Extra-high voltage field lightweight calibration system and method based on capacitor energy storage and power amplification

Abstract

The invention discloses an extra-high voltage field lightweight calibration system and method based on capacitor energy storage and power amplification. The system comprises a charging module, a power supply module, a power amplifier module and a novel calibrator, the charging module is used for charging the power supply module, the power supply module is used for providing energy signals for the power amplifier module, and the power amplifier module is connected with a standard device and a calibrated test object to form a test loop. The novel calibrator is respectively connected with the charging module, the power supply module and the power amplifier module, and is used for performing parameter control on the test process.

Description

Technical Field

[0001] This invention relates to the field of high voltage and high current measurement technology, and more specifically, to an ultra-high voltage field lightweight calibration system and method based on capacitor energy storage and power amplification. Background Technology

[0002] As the "sensory nerves" of the power grid, the accuracy of primary measuring equipment such as current transformers (CTs) and voltage transformers (VTs) directly affects the correctness of relay protection operations, the fairness of electricity metering, and the accurate perception of system status. Therefore, periodic calibration of primary measuring equipment at UHV sites is a mandatory technical procedure to ensure the safe and economical operation of the power grid.

[0003] Currently, UHV (Ultra-High Voltage) field calibration work both domestically and internationally primarily relies on traditional power frequency current boost (voltage boost) source systems. The core working principle of this system is to use a large-capacity voltage regulator (or frequency converter) to drive an extremely bulky power frequency current booster (for current calibration) or resonant voltage booster (for voltage calibration). These devices are based on the principle of electromagnetic induction, increasing the current or voltage by changing the turns ratio, ultimately generating the required thousands of amperes of power frequency current or hundreds of kilovolts of power frequency high voltage on the primary side of the sensor under calibration. Although this method is technically mature and widely used, its inherent limitations have increasingly become a bottleneck restricting the efficiency of UHV operation and maintenance and technological development. 1. The equipment system is extremely bulky, making movement and deployment difficult: To generate megawatt-level power at the industrial frequency, the core and windings of the current booster (voltage booster) are enormous. A single current booster generating 5000A can weigh over 3 tons, requiring an equally bulky voltage regulator and power supply vehicle. This necessitates not only heavy-duty truck transportation but also the use of cranes and other machinery within the substation for handling and positioning, placing extremely high demands on on-site transportation roads, installation space, and foundation bearing capacity. In complex terrain and limited space environments such as the Qinghai-Tibet Plateau, mountainous areas, and hydropower stations, the equipment is often difficult to access or takes an extremely long time to deploy, severely impacting the efficiency and feasibility of calibration operations.

[0004] 2. High energy consumption and demanding on-site power conditions: Traditional methods require drawing enormous apparent power (hundreds of kVA to several MVA) from the grid during calibration. However, many UHV substations, newly built stations, or expansion stations may not have sufficient backup power available during the initial commissioning phase. Therefore, teams often need to carry their own high-power diesel generators, which not only incurs high fuel costs, noise and exhaust pollution, but also increases the complexity and cost of operation and maintenance.

[0005] 3. Limited Output Waveform, High Harmonic Content, and Functional Limitations: Traditional power frequency current boosters are essentially highly inductive devices, resulting in poor-quality output current waveforms and typically high total harmonic distortion (THD). This makes it difficult to generate pure sine waves and even more impossible to simulate complex operating conditions such as high-order harmonics and transient inrush currents actually present in the power grid. Consequently, they cannot accurately calibrate the frequency characteristics of increasingly widely used broadband sensors or harmonic measurement devices; their functionality is limited to basic power frequency calibration, failing to meet the growing demand for multi-dimensional measurement data from smart grids.

[0006] 4. Low level of automation, poor data traceability and consistency: Traditional calibration processes heavily rely on the experience and responsibility of operators. From equipment wiring and current / voltage control to manual data recording and error calculation, the entire process is cumbersome and prone to human error. Calibrations performed by different teams at different times may result in significant fluctuations in data quality and reliability, hindering long-term equipment status trend analysis and accurate lifecycle management.

[0007] To alleviate some of the aforementioned problems, the industry has explored various technologies. For example, "capacitor compensation" boost technology is used. By connecting compensation capacitors in series and parallel in the field test circuit, the circuit operates near parallel resonance, thereby outputting high voltage and high current while reducing power supply capacity requirements. While this method reduces the power supply size to some extent, it does not fundamentally change the system's large and cumbersome nature. This is because the resonant capacitor itself is also a large-capacity device, and the system's tuning and stabilization are complex, with limited flexibility in output waveform and frequency. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides a lightweight on-site calibration system and method for ultra-high voltage power transmission based on capacitor energy storage and power amplification.

[0009] According to one aspect of the present invention, a lightweight on-site calibration system for ultra-high voltage power transmission based on capacitor energy storage and power amplification is provided, comprising: a charging module, a power supply module, a power amplifier module, and a novel calibration instrument, wherein... The charging module is used to charge the power module, the power module is used to provide energy signals to the power amplifier module, the power amplifier module is connected to the standard device and the test sample to form a test circuit, and the new calibrator is connected to the charging module, the power module and the power amplifier module respectively to control the parameters of the test process.

[0010] Optionally, it also includes a protection module, which is connected to the protection control unit of the new calibrator to realize the system's self-test and security verification.

[0011] Optionally, the charging module includes a charging interface and a first charging control unit. The first charging control unit is used to connect to the second charging control unit of the new calibrator, receive charging commands, and charge the power module through the charging interface.

[0012] Optionally, the power module includes a supercapacitor bank and a power control unit, which controls the supercapacitor bank to release energy to the power amplifier module.

[0013] Optionally, the two supercapacitors in the supercapacitor bank adopt a symmetrical structure, have the same capacity and rated voltage, and are charged through independent charging management circuits.

[0014] Optionally, the power amplifier module includes a power amplifier group and a signal conditioning unit. The signal conditioning unit is used to receive instructions from the test control unit in the new calibrator to generate a preset high-precision standard waveform signal as the driving source of the power amplifier group.

[0015] Optionally, the new calibrator also includes: Impedance testing unit is used to perform preliminary measurement of loop impedance before testing, providing a load matching reference for the system; The display unit is used for status monitoring, parameter setting, and result display to confirm the system status. The secondary measurement unit is used to synchronously acquire the output signals of the standard device and the test sample at a high sampling rate through its high-precision acquisition card, and to calculate the error parameters of the test sample at the current test point in real time using the built-in algorithm.

[0016] According to another aspect of the present invention, a lightweight on-site calibration method for ultra-high voltage power transmission based on capacitor energy storage and power amplification is provided, comprising: Step 1: Use the protection control module to perform system self-testing and participate in charge discharge; Step 2: Charge the supercapacitor bank in the power module through the charging module; Step 3: After the supercapacitor bank is fully charged, the supercapacitor bank is used to power the power amplifier module. The power amplifier module is controlled by a new type of calibrator to generate a high-precision standard waveform signal, and a safety verification is performed by the protection control module. Step 4: After the verification is passed, the standard waveform signal is amplified by the power amplifier group and output to the test circuit with a high-precision high current of set waveform and amplitude. Step 5: The output signals of the standard device and the test sample in the test circuit are collected synchronously by the new calibrator, and the error parameters of the test sample at the current test point are calculated in real time using the built-in algorithm; Step 6: Automatically step the output voltage to the next test point according to the preset sequence and repeat the measurement process of steps 1-5; Step 7: After all test points have been tested, generate a calibration report.

[0017] Optionally, step 3 also includes: real-time monitoring of the voltage of the supercapacitor bank and the power amplifier output waveform, and dynamic adjustment of the amplitude of the high-precision standard waveform signal.

[0018] Optionally, an intelligent equalization charging strategy is adopted during the charging process in step 2 to ensure that the voltage consistency error between the two sets of supercapacitors in the supercapacitor bank is less than a preset value.

[0019] According to another aspect of the present invention, a computer-readable storage medium is provided, the storage medium storing a computer program for performing the methods described in any of the above aspects of the present invention.

[0020] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: a processor; a memory for storing executable instructions of the processor; the processor being configured to read the executable instructions from the memory and execute the instructions to implement the method described in any of the preceding aspects of the present invention.

[0021] Therefore, . Attached Figure Description

[0022] Exemplary embodiments of the present invention can be more fully understood by referring to the following figures: Figure 1 This is a schematic diagram of the structure of a lightweight on-site calibration system for ultra-high voltage power transmission based on capacitor energy storage and power amplification, provided by an exemplary embodiment of the present invention. Figure 2 This is a flowchart illustrating an exemplary embodiment of the present invention for a lightweight on-site calibration method for ultra-high voltage power transmission based on capacitor energy storage and power amplification. Detailed Implementation

[0024] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein.

[0025] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0026] Those skilled in the art will understand that the terms "first," "second," etc., in the embodiments of the present invention are only used to distinguish different steps, devices, or modules, and do not represent any specific technical meaning, nor do they indicate a necessary logical order between them.

[0027] It should also be understood that in the embodiments of the present invention, "multiple" can refer to two or more, and "at least one" can refer to one, two or more.

[0028] It should also be understood that any component, data or structure mentioned in the embodiments of the present invention can generally be understood as one or more unless explicitly defined or given contrary instructions in the context.

[0029] Furthermore, the term "and / or" in this invention is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this invention generally indicates that the preceding and following related objects have an "or" relationship.

[0030] It should also be understood that the description of the various embodiments in this invention emphasizes the differences between the various embodiments, and the similarities or similarities can be referred to each other. For the sake of brevity, they will not be described in detail.

[0031] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0032] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0033] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0034] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0035] Figure 1 This is a schematic diagram of the structure of a lightweight on-site calibration system for ultra-high voltage power transmission based on capacitor energy storage and power amplification, provided by an exemplary embodiment of the present invention. Figure 1 As shown, the ultra-high voltage field lightweight calibration system based on capacitor energy storage and power amplification includes: a charging module, a power supply module, a power amplifier module, and a novel calibration instrument. The charging module is used to charge the power module, the power module is used to provide energy signals to the power amplifier module, the power amplifier module is connected to the standard device and the test sample to form a test circuit, and the new calibrator is connected to the charging module, the power module and the power amplifier module respectively to control the parameters of the test process.

[0036] Specifically, to address the core challenges of bulky equipment, high energy consumption, monotonous waveforms, and low automation in UHV (ultra-high voltage) field calibration, this invention provides an integrated lightweight calibration system and method based on supercapacitor energy storage and precision power amplification. This system, through the integration of high-energy-density energy storage, high-precision signal generation, and high-power amplification technologies, fundamentally transforms calibration equipment from "fixed heavy equipment" to "mobile precision instruments." This method not only achieves precise output of thousands of amperes of power frequency current with extremely low energy consumption and unprecedented portability, but also flexibly generates pure sine waves, high-order harmonic composite waves, and transient waveforms, fully meeting the high-standard calibration requirements of broadband sensors and harmonic measurement devices. This invention provides a disruptive technological means for rapid, efficient, and intelligent operation and maintenance at UHV transmission sites, significantly improving the feasibility, safety, and data quality of calibration operations, and playing a crucial role in ensuring the safe and reliable operation of future new power systems.

[0037] This invention provides a lightweight on-site calibration system for ultra-high voltage (UHV) power grids based on capacitor energy storage and power amplification. It addresses the prominent problems of existing calibration technologies, such as reliance on bulky power frequency current boosting devices, huge on-site energy consumption, single output waveform, and inability to simulate complex operating conditions. The system can achieve high-precision, multi-waveform high current and high voltage output in an integrated and portable manner, significantly improving the efficiency, adaptability, and data reliability of UHV on-site calibration. It provides advanced technical means for the accurate measurement and condition assessment of primary equipment in smart grids.

[0038] Optionally, it also includes a protection module, which is connected to the protection control unit of the new calibrator to realize the system's self-test and security verification.

[0039] Optionally, the charging module includes a charging interface and a first charging control unit. The first charging control unit is used to connect to the second charging control unit of the new calibrator, receive charging commands, and charge the power module through the charging interface.

[0040] Optionally, the power module includes a supercapacitor bank and a power control unit, which controls the supercapacitor bank to release energy to the power amplifier module.

[0041] Optionally, the two supercapacitors in the supercapacitor bank adopt a symmetrical structure, have the same capacity and rated voltage, and are charged through independent charging management circuits.

[0042] Optionally, the power amplifier module includes a power amplifier group and a signal conditioning unit. The signal conditioning unit is used to receive instructions from the test control unit in the new calibrator to generate a preset high-precision standard waveform signal as the driving source of the power amplifier group.

[0043] Optionally, the new calibrator also includes: Impedance testing unit is used to perform preliminary measurement of loop impedance before testing, providing a load matching reference for the system; The display unit is used for status monitoring, parameter setting, and result display to confirm the system status. The secondary measurement unit is used to synchronously acquire the output signals of the standard device and the test sample at a high sampling rate through its high-precision acquisition card, and to calculate the error parameters of the test sample at the current test point in real time using the built-in algorithm.

[0044] According to another embodiment of the present invention, the ultra-high voltage field lightweight calibration method based on capacitor energy storage and power amplification includes: Step 1: Use the protection control module to perform system self-testing and participate in charge discharge; Step 2: Charge the supercapacitor bank in the power module through the charging module; Step 3: After the supercapacitor bank is fully charged, the supercapacitor bank is used to power the power amplifier module. The power amplifier module is controlled by a new type of calibrator to generate a high-precision standard waveform signal, and a safety verification is performed by the protection control module. Step 4: After the verification is passed, the standard waveform signal is amplified by the power amplifier group and output to the test circuit with a high-precision high current of set waveform and amplitude. Step 5: The output signals of the standard device and the test sample in the test circuit are collected synchronously by the new calibrator, and the error parameters of the test sample at the current test point are calculated in real time using the built-in algorithm; Step 6: Automatically step the output voltage to the next test point according to the preset sequence and repeat the measurement process of steps 1-5; Step 7: After all test points have been tested, generate a calibration report.

[0045] Specifically, refer to Figure 2 As shown, the ultra-high voltage field lightweight calibration method based on capacitor energy storage and power amplification includes the following steps: Step S1: On-site Deployment and System Power-On. Transport the integrated calibration system to the UHV on-site calibration point and connect it to the local mains power or a small generator. Power on the new calibrator; its display module provides a fully Chinese graphical user interface for status monitoring, parameter setting, and result display, confirming the system status.

[0046] Step S2: Wiring and Parameter Preset. Disconnect the external power supply and connect the high-power output terminal of the power amplifier (amplifier group) in series with the primary winding loop of the device under test (such as a current transformer); also install standard devices (such as standard Rogowski coils, shunts) in the same loop. Use the test control module of the new calibrator to set the waveform type, target current value, test duration, and other parameters required for calibration. The impedance measurement module can perform a preliminary measurement of the loop impedance before testing, providing a load matching reference for the system.

[0047] Step S3: System Self-Test and Residual Charge Discharge. After wiring and parameter settings are completed, the system self-test program is started. The protection control module will lead this process, automatically checking the communication status of each unit and the safety interlock devices. At the same time, the test control module will instruct the power amplifier to output a brief low-amplitude zero-point signal to discharge any residual charge that may exist in the circuit or eliminate electromagnetic interference. The self-test results and progress will be displayed on the display module in real time.

[0048] Step S4: Supercapacitor Bank Charging. After passing the self-test, reconnect the external power supply. The operator initiates the charging process through the charging control module. This module intelligently controls the charging module to independently and evenly charge the positive and negative supercapacitors using the optimal curve, and monitors voltage and current throughout the process. The protection control module monitors simultaneously to ensure charging safety. Charging status and progress are displayed on the interface in real time.

[0049] Step S5: High-precision signal generation and power amplification preparation. After charging is complete, the system automatically disconnects the external power supply again, switching to full power supply from the supercapacitor. After final wiring confirmation, the test control module instructs the signal conditioning unit to generate a preset high-precision standard waveform signal as the drive source for the power amplifier. The protection control module performs a final safety check again to confirm that the system is in standby mode.

[0050] Step S6: Energy Release and High-Precision High-Current Output. Once everything is ready, start the output via the test control module or physical switch. The power control unit controls the supercapacitor bank to release energy, the power amplifier amplifies the signal with high fidelity, and outputs a high-precision high-current with the set waveform and amplitude to the test circuit. The protection control module monitors this process in real time to ensure output safety.

[0051] Step S7: Synchronous Data Acquisition and Error Calculation. During the calibration current stabilization output process, the secondary measurement module starts working, synchronously acquiring the output signals of the standard device and the test sample at a high sampling rate through its high-precision acquisition card, and using the built-in algorithm to calculate error parameters such as the ratio difference and phase difference of the test sample at the current test point in real time.

[0052] Step S8: Automatic Step and Multi-Point Testing. After the current test point is completed, the test control module will automatically step the output current to the next test point according to the preset sequence, and repeat the output and measurement process of steps S6 and S7 until the calibration test of all preset points is completed. The entire process requires no manual intervention. During the test, an automatic step method is used to automatically switch between different current test points and automatically complete the data acquisition, error calculation and report generation for all test points.

[0053] Step S9: Result Determination and Report Generation. After all tests are completed, the test control module will automatically call the algorithm to make a final determination on the error data of all test points and generate a complete calibration report, including calibration curves, error tables, etc. The final report will be displayed on the display module and can be exported or printed, completing all calibration work.

[0054] By adopting the above technical solution, the instantaneous high-power discharge characteristics of supercapacitors and high-performance power amplification technology are utilized to replace the traditional bulky power frequency booster. This enables the rapid and accurate output of high-quality high-current test signals on-site without the need for large power supply vehicles, completely solving the inherent drawbacks of traditional methods such as heavy equipment, high energy consumption, and monotonous waveforms. Furthermore, by using two sets of supercapacitors to provide energy for the positive and negative half-waves of the power amplifier respectively, the voltage stress and ripple requirements of a single set of capacitors are significantly reduced, improving energy utilization efficiency and output waveform quality.

[0055] The present invention is further configured such that the two sets of supercapacitors adopt a symmetrical architecture, have the same capacity and rated voltage, and are charged through independent charging management circuits.

[0056] By adopting the above technical solution, the energy supply balance of the positive and negative half-waves can be ensured, the DC component and asymmetric distortion of the output waveform can be reduced, and the calibration accuracy can be improved.

[0057] The present invention is further configured such that: the power amplifier adopts a bridge output structure, and the positive and negative half-waves are amplified by two independent power modules respectively.

[0058] By adopting the above technical solutions, the reliability and output capability of the system can be further improved. The failure of a single power module will not lead to the complete failure of the system, and it is also convenient for modular design and maintenance.

[0059] The present invention is further configured such that: in step S6, the test control module monitors the voltage of the supercapacitor and the output waveform of the power amplifier in real time, and dynamically adjusts the output amplitude of the signal generator.

[0060] By adopting the above technical solution, the voltage drop caused by capacitor discharge can be compensated, the stability of the output current can be maintained, and the output accuracy can be ensured to meet the requirements throughout the test process.

[0061] The present invention is further configured such that: during the charging process in step S4, the system employs an intelligent equalization charging strategy to ensure that the voltage consistency error between the two sets of supercapacitors is less than 0.5%, thereby guaranteeing the symmetry and stability of the output waveform.

[0062] By adopting the above technical solution, the symmetry of the positive and negative half-wave outputs can be maximized, waveform distortion can be reduced, measurement accuracy can be improved, and the service life of the supercapacitor can be extended. Simultaneously, while ensuring the safety of the supercapacitor and preventing overcharging, the available capacity of the on-site power supply can be utilized to the maximum extent, reducing charging time to less than 15 minutes, greatly improving on-site operational efficiency.

[0063] This invention discloses a lightweight on-site calibration system and method for ultra-high voltage power transmission based on capacitor energy storage and power amplification, which achieves the following advantages compared with existing technologies: (1) Using supercapacitors as the core energy storage components and combining them with high-frequency power amplification technology, the traditional bulky power frequency booster and power vehicle are completely replaced, and the entire system is integrated into a portable chassis, reducing the weight by more than 90%, which greatly reduces the difficulty of transportation and on-site deployment. It is especially suitable for UHV substations in complex terrain environments such as mountainous areas and plateaus.

[0064] (2) The system has extremely low energy consumption. It only needs to use ordinary mains power on site for a short time to complete all tests. The average power consumption is less than one-tenth of that of traditional methods. It does not need to rely on large-capacity power access points or diesel generators, which significantly reduces operating costs and environmental impact.

[0065] (3) Based on the output architecture of high-precision signal generator and high-performance power amplifier, it can generate pure power frequency sine waves with total harmonic distortion of less than 0.5%, and can flexibly output composite waveforms and transient waveforms containing specified harmonics, breaking through the limitations of poor waveform quality and single function of traditional methods, and meeting the comprehensive calibration needs of new devices such as broadband sensors and smart energy meters.

[0066] (4) The entire testing process, including output control, data acquisition, error calculation and report generation, is automatically completed by the main control unit, realizing "one-click" operation, completely eliminating the tediousness and subjective error of manual operation, and greatly improving the efficiency, consistency and data reliability of calibration work.

[0067] (5) The dual supercapacitor architecture with independent power supply for positive and negative half-waves and intelligent closed-loop control strategy effectively ensures the waveform symmetry and stability of the output current in a large dynamic range. Its uncertainty is better than 1×10-3, and the calibration accuracy and reliability reach or even exceed the level of traditional large fixed equipment.

[0068] (6) The system has multiple built-in electrical protection and status monitoring mechanisms, and the energy is stored in the supercapacitor instead of being drawn directly from the power grid. In case of abnormality, it can be cut off in milliseconds, and the energy is controllable, which greatly improves the safety of field tests.

[0069] In one embodiment, the calibration target is a 200:1 current transformer used in ultra-high voltage direct current (UHVDC) transmission projects, with a rated primary current of 100A. The main equipment parameters selected in this embodiment are as follows: The supercapacitor energy storage module consists of two symmetrical supercapacitor banks, with both the positive bank (C+) and the negative bank (C-) having a nominal capacity of 500F and a rated voltage of 16.2V. Each bank is equipped with an independent intelligent charging management unit. The power amplifier module has a maximum output current of 125A, a peak output power of 2kW, and a bandwidth of 0-10kHz. The high-precision signal generator can output arbitrary waveforms up to 10kHz, and its amplitude, frequency, and phase can be controlled by programming through the main control unit. The standard reference sensor is a 0.05-class precision current transformer, whose output is connected to the high-precision acquisition card of the main control unit, with a sampling rate of 100kS / s.

[0070] The specific calibration steps are as follows: First, transport the system to the UHV converter station site. Use the local power supply, converted to DC by the intelligent charging management unit, to charge the supercapacitor bank. After approximately 15 minutes, both capacitor banks will reach their rated operating voltage of 16.2V. After charging is complete, disconnect the external power supply. Connect the output of the power amplifier in series with the primary side of the current transformer being calibrated, and connect the standard precision current transformer in series in the same circuit.

[0071] The calibration parameters are set via the main control unit touchscreen: calibration points are set to four points: 1000A, 2000A, 3000A, and 4000A; the waveform is a 50Hz pure sine wave; the test duration is 30 seconds for each point. The system self-test program is started, and the power amplifier outputs a signal whose amplitude gradually decreases to zero to ensure that there is no residual current in the circuit.

[0072] The calibration parameters are set via the main control unit touchscreen: calibration points are set to five points: 1A, 5A, 20A, 100A, and 120A; the waveform is a 50Hz pure sine wave; the duration of each test point is 1 second. The system self-test program is started, and the power amplifier outputs a signal whose amplitude gradually decreases to zero to ensure that there is no residual current in the circuit.

[0073] After the self-test passes, the main control unit commands the signal generator to produce a 50Hz sine wave signal and simultaneously starts the power amplifier. Two sets of supercapacitors provide energy for the positive and negative half-waves of the power amplifier, respectively. After the power amplifier amplifies the signal, it outputs a precise 120A power frequency current in the primary circuit. The main control unit synchronously acquires the output signals of the standard current transformer and the calibrated CT, and calculates the ratio difference and angle difference in real time.

[0074] After completing the 120A test, the system automatically increases the output current to 100A and repeats the above measurement process until the 1A test is completed. Throughout the test, the system's adaptive closed-loop control algorithm monitors the output current waveform in real time and dynamically adjusts the drive signal to ensure that the total harmonic distortion of the output current remains below 0.5%.

[0075] After all test points are completed, the system automatically generates a calibration report, displaying the specific difference and angle difference curves and data tables for each test point, and makes a pass / fail conclusion. The entire calibration process takes about 5 minutes, and the total weight of the system does not exceed 25kg, achieving truly portable on-site calibration.

[0076] Therefore, this invention provides a lightweight field calibration system for ultra-high voltage (UHV) power grids based on capacitor energy storage and power amplification. This system addresses the prominent problems of existing calibration technologies, such as reliance on bulky power frequency current boosting devices, huge on-site energy consumption, and a single output waveform that cannot simulate complex operating conditions. It can achieve high-precision, multi-waveform high-current and high-voltage output in an integrated and portable manner, significantly improving the efficiency, adaptability, and data reliability of UHV field calibration. This provides advanced technical means for the accurate measurement and condition assessment of primary equipment in smart grids.

[0077] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the invention to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A lightweight on-site calibration system for ultra-high voltage power transmission based on capacitor energy storage and power amplification, characterized in that, include: The system includes a charging module, a power supply module, a power amplifier module, and a new type of calibrator. The charging module is used to charge the power module, the power module is used to provide energy signals to the power amplifier module, the power amplifier module is connected to the standard device and the test sample to form a test circuit, and the novel calibrator is connected to the charging module, the power module and the power amplifier module respectively to control the parameters of the test process.

2. The ultra-high voltage field lightweight calibration system according to claim 1, characterized in that, Also includes: The protection module is connected to the protection control unit of the new type of calibrator to realize the system's self-test and security verification.

3. The ultra-high voltage field lightweight calibration system according to claim 1, characterized in that, The charging module includes a charging interface and a first charging control unit. The first charging control unit is used to connect to the second charging control unit of the novel calibrator, receive charging commands, and charge the power module through the charging interface.

4. The ultra-high voltage field lightweight calibration system according to claim 1, characterized in that, The power module includes a supercapacitor bank and a power control unit. The power control unit is used to control the supercapacitor bank to release energy to the power amplifier module.

5. The ultra-high voltage field lightweight calibration system according to claim 4, characterized in that, The two supercapacitors in the supercapacitor bank adopt a symmetrical structure, have the same capacity and rated voltage, and are charged through independent charging management circuits.

6. The ultra-high voltage field lightweight calibration system according to claim 1, characterized in that, The power amplifier module includes a power amplifier group and a signal conditioning unit. The signal conditioning unit is used to receive instructions from the test control unit in the new calibrator to generate a preset high-precision standard waveform signal as the driving source of the power amplifier group.

7. The ultra-high voltage field lightweight calibration system according to claim 1, characterized in that, The novel calibration instrument also includes: Impedance testing unit is used to perform preliminary measurement of loop impedance before testing, providing a load matching reference for the system; The display unit is used for status monitoring, parameter setting, and result display to confirm the system status. The secondary measurement unit is used to synchronously acquire the output signals of the standard device and the test sample at a high sampling rate through its high-precision acquisition card, and to calculate the error parameters of the test sample at the current test point in real time using the built-in algorithm.

8. The ultra-high voltage (UHV) on-site lightweight calibration method implemented by the UHV on-site lightweight calibration system according to any one of claims 1-7, characterized in that, include: Step 1: Use the protection control module to perform system self-testing and participate in charge discharge; Step 2: Charge the supercapacitor bank in the power module through the charging module; Step 3: After the supercapacitor bank is fully charged, the supercapacitor bank is used to power the power amplifier module. The power amplifier module is controlled by a new type of calibrator to generate a high-precision standard waveform signal, and the protection control module is used for safety verification. Step 4: After the verification is passed, the standard waveform signal is amplified by the power amplifier group and output as a high-precision high current with set waveform and amplitude to the test circuit. Step 5: The output signals of the standard device and the test sample in the test circuit are collected synchronously by the new type of calibrator, and the error parameters of the test sample at the current test point are calculated in real time using the built-in algorithm; Step 6: Automatically step the output voltage to the next test point according to the preset sequence and repeat the measurement process of steps 1-5; Step 7: After all test points have been tested, generate a calibration report.

9. The method according to claim 8, characterized in that, Step 3 also includes: real-time monitoring of the voltage of the supercapacitor bank and the power amplifier output waveform, and dynamic adjustment of the amplitude of the high-precision standard waveform signal.

10. The method according to claim 8, characterized in that, In step 2, an intelligent equalization charging strategy is adopted during the charging process to ensure that the voltage consistency error between the two sets of supercapacitors in the supercapacitor group is less than a preset value.

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