An all-fiber current transformer vibration fault quantification calculation method and system

Abstract

The application discloses a kind of full optical fiber current transformer vibration fault quantification calculation method and system, belong to full optical fiber current transformer technical field.The method of the present application includes: for the polarization-maintaining light path of full optical fiber current transformer, establish the microelement analysis model of polarization-maintaining optical fiber of full optical fiber current transformer under vibration stress;Based on the microelement analysis model, select optical fiber microelement on optical fiber transmission path, determine the non-reciprocal phase difference model introduced by the optical path change of optical fiber microelement;According to the non-reciprocal phase difference model, based on photoelastic effect and stress-strain effect, the non-reciprocal phase difference under the action of vibration stress field is calculated, and the vibration fault of full optical fiber current transformer is quantified by the non-reciprocal phase difference.The present application can evaluate the influence parameter and influence degree of vibration on full optical fiber current transformer current measurement, and then take corresponding measures to suppress the influence of vibration, provide a kind of design high anti-vibration full optical fiber current transformer solution.

Description

Technical Field

[0001] This invention relates to the field of all-fiber current transformer technology, and more specifically, to a method and system for quantitative calculation of vibration faults in all-fiber current transformers. Background Technology

[0002] The all-fiber current transformer is primarily based on the Faraday magneto-optical effect in its physical mechanism. It employs interferometry to measure current by detecting the phase difference between two circularly polarized beams. Depending on the signal detection principle, all-fiber current transformers are divided into open-loop and closed-loop schemes. The open-loop scheme typically uses piezoelectric ceramics as the phase modulator. The main problem is that measurement accuracy is affected by optical power and circuit gain drift, and the measurement results exhibit a trigonometric linear approximation (sinx=x), with nonlinearity at high currents. The closed-loop scheme uses integrated optical devices for phase modulation. The closed-loop structure effectively reduces the influence of optical power, circuit gain, and other loop forward gain factors, significantly reducing the requirements for optical devices. The feedback phase shift tracks the Faraday phase shift generated by the measured current in real time, resulting in high system linearity.

[0003] In both schemes, the interference light intensity signal has the same expression form, namely: (1) Where, Δ m ( t () represents the modulation phase. F ( t ) represents the phase difference between the two signal beams.

[0004] When the all-fiber current transformer is unaffected by vibration, the phase difference only includes the Faraday phase shift proportional to the measured current, that is: F = 4VNI (2) However, when the all-fiber current transformer is subjected to a vibration environment, a non-reciprocal effect will occur in the optical path under the action of a time-varying vibration stress field: F = 4VNI+ d (t) (3) Phase difference caused by this non-reciprocal effect d(t) will be indistinguishable from the Faraday phase shift, and the current obtained by phase demodulation will undergo huge changes, causing a sudden change in the measurement results of the all-fiber current transformer. The degree of change may be much greater than the actual measured current, triggering the relay protection device to operate, which in turn causes power system measurement faults, and in severe cases, may even cause DC system blockage.

[0005] The phenomenon where a medium undergoes elastic deformation under external stress, resulting in a change in refractive index, is called the elasto-optic effect. The optical system of a fiber optic current transformer is an orthogonal polarization interferometer. The elasto-optic effect is the physical basis for maintaining the polarization state of light waves in the polarization-maintaining fiber, and it is also the root cause of the influence of vibration on the performance of the fiber optic current transformer. Based on the analysis of the crystal elasto-optic effect, the change in refractive index of the fiber under external stress can be calculated. Any external stress acting on the fiber can be considered as a combination of radial and axial stresses. Figure 1 As shown, the stress on the optical fiber is decomposed into radial stress. P 1. P 2 and longitudinal stress P 3. Calculate the resulting strain: (4) The strain of the optical fiber is: (5) In the formula, m Poisson's ratio, E It is the elastic modulus.

[0006] According to equation (5), we get: (6) because ( i = 1, 2, 3), then the refractive index change Δ in the three directions. n 1. Δ n 2 and Δ n 3 are respectively: (7) Since light waves propagate longitudinally along the optical fiber, birefringence is only related to the radial refractive index distribution. n 1. n 2 is related to, and with n 3 is irrelevant; therefore, we will only discuss Δ. n 1 and Δ n 2. The corresponding refractive index difference is: (8) Summary of the Invention

[0007] To address the above problems, this invention proposes a method for quantitative calculation of vibration faults in all-fiber current transformers, comprising: For the polarization-maintaining optical path of an all-fiber current transformer, a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress is established. Based on the aforementioned micro-element analysis model, fiber micro-elements are selected along the fiber transmission path, and the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-element is determined. Based on the non-reciprocal phase difference model, the non-reciprocal phase difference under the action of vibration stress field is calculated based on the elasto-optic effect and stress-strain effect. The non-reciprocal phase difference is used to quantify the vibration fault of the all-fiber current transformer.

[0008] Optionally, based on the elasto-optical effect and the stress-strain effect, the non-reciprocal phase difference under the action of the vibrational stress field is calculated, including: Based on the elastic-optical effect and the stress-strain effect, the changes in the refractive index and length of the optical fiber caused by time-varying stress are calculated. Based on the changes in the refractive index and length of the optical fiber caused by time-varying stress, the non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect are calculated respectively. The non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect is accumulated and integrated along the optical signal transmission path to calculate the non-reciprocal phase difference under the action of the vibration stress field.

[0009] Optionally, the non-reciprocal phase difference introduced by the photoelastic effect is calculated, and the non-reciprocal phase difference introduced by the photoelastic effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference caused by the radial stress acting on the infinitesimal element due to the elasto-optic effect is calculated using the following formula: (1) Integrating equation (1) over the length of the polarization-maintaining delay fiber, we get: (2) The non-reciprocal phase difference caused by the axial stress acting on the infinitesimal element due to the elastic-optical effect is calculated using the following formula: (3) Integrating equation (3) over the length of the polarization-maintaining delay fiber, we get: (4) in, The non-reciprocal phase difference introduced by the photoelastic effect For refractive index, For Young's modulus, For fiber radius, The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Poisson's ratio, and The elastic coefficient is 1. Angular frequency, For time, The speed of light in a vacuum. The distance from the vibration location to the optical fiber. for Integral over the length of the polarization-maintaining delay fiber The bending radius of the optical fiber. The axial stress amplitude acting on the polarization-maintaining delay fiber under vibration conditions. This represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration conditions.

[0010] Optionally, the non-reciprocal phase difference introduced by the stress-strain effect is calculated, and the non-reciprocal phase difference introduced by the stress-strain effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference between the two signal beams introduced by the stress-strain effect, accumulated through the infinitesimal element, is calculated using the following formula: (5) Integrating equation (5) over the length of the polarization-maintaining delay fiber, we get: (6) in, The non-reciprocal phase difference introduced by stress-strain effects and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Angular frequency, To the total length of the polarization-maintaining delay fiber, The distance from the vibration location to the optical fiber. The speed of light in a vacuum. is the refractive index.

[0011] Optionally, the formula for calculating the non-reciprocal phase difference under the action of the vibration stress field is as follows: (7) in, This refers to the non-reciprocal phase difference under the action of a vibrational stress field. The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. For refractive index, For Young's modulus, For fiber radius, Poisson's ratio, and The elastic coefficient is 1. λ is the wavelength of light in a vacuum. The bending radius of the optical fiber. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. To the total length of the polarization-maintaining delay fiber, The speed of light in a vacuum. Angular frequency, For time.

[0012] Furthermore, this invention also proposes a quantitative calculation system for vibration faults in all-fiber current transformers, comprising: The modeling unit is used to establish a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress for the polarization-maintaining optical path of the all-fiber current transformer. The first analysis unit is used to select fiber micro-elements on the fiber transmission path based on the micro-element analysis model, and determine the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-element. The second analysis unit is used to calculate the non-reciprocal phase difference under the action of vibration stress field based on the non-reciprocal phase difference model, the elastic-optical effect and the stress-strain effect, and to quantify the vibration fault of the all-fiber current transformer using the non-reciprocal phase difference.

[0013] Optionally, based on the elasto-optical effect and the stress-strain effect, the non-reciprocal phase difference under the action of the vibrational stress field is calculated, including: Based on the elastic-optical effect and the stress-strain effect, the changes in the refractive index and length of the optical fiber caused by time-varying stress are calculated. Based on the changes in the refractive index and length of the optical fiber caused by time-varying stress, the non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect are calculated respectively. The non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect is accumulated and integrated along the optical signal transmission path to calculate the non-reciprocal phase difference under the action of the vibration stress field.

[0014] Optionally, the non-reciprocal phase difference introduced by the photoelastic effect is calculated, and the non-reciprocal phase difference introduced by the photoelastic effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference caused by the radial stress acting on the infinitesimal element due to the elasto-optic effect is calculated using the following formula: (1) Integrating equation (1) over the length of the polarization-maintaining delay fiber, we get: (2) The non-reciprocal phase difference caused by the axial stress acting on the infinitesimal element due to the elastic-optical effect is calculated using the following formula: (3) Integrating equation (3) over the length of the polarization-maintaining delay fiber, we get: (4) in, The non-reciprocal phase difference introduced by the photoelastic effect For refractive index, For Young's modulus, For fiber radius, The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Poisson's ratio, and The elastic coefficient is 1. Angular frequency, For time, The speed of light in a vacuum. The distance from the vibration location to the optical fiber. for Integral over the length of the polarization-maintaining delay fiber The bending radius of the optical fiber. The axial stress amplitude acting on the polarization-maintaining delay fiber under vibration conditions. This represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration conditions.

[0015] Optionally, the non-reciprocal phase difference introduced by the stress-strain effect is calculated, and the non-reciprocal phase difference introduced by the stress-strain effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference between the two signal beams introduced by the stress-strain effect, accumulated through the infinitesimal element, is calculated using the following formula: (5) Integrating equation (5) over the length of the polarization-maintaining delay fiber, we get: (6) in, The non-reciprocal phase difference introduced by stress-strain effects and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Angular frequency, To the total length of the polarization-maintaining delay fiber, The distance from the vibration location to the optical fiber. The speed of light in a vacuum. is the refractive index.

[0016] Optionally, the formula for calculating the non-reciprocal phase difference under the action of the vibration stress field is as follows: (7) in, This refers to the non-reciprocal phase difference under the action of a vibrational stress field. The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. For refractive index, For Young's modulus, For fiber radius, Poisson's ratio, and The elastic coefficient is 1. λ is the wavelength of light in a vacuum. The bending radius of the optical fiber. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. To the total length of the polarization-maintaining delay fiber, The speed of light in a vacuum. Angular frequency, For time.

[0017] In another aspect, the present invention also provides a computing device, comprising: one or more processors; A processor is used to execute one or more programs; When the one or more programs are executed by the one or more processors, the method described above is implemented.

[0018] In another aspect, the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the method described above.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a method for quantifying vibration faults in all-fiber current transformers, comprising: establishing a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress for the polarization-maintaining optical path; selecting fiber micro-elements along the fiber transmission path based on the micro-element analysis model, and determining the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-elements; calculating the non-reciprocal phase difference under the action of the vibration stress field based on the elastic-optical effect and stress-strain effect according to the non-reciprocal phase difference model, and quantifying the vibration faults of the all-fiber current transformer using the non-reciprocal phase difference. This invention can assess the influence parameters and degree of vibration on the current measurement of all-fiber current transformers, and then take corresponding measures to suppress the influence of vibration, providing a solution for designing highly vibration-resistant all-fiber current transformers. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the force decomposition of an optical fiber; Figure 2 This is a flowchart of the method of the present invention; Figure 3 This is a polarization-maintaining optical path diagram of an all-fiber current transformer according to an embodiment of the method of the present invention; Figure 4 This is a diagram of a micro-element analysis model under vibration stress in an embodiment of the method of the present invention; Figure 5 This is a schematic diagram of the radial stress of the polarization-maintaining delay fiber in an embodiment of the method of the present invention. Figure 6 This is a graph showing the relationship between the refractive index difference and radial stress of an optical fiber in an embodiment of the method of the present invention. Figure 7 This is a graph showing the relationship between the refractive index difference and axial stress of an optical fiber in an embodiment of the method of the present invention. Figure 8 This is a graph showing the relationship between the non-reciprocal phase difference and radial stress in an embodiment of the method of the present invention. Figure 9 This is a graph showing the relationship between the non-reciprocal phase difference and axial strain in an embodiment of the method of the present invention. Figures 10(a) and (b) are graphs showing the relationship between phase difference and frequency in an embodiment of the method of the present invention, and waveforms of non-reciprocal phase difference at different frequencies; Figures 11(a) and (b) show the relationship between phase difference and fiber length in an embodiment of the method of the present invention, and the waveforms of non-reciprocal phase difference under different fiber lengths. Figure 12 This is a graph showing the relationship between the non-reciprocal phase difference and the optical fiber bending radius in an embodiment of the method of the present invention. Figure 13 This is a diagram showing the relationship between the non-reciprocal phase difference and the fiber beat length in an embodiment of the method of the present invention. Figure 14 This is a structural diagram of the system of the present invention. Detailed Implementation

[0021] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0022] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0023] Example 1: This invention proposes a quantitative calculation method S100 for vibration faults in all-fiber current transformers, such as... Figure 2 As shown, it includes: S101, For the polarization-maintaining optical path of the all-fiber current transformer, establish a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress. S102, Based on the micro-element analysis model, select fiber micro-elements on the fiber transmission path and determine the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-element. S103. Based on the non-reciprocal phase difference model, the non-reciprocal phase difference under the action of vibration stress field is calculated based on the elastic-optical effect and stress-strain effect. The non-reciprocal phase difference is used to quantify the vibration fault of the all-fiber current transformer.

[0024] Among them, based on the elasto-optical effect and the stress-strain effect, the non-reciprocal phase difference under the action of the vibration stress field is calculated, including: Based on the elastic-optical effect and the stress-strain effect, the changes in the refractive index and length of the optical fiber caused by time-varying stress are calculated. Based on the changes in the refractive index and length of the optical fiber caused by time-varying stress, the non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect are calculated respectively. The non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect is accumulated and integrated along the optical signal transmission path to calculate the non-reciprocal phase difference under the action of the vibration stress field.

[0025] The non-reciprocal phase difference introduced by the photoelastic effect is calculated, and the non-reciprocal phase difference introduced by the photoelastic effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference caused by the radial stress acting on the infinitesimal element due to the elasto-optic effect is calculated using the following formula: (1) Integrating equation (1) over the length of the polarization-maintaining delay fiber, we get: (2) The non-reciprocal phase difference caused by the axial stress acting on the infinitesimal element due to the elastic-optical effect is calculated using the following formula: (3) Integrating equation (3) over the length of the polarization-maintaining delay fiber, we get: (4) in, The non-reciprocal phase difference introduced by the photoelastic effect For refractive index, For Young's modulus, For fiber radius, The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Poisson's ratio, and The elastic coefficient is 1. Angular frequency, For time, The speed of light in a vacuum. The distance from the vibration location to the optical fiber. for Integral over the length of the polarization-maintaining delay fiber The bending radius of the optical fiber. The axial stress amplitude acting on the polarization-maintaining delay fiber under vibration conditions. This represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration conditions.

[0026] The non-reciprocal phase difference introduced by the stress-strain effect is calculated, and the non-reciprocal phase difference introduced by the stress-strain effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference between the two signal beams introduced by the stress-strain effect, accumulated through the infinitesimal element, is calculated using the following formula: (5) Integrating equation (5) over the length of the polarization-maintaining delay fiber, we get: (6) in, The non-reciprocal phase difference introduced by stress-strain effects and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Angular frequency, To the total length of the polarization-maintaining delay fiber, The distance from the vibration location to the optical fiber. The speed of light in a vacuum. is the refractive index.

[0027] The formula for calculating the non-reciprocal phase difference under the action of the vibration stress field is as follows: (7) in, This refers to the non-reciprocal phase difference under the action of a vibrational stress field. The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. For refractive index, For Young's modulus, For fiber radius, Poisson's ratio, and The elastic coefficient is 1. λ is the wavelength of light in a vacuum. The bending radius of the optical fiber. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. To the total length of the polarization-maintaining delay fiber, The speed of light in a vacuum. Angular frequency, For time.

[0028] The analysis process of the above method will be explained in detail below: Specifically, it includes: The polarization-maintaining optical path of an all-fiber current transformer is as follows: Figure 3 As shown.

[0029] For the aforementioned polarization-maintaining optical path, a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress is established as follows: Figure 4 Show.

[0030] According to electromagnetic wave theory, when a light wave passes through a length of... L After the optical fiber is inserted, the phase delay of the emitted light wave is: (8) Under external stress, the refractive index of the optical fiber changes due to the elastic-optical effect. According to the stress-strain effect of the elastic body, the length of the light wave propagation path also changes. These factors lead to an additional phase shift during light propagation along the optical fiber. A micro-element is selected along the optical fiber propagation path to analyze the non-reciprocal phase difference introduced by the change in the optical path length (the product of refractive index and length) of the micro-element. (9) Where, Δ n Δ is the change in refractive index of the optical fiber. L = e 3 L This is the change in fiber length. e 3 represents the axial strain of the optical fiber. e 3 can be represented as e 3 = ( p 3 - pm 1 - pm 2) / E .

[0031] Substituting equation (6) into equation (9), we can obtain the additional phase of light waves with different polarization directions, namely: (10) (11) In equations (10) and (11), the first term is the additional phase shift introduced by the stress-strain effect; the second term includes two parts: the additional phase shift introduced by the elasto-optical effect and the additional phase shift introduced by the combined effect of the elasto-optical effect and the stress-strain effect, the latter being a second-order minor quantity.

[0032] Analyze the non-reciprocal phase difference introduced by vibration disturbance when the measured current is 0, assuming the distance sensing fiber end... l There is a vibration stress disturbance at the location. P ( t) The length of the region of action is a infinitesimal d. l The phase differences accumulated during the round-trip propagation of X- and Y-polarized light are as follows: (12) (13) in, n x , n y These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. e 3 represents the axial strain of the optical fiber. t =2 nl / c The time interval between two round trips of the light wave passing through the disturbance point. cThe speed of light in a vacuum. L The total length of the polarization-maintaining delay fiber.

[0033] The phase difference between the two signal beams is: (14) Among them, the first term d A The phase difference is introduced by the change in the refractive index of the optical fiber due to vibrational stress via the elasto-optic effect; the second term d B The phase difference introduced by the axial strain of the optical fiber due to vibration stress; the third term d C The combined effect of the two is a second-order minor quantity.

[0034] Under vibration, time-varying mechanical stress is transmitted from the housing and mechanical structural components to the polarization-maintaining delay fiber. The fiber is situated within a complex dynamic system, and its stress state is related to its own looping state, curing method (whether adhesive is used), as well as the damping introduced by the skeleton structure (which may also detach from the skeleton) and mechanical fasteners. The complex stress can be regarded as a superposition of a series of fundamental and harmonic signals of different frequencies. The non-reciprocal phase difference introduced by the elasto-optic effect and stress-strain effect will be calculated below.

[0035] (1) Non-reciprocal phase difference introduced by the photoelastic effect: In fiber optic current transformers, the length of polarization-maintaining delay fiber is typically over 100m, and it is coiled in the form of a fiber loop within the secondary housing of the transformer. Under vibration stress in different directions, the stress on the polarization-maintaining delay fiber can be decomposed into radial stress and axial stress.

[0036] Radial stress: such as Figure 5 As shown, let the radial stress acting on the polarization-maintaining delay fiber be the linear stress, and the stress per unit length be... f According to the theory of elasticity, in the coordinate system shown in the figure, the stress distribution in the X and Y directions is as follows: (15) (16) in, r Let be the outer radius of the optical fiber. Then the stress distribution at the fiber core is: (17) (18) Substituting equations (17) and (18) into equation (7), the refractive index difference caused by radial stress is: (19) For quartz optical fibers, refractive index n=1.458, Young's modulus E = 7.3 × 10 10 N / m 2 Poisson's ratio m = 0.17, elastic coefficient p 11 = 0.121, p 12 = 0.270, fiber outer diameter r = 62.5μm, such as Figure 6 As shown, the refractive index difference between the two orthogonal directions of the optical fiber increases with increasing radial stress, and the refractive index difference caused by unit linear stress is 7.54 × 10⁻⁶. -8 .

[0037] Let the radial stress acting on the polarization-maintaining delay fiber under vibration be: f = f 0sin( ωt ), f 0 represents the amplitude. oh Let be the angular frequency. According to the following formula, the frequency acting on the infinitesimal element d... l The non-reciprocal phase difference caused by radial stress is: (20) From the above equation, it can be seen that the non-reciprocal phase difference introduced by radial stress under single-point vibration disturbance is related to the stress amplitude, vibration frequency, and distance between the disturbance point and the end mirror of the sensing fiber. Because ohl / c Since the vibration frequency is less than π / 2, the higher the vibration frequency, the farther the disturbance point is from the end of the sensing fiber, the greater the radial stress amplitude, and the greater the non-reciprocal phase difference.

[0038] Integrating over the length of the polarization-maintaining delay fiber, we get: (twenty one) After axially stressed optical fibers are wound into loops, the linear birefringence caused by axial tension depends not only on the magnitude of the stress but also on the bending radius of the fiber. It increases with increasing axial stress and decreases with increasing bending radius. For example... Figure 7 As shown, when the fiber bending radius R When the diameter is 40 mm, the refractive index difference caused by axial stress per MPa is 1.04 × 10⁻⁶. -8 Linear birefringence introduced by axial stress exists only under the condition of fiber bending; axial stress in a fiber under pure tension does not produce linear birefringence.

[0039] Let the axial stress acting on the polarization-maintaining delay fiber under vibration be: s z = sz0 sin( ωt ), s z0 For amplitude, oh Let be the angular frequency. According to equation (14), the angular frequency is applied to the infinitesimal element d. l The non-reciprocal phase difference caused by the axial stress is: (twenty two) From equation (22), it can be seen that the refractive index difference caused by pure bending is generated by the bending stress inside the optical fiber, which is independent of the external vibration stress field and is a constant stress, and does not generate a non-reciprocal phase difference; the non-reciprocal phase difference introduced by axial stress under single-point vibration disturbance is related to the stress amplitude, vibration frequency, and the distance between the disturbance point and the end mirror of the sensing fiber. oh nl / c Since the frequency of vibration is less than π / 2, the higher the frequency of vibration, the farther the distance between the disturbance point and the end of the sensing fiber, the greater the stress amplitude, and the greater the non-reciprocal phase difference.

[0040] Integrating equation (22) over the length of the polarization-maintaining delay fiber, we get: (twenty three) in, e 30 = / E For axial strain.

[0041] (2) Non-reciprocal phase difference introduced by stress-strain effects: The strain generated by the axial stress acting on the polarization-maintaining delay fiber under vibration is: e 3 = e 30 sin( ωt ), s 30 For amplitude, oh Let be the angular frequency. According to equation (14), the two signal beams pass through the infinitesimal element d in a round trip. l The accumulated non-reciprocal phase difference is: (twenty four) From equation (24), it can be seen that the phase difference introduced by the stress-strain effect under single-point vibration disturbance is related to the refractive index difference of the optical fiber, the axial strain amplitude, the frequency, and the distance between the disturbance point and the end mirror of the sensing optical fiber. ohl / c Since the frequency of vibration is less than π / 2, the higher the vibration frequency, the farther the disturbance point is from the end of the sensing fiber, the greater the axial strain amplitude, and the greater the non-reciprocal phase difference. A typical value for the fast-axis and slow-axis refractive index difference in polarization-maintaining fiber is 5.5 × 10⁻⁶. -4The refractive index difference caused by optical fiber bending stress and vibration time-varying stress is within 10. -7 The magnitude is negligible compared to this. In calculating the phase difference introduced by the axial stress-strain effect, only the intrinsic birefringence of the polarization-maintaining fiber needs to be considered.

[0042] Integrating equation (25) over the length of the polarization-maintaining delay fiber, we get: (25) Equations (23) and (25) are both non-reciprocal phase differences introduced by axial strain in optical fibers, but their meanings are different. Equation (25) is the phase difference introduced by the change in the length of the polarization-maintaining delay fiber caused by axial stress, while Equation (23) is the phase difference introduced by the change in the radial refractive index caused by axial stress under optical fiber bending conditions.

[0043] Based on equations (21), (23) and (25), the non-reciprocal phase difference under the action of the vibration stress field is obtained as follows: (26) Among them, the influence of radial stress: Let the radial stress acting on the polarization-maintaining delay fiber under vibration be: f = f 0 sin( ωt ),in oh =4000π rad / s. The length of the polarization-maintaining delay fiber is taken as... L = 500m, outer diameter r = 62.5μm, and the non-reciprocal phase difference is simulated and calculated according to equation (22). Figure 8 The relationship curve between the amplitude of the non-reciprocal phase difference and the amplitude of the radial stress is given. The phase difference increases with the increase of the radial stress. Under the conditions of high-frequency vibration with a vibration frequency of 2kHz and a transit time of 5μs and long delay, the 0.1N / m linear stress acting on the optical fiber can produce a phase difference of 0.55rad.

[0044] Effect of axial strain: Let the axial strain of the polarization-maintaining delay fiber under vibration be: e 3 = e 30 sin( ωt ),in oh = 4000πrad / s. The length of the polarization-maintaining delay fiber is taken as... L = 500m, outer diameter r = 62.5μm, refractive index difference n x - n y = 5.5 × 10 -4 Bending radiusR = 50mm, and the non-reciprocal phase difference is simulated and calculated according to equations (24) and (26). Figure 9 The relationship between the amplitude of the non-reciprocal phase difference and the amplitude of the fiber axial strain is presented. The phase difference increases with the increase of the axial strain. Under high-frequency vibration conditions of 2kHz, transit time of 5μs, and long delay, the fiber axial strain is 1×10⁻⁶. -5 The strain can produce a phase difference of 0.85 rad.

[0045] The effect of vibration frequency: Let the radial stress acting on the polarization-maintaining delay fiber under vibration be: f = f 0 sin(2 πf v t ), f0 = 0.1 N / m; axial strain e 3= e 30 sin(2 πf v t ), e 30 = 1×10 -5 The length of the polarization-maintaining delay fiber is taken. L = 500m, outer diameter r = 62.5μm, refractive index difference n x - n y = 5.5 × 10 -4 Bending radius R = 50mm, and the non-reciprocal phase difference is simulated and calculated according to Equation (26). Figures 10(a) and 10(b) show the relationship curves between the amplitude of the non-reciprocal phase difference and the vibration frequency. It can be seen that the phase difference and the vibration frequency are approximately linearly related. The fiber optic current transformer is more susceptible to high-frequency vibration. Under the same vibration stress field, the higher the vibration frequency, the larger the non-reciprocal phase difference. The phase difference introduced by the 2kHz high-frequency vibration is nearly 40 times that of the 50Hz vibration.

[0046] The effect of polarization-maintaining delay fiber length: Let the radial stress acting on the polarization-maintaining delay fiber under vibration be: f = f 0 sin( ωt ), f 0 = 0.1 N / m; Axial strain e 3 = e 30 sin( ωt ), e30 = 1×10 -5 angular frequency of vibration oh = 4000π rad / s. The outer diameter of the polarization-maintaining delay fiber is taken as... r = 62.5μm, refractive index difference n x - n y = 5.5 × 10 -4 Bending radius R = 50mm, and the non-reciprocal phase difference is simulated and calculated according to equation (26). Figures 11(a) and (b) show the relationship curves between the amplitude of the non-reciprocal phase difference and the length of the polarization-maintaining delay fiber. It can be seen that the phase difference and the fiber length are approximately a quadratic function relationship; the longer the length of the polarization-maintaining delay fiber, the more easily the fiber current transformer is affected by vibration; when the length of the polarization-maintaining delay fiber is 500m, the non-reciprocal phase difference is 25 times that when the length is 100m.

[0047] The effect of the bending radius of polarization-maintaining delay fiber: Let the axial strain of the polarization-maintaining delay fiber under vibration be: e 3 = e 30 sin( ωt ),in e 30 =1×10 -5 , oh = 4000π rad / s. The length of the polarization-maintaining delay fiber is taken as... L = 500m, outer diameter r = 62.5μm, and the non-reciprocal phase difference is calculated by simulation according to equation (24). Figure 12 The relationship curve between the amplitude of the non-reciprocal phase difference and the bending radius of the optical fiber is given. Under the condition of optical fiber bending, the non-reciprocal phase difference caused by axial strain decreases with the increase of bending radius.

[0048] The effect of polarization-maintaining delay fiber beat length: Let the axial strain of the polarization-maintaining delay fiber under vibration be: e 3 = e 30 sin( ωt ),in e 30 =1×10 -5 , oh = 4000π rad / s. The length of the polarization-maintaining delay fiber is taken as... L = 500m, and the non-reciprocal phase difference is simulated and calculated according to equation (25). Figure 13The relationship curve between the amplitude of the non-reciprocal phase difference and the fiber beat length is given. The non-reciprocal phase difference caused by axial strain under fiber bending conditions decreases with the increase of fiber beat length.

[0049] The impact of the location of the disturbance: According to equations (20), (22), and (24), the non-reciprocal phase shift introduced by the vibration stress field is related to the location of the disturbance. The position sensitivity of the non-reciprocal phase difference under sinusoidal disturbance is: because ohl / c Since the distance from the vibration disturbance to the end of the sensing fiber is less than π / 2, the greater the non-reciprocal phase shift introduced. The point of strongest vibration sensitivity in the optical path system of the fiber optic current transformer is at the 45° fiber fusion point at the rear end of the polarizer.

[0050] Example 2: Furthermore, this invention also proposes a quantification calculation system 200 for vibration faults in all-fiber current transformers, such as... Figure 14 As shown, it includes: Modeling unit 201 is used to establish a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress for the polarization-maintaining optical path of the all-fiber current transformer. The first analysis unit 202 is used to select fiber micro-elements on the fiber transmission path based on the micro-element analysis model, and determine the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-element. The second analysis unit 203 is used to calculate the non-reciprocal phase difference under the action of vibration stress field based on the non-reciprocal phase difference model, the elastic-optical effect and the stress-strain effect, and to quantify the vibration fault of the all-fiber current transformer using the non-reciprocal phase difference.

[0051] Among them, based on the elasto-optical effect and the stress-strain effect, the non-reciprocal phase difference under the action of the vibration stress field is calculated, including: Based on the elastic-optical effect and the stress-strain effect, the changes in the refractive index and length of the optical fiber caused by time-varying stress are calculated. Based on the changes in the refractive index and length of the optical fiber caused by time-varying stress, the non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect are calculated respectively. The non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect is accumulated and integrated along the optical signal transmission path to calculate the non-reciprocal phase difference under the action of the vibration stress field.

[0052] The non-reciprocal phase difference introduced by the photoelastic effect is calculated, and the non-reciprocal phase difference introduced by the photoelastic effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference caused by the radial stress acting on the infinitesimal element due to the elasto-optic effect is calculated using the following formula: (1) Integrating equation (1) over the length of the polarization-maintaining delay fiber, we get: (2) The non-reciprocal phase difference caused by the axial stress acting on the infinitesimal element due to the elastic-optical effect is calculated using the following formula: (3) Integrating equation (3) over the length of the polarization-maintaining delay fiber, we get: (4) in, The non-reciprocal phase difference introduced by the photoelastic effect For refractive index, For Young's modulus, For fiber radius, The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Poisson's ratio, and The elastic coefficient is 1. Angular frequency, For time, The speed of light in a vacuum. The distance from the vibration location to the optical fiber. for Integral over the length of the polarization-maintaining delay fiber The bending radius of the optical fiber. The axial stress amplitude acting on the polarization-maintaining delay fiber under vibration conditions. This represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration conditions.

[0053] The non-reciprocal phase difference introduced by the stress-strain effect is calculated, and the non-reciprocal phase difference introduced by the stress-strain effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference between the two signal beams introduced by the stress-strain effect, accumulated through the infinitesimal element, is calculated using the following formula: (5) Integrating equation (5) over the length of the polarization-maintaining delay fiber, we get: (6) in, The non-reciprocal phase difference introduced by stress-strain effects and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Angular frequency, To the total length of the polarization-maintaining delay fiber, The distance from the vibration location to the optical fiber. The speed of light in a vacuum. is the refractive index.

[0054] The formula for calculating the non-reciprocal phase difference under the action of the vibration stress field is as follows: (7) in, This refers to the non-reciprocal phase difference under the action of a vibrational stress field. The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. For refractive index, For Young's modulus, For fiber radius, Poisson's ratio, and The elastic coefficient is 1. λ is the wavelength of light in a vacuum. The bending radius of the optical fiber. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. To the total length of the polarization-maintaining delay fiber, The speed of light in a vacuum. Angular frequency, For time.

[0055] This invention can assess the impact parameters and degree of vibration on the current measurement of all-fiber current transformers, and then take corresponding measures to suppress the impact of vibration, providing a solution for designing highly vibration-resistant all-fiber current transformers.

[0056] Example 3: Based on the same inventive concept, this invention also provides a computer device, which includes a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to implement corresponding method flows or corresponding functions, thereby implementing the steps of the methods in the above embodiments.

[0057] Example 4: Based on the same inventive concept, this invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the steps of the method in the above embodiments.

[0058] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0059] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure one One or more processes and / or boxes Figure one A device that provides the functions specified in one or more boxes.

[0060] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure one One or more processes and / or boxes Figure one The function specified in one or more boxes.

[0061] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure one One or more processes and / or boxes Figure one The steps of the function specified in one or more boxes.

[0062] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0063] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for quantitative calculation of vibration faults in an all-fiber optic current transformer, characterized in that, include: For the polarization-maintaining optical path of an all-fiber current transformer, a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress is established. Based on the aforementioned micro-element analysis model, fiber micro-elements are selected along the fiber transmission path, and the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-element is determined. Based on the non-reciprocal phase difference model, the non-reciprocal phase difference under the action of vibration stress field is calculated based on the elasto-optic effect and stress-strain effect. The non-reciprocal phase difference is used to quantify the vibration fault of the all-fiber current transformer.

2. The method for quantitative calculation of vibration faults in all-fiber current transformers according to claim 1, characterized in that, The non-reciprocal phase difference calculated based on the elastic-optical effect and stress-strain effect under the action of vibrational stress field includes: Based on the elastic-optical effect and the stress-strain effect, the changes in the refractive index and length of the optical fiber caused by time-varying stress are calculated. Based on the changes in the refractive index and length of the optical fiber caused by time-varying stress, the non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect are calculated respectively. The non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect is accumulated and integrated along the optical signal transmission path to calculate the non-reciprocal phase difference under the action of the vibration stress field.

3. The method for quantitative calculation of vibration faults in all-fiber current transformers according to claim 2, characterized in that, The non-reciprocal phase difference introduced by the photoelastic effect is calculated, and the non-reciprocal phase difference introduced by the photoelastic effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference caused by the radial stress acting on the infinitesimal element due to the elasto-optic effect is calculated using the following formula: （1） Integrating equation (1) over the length of the polarization-maintaining delay fiber, we get: （2） The non-reciprocal phase difference caused by the axial stress acting on the infinitesimal element due to the elastic-optical effect is calculated using the following formula: （3） Integrating equation (3) over the length of the polarization-maintaining delay fiber, we get: （4） in, The non-reciprocal phase difference introduced by the photoelastic effect For refractive index, For Young's modulus, For fiber radius, The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Poisson's ratio, and The elastic coefficient is 1. Angular frequency, For time, The speed of light in a vacuum. The distance from the vibration location to the optical fiber. for Integral over the length of the polarization-maintaining delay fiber The bending radius of the optical fiber. The axial stress amplitude acting on the polarization-maintaining delay fiber under vibration conditions. This represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration conditions.

4. The method for quantitative calculation of vibration faults in all-fiber current transformers according to claim 2, characterized in that, The non-reciprocal phase difference introduced by the stress-strain effect is calculated, and the non-reciprocal phase difference introduced by the stress-strain effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference between the two signal beams introduced by the stress-strain effect, accumulated through the infinitesimal element, is calculated using the following formula: （5） Integrating equation (5) over the length of the polarization-maintaining delay fiber, we get: （6） in, The non-reciprocal phase difference introduced by stress-strain effects and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Angular frequency, To the total length of the polarization-maintaining delay fiber, The distance from the vibration location to the optical fiber. The speed of light in a vacuum. is the refractive index.

5. The method for quantitative calculation of vibration faults in all-fiber current transformers according to claim 2, characterized in that, The formula for calculating the non-reciprocal phase difference under the action of the vibration stress field is as follows: （7） in, This refers to the non-reciprocal phase difference under the action of a vibrational stress field. The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. For refractive index, For Young's modulus, For fiber radius, Poisson's ratio, and The elastic coefficient is 1. λ is the wavelength of light in a vacuum. The bending radius of the optical fiber. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. To the total length of the polarization-maintaining delay fiber, The speed of light in a vacuum. Angular frequency, For time.

6. A quantitative calculation system for vibration faults in an all-fiber optic current transformer, characterized in that, include: The modeling unit is used to establish a micro-element analysis model of the polarization-maintaining fiber of the all-fiber current transformer under vibration stress for the polarization-maintaining optical path of the all-fiber current transformer. The first analysis unit is used to select fiber micro-elements on the fiber transmission path based on the micro-element analysis model, and determine the non-reciprocal phase difference model introduced by the optical path change of the fiber micro-element. The second analysis unit is used to calculate the non-reciprocal phase difference under the action of vibration stress field based on the non-reciprocal phase difference model, the elastic-optical effect and the stress-strain effect, and to quantify the vibration fault of the all-fiber current transformer using the non-reciprocal phase difference.

7. The all-fiber optic current transformer vibration fault quantification calculation system according to claim 6, characterized in that, The non-reciprocal phase difference calculated based on the elastic-optical effect and stress-strain effect under the action of vibrational stress field includes: Based on the elastic-optical effect and the stress-strain effect, the changes in the refractive index and length of the optical fiber caused by time-varying stress are calculated. Based on the changes in the refractive index and length of the optical fiber caused by time-varying stress, the non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect are calculated respectively. The non-reciprocal phase difference introduced by the elastic-optical effect and the stress-strain effect is accumulated and integrated along the optical signal transmission path to calculate the non-reciprocal phase difference under the action of the vibration stress field.

8. The all-fiber optic current transformer vibration fault quantification calculation system according to claim 7, characterized in that, The non-reciprocal phase difference introduced by the photoelastic effect is calculated, and the non-reciprocal phase difference introduced by the photoelastic effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference caused by the radial stress acting on the infinitesimal element due to the elasto-optic effect is calculated using the following formula: （1） Integrating equation (1) over the length of the polarization-maintaining delay fiber, we get: （2） The non-reciprocal phase difference caused by the axial stress acting on the infinitesimal element due to the elastic-optical effect is calculated using the following formula: （3） Integrating equation (3) over the length of the polarization-maintaining delay fiber, we get: （4） in, The non-reciprocal phase difference introduced by the photoelastic effect For refractive index, For Young's modulus, For fiber radius, The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Poisson's ratio, and The elastic coefficient is 1. Angular frequency, For time, The speed of light in a vacuum. The distance from the vibration location to the optical fiber. for Integral over the length of the polarization-maintaining delay fiber The bending radius of the optical fiber. The axial stress amplitude acting on the polarization-maintaining delay fiber under vibration conditions. This represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration conditions.

9. The all-fiber optic current transformer vibration fault quantification calculation system according to claim 7, characterized in that, The non-reciprocal phase difference introduced by the stress-strain effect is calculated, and the non-reciprocal phase difference introduced by the stress-strain effect is accumulated and integrated along the optical signal transmission path, including: The non-reciprocal phase difference between the two signal beams introduced by the stress-strain effect, accumulated through the infinitesimal element, is calculated using the following formula: （5） Integrating equation (5) over the length of the polarization-maintaining delay fiber, we get: （6） in, The non-reciprocal phase difference introduced by stress-strain effects and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. λ is the wavelength of light in a vacuum. Angular frequency, To the total length of the polarization-maintaining delay fiber, The distance from the vibration location to the optical fiber. The speed of light in a vacuum. is the refractive index.

10. The all-fiber optic current transformer vibration fault quantification calculation system according to claim 7, characterized in that, The formula for calculating the non-reciprocal phase difference under the action of the vibration stress field is as follows: （7） in, This refers to the non-reciprocal phase difference under the action of a vibrational stress field. The radial stress amplitude acting on the polarization-maintaining delay fiber under vibration. For refractive index, For Young's modulus, For fiber radius, Poisson's ratio, and The elastic coefficient is 1. λ is the wavelength of light in a vacuum. The bending radius of the optical fiber. The value represents the strain amplitude caused by the axial stress acting on the polarization-maintaining delay fiber under vibration. and These are the refractive indices of the fast and slow axes of the polarization-maintaining delay fiber, respectively. To the total length of the polarization-maintaining delay fiber, The speed of light in a vacuum. Angular frequency, For time.

11. A computer device, characterized in that, include: One or more processors; A processor is used to execute one or more programs; When the one or more programs are executed by the one or more processors, the method described in any one of claims 1-5 is implemented.

12. A computer-readable storage medium, characterized in that, It contains a computer program, which, when executed, implements the method as described in any one of claims 1-5.

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