Capacitive voltage transformer voltage measurement method and system based on quantum phase difference

Abstract

The invention relates to the technical field of capacitor voltage transformers, and discloses a capacitor voltage transformer voltage measurement method and system based on quantum phase difference. The method comprises the following steps: determining a quantum phase difference by coupling a vertical axial magnetic field, and calculating a population difference according to preset fluorescence intensity, a fluorescence conversion coefficient and excitation photon flux; and finally, by taking the population difference, the quantum phase difference, the axial magnetic field and the CVT capacitance parameter as input, completing the rapid calculation of the instantaneous voltage. According to the method, errors caused by electromagnetic interference and element aging in traditional calculation are effectively reduced, the instantaneous voltage calculation precision is guaranteed while the response speed is increased, and reliable voltage data support is provided for transient stability control and rapid fault positioning of a power system. The technical problem of voltage monitoring data distortion caused by the fact that a traditional CVT cannot effectively monitor rapid transient events such as line voltage transient sag is solved.

Description

Technical Field

[0001] This invention relates to the field of capacitive voltage transformer technology, and in particular to a method and system for measuring voltage in a capacitive voltage transformer based on quantum phase difference. Background Technology

[0002] Capacitor voltage transformers (CVTs) are key devices in power systems for monitoring bus and line voltages. Their voltage measurement function is based on the principle of capacitive voltage division. During operation, the voltage signal from the high-voltage bus or line is first applied across the series capacitor divider. According to the law of capacitive voltage division, the high-voltage capacitor unit and the medium-voltage capacitor unit divide the original high-voltage signal according to the capacitance ratio, resulting in a lower voltage signal output from the medium-voltage capacitor unit that meets the input requirements of the intermediate transformer. Subsequently, this low-voltage signal is further stepped down by the intermediate transformer, the reactive power of the capacitor is offset by the compensation reactor, and the resonance is suppressed by the damping device before finally being output to the secondary measurement circuit or protection device. This completes the monitoring and acquisition of bus and line voltages. Due to its controllable cost and excellent insulation performance, this measurement method has been widely used in power systems at all levels.

[0003] However, existing voltage measurement methods mainly rely on traditional voltage monitoring systems centered around CVTs. These systems continuously acquire voltage signals via CVTs and transmit them to a backend monitoring system to achieve real-time monitoring of parameters such as voltage amplitude and frequency, while also providing voltage reference signals for relay protection devices. However, these methods are limited by the capacitive voltage divider mechanism, resulting in significant defects in their transient response performance: the inherent inertia of capacitive elements in response to instantaneous voltage changes leads to a weak ability of CVTs to capture voltage transients. This makes traditional CVTs unable to effectively monitor rapid transient events such as instantaneous voltage drops in the line, resulting in distorted voltage monitoring data. Summary of the Invention

[0004] This invention provides a voltage measurement method and system for capacitive voltage transformers based on quantum phase difference, which solves the technical problem that the inherent inertia of capacitive elements in response to instantaneous voltage changes in the prior art leads to the weak ability of CVT to capture voltage transient processes, making it impossible for traditional CVT to effectively monitor rapid transient events such as instantaneous voltage drops in the line, resulting in distorted voltage monitoring data.

[0005] The first aspect of this invention provides a voltage measurement method for a capacitive voltage transformer based on quantum phase difference, comprising:

[0006] Obtain the instantaneous current of the line where the capacitive voltage transformer is located and the axial magnetic field corresponding to the instantaneous current;

[0007] The spin Hamiltonian is determined based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect between the preset optical field and the quantum spin.

[0008] The quantum phase difference is determined based on the axial magnetic field and the spin Hamiltonian;

[0009] The population difference is determined based on the preset fluorescence intensity, preset fluorescence conversion coefficient, and excitation photon flux.

[0010] The instantaneous voltage of the capacitive voltage transformer is calculated based on the population difference, the quantum phase difference, the axial magnetic field, and the capacitance parameters of the capacitive voltage transformer.

[0011] Optionally, obtaining the instantaneous current of the line where the capacitive voltage transformer is located and the axial magnetic field corresponding to the instantaneous current includes:

[0012] Collect the instantaneous current of the line where the capacitive voltage transformer is located;

[0013] The axial magnetic field generated by the instantaneous current was calculated using Biosavart's law.

[0014] Optionally, determining the spin Hamiltonian based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin includes:

[0015] The Zeeman splitting effect of the axial magnetic field on the quantum spin energy level is determined based on the effect of the axial magnetic field on the energy level spacing between the quantum ground state and the quantum excited state.

[0016] Based on the axial magnetic field and the preset photon spin coupling coefficient, the coupling effect between the preset optical field and the quantum spin is determined;

[0017] The spin Hamiltonian of the nitrogen-vacancy color center is determined based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin.

[0018] Optionally, determining the quantum phase difference based on the axial magnetic field and the spin Hamiltonian includes:

[0019] Based on the Schrödinger equation, the spin state of the nitrogen-vacancy color center is evolved according to the axial magnetic field and the spin Hamiltonian to generate a quantum state containing phase information;

[0020] The phase difference of the quantum state containing phase information is calculated using Ramsey interferometry to generate a quantum phase difference;

[0021] The relationship between the quantum phase difference and the axial magnetic field is constructed using the quantum phase difference and the axial magnetic field.

[0022] Optionally, determining the population difference based on a preset fluorescence intensity, a preset fluorescence conversion coefficient, and an excitation photon flux includes:

[0023] Based on the fluorescence characteristics of the nitrogen-vacancy color center, a preset fluorescence intensity is collected using a single-photon detector;

[0024] The population difference is calculated using the preset fluorescence intensity, optical efficiency, preset fluorescence conversion coefficient, and excitation photon flux.

[0025] Optionally, it also includes:

[0026] The quantum phase difference is converted into a population difference by a preset microwave pulse;

[0027] The relationship between the population difference and the quantum phase difference is constructed using the population difference and the quantum phase difference.

[0028] Optionally, calculating the instantaneous voltage of the capacitive voltage transformer based on the population difference, the quantum phase difference, the axial magnetic field, and the capacitance parameters of the capacitive voltage transformer includes:

[0029] The relationship between the population difference and the axial magnetic field is determined based on the relationship between the population difference and the quantum phase difference, and the relationship between the quantum phase difference and the axial magnetic field.

[0030] Based on the relationship between the population difference and the axial magnetic field, the instantaneous axial magnetic field of the capacitive voltage transformer is calculated using the capacitance parameters of the capacitive voltage transformer.

[0031] The instantaneous voltage of the capacitive voltage transformer is calculated using the capacitance parameters of the capacitive voltage transformer and the instantaneous axial magnetic field.

[0032] A second aspect of the present invention provides a voltage measurement system for a capacitive voltage transformer based on quantum phase difference, comprising:

[0033] The acquisition module is used to acquire the instantaneous current of the line where the capacitive voltage transformer is located and the axial magnetic field corresponding to the instantaneous current;

[0034] The spin Hamiltonian module is used to determine the spin Hamiltonian based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin.

[0035] A quantum phase difference module is used to determine the quantum phase difference based on the axial magnetic field and the spin Hamiltonian;

[0036] The population difference module is used to determine the population difference according to the preset fluorescence intensity, preset fluorescence conversion coefficient and excitation photon flux.

[0037] The calculation module is used to calculate the instantaneous voltage of the capacitive voltage transformer based on the population difference, the quantum phase difference, the axial magnetic field, and the capacitance parameters of the capacitive voltage transformer.

[0038] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, implements the voltage measurement method for a capacitive voltage transformer based on quantum phase difference as described in any of the preceding claims.

[0039] The fourth aspect of the present invention provides a computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein, when the program instructions are executed by a computer, the computer performs the capacitive voltage transformer voltage measurement method based on quantum phase difference as described in any of the preceding claims.

[0040] As can be seen from the above technical solutions, the present invention has the following advantages:

[0041] This invention is based on the quantum spin effect and achieves accurate calculation of CVT instantaneous voltage through three key operations: First, the instantaneous current and corresponding axial magnetic field of the CVT circuit are acquired in real time to lay the data foundation; second, the spin Hamiltonian is constructed by combining the Zeeman splitting effect of the quantum spin energy level induced by the axial magnetic field with the preset optical field-quantum spin coupling effect, and then the quantum phase difference is determined by combining the axial magnetic field. At the same time, the population difference is calculated based on the preset fluorescence intensity, fluorescence conversion coefficient and excitation photon flux; finally, the instantaneous voltage is calculated rapidly using the population difference, quantum phase difference, axial magnetic field and CVT capacitance parameters as inputs. The entire process is based on establishing data correlation around quantum physical characteristics, breaking through the traditional CVT calculation logic that relies on electromagnetic induction.

[0042] This invention precisely addresses the technical pain point of slow transient response in CVTs: On the one hand, the computational path based on the quantum spin effect avoids the physical processes that cause response delays in traditional CVTs, such as the charging and discharging of electromagnetic components and the hysteresis of the iron core. The real-time correlation between the axial magnetic field and quantum parameters significantly shortens the data processing cycle, increasing the transient response speed to the microsecond level, and can accurately capture voltage transient changes during line current surges. On the other hand, the dual parameter calibration of population difference and quantum phase difference, combined with the personalized substitution of CVT capacitor parameters, effectively reduces the errors caused by electromagnetic interference and component aging in traditional calculations. While improving the response speed, it ensures the accuracy of instantaneous voltage calculation, providing reliable voltage data support for transient stability control and rapid fault location in power systems. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 The flowchart illustrates the steps of a capacitive voltage transformer voltage measurement method based on quantum phase difference, as provided in Embodiment 1 of the present invention.

[0045] Figure 2 This is a structural block diagram of a capacitive voltage transformer voltage measurement system based on quantum phase difference, provided in Embodiment 2 of the present invention. Detailed Implementation

[0046] This invention provides a voltage measurement method and system for capacitive voltage transformers based on quantum phase difference, which addresses the technical problem that the inherent inertia of capacitive elements in response to instantaneous voltage changes leads to weak ability of CVTs to capture voltage transient processes, making it impossible for traditional CVTs to effectively monitor rapid transient events such as instantaneous voltage drops in the line, resulting in distorted voltage monitoring data.

[0047] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0048] Please see Figure 1 , Figure 1 This is a flowchart illustrating the steps of a capacitive voltage transformer voltage measurement method based on quantum phase difference, as provided in Embodiment 1 of the present invention.

[0049] This invention provides a voltage measurement method for a capacitive voltage transformer based on quantum phase difference, comprising:

[0050] Step 101: Obtain the instantaneous current and the corresponding axial magnetic field of the line where the capacitive voltage transformer is located.

[0051] In this embodiment of the invention, a capacitive voltage transformer (CVT) refers to a core device in a power system used to monitor bus or line voltage.

[0052] instantaneous current , refers to the instantaneous value of the current flowing through the conductor at a specific moment t in the power line where the capacitive voltage transformer is located.

[0053] Axial magnetic field This refers to the instantaneous current The magnetic field generated when flowing through the conductor is aligned with the conductor's axis (or the direction of sensitivity of the quantum sensor).

[0054] There is no need to directly measure the instantaneous current of the CVT circuit using conventional equipment. This refers to the real-time current value of the line at a certain moment (including μs-level abrupt changes), but rather utilizes the magnetic effect of current—an instantaneous current generates a magnetic field around it, and the component of the magnetic field aligned with the conductor axis (or the sensitive direction of the quantum sensor) is the axial magnetic field. .

[0055] Furthermore, step 101 includes the following steps:

[0056] S11. Collect the instantaneous current of the line where the capacitive voltage transformer is located.

[0057] In this embodiment of the invention, the instantaneous current of the line where the CVT is located is obtained ( That is, the real-time current value of the line at a certain moment, including μs-level abrupt changes.

[0058] S12. Calculate the axial magnetic field generated by the instantaneous current using Biosavart's law.

[0059] In this embodiment of the invention, Biot-Savart's law refers to the core law in electromagnetism that describes "a current element generating a magnetic field".

[0060] Based on electromagnetic principles, the instantaneous current of the CVT circuit ( ) and axial magnetic field ( The key steps in establishing a quantitative correlation: due to instantaneous current When water flows through a conductor, it generates a magnetic field around the conductor. What is needed is an "axial magnetic field" that aligns with the conductor's axis (or the direction of sensitivity of a quantum sensor). Therefore, by integrating the magnetic field generated at the quantum sensor placement point by all current elements on the conductor using the Biot-Savart law (the integration path follows the magnetic flux concentrator loop to ensure accurate capture of the target region's magnetic field), the magnetic field at that point can be calculated due to the instantaneous current. The generated axial magnetic field The specific value.

[0061] Specifically, the current in the conductor generates an axial magnetic field according to the Biot-Savart law. :

[0062]

[0063] In the formula, Vacuum permeability: the constant that allows magnetic fields to conduct in a vacuum, and is a known value; Instantaneous current: Current that changes with time; Current element vector: A tiny line segment on a conductor, oriented in the same direction as the current, is a mathematical vector unit set according to the direction of the current, which can be directly obtained; Unit position vector: The direction vector from the current element to the magnetic field measurement point (NV color center position), a mathematical vector unit set with the current direction, which can be directly obtained; Distance: The straight-line distance from the current element to the magnetic field measurement point, which can be obtained directly; For closed-path integration: Line integral along the flux concentrator loop; the integration interval is obtained directly from the actual path. The vector cross product determines the direction of the magnetic field, indicating that it is perpendicular to the plane containing l and r.

[0064] Step 102: Determine the spin Hamiltonian based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect between the preset optical field and the quantum spin.

[0065] In this embodiment of the invention, the quantum spin energy level, specifically referring to the electron spin energy level of the diamond NV color center (nitrogen-vacancy color center), includes the ground state as its fundamental energy level. With excited state The energy level state changes with the external magnetic field.

[0066] The Zeeman splitting effect refers to the physical phenomenon that when an external magnetic field acts on a quantum spin energy level, the originally energy-degenerate (same energy) spin energy levels split, and the spacing between the split energy levels is proportional to the magnetic field strength. It is the core effect that establishes a correlation between the magnetic field and the quantum spin state.

[0067] The preset light field refers to the specific parameter light field set in this invention for manipulating the spin state of the NV color center. Specifically, it is a 532nm laser (used for spin state initialization) and a 637nm fluorescence probe light (used for reading the spin state population). Its frequency, intensity and other parameters are experimentally calibrated to suit the spin control requirements of the NV color center.

[0068] Quantum spin refers to the electron spin of the NV color center. It is a quantum state with intrinsic angular momentum, and its energy level state can be modulated by external magnetic fields or light fields. It is the core sensitive unit of quantum sensing.

[0069] The coupling effect refers to the energy and state interaction between the preset light field and the quantum spin of the NV color center. Specifically, the light field can excite the spin state to transition between different energy levels (such as a laser activating the spin state from the ground state). Stimulate (Energy level), and spin state transitions also exchange energy with the light field by emitting fluorescence (637nm).

[0070] The spin Hamiltonian H refers to the quantum mechanical equation describing the energy state of an NV color center quantum spin system. It can quantitatively characterize the combined influence of external magnetic fields (Zemann splitting effect) and light fields (coupling effect) on the spin energy level.

[0071] In a specific embodiment, the axial magnetic field is first defined. The target magnetic field component, calculated using the Biot-Savart law and generated by the instantaneous current of the CVT line, directly acts on the quantum spin energy level of the quantum sensing unit (diamond NV color center); based on the Zeeman splitting effect, the axial magnetic field... This will degenerate the original energy of the NV color center. and Spin energy levels split, and the spacing between the split energy levels increases with... The magnetic field strength increases linearly with the increase of the voltammetric magnetic field, and this effect becomes the core physical link that transforms the macroscopic magnetic field strength into quantum energy level differences. Simultaneously, combined with the optical field (532nm laser and 637nm fluorescence probe light) preset in this invention, this optical field will couple with the quantum spin of the NV color center—the 532nm laser can change the spin state from the ground state... Stimulate Energy level relaxation to Once the initialization is complete, the 637nm fluorescence probe light can read the population difference through the fluorescence intensity emitted by the spin state transition. This coupling provides a path for the manipulation and state reading of the quantum spin state. Based on the coupling between the Zeeman splitting effect of the axial magnetic field and the preset light field, the spin Hamiltonian describing the energy state of the NV color center spin system can be determined.

[0072] Further, step 102 includes the following sub-steps:

[0073] S21. Based on the influence of the axial magnetic field on the energy level spacing between the quantum ground state and the quantum excited state, determine the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level.

[0074] In this embodiment of the invention, the quantum ground state refers to the lowest energy state of the electron spin of the diamond NV color center (nitrogen-vacancy color center), corresponding to the spin state. It is the stable state of a quantum system when it is not disturbed by external forces, and it is also the target state after the spin state is initialized.

[0075] A quantum excited state refers to a state in diamond where the electron spin of the NV center is higher than the energy of the ground state, corresponding to the spin state. It needs to transition from the ground state under the influence of an external magnetic field or light field to form, and its energy is higher than that of the ground state and changes with the external magnetic field.

[0076] Energy level spacing refers to the quantum ground state ( ) and quantum excited state ( The energy difference between them, in the absence of an external magnetic field, and The energy level spacing is the same (i.e., the energy level is degenerate), and an external magnetic field will change this spacing.

[0077] First, let's clarify the axial magnetic field calculated using Biot-Savart's law. An electron spin system that acts on a quantum sensing unit (diamond NV color center), and the quantum spin energy level of this system includes the ground state. With excited state When there is no axial magnetic field, and In a state of energy level degeneracy (with the same energy level spacing); when the axial magnetic field When applied to this spin system, according to the coupling principle of electromagnetism and quantum mechanics, the magnetic field will exert a torque on the electron spin, breaking the original energy level degeneracy and causing the quantum ground state to change. With quantum excited state The energy level spacing between them varies The changes have occurred—specifically manifested as The greater the intensity, the greater the increase in the energy level spacing, and this increase is related to... The intensity is linearly proportional; by monitoring and quantifying this correspondence between the "change in axial magnetic field intensity and the change in energy level spacing", the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level can be determined.

[0078] S22. Based on the axial magnetic field and the preset photon spin coupling coefficient, determine the coupling effect between the preset optical field and the quantum spin.

[0079] In this embodiment of the invention, the preset photon spin coupling coefficient refers to a constant that is experimentally calibrated in advance and characterizes the interaction strength between the preset light field and the quantum spin. Its value is determined by the material properties of the quantum sensing unit (diamond NV color center) and the light field parameters (such as wavelength and intensity). It is a fixed known value and is used to quantitatively describe the energy exchange efficiency between the light field and the spin state.

[0080] The axial magnetic field has been determined based on the above information. The Zeeman splitting effect is generated in the quantum spin energy level, and the preset optical field (532nm laser and 637nm fluorescent probe light) needs to couple with the quantum spin (diamond NV center electron spin) to complete the quantum state manipulation. At this time, the preset photon spin coupling coefficient, which has been experimentally calibrated in advance, is combined with this. —This coefficient has been determined as a fixed value based on the material properties of the diamond NV color center and the wavelength and intensity parameters of the preset light field. It can quantitatively reflect the interaction intensity between the light field and the spin—that is, the coupling effect can be determined through the correlation between the two.

[0081] S23. Determine the spin Hamiltonian of the nitrogen-vacancy color center based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin.

[0082] In this embodiment of the invention, the nitrogen-vacancy color center refers to the defect structure formed by nitrogen atoms replacing carbon atoms in diamond and adjacent vacancies. Its electron spin is sensitive to magnetic and light fields and is the core functional unit for realizing quantum sensing in this invention.

[0083] Passed through axial magnetic field The effect of the quantum spin energy level of the NV color center determines the Zeeman splitting effect—that is ground state With excited state The energy level spacing varies with The intensity increases linearly, and the coupling effect is determined by the interaction between the preset light field (532nm laser, 637nm fluorescence detector light) and quantum spin—that is, the laser can initialize the spin state, the fluorescence detector light can capture the spin transition signal, and the interaction intensity between the two is determined by the preset photon spin coupling coefficient (…). Quantization (of experimentally calibrated fixed values); based on these two core physical effects, the spin Hamiltonian of the NV color center can be constructed, and its specific form is:

[0084]

[0085] In the formula, The spin Hamiltonian, measured in J (joules), is an important parameter in quantum mechanics; the first term This indicates the Zeeman splitting effect of the axial magnetic field on the spin energy level (which can lead to...). and Changes in the energy level spacing can alter the step number, thereby changing the quantum phase difference. (Second term) This indicates the coupling effect between the light field and the spin; The reduced Planck constant is a known number; Electron gyromagnetic ratio (characterizing the sensitivity of spin to a magnetic field, a material characteristic value, a known number); This is the axial magnetic field strength (a direct input quantity, measured by a flux concentrator). The z-component of the spin operator (describes the spin state of the NV color center, typically 0, 1, -1); is the photon-spin coupling coefficient, experimentally calibrated. For the generation and annihilation operators of photons; It is a spin-up / down operator (manipulating energy level transitions).

[0086] It is worth mentioning that the above formula mainly utilizes a diamond NV center spin-photon coupled sensing system, employing the quantum spin state of the diamond NV center as the magnetic field sensing unit, and achieving the quantum correlation between current, magnetic field, and voltage through the spin Hamiltonian H. In practical applications, laser photons emitted by a laser sensor irradiate the diamond quantum sensor, causing it to react, i.e., the so-called diamond NV center spin. When the diamond quantum sensor is placed in a magnetic field environment generated by current or voltage, the spin Hamiltonian H and axial magnetic field in the above formula will be formed. The calculation relationship is established, thereby creating a connection between macroscopic electromagnetic parameters and microscopic quantum parameters. (In practice, a pyramid-shaped diamond probe (tip size <100nm) can be fabricated using micro-nano fabrication technology, with the NV color center embedded in the probe tip, and photon-spin coupling transmission achieved through a tapered optical fiber.)

[0087] Step 103: Determine the quantum phase difference based on the axial magnetic field and the spin Hamiltonian.

[0088] In this embodiment of the invention, quantum phase difference refers to the difference between different spin states (such as NV color center quantum spin) when the NV color center quantum spin is in a superposition state. and Phase differences formed during the evolution process.

[0089] The previous text has already used axial magnetic field The spin Hamiltonian of the NV color center is determined by interaction with a preset light field, and this Hamiltonian clarifies... The energy perturbation law of spin energy levels; based on this, the spin state of the NV color center is first initialized to a superposition state by a π / 2 microwave pulse. and (existing simultaneously), at which point the two states are in phase; in the axial magnetic field ( Under continuous action, the spin system evolves according to the laws described by the spin Hamiltonian, because Through the Zeeman splitting effect and Energy level spacing varies Changes occur, and the rates of evolution between the two states differ over time. The quantum phase difference is then formed ( According to the principles of quantum mechanics, this phase difference is related to... The integral is directly related to ( , (electron gyromagnetic ratio), therefore, combined with the known axial magnetic field ( The quantum phase difference can be calculated by observing the changes in the quantum phase difference over time and the evolution of the spin Hamiltonian. ).

[0090] Furthermore, step 103 also includes the following sub-steps:

[0091] S31. Based on the Schrödinger equation, the spin state of the nitrogen-vacancy color center is evolved according to the axial magnetic field and the spin Hamiltonian to generate a quantum state containing phase information.

[0092] In this embodiment of the invention, the Schrödinger equation refers to the core equation in quantum mechanics that describes the evolution of the state of a quantum system over time, and can quantitatively characterize the dynamic changes of the quantum state under external influences (such as magnetic fields and light fields).

[0093] Spin state refers to the quantum state of the electron spin in the NV color center.

[0094] A quantum state containing phase information refers to a spin state that evolves under the influence of an axial magnetic field through the Schrödinger equation, where different spin components (such as...) represent the phase information of the quantum state. and A quantum state that has a phase difference due to energy level differences.

[0095] Axial magnetic field ( Driven spin evolution, specifically:

[0096] Axial magnetic field ( The spin energy level splits due to the Zeeman effect acting on the spin of the NV color center. The term in the spin Hamiltonian... The energy perturbation of the spin state by the magnetic field can be directly quantified.

[0097] The evolution of quantum states is described by the Schrödinger equation:

[0098]

[0099] In the formula, The axial magnetic field, as a coefficient of the spin Hamiltonian H, determines the evolution path of the system. For quantum state vectors (such as the spin state of the NV color center) , (i is the imaginary unit, and t is time).

[0100] S32. The phase difference of a quantum state containing phase information is calculated using Ramsey interferometry to generate a quantum phase difference.

[0101] In this embodiment of the invention, the Ramsey Interference Technique refers to the core technology in quantum mechanics used to accurately measure the phase difference of quantum states. Through the process of "initial pulse to prepare superposition state - free evolution to accumulate phase - secondary pulse to convert phase difference", the phase difference of quantum state is converted into a detectable state difference.

[0102] Specifically, quantum interference extracts quantum phase difference:

[0103] Ramsey interferometry: 1) Initial state preparation: The pulse prepares the spin state into a superposition state:

[0104]

[0105] 2) Free evolution: in the axial magnetic field Next evolution time Solving the Schrödinger equation yields:

[0106]

[0107] In the formula, Electron gyromagnetic ratio; The magnetic field is the axial magnetic field; i is the imaginary unit. , All are spin states of the NV color center.

[0108] 3) Quantum phase difference: the phase difference between different quantum states The quantum phase difference introduced for evolution.

[0109] S33. Using quantum phase difference and axial magnetic field, construct the relationship between quantum phase difference and axial magnetic field.

[0110] In this embodiment of the invention, an axial magnetic field is used. and quantum phase difference available:

[0111]

[0112] In the formula, Electron gyromagnetic ratio; The magnetic field is the axial magnetic field; i is the imaginary unit. , All are spin states of the NV color center; Evolution time.

[0113] Specifically, the quantum phase difference is the phase angle of the exponential term in the solution of the Schrödinger equation, which is directly related to the time-domain integral of the magnetic field. This relates the quantum phase difference to the axial magnetic field. Establish a mathematical relationship, that is, the phase difference caused by the instantaneous magnetic field:

[0114]

[0115] In the formula, Electron gyromagnetic ratio; It is an axial magnetic field; Evolution time.

[0116] It's worth noting that the above steps primarily establish the relationship between the macroscopic magnetic field and the microscopic quantum phase difference, providing a theoretical basis and the thought process behind this method for subsequent reverse inference. Because CVT voltage testing is insensitive to transient and transient voltage changes during voltage surges, it's difficult to detect equipment defects and power quality issues that voltage surges might indicate. This method leverages the sensitivity of quantum phase difference by placing diamond quantum sensors within the CVT's magnetic field. The quantum phase difference reflects changes in the magnetic field, allowing for the reverse inference of the CVT voltage. This enables highly sensitive voltage testing that can detect transient and transient states, thus revealing certain equipment defects.

[0117] Furthermore, this method also includes the following sub-steps:

[0118] S41. The quantum phase difference is converted into the population difference by a preset microwave pulse.

[0119] In this embodiment of the invention, the preset microwave pulse refers to a microwave pulse with pre-set parameters, specifically a frequency of 2.87 GHz. Microwave pulse.

[0120] Population difference refers to the different spin states (ground state) of the NV color center. With excited state The difference in the proportion of particles.

[0121] In step S32, the Ramsey interference technique is used to generate a quantum phase difference. The technique for generating the quantum phase difference can be further refined as follows:

[0122] Laser initialization: A 532nm laser pulse (50ns duration) initializes the NV color center ground state. Stimulate The energy level then relaxes to the spin state. (Population number>90%).

[0123] Microwave excitation: applying Microwave pulse (frequency 2.87 GHz, duration) By superimposing spin states, we can obtain:

[0124]

[0125] In the formula, , All are spin states of the NV color center.

[0126] Free evolution: in axial magnetic field Next evolution time Accumulate quantum phase difference:

[0127]

[0128] In the formula, Electron gyromagnetic ratio; Evolutionary time; It is an axial magnetic field.

[0129] Secondary microwave pulse: Apply another The pulse converts the quantum phase difference into a population difference.

[0130] S42. Using population difference and quantum phase difference, construct the relationship between population difference and quantum phase difference.

[0131] In this embodiment of the invention, the relationship between population difference and quantum phase difference is as follows:

[0132]

[0133] In the formula, The difference in population size; For quantum phase difference; Electron gyromagnetic ratio; Evolutionary time; It is an axial magnetic field.

[0134] Step 104: Determine the population difference according to the preset fluorescence intensity, preset fluorescence conversion coefficient and excitation photon flux.

[0135] In this embodiment of the invention, the preset fluorescence intensity refers to the intensity of the fluorescence signal emitted during the spin state transition of the NV color center, which is collected by a single-photon detector.

[0136] Preset fluorescence conversion coefficient refers to the pre-calibrated fluorescence conversion coefficient, which characterizes the single spin of the NV center from the excited state. Transition back to ground state A constant representing the average number of photons emitted per hour.

[0137] Excitation photon flux refers to the number of excitation laser photons that irradiate the NV color center per unit time.

[0138] Population was detected using fluorescence:

[0139] 1) Spin state When the electron returns to the ground state, it emits fluorescence (wavelength 637 nm), while The state is mainly transitioned through nonradiative transitions.

[0140] 2) Population difference With fluorescence intensity Proportional:

[0141]

[0142] In the formula, The fluorescence photon count rate (acquired by a single-photon detector); Fluorescence intensity (unit: photons / second) is the number of fluorescence photons received by the detector per second, which directly reflects the quantum state population of the spin state of the NV color center, and is a set value. The optical collection efficiency (dimensionless, ranging from 0 to 1) represents the proportion of fluorescent photons captured by the detection system, which depends on the numerical aperture (NA) of the optical lens and the fiber coupling efficiency. For example, when NA = 0.8, ; The fluorescence conversion coefficient (unit: photons / spin) is the coefficient of a single NV color center from... State transition The average number of photons emitted during the spin state is typically about 0.3 photons / spin, which is a known number; , Let be the population probability of the spin state (dimensionless), where The NV color center is in the ground state. The probability, In an excited state The probability is initialized using a 532nm laser, making After microwave pulse manipulation, With axial magnetic field change; To excite photon flux (unit: photons / second), the number of photons per second that the excitation laser irradiates the NV color center, a typical value. ph / s; This indicates that the fluorescence intensity depends on the population difference between the ground state and the excited state, and this difference is determined by the external axial magnetic field. Modulation (via the Zeeman effect).

[0143] Furthermore, step 104 includes the following sub-steps:

[0144] S51. Based on the fluorescence characteristics of nitrogen-vacancy color centers, a preset fluorescence intensity is collected by a single-photon detector.

[0145] In this embodiment of the invention, fluorescence characteristics refer to the luminescence characteristics of NV color centers under external light field excitation.

[0146] A single-photon detector is a highly sensitive detection device used to capture fluorescent photons emitted by NV color centers. It can count a single 637nm fluorescent photon and output an electrical signal proportional to the number of photons.

[0147] Utilizing the fluorescence properties of NV color centers— The state transition emits 637nm fluorescence. The state emits almost no light. Immediately after applying a second preset microwave pulse, the NV color center is illuminated with 637nm fluorescence probe light. When a particle undergoes an excited transition, it emits fluorescence. These particles do not produce significant fluorescence; the fluorescence signal is collected using a single-photon detector, and the total number of fluorescent photons detected within a preset time window is counted to obtain the preset fluorescence intensity. .

[0148] S52. Calculate the population difference using preset fluorescence intensity, optical efficiency, preset fluorescence conversion coefficient, and excitation photon flux.

[0149] In this embodiment of the invention, optical efficiency refers to a pre-defined constant characterizing the proportion of fluorescent photons captured by the detection system (including lenses and optical fibers), which is dimensionless (with a value of 0 to 1).

[0150] The fluorescence properties of the NV color center have been utilized to obtain the preset fluorescence intensity I_f using a single-photon detector, and the optical efficiency is known. Preset fluorescence conversion coefficient Excitation photon flux All are pre-calibrated or set fixed parameters, combined with NV color centers. The state transition emits 637nm fluorescence. The characteristic of "almost no emission" is based on the pre-defined correlation formula between fluorescence intensity and population difference in this invention. The formula is transformed and derived to reflect the actual measured values. With known , , Substituting into the calculation, we obtain the population difference. .

[0151] Step 105: Calculate the instantaneous voltage of the capacitive voltage transformer based on the population difference, quantum phase difference, axial magnetic field, and capacitance parameters of the capacitive voltage transformer.

[0152] In this embodiment of the invention, the capacitance parameter refers to the nominal capacitance value (in farads) of the voltage divider capacitor in the CVT, which is determined by the equipment design and is known in advance.

[0153] Instantaneous voltage refers to the voltage value (in volts) of the line where the CVT is located at a certain moment, and the instantaneous current of the line ( This is related to line impedance.

[0154] Population difference has been used Inversely deducing the quantum phase difference ( ), combined with the integral relationship between quantum phase difference and axial magnetic field ( ),right The instantaneous axial magnetic field is obtained by taking the time derivative. ;Depend on With CVT line instantaneous current Relationship ( (This can be obtained through engineering approximation) = That is, the instantaneous voltage of the line With instantaneous current The differential relationship between the capacitance parameter C and the capacitance parameter C is determined by calculation. The instantaneous voltage of the CVT can then be obtained. .

[0155] Furthermore, step 105 also includes the following sub-steps:

[0156] S61. Determine the relationship between the population difference and the axial magnetic field based on the relationship between the population difference and the quantum phase difference, and the relationship between the quantum phase difference and the axial magnetic field.

[0157] In this embodiment of the invention, the relationship between the population difference and the quantum phase difference is as follows:

[0158]

[0159] The relationship between quantum phase difference and axial magnetic field:

[0160]

[0161] get:

[0162]

[0163] In the formula, The difference in population size; For quantum phase difference; Electron gyromagnetic ratio; Evolutionary time; It is an axial magnetic field.

[0164] S62. Based on the relationship between population difference and axial magnetic field, the instantaneous axial magnetic field of the capacitive voltage transformer is calculated using the capacitance parameters of the capacitive voltage transformer.

[0165] In this embodiment of the invention, the instantaneous axial magnetic field is inverted:

[0166]

[0167] Depend on

[0168] Engineering approximation =

[0169] In the formula, The difference in population size; For quantum phase difference; Electron gyromagnetic ratio; Evolutionary time; It is an axial magnetic field; Inverse cosine function By differentiating with respect to time t, the rate of change of the quantum phase difference with time can be obtained. The vacuum permeability; It is a current element vector; It is the unit vector pointing from the current element to the field point; The distance from the current element to the field point; These are the capacitance parameters of the CVT.

[0170] S63. Using the capacitance parameters and instantaneous axial magnetic field of the capacitive voltage transformer, calculate the instantaneous voltage of the capacitive voltage transformer.

[0171] In this embodiment of the invention, the instantaneous voltage value of the CVT is:

[0172]

[0173] In the formula, It is an axial magnetic field; The vacuum permeability; The distance from the current element to the field point; These are the capacitance parameters of the CVT.

[0174] By directly inferring voltage from the population using the above method, the inertia of the CVT capacitor on voltage can be bypassed, thus solving the problem of transient signal loss caused by capacitor charging and discharging delays (bandwidth ≤ 1kHz). It can detect μs-level arc reignition or ferroresonance, and can achieve 15kV / μs steep-wave overvoltage capture (such as circuit breaker operation transients) and ferroresonance identification (500ns oscillation, accuracy > 97%), etc., causing transient voltage changes.

[0175] It is worth mentioning that, since the voltage is derived by inversely calculating the quantum population, which belongs to the microscopic realm and is extremely sensitive to change, the CVT voltage obtained by this method can reflect instantaneous voltage harmonic waveforms with a period of 1ns in the laboratory. In engineering practice, it is also sufficient to reflect harmonics with a period of 100ns. According to the Nyquist sampling theorem, this sensor can directly sample voltage harmonics with a period of more than 200ns. Therefore, it can capture voltage instantaneous changes caused by faults such as 15kV / μs steep overvoltage capture (e.g., transient circuit breaker operation) and ferroresonant identification (500ns oscillation, accuracy >97%).

[0176] Please see Figure 2 , Figure 2 This is a structural block diagram of a capacitive voltage transformer voltage measurement system based on quantum phase difference, provided in Embodiment 2 of the present invention.

[0177] This invention provides a voltage measurement system for a capacitive voltage transformer based on quantum phase difference, comprising:

[0178] The acquisition module 201 is used to acquire the instantaneous current and the corresponding axial magnetic field of the line where the capacitive voltage transformer is located.

[0179] Spin Hamiltonian module 202 is used to determine the spin Hamiltonian based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field and the quantum spin.

[0180] Quantum phase difference module 203 is used to determine the quantum phase difference based on the axial magnetic field and the spin Hamiltonian;

[0181] The population difference module 204 is used to determine the population difference according to the preset fluorescence intensity, preset fluorescence conversion coefficient and excitation photon flux.

[0182] The calculation module 205 is used to calculate the instantaneous voltage of the capacitive voltage transformer based on the population difference, quantum phase difference, axial magnetic field and capacitance parameters of the capacitive voltage transformer.

[0183] Furthermore, the acquisition module 201 includes:

[0184] The acquisition submodule is used to acquire the instantaneous current of the line where the capacitive voltage transformer is located;

[0185] The Biosavart law submodule is used to calculate the axial magnetic field generated by an instantaneous current using Biosavart law.

[0186] Furthermore, the spin Hamiltonian module 202 includes:

[0187] The influence submodule is used to determine the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level based on the change in the energy level spacing between the quantum ground state and the quantum excited state caused by the axial magnetic field.

[0188] The coupling submodule is used to determine the coupling effect between a preset optical field and a quantum spin based on the axial magnetic field and the preset photon spin coupling coefficient.

[0189] The spin Hamiltonian module is used to determine the spin Hamiltonian of the nitrogen-vacancy color center based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin.

[0190] Furthermore, the quantum phase difference module 203 includes:

[0191] The quantum state module is used to evolve the spin state of the nitrogen-vacancy color center based on the Schrödinger equation, according to the axial magnetic field and the spin Hamiltonian, to generate a quantum state containing phase information.

[0192] The computational submodule is used to calculate the phase difference of a quantum state containing phase information using Ramsey interferometry, and to generate a quantum phase difference;

[0193] The first construction submodule is used to construct the relationship between the quantum phase difference and the axial magnetic field.

[0194] Furthermore, the population difference module 204 includes:

[0195] The fluorescence intensity submodule is used to collect preset fluorescence intensities using a single-photon detector based on the fluorescence characteristics of nitrogen-vacancy color centers.

[0196] The population difference calculation submodule is used to calculate the population difference using preset fluorescence intensity, optical efficiency, preset fluorescence conversion coefficient, and excitation photon flux.

[0197] Furthermore, this system also includes:

[0198] The conversion submodule is used to convert quantum phase difference into population difference using preset microwave pulses;

[0199] The second construction submodule is used to construct the relationship between population difference and quantum phase difference using population difference and quantum phase difference.

[0200] Furthermore, the computing module 205 includes:

[0201] The third construction submodule is used to determine the relationship between the population difference and the axial magnetic field based on the relationship between the population difference and the quantum phase difference, and the relationship between the quantum phase difference and the axial magnetic field.

[0202] The instantaneous axial magnetic field calculation submodule is used to calculate the instantaneous axial magnetic field of a capacitive voltage transformer based on the relationship between the population difference and the axial magnetic field, using the capacitance parameters of the capacitive voltage transformer.

[0203] The instantaneous voltage calculation submodule is used to calculate the instantaneous voltage of a capacitive voltage transformer using the capacitance parameters and instantaneous axial magnetic field of the capacitive voltage transformer.

[0204] Embodiment 3 of the present invention provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed, it implements the voltage measurement method of a capacitive voltage transformer based on quantum phase difference as described in any embodiment of the present invention.

[0205] Embodiment 4 of the present invention provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer performs a voltage measurement method for a capacitive voltage transformer based on quantum phase difference as described in any embodiment of the present invention.

[0206] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0207] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0208] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0209] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0210] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0211] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for measuring voltage in a capacitive voltage transformer based on quantum phase difference, characterized in that, include: Obtain the instantaneous current of the line where the capacitive voltage transformer is located and the axial magnetic field corresponding to the instantaneous current; The spin Hamiltonian is determined based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect between the preset optical field and the quantum spin. The quantum phase difference is determined based on the axial magnetic field and the spin Hamiltonian; The population difference is determined based on the preset fluorescence intensity, preset fluorescence conversion coefficient, and excitation photon flux. The instantaneous voltage of the capacitive voltage transformer is calculated based on the population difference, the quantum phase difference, the axial magnetic field, and the capacitance parameters of the capacitive voltage transformer.

2. The voltage measurement method for capacitive voltage transformers based on quantum phase difference according to claim 1, characterized in that, The acquisition of the instantaneous current of the line where the capacitive voltage transformer is located and the corresponding axial magnetic field of the instantaneous current includes: Collect the instantaneous current of the line where the capacitive voltage transformer is located; The axial magnetic field generated by the instantaneous current was calculated using Biosavart's law.

3. The voltage measurement method for capacitive voltage transformers based on quantum phase difference according to claim 1, characterized in that, The determination of the spin Hamiltonian based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin includes: The Zeeman splitting effect of the axial magnetic field on the quantum spin energy level is determined based on the effect of the axial magnetic field on the energy level spacing between the quantum ground state and the quantum excited state. Based on the axial magnetic field and the preset photon spin coupling coefficient, the coupling effect between the preset optical field and the quantum spin is determined; The spin Hamiltonian of the nitrogen-vacancy color center is determined based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin.

4. The voltage measurement method for a capacitive voltage transformer based on quantum phase difference according to claim 3, characterized in that, The determination of the quantum phase difference based on the axial magnetic field and the spin Hamiltonian includes: Based on the Schrödinger equation, the spin state of the nitrogen-vacancy color center is evolved according to the axial magnetic field and the spin Hamiltonian to generate a quantum state containing phase information; The phase difference of the quantum state containing phase information is calculated using Ramsey interferometry to generate a quantum phase difference; The relationship between the quantum phase difference and the axial magnetic field is constructed using the quantum phase difference and the axial magnetic field.

5. The voltage measurement method for a capacitive voltage transformer based on quantum phase difference according to claim 4, characterized in that, The determination of the population difference based on preset fluorescence intensity, preset fluorescence conversion coefficient, and excitation photon flux includes: Based on the fluorescence characteristics of the nitrogen-vacancy color center, a preset fluorescence intensity is collected using a single-photon detector; The population difference is calculated using the preset fluorescence intensity, optical efficiency, preset fluorescence conversion coefficient, and excitation photon flux.

6. The voltage measurement method for a capacitive voltage transformer based on quantum phase difference according to claim 4, characterized in that, Also includes: The quantum phase difference is converted into a population difference by a preset microwave pulse; The relationship between the population difference and the quantum phase difference is constructed using the population difference and the quantum phase difference.

7. The voltage measurement method for a capacitive voltage transformer based on quantum phase difference according to claim 6, characterized in that, The calculation of the instantaneous voltage of the capacitive voltage transformer based on the population difference, the quantum phase difference, the axial magnetic field, and the capacitance parameters of the capacitive voltage transformer includes: The relationship between the population difference and the axial magnetic field is determined based on the relationship between the population difference and the quantum phase difference, and the relationship between the quantum phase difference and the axial magnetic field. Based on the relationship between the population difference and the axial magnetic field, the instantaneous axial magnetic field of the capacitive voltage transformer is calculated using the capacitance parameters of the capacitive voltage transformer. The instantaneous voltage of the capacitive voltage transformer is calculated using the capacitance parameters of the capacitive voltage transformer and the instantaneous axial magnetic field.

8. A voltage measurement system for a capacitive voltage transformer based on quantum phase difference, characterized in that, include: The acquisition module is used to acquire the instantaneous current of the line where the capacitive voltage transformer is located and the axial magnetic field corresponding to the instantaneous current; The spin Hamiltonian module is used to determine the spin Hamiltonian based on the Zeeman splitting effect of the axial magnetic field on the quantum spin energy level and the coupling effect of the preset optical field with the quantum spin. A quantum phase difference module is used to determine the quantum phase difference based on the axial magnetic field and the spin Hamiltonian; The population difference module is used to determine the population difference according to the preset fluorescence intensity, preset fluorescence conversion coefficient and excitation photon flux. The calculation module is used to calculate the instantaneous voltage of the capacitive voltage transformer based on the population difference, the quantum phase difference, the axial magnetic field, and the capacitance parameters of the capacitive voltage transformer.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the voltage measurement method for a capacitive voltage transformer based on quantum phase difference as described in any one of claims 1-7.

10. A computer program product, characterized in that, The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, wherein when the program instructions are executed by a computer, the computer performs the voltage measurement method for a capacitive voltage transformer based on quantum phase difference as described in any one of claims 1-7.

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