUMMARY

[0004] In order to solve the problems existing in the prior art, the application provides a stress line birefringence compensation method of an optical voltage sensor.

[0005] The technical scheme of the application is as follows:

[0006] On the one hand, the application provides a stress line birefringence compensation method of an optical voltage sensor, the optical voltage sensor comprising a laser, a polarizer, an electro-optic crystal, a quarter-wave plate, a first prism, a uniaxial crystal, a second prism and a polarimeter arranged in sequence on the same optical path, and the method comprises the following steps:

[0007] The laser emits an optical signal, which sequentially passes through the polarizer, the electro-optic crystal, the quarter-wave plate, the first prism, the uniaxial crystal, the second prism and the polarimeter, and under the action of the measured voltage, the output signal is superimposed with the additional phase delay caused by the electro-optic phase delay and the stress line birefringence, forming a synchronous rotating converging cone interference light spot;

[0008] When the voltage peak of the measured alternating voltage is detected, the rotation angle of the converging cone interference light spot at the voltage peak is obtained, and the additional phase delay caused by the stress line birefringence is calculated according to the rotation angle of the converging cone interference light spot at this time and the standard rotation angle of the electro-optic phase delay at the voltage peak;

[0009] The additional phase delay caused by the stress birefringence is compensated for the output signal of the optical voltage sensor.

[0010] As a preferred embodiment, the specific steps for obtaining the rotation angle of the convergent conic interference spot at the voltage peak time, and calculating the additional phase delay caused by the stress birefringence according to the rotation angle of the convergent conic interference spot at the voltage peak time and the standard rotation angle of the electro-optic phase delay at the voltage peak time are as follows:

[0011] The rotation angle α of the spot extinction shadow of the convergent conic interference spot is obtained;

[0012] The relationship between the rotation angle of the electro-optic phase delay, the rotation angle of the additional phase delay caused by the stress birefringence and the rotation angle of the spot extinction shadow of the convergent conic interference spot is determined as follows:

[0013]

[0014] Wherein, is the rotation angle of the electro-optic phase delay, and γ is the rotation angle of the additional phase delay caused by the stress birefringence;

[0015] According to the Pockels effect, the measured alternating voltage U and satisfy:

[0016]

[0017] Wherein, U π is the half-wave voltage of the electro-optic crystal;

[0018] When the measured alternating voltage reaches the peak value, At this time, γ is calculated according to the formula.

[0019] As a preferred embodiment, a peak detection circuit is used to detect the voltage peak time of the measured alternating voltage.

[0020] On the other hand, the present application also provides a stress birefringence compensation system of an optical voltage sensor, wherein the optical voltage sensor comprises a laser, a polarizer, an electro-optic crystal, a quarter-wave plate, a first prism, a uniaxial crystal, a second prism and a polarimeter arranged in sequence in the same optical path, and the system comprises:

[0021] A starting module is used to emit an optical signal by the laser, and the optical signal sequentially passes through the polarizer, the electro-optic crystal, the quarter-wave plate, the first prism, the uniaxial crystal, the second prism and the polarimeter, and under the action of the measured voltage, the output signal is superimposed with the electro-optic phase delay and the additional phase delay caused by the stress birefringence, and a synchronous rotating convergent conic interference spot is formed.

[0022] The stress birefringence determination module is configured to detect a voltage peak time of the to-be-measured AC voltage, acquire a rotation angle of the convergent conic interference spot at the voltage peak time, and calculate an additional phase delay caused by the stress birefringence according to the rotation angle of the convergent conic interference spot at the voltage peak time and a standard rotation angle of the electro-optical phase delay at the voltage peak time.

[0023] The compensation module is configured to compensate an output signal of the optical voltage sensor by the additional phase delay caused by the stress birefringence.

[0024] As a preferred embodiment, the stress birefringence determination module specifically comprises:

[0025] The spot rotation angle acquisition unit is configured to acquire a rotation angle α of a spot extinction shadow of the convergent conic interference spot.

[0026] The linear relationship determination unit is configured to determine that a relationship between the rotation angle of the electro-optical phase delay, the rotation angle of the additional phase delay caused by the stress birefringence, and the rotation angle of the spot extinction shadow of the convergent conic interference spot is:

[0027]

[0028] wherein, is the rotation angle of the electro-optical phase delay, and γ is the rotation angle of the additional phase delay caused by the stress birefringence.

[0029] The stress birefringence calculation unit is configured to calculate the stress birefringence according to the Pockels effect, the to-be-measured AC voltage U, and satisfies:

[0030]

[0031] wherein, U π is a half-wave voltage of the electro-optical crystal.

[0032] When the to-be-measured AC voltage reaches the peak value, At this time, γ is calculated according to the formula.

[0033] As a preferred embodiment, a peak detection circuit is adopted to detect the voltage peak time of the to-be-measured AC voltage.

[0034] In another aspect, the present application further provides an electronic device, which comprises a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and the processor implements the stress birefringence compensation method of the optical voltage sensor according to any one of the embodiments of the present application when executing the program.

[0035] In still another aspect, the present application further provides a computer readable storage medium, having stored thereon a computer program, which, when executed by a processor, implements the stress birefringence compensation method of the optical voltage sensor as described in any of the embodiments of the present application.

[0036] The present application has the following advantages:

[0037] The stress birefringence compensation method of the optical voltage sensor according to the present application is based on the Pockels effect. When the AC voltage to be measured reaches the peak value, the electro-optic phase delay is a fixed value. At this time, the difference between the output signal of the optical voltage sensor and the electro-optic phase delay is the stress birefringence. The peak value of the AC voltage to be measured is determined, and the stress birefringence is detected at this time, thereby realizing the compensation of the stress birefringence. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The method flowchart of the first embodiment of the present application;

[0039] Figure 2 The principle diagram of the stress birefringence compensation of the embodiment of the present application;

[0040] Figure 3 The calculation coordinate example diagram of the light intensity distribution of the optical voltage sensor in the embodiment of the present application;

[0041] Figure 4 The simulation image example diagram of different light spots in the embodiment of the present application;

[0042] Figure 5 The principle diagram of the peak detection circuit in the embodiment of the present application.

[0043] The reference signs in the drawings are as follows:

[0044] 1, laser; 2, polarizer; 3, electro-optic crystal; 4, quarter-wave plate; 5, first prism; 6, uniaxial crystal; 7, second prism; 8, analyzer; 9, converging conic interference spot; 10, peak detection circuit; 11, standard interference spot; 12, error interference spot. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0046] It should be understood that the step numbers used herein are only for the convenience of description, and are not limited to the execution sequence of the steps.

[0047] It is to be understood that the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting thereof. As used in the description of the application and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0048] The terms "including" and "comprising" as used herein specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0049] The term "and / or" means any combination of one or more of the associated listed items and all possible combinations thereof, and includes these combinations.

[0050] Embodiment One:

[0051] Referring to Figure 1 and Figure 2 , the present embodiment proposes a stress line birefringence compensation method for an optical voltage sensor based on convergent polarized light interference and peak detection circuit, the optical voltage sensor comprising a laser 1, a polarizer 2, an electro-optic crystal 3, a quarter-wave plate 4, a first prism 5, a uniaxial crystal 6, a second prism 7 and a polarizer 8 arranged in sequence in the same optical path, the stress line birefringence compensation method comprising the following steps:

[0052] S100, a light signal is emitted by the laser 1, and linearly polarized light is obtained after passing through the polarizer 2. Under the modulation of the electric field to be measured, the linearly polarized light produces a phase delay after passing through the electro-optic crystal 3, wherein the phase delay includes an electro-optic phase delay generated by the crystal under the action of the alternating current electric field to be measured, and an additional phase delay introduced by the stress line birefringence. The light vector emitted from the electro-optic crystal 3 is combined into linearly polarized light by the elliptical polarized light after passing through the quarter-wave plate 4, and the phase delay is converted into the rotation angle of the linearly polarized light polarization plane; the outgoing light of the quarter-wave plate is converged by the first prism 5 to form a cone of light, and is incident on the uniaxial crystal 6 at different angles, and then passes through the second prism 7 and the polarizer 8, and outputs the convergent cone light interference spot 9 superimposed with the electro-optic phase delay and the additional phase delay generated by the stress line birefringence; the extinction shadow (dark lines) position of the interference spot corresponds to the polarization plane of the linearly polarized light, and rotates synchronously with the change of the phase delay.

[0053] S200, the voltage peak moment of the alternating current voltage to be measured is detected by the peak detection circuit 10, specifically, the peak detection circuit 10 used in the present embodiment is as shown in the attached Figure 5As shown. Its principle is as follows: Before the peak value of the AC voltage arrives, the amplitude of the input signal rises, controlling the sampling and protection circuit to work in sampling mode, and the output follows the input; after the peak value arrives, the input signal begins to fall, controlling the sampling and protection circuit to work in holding mode, and the output holds the peak value; the peak value is held until the valley value, and the input signal begins to rise again, and the circuit switches from holding mode to sampling mode to wait for the detection of the next peak value.

[0054] At the voltage peak, the rotation angle of the converging conical interference spot is obtained. Based on this rotation angle and the standard rotation angle of the electro-optic phase delay at the voltage peak, the additional phase delay caused by stress line birefringence is calculated. Figure 2 As shown, the image generated by the standard rotation angle at the voltage peak moment solely due to the electro-optic phase delay is the standard interference spot 11. However, after superimposing the additional phase delay generated by the birefringence of the stress line, an error interference spot 12 will be generated.

[0055] The principle of obtaining the rotation angle of the converging cone interference spot at the voltage peak moment, and calculating the additional phase delay caused by stress line birefringence based on the rotation angle of the converging cone interference spot at this time and the standard rotation angle of the electro-optic phase delay at the voltage peak moment, is as follows:

[0056] The transmission axis of polarizer 2 is parallel to the x-axis. Assuming the light intensity amplitude is 1, the electric vector E of the incident linearly polarized light... in for:

[0057]

[0058] Let the electro-optic phase delay be... Jones matrix of electro-optic crystal 3 in xy coordinate system for:

[0059]

[0060] Taking into account the stress birefringence γ introduced by temperature drift and vibration, the above equation can be rewritten as:

[0061]

[0062] The fast and slow axes of quarter-wave plate 4 are parallel to the x and y axes, respectively, and the Jones matrix W is:

[0063]

[0064] After the incident ray-polarized light passes through electro-optic crystal 3 and quarter-wave plate 4, the Jones vector is:

[0065]

[0066] The angle between the linearly polarized light emitted from quarter-wave plate 4 and the x-axis satisfy:

[0067]

[0068] therefore, It is the rotation angle of the polarization plane of linearly polarized light. Twice:

[0069]

[0070] As shown in the attached diagram Figure 3 In the coordinate system shown, P1 is the transmission axis direction of the polarizer; P2 is the transmission axis direction of the analyzer. This represents the angle from the x-axis to the e-axis, including the polarization angle. Linearly polarized light, after passing through the first prism 5 and the uniaxial crystal 6, becomes elliptically polarized light, whose Jones matrix in the oe coordinate system is:

[0071]

[0072] In the formula, δ can be expressed as:

[0073]

[0074] In the formula, l is the thickness of the uniaxial crystal 6 along the light transmission direction. In the xy coordinate system, equation (9) can be transformed into:

[0075]

[0076] The Jones vector after passing through analyzer 8 is:

[0077]

[0078] Therefore, the output light intensity I0 is:

[0079]

[0080] Taking the partial derivative of equation (12) yields the location of the maximum or minimum value of the emitted light intensity, where the minimum light intensity corresponds to the extinction shadow:

[0081]

[0082] Let equation (13) be zero, and since sin 2 Since δ / 2 is not zero, we have:

[0083] θ0=2θ1 (14)

[0084] In the formula, θ1 is the rotation angle α of the extinction shadow of the light spot, then:

[0085] θ0=2α (15)

[0086] Combining formula (7) and (15), we have And α satisfies a linear relationship:

[0087]

[0088] The output spot of the optical voltage sensor is simulated by Matlab, as shown in Fig. 2. It can be seen that the spot image rotates synchronously with the change of Figure 4 Therefore, the linear measurement of can be realized by locating the rotation angle α of the spot. According to Pockels effect, the measured voltage U and satisfy:

[0089]

[0090] where U π is the half-wave voltage of the crystal. Therefore, when the measured voltage reaches the peak value, γ is calculated according to the formula.

[0091] S300, compensate the output signal of the optical voltage sensor by the additional phase delay generated by the calculated stress birefringence.

[0092] In this embodiment, the laser 1 is a distributed feedback semiconductor light source (CLD1015) with a center wavelength of 980 nm, a spot diameter of 4 mm, and an output power of 30 mW; the electro-optic crystal 3 is BGO with a size of Φ10×50 mm 3 , and a half-wave voltage of 55.52 kV; the uniaxial crystal 6 is lithium niobate (LiNbO3, LN) with a crystal face perpendicular to the optical axis and a thickness of 10 mm along the light path; a position sensitive detector is used to detect the rotation angle of the spot, and the light sensitive surface of the detector is 9 mm×9 mm, and the working wavelength range is 400-1000 nm;

[0093] To verify the effectiveness of the method proposed in this embodiment, specific tests are also conducted. The test uses a high-low temperature alternating damp heat test chamber to provide different temperature environments, with a temperature range of -40℃ to 85℃ and a temperature fluctuation of ±0.5℃. In the example, the optical path of the optical voltage sensor is placed in the inner tank of the temperature chamber, and the temperature cycle experiment is conducted in the range of -40℃ to 85℃. The peak value detection circuit is used to determine the peak value of the measured voltage in each cycle, so as to calculate the stress birefringence and compensate it. Finally, the basic accuracy of the optical voltage sensor is recorded by the calibration instrument, as shown in Table 1. Under the temperature cycle condition, the optical voltage sensor can meet the requirement of 0.5 level accuracy.

[0094] Table 1 Basic accuracy test data

[0095] ​​

[0096] Based on the above embodiment, the method provided by the embodiment can extract and compensate the stress birefringence at the peak moment of the alternating voltage based on the linear measurement mode. The optical voltage sensor can linearly demodulate the electro-optical phase delay. When the stress birefringence exists, the output result is the linear superposition of the electro-optical phase delay and the stress birefringence. According to the Pockels effect, when the to-be-measured alternating voltage reaches the peak, the electro-optical phase delay is a fixed value (90°), at this time, the difference between the output signal of the optical voltage sensor and the electro-optical phase delay is the stress birefringence. The peak detection circuit is used to determine the peak moment of the to-be-measured alternating voltage, so that the stress birefringence can be detected and eliminated.

[0097] Embodiment two:

[0098] The embodiment provides a stress birefringence compensation system of an optical voltage sensor, the optical voltage sensor comprising a laser, a polarizer, an electro-optical crystal, a quarter-wave plate, a first prism, a uniaxial crystal, a second prism and a polarimeter arranged in sequence in the same optical path, and the system comprises:

[0099] A starting module is configured to emit an optical signal by using the laser, and the optical signal sequentially passes through the polarizer, the electro-optical crystal, the quarter-wave plate, the first prism, the uniaxial crystal, the second prism and the polarimeter. Under the action of the to-be-measured voltage, the output signal is superimposed with an additional phase delay caused by the electro-optical phase delay and the stress birefringence, and a synchronous rotating converging conical light interference spot is formed. The starting module is configured to realize the function of step S100 in the embodiment one, and details are not described herein again.

[0100] A stress birefringence determination module is configured to detect the voltage peak moment of the to-be-measured alternating voltage, obtain the rotation angle of the converging conical light interference spot at the voltage peak moment, and calculate the additional phase delay caused by the stress birefringence according to the rotation angle of the converging conical light interference spot at the voltage peak moment and the standard rotation angle of the electro-optical phase delay at the voltage peak moment. The stress birefringence determination module is configured to realize the function of step S200 in the embodiment one, and details are not described herein again.

[0101] A compensation module is configured to compensate the output signal of the optical voltage sensor by using the calculated additional phase delay caused by the stress birefringence. The compensation module is configured to realize the function of step S300 in the embodiment one, and details are not described herein again.

[0102] As a preferred embodiment of the embodiment, the stress birefringence determination module specifically comprises:

[0103] A spot rotation angle obtaining unit is configured to obtain the rotation angle α of the spot extinction shadow of the converging conical light interference spot.

[0104] The linear relationship determining unit is configured to determine that a relationship between a rotation angle of the electro-optical phase delay and an additional phase delay caused by the stress-induced birefringence and a rotation angle of a spot extinction shadow of the converging optical spot interference spot is:

[0105]

[0106] wherein, is the rotation angle of the electro-optical phase delay, and γ is the rotation angle of the additional phase delay caused by the stress-induced birefringence;

[0107] The stress-induced birefringence calculating unit is configured to calculate the stress-induced birefringence according to the Pockels effect, the to-be-measured alternating voltage U and satisfies:

[0108]

[0109] wherein, U π is the half-wave voltage of the electro-optical crystal;

[0110] When the to-be-measured alternating voltage reaches the peak value, the peak value detection circuit detects the voltage peak value time point of the to-be-measured alternating voltage. At this time, γ is calculated according to the formula.

[0111] As a preferred embodiment of the present embodiment, the peak value detection circuit is used to detect the voltage peak value time point of the to-be-measured alternating voltage.

[0112] Embodiment three:

[0113] The present embodiment provides an electronic device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of the embodiments of the present application when executing the program.

[0114] Embodiment four:

[0115] The present embodiment provides a computer readable storage medium, which stores a computer program, wherein the program is executed by a processor to implement the method according to any one of the embodiments of the present application.

[0116] In the embodiments of the present application, "at least one" means one or more, and "multiple" means two or more. The "and / or" describes the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which means that A exists alone, A and B exist together, and B exists alone. Wherein A and B can be singular or plural. The character " / " generally represents that the front and rear associated objects are in an "or" relationship. "At least one of the following" and the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b and c can mean: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b and c can be single or multiple.

[0117] Those skilled in the art can understand that the units and algorithm steps described in the embodiments disclosed herein can be realized in electronic hardware, computer software and combination of the electronic hardware and the computer software. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to realize the described functions for each specific application, but the realization should not be considered beyond the scope of the present application.

[0118] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working processes of the above-described system, device and unit can refer to the corresponding processes in the foregoing method embodiments, which will not be described here.

[0119] In several embodiments provided in the present application, any function realized in the form of a software function unit and sold or used as an independent product can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the parts of the technical solutions that make contributions to the prior art or the parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0120] The above only describes the embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation based on the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A stress line birefringence compensation method for an optical voltage sensor, characterized by, The optical voltage sensor comprises a laser, a polarizer, an electro-optic crystal, a quarter-wave plate, a first prism, a uniaxial crystal, a second prism and a polarimeter arranged in sequence in the same optical path, and the method comprises the following steps: The laser emits an optical signal which passes through the polarizer, the electro-optic crystal, the quarter-wave plate, the first prism, the uniaxial crystal, the second prism and the polarimeter in sequence, and under the action of the voltage to be measured, the output signal is superimposed with an additional phase delay caused by the electro-optic phase delay and the stress birefringence, and a synchronous rotating converging conic interference light spot is formed; The voltage peak time of the measured alternating voltage is detected, the rotating angle of the converging conic interference light spot at the voltage peak time is obtained, and the additional phase delay caused by the stress birefringence is calculated according to the rotating angle of the converging conic interference light spot at this time and the standard rotating angle of the electro-optic phase delay at the voltage peak time; The output signal of the optical voltage sensor is compensated by the calculated additional phase delay caused by the stress birefringence.

2. The stress line birefringence compensation method of an optical voltage sensor according to claim 1, wherein, The specific steps of obtaining the rotating angle of the converging conic interference light spot at the voltage peak time and calculating the additional phase delay caused by the stress birefringence according to the rotating angle of the converging conic interference light spot at this time and the standard rotating angle of the electro-optic phase delay at the voltage peak time are as follows: The rotating angle α of the light spot extinction shadow of the converging conic interference light spot is obtained; The relationship between the rotating angles of the electro-optic phase delay and the additional phase delay caused by the stress birefringence and the rotating angle of the light spot extinction shadow of the converging conic interference light spot is determined as follows: wherein is the rotation angle of the electro-optic phase delay, and γ is the rotation angle of the additional phase delay due to stress-induced birefringence. According to the Pockels effect, the measured alternating voltage U is related to the applied voltage U0 by satisfying: wherein U π is the half-wave voltage of the electro-optic crystal; When the AC voltage to be measured reaches the peak value, At this time, γ is calculated according to the formula.

3. The stress birefringence compensation method of the optical voltage sensor according to claim 1, characterized in that: A peak detection circuit is used to detect the voltage peak time of the measured alternating voltage.

4. A stress line birefringence compensation system for an optical voltage sensor, characterized by, The optical voltage sensor comprises a laser, a polarizer, an electro-optic crystal, a quarter-wave plate, a first prism, a uniaxial crystal, a second prism and a polarimeter arranged in sequence in the same optical path, and the system comprises: The starting module is used to emit an optical signal by the laser, and the optical signal passes through the polarizer, the electro-optic crystal, the quarter-wave plate, the first prism, the uniaxial crystal, the second prism and the polarimeter in sequence, and under the action of the voltage to be measured, the output signal is superimposed with an additional phase delay caused by the electro-optic phase delay and the stress birefringence, and a synchronous rotating converging conic interference light spot is formed; The stress birefringence determination module is used to detect the voltage peak time of the measured alternating voltage, obtain the rotating angle of the converging conic interference light spot at the voltage peak time, and calculate the additional phase delay caused by the stress birefringence according to the rotating angle of the converging conic interference light spot at this time and the standard rotating angle of the electro-optic phase delay at the voltage peak time; The compensation module is used to compensate the output signal of the optical voltage sensor by the calculated additional phase delay caused by the stress birefringence.

5. A stress line birefringence compensation system for an optical voltage sensor according to claim 4, wherein, The stress birefringence determination module specifically comprises: The light spot rotating angle acquisition unit is used to obtain the rotating angle α of the light spot extinction shadow of the converging conic interference light spot; The linear relationship determination unit is used to determine the relationship between the rotating angles of the electro-optic phase delay and the additional phase delay caused by the stress birefringence and the rotating angle of the light spot extinction shadow of the converging conic interference light spot as follows: wherein is the rotation angle of the electro-optic phase delay, and γ is the rotation angle of the additional phase delay due to stress-induced birefringence. The stress line birefringence calculation unit is configured to satisfy the following equation according to the Pockels effect: wherein U π is the half-wave voltage of the electro-optic crystal; When the AC voltage to be measured reaches the peak value, At this time, γ is calculated according to the formula.

6. The stress line birefringence compensation system of an optical voltage sensor according to claim 4, characterized in that: The peak detection circuit is configured to detect a voltage peak time of the to-be-measured alternating voltage.

7. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor implements the stress line birefringence compensation method of the optical voltage sensor according to any one of claims 1 to 3 when executing the program.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the stress line birefringence compensation method of the optical voltage sensor according to any one of claims 1 to 3.

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