A low-loss transmission method and system for current transformer signals

Abstract

The present invention provides a low-loss transmission method and system for current transformer signals, relating to the field of electrical measurement technology. The method comprises: obtaining the internal temperature of the current transformer and a primary conductor current sensing signal on the high-voltage side; restoring the primary conductor current sensing signal to the primary conductor true current using an integrator with an adaptive damping core; obtaining the light source wavelength drift of the current transformer laser light source according to the internal temperature of the current transformer; introducing information entropy to optimize the laser light source modulation parameters of the current transformer photoelectric modulator based on the primary conductor true current, the light source wavelength drift, and the total length of the current transformer transmission optical fiber; modulating the primary conductor true current into an optical signal based on the laser light source modulation parameters; transmitting the optical signal to a current transformer demodulation module on the low-voltage side for signal restoration to obtain the primary conductor restored current; thus, low-loss transmission of the current transformer signal and measurement accuracy of the primary conductor can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical measurement and identification, and in particular to a low-loss transmission method and system for current transformer signals. Background Art

[0002] An electronic current transformer (ECT or E-CVT) is an intelligent instrument that uses sensors and electronic circuits instead of traditional iron-core coils to sample, transform, and output the current of a primary high-voltage conductor. With advantages such as compact size, high bandwidth, strong anti-interference capabilities, and ease of digitization, it is widely used in smart grids, high-voltage transmission, and substation monitoring.

[0003] Electronic current transformers rely on photoelectric modulation to convert the high-voltage side current signal into an optical signal for transmission to the low-voltage side. However, over long-distance fiber optic transmission, factors such as temperature drift, wavelength offset, laser modulation mismatch, and nonlinear losses can lead to signal amplitude attenuation and waveform distortion. Failure to control these losses will directly affect the accuracy of primary current restoration, leading to measurement errors, protection failures, misdiagnosis of faults, and other power system safety risks. Therefore, minimizing current transformer signal loss is crucial to ensuring transformer accuracy and system stability.

[0004] However, the existing current transformer signal transmission process usually relies on fixed parameter modulation and static wavelength configuration, which makes it difficult to adapt to dynamic interference such as current mutation or temperature drift. It is easy to cause signal amplitude attenuation and waveform distortion during transmission, which can easily lead to serious inaccuracy in the measurement accuracy of primary conductor current. Summary of the Invention

[0005] In order to solve the technical problems in the prior art that the transmission process of existing current transformer signals usually relies on fixed parameter modulation and static wavelength configuration, is difficult to adapt to dynamic interference such as current mutation or temperature drift, easily leads to signal amplitude attenuation and waveform distortion during transmission, and easily leads to serious inaccuracy in the measurement accuracy of primary conductor current, the present invention provides a low-loss transmission method and system for current transformer signals.

[0006] The technical solutions provided by the embodiments of the present invention are as follows:

[0007] First aspect

[0008] An embodiment of the present invention provides a low-loss transmission method for current transformer signals, which is applied to an electronic current transformer. The method includes:

[0009] S1: Obtain the internal temperature of the current transformer and the primary conductor current sensing signal on the high voltage side;

[0010] S2: In the electronic circuit board of the electronic current transformer, an integrator with an adaptive damping core is used to restore the primary conductor current sensing signal to the primary conductor real current, so as to eliminate the DC offset of the primary conductor current sensing signal during the integration and restoration process;

[0011] S3: Obtaining the wavelength drift of the laser light source of the current transformer according to the internal temperature of the current transformer;

[0012] S4: Based on the actual current of the primary conductor, the wavelength drift of the light source, and the total length of the current transformer transmission fiber, information entropy is introduced to optimize the laser light source modulation parameters of the current transformer optoelectronic modulator;

[0013] S5: Combine the laser light source modulation parameters to modulate the real current of the primary conductor into an optical signal;

[0014] S6: Transmit the optical signal to the current transformer demodulation module on the low-voltage side for signal restoration to obtain the primary conductor restoration current;

[0015] S7: Output the primary conductor restoration current to complete the low-loss transmission of the current transformer signal.

[0016] Second aspect

[0017] An embodiment of the present invention provides a low-loss transmission system for current transformer signals, comprising:

[0018] processor;

[0019] A memory stores computer-readable instructions, which, when executed by a processor, implement the low-loss transmission method for current transformer signals according to the first aspect.

[0020] The third aspect

[0021] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for low-loss transmission of current transformer signals according to the first aspect is implemented.

[0022] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0023] In an embodiment of the present invention, a complete closed-loop process covering signal acquisition, integral recovery, temperature compensation, modulation optimization, and signal restoration is constructed. Based on the dynamic characteristics of internal temperature and current derivatives, the laser wavelength drift is accurately obtained, and an integrator with an adaptive damping core is introduced to effectively suppress DC drift errors during the integral recovery process. Furthermore, by constructing an entropy increase rate model, fiber attenuation, temperature disturbances, and current mutations are uniformly incorporated into the modulation parameter optimization target, allowing the modulation wavelength, modulation depth, and power to be adjusted in real-time linkage, significantly reducing waveform distortion and energy loss during long-distance transmission, and improving robustness to high-frequency current disturbances and temperature drift changes. This ensures that high-fidelity, low-distortion current signal restoration can be achieved under high voltage, large current change rate, and complex external interference conditions, meeting the high-precision measurement requirements of electronic current transformers. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic flow chart of a low-loss transmission method for current transformer signals provided by an embodiment of the present invention;

[0026] Figure 2 A schematic structural diagram of an electronic current transformer provided in an embodiment of the present invention;

[0027] Figure 3 A schematic structural diagram of a low-loss transmission system for current transformer signals provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0029] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as an "exemplary" in the present invention should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of the word "exemplary" is intended to present concepts in a concrete manner. Furthermore, in the embodiments of the present invention, "and / or" can mean both or either of the two.

[0030] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0031] Reference Manual Figure 1 , shows a flow chart of a low-loss transmission method for current transformer signals provided by an embodiment of the present invention.

[0032] Reference Manual Figure 2 , shows a structural schematic diagram of an electronic current transformer provided by an embodiment of the present invention.

[0033] Figure 2 The electronic current transformer was demonstrated. It consists of a Rogowski coil on the high-voltage side, an electronic circuit board, an optoelectronic modulator assembly, a demodulation module on the low-voltage side, and an independent temperature detection module. The Rogowski coil senses the primary conductor current, performs integral reduction and optoelectronic modulation within the electronic circuit board, and then transmits the optical signal via optical fiber to the demodulation module on the low-voltage side for reduction. This structure offers strong isolation, fast response, robust anti-interference capabilities, and excellent adaptability to temperature drift.

[0034] An embodiment of the present invention provides a low-loss transmission method for a current transformer signal, which is applied to an electronic current transformer.

[0035] In a possible implementation, the electronic current transformer includes a temperature detection module, a current transformer demodulation module located on the low-voltage side, and a Rogowski coil and an electronic circuit board located on the high-voltage side.

[0036] The Rogowski coil is connected to an electronic circuit board, which is used to restore the primary conductor current sensing signal to the primary conductor real current.

[0037] The electronic circuit board includes a current transformer optoelectronic modulator integrated with a current transformer laser light source.

[0038] The temperature detection module is connected to the current transformer photoelectric modulator.

[0039] The current transformer demodulation module is connected to the current transformer photoelectric modulator through an optical fiber.

[0040] Specifically, the electronic current transformer senses changes in the primary conductor current through a Rogowski coil, outputting a voltage signal proportional to the current derivative. This is then converted back to a true current signal by an integrator on the electronic circuit board. This current signal is then converted into an optical signal by a photoelectric modulator and transmitted via optical fiber to a demodulation module on the low-voltage side for demodulation and restoration. Its advantages include high-precision conversion between electrical and optical signals, excellent insulation isolation, interference resistance, and long-distance transmission performance, making it suitable for safe and reliable current measurement in high-voltage and strong electromagnetic interference environments.

[0041] The processing flow of the low-loss transmission method of the current transformer signal may include the following steps:

[0042] S1: Obtain the internal temperature of the current transformer and the primary conductor current sensing signal on the high voltage side.

[0043] The primary conductor is the original wire that passes through the current transformer and carries the actual current on the high-voltage side. It is also the source of the measured current. It is typically the main power line of a transmission line or electrical equipment, and is the object of the current transformer's induced electrical signal. The primary conductor current induced signal is a voltage signal generated by the transformer (such as a Rogowski coil) that is proportional to the rate of change of the current in the primary conductor. This induced signal itself cannot directly represent the current magnitude and requires integration to be restored to the actual current waveform.

[0044] By synchronously collecting the primary conductor current sensing signal and the internal temperature of the current transformer, a data basis is provided for the subsequent accurate restoration of the true current waveform and correction of the wavelength drift of the laser light source, which helps to improve the overall system's response accuracy and modulation stability to interference such as temperature drift and current changes.

[0045] In a possible implementation, S1 specifically includes:

[0046] S101: Acquire the internal temperature of the current transformer through the temperature detection module.

[0047] S102: Obtain a primary conductor current sensing signal through a current transformer Rogowski coil surrounding the primary conductor.

[0048] Specifically, a Rogowski coil is wrapped around the primary conductor. When the current in the primary conductor changes, the Rogowski coil generates an induced voltage signal proportional to the current change rate based on the principle of electromagnetic induction, providing basic input for subsequent current restoration and signal modulation.

[0049] S2: In the electronic circuit board of the electronic current transformer, an integrator with an adaptive damping core is used to restore the primary conductor current sensing signal to the primary conductor real current, so as to eliminate the DC offset of the primary conductor current sensing signal during the integration and recovery process.

[0050] Among them, the adaptive damping core refers to a dynamic adjustment function core embedded in the integrator, which is used to automatically adjust the damping strength of the integral response curve according to different inductance, capacitance, resistance parameters and current change characteristics, thereby suppressing the oscillation or DC drift that may occur during the integration process and improving the integration stability and accuracy. The integrator is an integral function used to convert a voltage signal (usually a signal proportional to the rate of change of current) into a current signal. It performs a time integration operation on the input signal to restore the original current waveform. In an electronic transformer, the integrator is used to restore the voltage signal output by the Rogowski coil to a real current. The real current of the primary conductor refers to the original current signal that actually flows through the primary conductor (high-voltage conductor). It is the target current that needs to be restored by the power measurement and monitoring system. After being restored by the integrator, it is used for subsequent modulation and transmission.

[0051] It should be noted that by introducing an integrator with an adaptive damping core, high-precision restoration of the primary conductor current sensing signal can be achieved, effectively overcoming the DC drift problem existing in traditional integrators, ensuring that the restored current waveform is more realistic and stable, and significantly improving the accuracy and reliability of the transformer system under long-term operation or dynamic current disturbance conditions.

[0052] In a possible implementation, S2 specifically includes:

[0053] S201: Determine the total electromagnetic field energy function of the Rogowski coil based on the Rogowski coil equivalent circuit.

[0054] The total energy function of the electromagnetic field is specifically:

[0055]

[0056] q=∫idt

[0057] Where, E(t) represents the total energy of the electromagnetic field at time t, d represents the differential sign, L represents the inductance of the Rogowski coil equivalent circuit, and C represents the equivalent capacitance of the Rogowski coil equivalent circuit. It represents the rate of change of the primary conductor current induced signal, i.e., the current i at time t, and q represents the amount of charge stored in the equivalent capacitor of the Rogowski coil equivalent circuit.

[0058] It should be noted that the total electromagnetic field energy function is a mathematical expression used to describe the time-varying energy stored by the inductance and capacitance in the equivalent circuit of a Rogowski coil. In this model, the inductance term represents the magnetic field energy generated by the current change, and the capacitance term represents the electric field energy formed by the charge in the capacitor. The overall reflection reflects the total energy storage state of the system at a given moment and serves as the physical foundation for the subsequent construction of a dynamic integration model. By constructing a total electromagnetic field energy function based on the energy storage behavior of the inductance and capacitance, the dynamic characteristics of the Rogowski coil during the induction and response processes are fully characterized, providing a more realistic description of energy changes for integrator modeling, thereby improving the precision and accuracy of the restoration of the actual current in the primary conductor.

[0059] S202: Construct an integrator based on the total energy function of the electromagnetic field.

[0060] The calculation formula of the real current of the primary conductor obtained by the integrator is as follows:

[0061]

[0062] Among them, i(t) represents the real current of the primary conductor at time t, v in represents the induced voltage of the Rogowski coil, e represents the natural constant, sin represents the sine function, τ represents the integral time variable from 0 to time t, Represents an integrator.

[0063] Specifically, the process of deriving the integrator from the total energy of the electromagnetic field is as follows:

[0064] First, the total energy of the electromagnetic field is derived with respect to time and substituted into Faraday's law to obtain:

[0065]

[0066] Where R represents the equivalent resistance of the Rogowski coil equivalent circuit.

[0067] Then, rewrite the obtained equation into a second-order differential equation and define the integral kernel function k(t), where this integral kernel function satisfies the following formula:

[0068]

[0069] Where k(t) represents the integral kernel function at time t.

[0070] Afterwards, the formula is Laplace transformed to solve the integral kernel function k(t), thus obtaining the integrator.

[0071] It should be noted that by deriving the integral kernel function from the total electromagnetic field energy function, combining it with Faraday's law, and constructing a precise integrator, the problems of insufficient high-frequency signal response and DC drift in traditional integration methods are effectively avoided. This integrator not only has greater adaptability to dynamic current changes, but also improves the accuracy and stability of current reduction in complex electromagnetic environments, providing a more reliable raw current input for subsequent modulation and transmission.

[0072] S203: Perform parameter identification on the equivalent parameters of the Rogowski coil.

[0073] The parameter identification formula is as follows:

[0074]

[0075] Where R represents the equivalent resistance of the Rogowski coil equivalent circuit, represents the R, L, and C that make the function value take the minimum value, ‖‖ 2 Represents the square of the norm.

[0076] S204: Substitute the obtained Rogowski coil equivalent parameters into the integrator to obtain the real current of the primary conductor.

[0077] Specifically, steps S201 to S204 construct an integrator design and parameter adaptive calibration process based on the Rogowski coil equivalent circuit model. By establishing a total electromagnetic field energy function and introducing equivalent inductance, capacitance, and resistance models, the integral kernel function form is derived, and a high-precision integrator is constructed in S202. Subsequently, in S203, the minimum norm method is used to perform parameter identification to determine the true equivalent parameters R, L, and C, effectively improving the accuracy and adaptability of the integrator. Finally, in S204, the identification results are substituted into the integral calculation formula to obtain a dynamic and accurate true current waveform of the primary conductor. This method not only effectively suppresses errors caused by DC drift but also adapts to the variations in the individual characteristics of different transformers, significantly improving current reduction accuracy and the long-term stability of the system. Furthermore, for the subsequent optical modulation and long-distance transmission links, higher input signal quality improves the modulation accuracy and transmission fidelity of the entire system, improving the transmission stability of the current transformer signal and the reliability of the overall measurement link, thereby achieving low-distortion, highly robust optical signal modulation.

[0078] S3: Obtain the wavelength drift of the laser light source of the current transformer according to the internal temperature of the current transformer.

[0079] Light source wavelength drift refers to the amount by which the center wavelength of a laser's emitted light shifts relative to its nominal wavelength when affected by factors such as temperature fluctuations, current disturbances, or aging. Dynamically capturing the laser's wavelength drift provides key input for subsequent adaptive adjustment of modulation parameters, significantly improving the temperature drift stability of optical signal transmission and the overall measurement accuracy of the system.

[0080] In a possible implementation, S3 specifically includes:

[0081] The light source wavelength drift of the current transformer laser light source is determined by a pre-calibrated model or a lookup table of the current transformer laser light source.

[0082] As can be understood, by using a pre-calibrated model or lookup table for the laser light source, the corresponding wavelength drift can be quickly determined based on real-time temperature information, accurately compensating for variations in the laser's emission wavelength at different operating temperatures. This approach eliminates the need for complex real-time calculations, offers fast response times, and minimizes resource consumption, effectively improving the accuracy of modulation parameter adjustments and the stability of optical signal transmission.

[0083] S4: Based on the real current of the primary conductor, the wavelength drift of the light source and the total length of the current transformer transmission fiber, information entropy is introduced to optimize the laser light source modulation parameters of the current transformer optoelectronic modulator.

[0084] Information entropy is a core concept in information theory, used to measure the uncertainty or disorder of information in a system. In the context of optical signal transmission, information entropy can be analogized to the degree of degradation of the signal's energy or structure: higher entropy indicates a more blurred and distorted signal; lower entropy indicates a higher signal fidelity and a clearer structure. Therefore, minimizing entropy increase means preserving the original signal's information structure to the greatest extent possible, avoiding degradation caused by factors such as loss, interference, and nonlinearity.

[0085] It should be noted that by introducing the information entropy optimization mechanism, the real current of the primary conductor, the wavelength drift and the optical fiber transmission length are jointly modeled, and a response function between the laser modulation parameters and the transmission entropy increase is constructed. The modulation depth, wavelength and power are dynamically adjusted, so that the system can still maintain the stability and integrity of the optical signal under long-distance transmission and temperature changes, effectively suppressing nonlinear distortion and thus improving measurement accuracy.

[0086] In a possible implementation, the laser light source modulation parameters include modulation depth, modulation wavelength, and modulation power.

[0087] Modulation depth refers to the modulation amplitude of the laser light source's output power relative to the input current signal amplitude, which determines the degree of gain when the current signal is mapped into an optical signal. Modulation wavelength refers to the central wavelength of light emitted by the laser during the modulation process, which directly affects the light attenuation rate and nonlinear transmission characteristics in the optical fiber. Modulation power refers to the actual optical power output by the laser within a specific timeframe. By dynamically optimizing modulation depth, wavelength, and power, high-fidelity and highly adaptable conversion from current signals to optical signals can be achieved, significantly improving stability and anti-interference capabilities during long-distance transmission.

[0088] In a possible implementation, S4 specifically includes:

[0089] S401: Determine the modulation wavelength based on the actual current of the primary conductor and the wavelength drift of the light source.

[0090] The calculation formula for the modulation wavelength is:

[0091]

[0092] Where λ0 represents the initial wavelength of the light source, Δλ(T) represents the wavelength drift of the light source at temperature T, i(t) represents the real current of the primary conductor at time t, λ(t) represents the modulation wavelength at time t, and ξ represents the sensitivity coefficient of the wavelength drift of the light source to the current change rate related to the optical fiber material.

[0093] It should be noted that this model takes into account both temperature drift and transient drift caused by current mutation, so that wavelength modulation has dynamic response capability.

[0094] S402: Based on the real current of the primary conductor, the wavelength drift of the light source, and the total length of the current transformer transmission optical fiber, an entropy increase rate change function that is positively correlated with the degree of distortion of the optical transmission signal is established.

[0095] The entropy increase rate change function is specifically:

[0096]

[0097] P(t)=β(t)·i(t)

[0098] Where λ(t) represents the modulation wavelength at time t, P(t) represents the modulation power at time t, α(λ(t),T) represents the optical attenuation coefficient related to the modulation wavelength at time t and temperature T, l represents the total length of the current transformer transmission fiber, ζ represents the perturbation coefficient of the current change rate to the entropy increase rate, and S represents the energy entropy of the optical transmission signal.

[0099] The perturbation coefficient is a parameter that measures the degree of influence of the current change rate on entropy increase. It is used to quantify the contribution of rapid current perturbations (such as mutations and spikes) to the distortion or energy degradation of the optoelectronic system. The larger it is, the more sensitive the system is to the current derivative, and the modulation strategy tends to suppress the signal confusion caused by the sharp change of current. The perturbation coefficient can be set in the range of 10 -4 ~10 -2 In this model, energy entropy represents the total amount of information degradation and energy dissipated during optical signal transmission due to irreversible physical effects such as heat loss and current disturbances. It reflects the system's trend from an ordered, high-fidelity transmission state to a disordered, distorted state. This can be calculated by integrating the right side of the formula.

[0100] Specifically, represents the entropy increase of optical fiber heat dissipation, represents the entropy increase caused by current disturbance.

[0101] It is important to note that by constructing a function for the entropy increase rate based on fiber heat dissipation and current disturbances, the sources of optical signal distortion during transmission are comprehensively quantified, providing a physically interpretable evaluation metric for modulation parameter optimization. This method not only reflects the impact of fiber length, wavelength drift, and current mutations on system stability, but also enables dynamic prediction and control of signal quality under complex operating conditions, effectively improving the robustness of optoelectronic modulation systems and signal transmission fidelity.

[0102] S403: Calculate the initial modulation depth with the goal of minimizing the entropy increase rate change function value.

[0103] The entropy increase rate function represents the rate of growth of the system's information entropy (or energy entropy) per unit time. It reflects the degree of irreversible loss of optical signals during transmission due to factors such as fiber attenuation, temperature fluctuations, and current surges. A larger value indicates greater signal distortion and a greater difficulty in recovering energy or information. By integrating this function, the total entropy increase is obtained, which serves as the objective function for modulation parameter optimization.

[0104] The specific solution formula is:

[0105]

[0106] in, Represents taking the function The initial modulation depth β(t) at time t when the minimum value is taken, and t0 represents the preset modulation duration window.

[0107] It should be noted that those skilled in the art can set the size of the preset modulation duration window according to actual needs, and the present invention does not limit this.

[0108] It should be noted that by optimizing the entropy increase rate function to minimize the change in the initial modulation depth, the modulator produces minimal information loss and distortion during subsequent optical signal transmission. This method can adaptively adjust the modulation intensity based on actual current fluctuations and fiber transmission conditions, improving the precision and dynamic adaptability of the modulation strategy and effectively ensuring the fidelity and stability of signal transmission under complex operating conditions.

[0109] S404: Determine an upper limit of the modulation depth according to the Heisenberg uncertainty principle.

[0110] The Heisenberg uncertainty principle describes the unbreakable measurement precision limits between a particle's position and momentum (or energy and time). In this scheme, it's used to set the energy-time limit for the modulation system: the maximum modulatable power (or depth) per unit time cannot exceed the physical limits of photon energy and transmission capacity, thus providing a safety margin.

[0111] The calculation formula for the upper limit of modulation depth is as follows:

[0112]

[0113] Among them, β max (t) represents the upper limit of the modulation depth at time t, h represents Planck's constant, c represents the speed of light, and Z fiber It represents the equivalent impedance related to the optical fiber material, which describes the transmission of light in the optical fiber, namely the optical fiber wave impedance, and e represents the elementary charge.

[0114] It should be noted that by introducing the Heisenberg uncertainty principle to set a physical upper limit for the modulation depth, it is ensured that the laser power during the modulation process will not exceed the energy range that the system can carry, thereby effectively preventing problems such as modulator overload, laser damage or signal distortion, and improving the stability and safety of the system under strong disturbance conditions.

[0115] S405: When the initial modulation depth is greater than the upper limit of the modulation depth, the initial modulation depth is truncated by the upper limit of the modulation depth to obtain the target modulation depth; otherwise, the initial modulation depth is output as the target modulation depth.

[0116] S406: Determine the modulation power based on the target modulation depth and the actual current of the primary conductor.

[0117] S407: Output the modulation wavelength, target modulation depth and modulation power to complete the optimization of the laser light source modulation parameters.

[0118] Specifically, by jointly modeling the actual current in the primary conductor, the laser wavelength drift caused by temperature, and the fiber transmission length, an optimization mechanism based on information entropy minimization is introduced to dynamically calculate the modulation wavelength, modulation depth, and modulation power. The entropy increase rate function quantifies the impact of heat dissipation and current disturbances on signal distortion and serves as the objective function for modulation depth optimization. A physical upper limit for the modulation depth is set in conjunction with the Heisenberg uncertainty principle to ensure that the modulation intensity does not exceed the system's carrying capacity. Finally, closed-loop optimization of the modulation parameters is achieved through truncation and parameter adjustment. This process significantly improves the adaptability and safety of the modulation, reduces nonlinear losses and signal distortion during fiber transmission, and enhances the system's measurement stability and fidelity in scenarios with complex current fluctuations and temperature changes.

[0119] S5: Combined with the laser light source modulation parameters, the real current of the primary conductor is modulated into an optical signal.

[0120] It should be noted that applying the optimized laser light source modulation parameters (including modulation wavelength, modulation depth, and modulation power) to the optoelectronic modulator allows the primary conductor's real current to be converted into a corresponding optical signal with high precision. This process achieves an orderly mapping of electrical signals to optical signals, which helps ensure signal fidelity and energy consistency during subsequent transmission and reduces modulation loss and distortion caused by parameter mismatch.

[0121] In a possible implementation, S5 specifically includes:

[0122] S501: Initialize the current transformer optoelectronic modulator according to the laser light source modulation parameters.

[0123] S502: Using the initialized current transformer optoelectronic modulator, modulate the real current of the primary conductor into an optical signal.

[0124] It can be understood that by initializing the optoelectronic modulator according to the optimized laser light source modulation parameters, its modulation behavior is more in line with the current current and environmental conditions, achieving accurate optical signal mapping of the real current of the primary conductor, and significantly improving the matching degree of the modulation process and the signal conversion accuracy.

[0125] S6: The optical signal is transmitted to the current transformer demodulation module on the low-voltage side for signal restoration to obtain the primary conductor restoration current.

[0126] It should be noted that the modulated optical signal on the high-voltage side is transmitted via optical fiber to the demodulation module on the low-voltage side, where a photoelectric demodulation circuit converts the optical signal into an electrical signal corresponding to the original primary conductor's true current. This process enables long-distance, isolated signal transmission and accurate demodulation, providing excellent resistance to electromagnetic interference and significantly improving the safety and accuracy of the measurement system in high-voltage, high-noise environments.

[0127] S7: Output the primary conductor restoration current to complete the low-loss transmission of the current transformer signal.

[0128] In practical applications, the entire solution constitutes a complete closed-loop process for low-loss electronic current transformer signal transmission, encompassing everything from high-voltage side current sensing and temperature acquisition, integral depolarization to recover the true current, dynamic acquisition of laser wavelength drift, information entropy-based modulation parameter optimization, optical signal modulation, long-distance transmission, and low-voltage side signal demodulation and restoration. By introducing an adaptive integrator and information entropy minimization mechanism, this method effectively compensates for temperature drift, current mutations, and transmission losses. This significantly improves the system's modulation accuracy, transmission fidelity, and anti-interference capabilities under complex operating conditions, meeting the high-reliability measurement requirements of electronic current transformers in high-voltage, high-disturbance scenarios.

[0129] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0130] In an embodiment of the present invention, a complete closed-loop process covering signal acquisition, integral recovery, temperature compensation, modulation optimization, and signal restoration is constructed. Based on the dynamic characteristics of internal temperature and current derivatives, the laser wavelength drift is accurately obtained, and an integrator with an adaptive damping core is introduced to effectively suppress DC drift errors during the integral recovery process. Furthermore, by constructing an entropy increase rate model, fiber attenuation, temperature disturbances, and current mutations are uniformly incorporated into the modulation parameter optimization target, allowing the modulation wavelength, modulation depth, and power to be adjusted in real-time linkage, significantly reducing waveform distortion and energy loss during long-distance transmission, and improving robustness to high-frequency current disturbances and temperature drift changes. This ensures that high-fidelity, low-distortion current signal restoration can be achieved under high voltage, large current change rate, and complex external interference conditions, meeting the high-precision measurement requirements of electronic current transformers.

[0131] Reference Manual Figure 3 , showing a structural schematic diagram of a low-loss transmission system for current transformer signals provided by the present invention.

[0132] The present invention further provides a low-loss transmission system 20 for current transformer signals, which is applied to the above-mentioned low-loss transmission method for current transformer signals, comprising:

[0133] Processor 201.

[0134] The memory 202 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 201 , the low-loss transmission method for the current transformer signal of the method embodiment is implemented.

[0135] The low-loss transmission system 20 for current transformer signals provided by the present invention can execute the above-mentioned low-loss transmission method for current transformer signals and achieve the same or similar technical effects. To avoid repetition, the present invention will not elaborate on them.

[0136] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0137] In an embodiment of the present invention, a complete closed-loop process covering signal acquisition, integral recovery, temperature compensation, modulation optimization, and signal restoration is constructed. Based on the dynamic characteristics of internal temperature and current derivatives, the laser wavelength drift is accurately obtained, and an integrator with an adaptive damping core is introduced to effectively suppress DC drift errors during the integral recovery process. Furthermore, by constructing an entropy increase rate model, fiber attenuation, temperature disturbances, and current mutations are uniformly incorporated into the modulation parameter optimization target, allowing the modulation wavelength, modulation depth, and power to be adjusted in real-time linkage, significantly reducing waveform distortion and energy loss during long-distance transmission, and improving robustness to high-frequency current disturbances and temperature drift changes. This ensures that high-fidelity, low-distortion current signal restoration can be achieved under high voltage, large current change rate, and complex external interference conditions, meeting the high-precision measurement requirements of electronic current transformers.

[0138] It should be understood that the processor in the embodiments of the present invention may be a central processing unit (CPU), but may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0139] It should also be understood that the memory in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0140] The above embodiments can be implemented in whole or in part through software, hardware (such as circuits), firmware, or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. A computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, the process or function according to the embodiments of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired method (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains a collection of one or more available media. The available media can be magnetic media (such as floppy disks, hard disks, tapes), optical media (such as DVDs), or semiconductor media. The semiconductor media can be a solid-state drive.

[0141] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. A and B can be singular or plural. Furthermore, the character " / " as used herein generally indicates an "or" relationship between the associated objects, but it may also indicate an "and / or" relationship. For specific understanding, please refer to the context.

[0142] In this disclosure, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or plural.

[0143] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0144] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0145] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described equipment, devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0146] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, and can be electrical, mechanical, or other forms.

[0147] Units described as separate components may or may not be physically separate, and 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 these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0148] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0149] If the function is implemented in the form of 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, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, and other media that can store program codes.

[0150] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for low-loss transmission of current transformer signals as described in the method embodiment is implemented.

[0151] The computer-readable storage medium provided by the present invention can implement the steps and effects of the low-loss transmission method of the current transformer signal of the above method embodiment. To avoid repetition, the present invention will not elaborate on them.

[0152] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0153] In an embodiment of the present invention, a complete closed-loop process covering signal acquisition, integral recovery, temperature compensation, modulation optimization, and signal restoration is constructed. Based on the dynamic characteristics of internal temperature and current derivatives, the laser wavelength drift is accurately obtained, and an integrator with an adaptive damping core is introduced to effectively suppress DC drift errors during the integral recovery process. Furthermore, by constructing an entropy increase rate model, fiber attenuation, temperature disturbances, and current mutations are uniformly incorporated into the modulation parameter optimization target, allowing the modulation wavelength, modulation depth, and power to be adjusted in real-time linkage, significantly reducing waveform distortion and energy loss during long-distance transmission, and improving robustness to high-frequency current disturbances and temperature drift changes. This ensures that high-fidelity, low-distortion current signal restoration can be achieved under high voltage, large current change rate, and complex external interference conditions, meeting the high-precision measurement requirements of electronic current transformers.

[0154] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

[0155] There are a few points to note:

[0156] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0157] (2) For the sake of clarity, the thickness of layers or regions in the drawings used to describe the embodiments of the present invention are exaggerated or reduced, that is, these drawings are not drawn to scale. It is understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or intervening elements may be present.

[0158] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to form new embodiments.

[0159] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A low-loss transmission method for current transformer signals, characterized in that: Applied to electronic current transformers; the method includes: S1: Obtain the internal temperature of the current transformer and the primary conductor current sensing signal on the high voltage side; S2: In the electronic circuit board of the electronic current transformer, using an integrator with an adaptive damping core to restore the primary conductor current sensing signal to the primary conductor real current, so as to eliminate the DC offset of the primary conductor current sensing signal during the integration and restoration process; S3: Obtaining a wavelength drift of a laser light source of the current transformer according to an internal temperature of the current transformer; S4: combining the real current of the primary conductor, the wavelength drift of the light source, and the total length of the current transformer transmission optical fiber, introducing information entropy to optimize the laser light source modulation parameters of the current transformer optoelectronic modulator; S5: Modulating the real current of the primary conductor into an optical signal in combination with the modulation parameters of the laser light source; S6: Transmitting the optical signal to a current transformer demodulation module on the low-voltage side for signal restoration to obtain a primary conductor restoration current; S7: Outputting the primary conductor restoration current to complete the low-loss transmission of the current transformer signal.

2. The low-loss transmission method for current transformer signals according to claim 1, characterized in that: The electronic current transformer includes a temperature detection module, a current transformer demodulation module located on the low-voltage side, and a Rogowski coil and an electronic circuit board located on the high-voltage side; The Rogowski coil is connected to the electronic circuit board, and the electronic circuit board is used to restore the primary conductor current sensing signal to the primary conductor real current; The electronic circuit board includes a current transformer photoelectric modulator integrated with a current transformer laser light source; The temperature detection module is connected to the current transformer photoelectric modulator; The current transformer demodulation module is connected to the current transformer photoelectric modulator via an optical fiber.

3. The low-loss transmission method for current transformer signals according to claim 2, characterized in that: Said S1 specifically includes: S101: Acquire the internal temperature of the current transformer through the temperature detection module; S102: Acquire the primary conductor current sensing signal through a current transformer Rogowski coil surrounding the primary conductor.

4. The low-loss transmission method for current transformer signals according to claim 2, characterized in that: The S2 specifically includes: S201: Determine a total electromagnetic field energy function of the Rogowski coil based on an equivalent circuit of the Rogowski coil; S202: constructing the integrator based on the total electromagnetic field energy function; S203: performing parameter identification on equivalent parameters of the Rogowski coil; S204: Substitute the obtained Rogowski coil equivalent parameters into the integrator to obtain the real current of the primary conductor.

5. The low-loss transmission method for current transformer signals according to claim 1, characterized in that: The S3 is specifically: The light source wavelength drift of the current transformer laser light source is determined by a pre-calibrated model or a lookup table of the current transformer laser light source.

6. The low-loss transmission method for current transformer signals according to claim 1, characterized in that: The laser light source modulation parameters include modulation depth, modulation wavelength and modulation power.

7. The low-loss transmission method for current transformer signals according to claim 6, characterized in that: The S4 specifically includes: S401: Determine the modulation wavelength based on the real current of the primary conductor and the wavelength drift of the light source; S402: Establishing an entropy increase rate change function that is positively correlated with the degree of optical transmission signal distortion based on the actual current of the primary conductor, the wavelength drift of the light source, and the total length of the current transformer transmission optical fiber; S403: solving the initial modulation depth with the goal of minimizing the entropy increase rate change function value; S404: Determine the upper limit of the modulation depth according to the Heisenberg uncertainty principle; S405: If the initial modulation depth is greater than the modulation depth upper limit, truncate the initial modulation depth by the modulation depth upper limit to obtain a target modulation depth; otherwise, output the initial modulation depth as the target modulation depth; S406: Determine the modulation power based on the target modulation depth and the actual current of the primary conductor; S407: Output the modulation wavelength, the target modulation depth, and the modulation power to complete the optimization of the laser light source modulation parameters.

8. The low-loss transmission method for current transformer signals according to claim 1, characterized in that: The S5 specifically includes: S501: Initializing the current transformer optoelectronic modulator according to the laser light source modulation parameters; S502: Utilize the initialized current transformer optoelectronic modulator to modulate the real current of the primary conductor into the optical signal.

9. A low-loss transmission system for current transformer signals, characterized in that: include: processor; A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are executed by the processor, the low-loss transmission method for current transformer signals according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the low-loss transmission method for current transformer signals according to any one of claims 1 to 8 is implemented.

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