Methods, devices, and equipment for correcting line errors in transformer load short-circuiting devices.

Abstract

This application relates to a method, apparatus, and device for correcting line errors in a transformer load short-circuit device. The method includes: calculating the measured short-circuit impedance percentage based on the measured voltage on the high-voltage side of the transformer and the rated high-voltage side voltage of the transformer; calculating the impedance resistance component based on the measured active power on the high-voltage side of the transformer and the rated capacity of the transformer, and calculating the impedance reactance component based on the measured short-circuit impedance percentage and the impedance resistance component; correcting the impedance resistance component using the line loss of the short-circuit conductor on the low-voltage side to obtain a corrected resistance component; calculating the reduced reactance value on the low-voltage side based on the power factor of the short-circuit conductor on the low-voltage side, and correcting the impedance reactance component to obtain a corrected reactance component; calculating the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component; correcting the corrected short-circuit impedance to a reference temperature, and outputting the standard short-circuit impedance percentage. This method can improve the detection accuracy of load loss and short-circuit impedance.

Description

Technical Field

[0001] This application relates to the field of transformer load testing technology, and in particular to a method, apparatus, computer equipment, computer-readable storage medium, and computer program product for correcting line errors of a transformer load short-circuiting device. Background Technology

[0002] Transformer load testing is a core test item in the factory inspection, energy efficiency rating, and performance evaluation of oil-immersed transformers. The conventional load testing method involves applying a test voltage to the high-voltage side of the transformer, and directly short-circuiting the low-voltage side using a high-current conductor (such as a copper busbar or flexible cable). A power analyzer is then used to directly collect parameters such as voltage, current, and active power on the high-voltage side, thereby calculating the transformer's load loss and short-circuit impedance percentage. This method is widely used in the industry due to its simple wiring and direct testing.

[0003] However, in actual testing, the low-voltage side short-circuit conductor itself has a certain resistance and reactance. Because the low-voltage side current is extremely large during load testing (reaching thousands of amperes), even if the resistance of the short-circuit conductor is small, the introduced resistive loss (i.e., active power loss) will significantly affect the measurement accuracy of load loss, leading to an overestimation of the load loss. Simultaneously, the reactance component of the short-circuit conductor causes an additional voltage drop, resulting in a deviation in the measurement of the short-circuit impedance voltage. Currently, the commonly used direct calculation method in the industry does not fully correct for the resistance and reactance errors introduced by the low-voltage side short-circuit conductor. While some techniques can compensate for resistive losses to a certain extent, they cannot effectively correct for the reactance component, resulting in a significant error between the calculated short-circuit impedance percentage and the actual transformer parameters.

[0004] Therefore, there is an urgent need for a method, device, computer equipment, computer-readable storage medium, and computer program product for correcting line errors in transformer load short-circuit devices, which can simultaneously eliminate measurement errors introduced by the resistance and reactance of the short-circuit conductor on the low-voltage side during transformer load testing, thereby improving the detection accuracy of load loss and short-circuit impedance. Summary of the Invention

[0005] Based on this, it is necessary to provide a method, device, computer equipment, computer-readable storage medium, and computer program product for correcting line errors of transformer load short-circuit devices that can simultaneously eliminate measurement errors introduced by the resistance and reactance of the short-circuit conductor on the low-voltage side during transformer load testing, and improve the detection accuracy of load loss and short-circuit impedance.

[0006] In a first aspect, this application provides a method for correcting line errors in a transformer load short-circuit device, including:

[0007] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0008] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0009] Based on the measured active power and the rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and the impedance resistance component, calculate the impedance reactance component.

[0010] The line loss of the short-circuited conductor on the low-voltage side is obtained, and the impedance resistance component is corrected using the line loss to obtain the corrected resistance component.

[0011] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0012] The corrected short-circuit impedance is calculated based on the corrected resistance component and the corrected reactance component.

[0013] The corrected short-circuit impedance is adjusted to the reference temperature, and the standard short-circuit impedance percentage is output.

[0014] In one embodiment, obtaining the measured voltage and measured active power of the transformer's high-voltage side, as well as the transformer's rated capacity and rated high-voltage side voltage, includes:

[0015] The control power analyzer is triggered synchronously with the test power supply to continuously collect the three-phase measured voltage, three-phase measured current and measured active power on the high-voltage side of the transformer within N power frequency cycles at a preset sampling frequency.

[0016] The average value of the three-phase measured voltage within the N power frequency cycles is calculated as the measured voltage, and the average value of the measured active power within the N power frequency cycles is calculated as the measured active power.

[0017] The test circuit is determined to be in a stable conducting state based on the measured three-phase current. If so, the rated capacity and rated high-voltage side voltage corresponding to the transformer are retrieved from the controller's local database or the test management system.

[0018] In one embodiment, the formula for calculating the measured short-circuit impedance percentage is:

[0019] Z kt0 =(U abc / U rh ) ×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases.rh This is the rated high-voltage side voltage;

[0020] The formula for calculating the impedance resistance component is:

[0021] R kt1 =P abc / (10×S r ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity;

[0022] The formula for calculating the impedance reactance component is as follows: Among them, I kt This represents the impedance reactance component.

[0023] In one embodiment, the step of correcting the impedance resistance component using the line loss to obtain the corrected resistance component includes:

[0024] Obtain the resistance loss of the short-circuited wire on the low-voltage side;

[0025] The difference between the impedance resistance component and the resistance loss is used as the corrected resistance component.

[0026] In one embodiment, the step of calculating the reduced low-voltage-side reactance value based on the power factor, and using the reduced low-voltage-side reactance value to correct the impedance reactance component to obtain the corrected reactance component includes:

[0027] Obtain the power factor of the short-circuited conductor on the low-voltage side;

[0028] Calculate the sine and tangent values ​​based on the power factor;

[0029] Calculate the reduced value of the low-voltage side reactance based on the impedance reactance component, the sine value, and the tangent value;

[0030] The difference between the impedance reactance component and the reduced value of the low-voltage side reactance is used as the corrected reactance component.

[0031] In one embodiment, correcting the short-circuit impedance to a reference temperature and outputting a standard short-circuit impedance percentage includes:

[0032] Calculate the corrected short-circuit impedance Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component;

[0033] The corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

[0034] Secondly, this application also provides a correction device for line errors of a transformer load short-circuit device, comprising:

[0035] The data acquisition module is used to acquire the measured voltage and measured active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer.

[0036] The first calculation module is used to calculate the measured short-circuit impedance percentage based on the measured voltage and the rated high-voltage side voltage, and to calculate the impedance resistance component based on the measured active power and the rated capacity, and to calculate the impedance reactance component based on the measured short-circuit impedance percentage and the impedance resistance component.

[0037] The resistance correction module is used to obtain the line loss of the short-circuited conductor on the low-voltage side, and to correct the impedance resistance component using the line loss to obtain the corrected resistance component.

[0038] The reactance correction module is used to obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0039] The second calculation module is used to calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component.

[0040] The temperature correction module is used to correct the modified short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

[0041] Thirdly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0042] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0043] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0044] Based on the measured active power and the rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and the impedance resistance component, calculate the impedance reactance component.

[0045] The line loss of the short-circuited conductor on the low-voltage side is obtained, and the impedance resistance component is corrected using the line loss to obtain the corrected resistance component.

[0046] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0047] The corrected short-circuit impedance is calculated based on the corrected resistance component and the corrected reactance component.

[0048] The corrected short-circuit impedance is adjusted to the reference temperature, and the standard short-circuit impedance percentage is output.

[0049] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the following steps:

[0050] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0051] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0052] Based on the measured active power and the rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and the impedance resistance component, calculate the impedance reactance component.

[0053] The line loss of the short-circuited conductor on the low-voltage side is obtained, and the impedance resistance component is corrected using the line loss to obtain the corrected resistance component.

[0054] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0055] The corrected short-circuit impedance is calculated based on the corrected resistance component and the corrected reactance component.

[0056] The corrected short-circuit impedance is adjusted to the reference temperature, and the standard short-circuit impedance percentage is output.

[0057] Fifthly, this application also provides a computer program product, including a computer program that, when executed by a processor, performs the following steps:

[0058] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0059] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0060] Based on the measured active power and the rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and the impedance resistance component, calculate the impedance reactance component.

[0061] The line loss of the short-circuited conductor on the low-voltage side is obtained, and the impedance resistance component is corrected using the line loss to obtain the corrected resistance component.

[0062] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0063] The corrected short-circuit impedance is calculated based on the corrected resistance component and the corrected reactance component.

[0064] The corrected short-circuit impedance is adjusted to the reference temperature, and the standard short-circuit impedance percentage is output.

[0065] The aforementioned method, apparatus, computer equipment, computer-readable storage medium, and computer program product for correcting line errors in transformer load short-circuit devices achieve dual independent correction of the resistive loss and reactive component introduced by the short-circuit conductor on the low-voltage side by acquiring the measured voltage, measured active power, rated capacity, and rated high-voltage side voltage of the transformer high-voltage side, and calculating the measured short-circuit impedance percentage, impedance resistance component, and impedance reactance component based on these parameters. Specifically, the resistive component is first subtracted using line losses to eliminate the load loss measurement deviation caused by the active power loss of the short-circuit conductor; then, the reactance reduction value is calculated using the low-voltage side power factor and the reactance component is subtracted to eliminate the short-circuit impedance voltage measurement deviation caused by the reactance of the short-circuit conductor. On this basis, the short-circuit impedance is recalculated based on the corrected resistive and reactance components and corrected to the standard reference temperature, finally outputting an accurate standard short-circuit impedance percentage. Through the synergistic processing of resistance correction and reactance correction, the resistance error and reactance error of the short-circuited conductor on the low-voltage side can be eliminated simultaneously, significantly improving the measurement accuracy of load loss and short-circuit impedance in transformer load tests, and making the test results closer to the actual electrical parameters of the transformer. Attached Figure Description

[0066] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0067] Figure 1 This is a flowchart illustrating a method for correcting line errors in a transformer load short-circuit device in one embodiment.

[0068] Figure 2 This is a flowchart illustrating a method for correcting line errors in a transformer load short-circuit device in yet another embodiment.

[0069] Figure 3 This is a flowchart illustrating a method for correcting line errors in a transformer load short-circuit device, as described in another embodiment.

[0070] Figure 4 This is a structural block diagram of a correction device for line error of a transformer load short-circuit device in one embodiment;

[0071] Figure 5 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0072] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0073] It should be noted that the terms "first," "second," etc., used in this application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0074] In one exemplary embodiment, such as Figure 1 As shown, a method for correcting line errors in a transformer load short-circuit device is provided, comprising the following steps S102 to S114. Wherein:

[0075] Step S102: Obtain the measured voltage and measured active power of the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer.

[0076] Specifically, under the condition of applying a test voltage to the high-voltage side of the transformer and short-circuiting the low-voltage side through a high-current conductor, the voltage sampling terminal of the power analyzer is connected in parallel to both ends of the high-voltage winding, and the current sampling terminal is connected in series to the high-voltage circuit without passing through a voltage transformer or current transformer to avoid additional phase and amplitude errors. During the test, the power analyzer collects the line voltage (or calculated phase voltage) and the total three-phase active power on the high-voltage side in real time. To ensure the representativeness and stability of the data, the instantaneous values ​​of multiple power frequency cycles are usually collected continuously and the arithmetic mean is calculated. This average value is used as the measured voltage and measured active power in this step. For example, when conducting a load test on a transformer with a rated capacity of 10MVA and a rated high-voltage side voltage of 35kV, the power analyzer can measure an effective value of approximately 35.2kV for the high-voltage side line voltage and approximately 86.5kW for the total three-phase active power. These values ​​directly reflect the actual terminal voltage and active power consumed by the transformer under test conditions. On the other hand, the rated capacity and rated high-voltage side voltage of the transformer are inherent nameplate parameters of the equipment and do not depend on the real-time measurement of the current test. Instead, they are pre-stored in the controller's local parameter library or test management system.

[0077] Step S104: Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage.

[0078] Specifically, the actual voltage measured on the high-voltage side of the transformer under the current load test conditions is normalized to the rated voltage, and the initial measured value of the short-circuit impedance is expressed as a percentage. The physical meaning of the short-circuit impedance percentage is as follows: when a short circuit occurs on the low-voltage side of the transformer, a voltage at the rated frequency is applied to the high-voltage side to bring the high-voltage side current to its rated value. The ratio of the applied voltage to the rated voltage is the short-circuit impedance percentage, reflecting the magnitude of the leakage impedance inside the transformer. In the test wiring of this method, the low-voltage side is directly short-circuited through a high-current conductor; therefore, the measured voltage U on the high-voltage side is... abc In essence, it involves causing the transformer to generate the applied voltage corresponding to the current short-circuit current. (U) abc Divide by the rated high-voltage side voltage Urh and multiply by 100% to obtain the initial short-circuit impedance percentage Z without any error correction. kt_0 .

[0079] Step S106: Calculate the impedance resistance component based on the measured active power and rated capacity, and calculate the impedance reactance component based on the measured short-circuit impedance percentage and impedance resistance component.

[0080] Specifically, the resistance component is first calculated using the ratio between the measured active power and the rated capacity. This is because all the active power measured in the transformer load test is mainly consumed by the transformer's own winding resistance and the resistance of the short-circuit conductor on the low-voltage side, while the rated capacity serves as the reference apparent power. By using the ratio of the two and supplementing it with a standardized proportional conversion, the percentage of the resistance component in the short-circuit impedance can be obtained. After calculating the resistance component, the measured short-circuit impedance percentage obtained in step S104 is combined with the square relationship between resistance and reactance, which together constitute the total short-circuit impedance. That is, the square root is taken after subtracting the square of the resistance component from the square of the total short-circuit impedance, thus deriving the reactance component in reverse. This decomposition process separates the originally single short-circuit impedance measurement value into two independent components: resistance and reactance, clearly separating the two types of physical effects that were mixed together.

[0081] Step S108: Obtain the line loss of the short-circuited conductor on the low-voltage side, and use the line loss to correct the impedance resistance component to obtain the corrected resistance component.

[0082] Specifically, the line loss of the short-circuited conductor on the low-voltage side refers to the active power loss generated by the resistance of the short-circuited conductor itself under the action of the test current. This loss is superimposed on the actual load loss of the transformer, resulting in an overestimation of the measured impedance resistance component. The line loss can be obtained through pre-calibration or real-time calculation: for example, the ohmic value of the conductor resistance can be calculated based on the material, cross-sectional area, length of the short-circuited conductor, and the actual low-voltage side current value, and then the active power value of the line loss can be obtained by combining the product of the square of the current and the resistance; alternatively, the conductor loss parameters that have been pre-measured and stored in the controller can be directly used, as these parameters are fixed and known according to the conductor specifications. Regardless of the method used, the final result is a specific value representing the conductor resistance loss. The correction process involves subtracting the line loss from the impedance resistance component calculated in step S106, because the original impedance resistance component includes both the actual resistance of the transformer itself and the additional resistance loss of the conductor. After subtraction, what remains is the pure resistance component contributed only by the transformer's own winding resistance, i.e., the corrected resistance component.

[0083] Step S110: Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0084] Specifically, the power factor of the short-circuited conductor on the low-voltage side reflects the phase relationship between its active power loss and apparent power under the AC test current. Since the conductor has both resistance and reactance, its power factor is usually less than 1. This power factor can be obtained manually by pre-estimating it based on the conductor specifications and test current and then inputting it into the controller, or it can be acquired in real-time by installing measuring equipment on the low-voltage side. After obtaining the power factor, the corresponding sine and tangent values ​​can be derived based on trigonometric relationships. Then, combined with the total impedance reactance component, the reactance reduction value contributed by the short-circuited conductor on the low-voltage side can be calculated, which is the equivalent value of the conductor reactance referred to the high-voltage side. This is because the current on the low-voltage side is extremely large while the current on the high-voltage side is relatively small. The actual reactance of the conductor needs to be reduced to the high-voltage side according to the voltage ratio or current ratio before it can be directly added to or subtracted from the impedance reactance component measured on the high-voltage side. The specific correction method is to subtract the aforementioned low-voltage side reactance reduction value from the impedance reactance component calculated in step S106. The reason for using subtraction instead of superposition is that the original measured impedance reactance component already includes the transformer's own true reactance and the additional reactance of the short-circuited wire. After subtracting the part contributed by the wire, what remains is the true reactance component generated only by the transformer's own leakage flux.

[0085] Step S112: Calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component.

[0086] Specifically, since the resistive and reactive components are orthogonal in an AC circuit, they together constitute the vector magnitude of the total impedance. Specifically, the corrected short-circuit impedance is calculated by squaring the corrected resistive and reactive components respectively, summing them, and then taking the square root of the sum to obtain the corrected short-circuit impedance expressed as a percentage or numerical value. This process essentially synthesizes the two orthogonal components after resistance and reactance corrections, restoring the true short-circuit impedance value that reflects only the transformer's own characteristics after eliminating short-circuit conductor errors. Unlike the measured short-circuit impedance percentage calculated in step S104, the corrected short-circuit impedance obtained in this step has eliminated the dual interference of the low-voltage side short-circuit conductor resistance and reactance, thus its value is closer to the transformer's theoretical design value or factory-set value. This corrected short-circuit impedance will be used as input for the subsequent temperature correction step to convert to the final impedance value at the standard reference temperature.

[0087] Step S114: Correct the short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

[0088] Specifically, the resistance of transformer windings has a positive temperature coefficient, meaning that the resistance increases with temperature. While the resistive component of the short-circuit impedance changes with temperature, the reactant component is negligibly affected by temperature. Therefore, the overall short-circuit impedance also changes with temperature. To ensure comparability of test results measured at different temperatures, national standards or industry specifications typically require that the short-circuit impedance measured under load tests be uniformly corrected to a certain reference temperature (e.g., 75°C for oil-immersed transformers). The correction process is based on the known temperature coefficient and the actual winding temperature during the test. A standardized temperature conversion formula is used to convert the corrected short-circuit impedance obtained in step S112 from the actual test temperature to its equivalent value at the reference temperature. The resulting standard short-circuit impedance percentage reflects the transformer's performance under uniform reference conditions, eliminating the influence of temperature differences on the resistive component. This allows for an objective evaluation of whether the transformer's short-circuit impedance meets design requirements or energy efficiency standards.

[0089] The aforementioned method for correcting line errors in transformer load short-circuit devices achieves dual independent correction of the resistance loss and reactance components introduced by the short-circuit conductors on the low-voltage side by acquiring the measured voltage, measured active power, rated capacity, and rated high-voltage side voltage of the transformer high-voltage side, and calculating the measured short-circuit impedance percentage, resistance component, and reactance component based on these parameters. Specifically, the resistance component is first subtracted using line losses to eliminate the load loss measurement deviation caused by the active power loss of the short-circuit conductors; then, the reactance reduction value is calculated using the low-voltage side power factor, and the reactance component is subtracted to eliminate the short-circuit impedance voltage measurement deviation caused by the reactance of the short-circuit conductors. Based on this, the short-circuit impedance is recalculated using the corrected resistance and reactance components and corrected to the standard reference temperature, ultimately outputting an accurate standard short-circuit impedance percentage. Through the synergistic processing of resistance and reactance corrections, the resistance and reactance errors of the short-circuit conductors on the low-voltage side can be eliminated simultaneously, significantly improving the measurement accuracy of load loss and short-circuit impedance in transformer load tests, making the test results closer to the actual electrical parameters of the transformer.

[0090] In one exemplary embodiment, such as Figure 2 As shown, the measured voltage and measured active power of the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer, are obtained, including:

[0091] Step S202: Control the power analyzer to be triggered synchronously with the test power supply, and continuously collect the three-phase measured voltage, three-phase measured current and measured active power on the high-voltage side of the transformer within N power frequency cycles at a preset sampling frequency.

[0092] Step S204: Calculate the average value of the three-phase measured voltage over N power frequency cycles as the measured voltage, and calculate the average value of the measured active power over N power frequency cycles as the measured active power.

[0093] Step S206: Determine whether the test circuit is in a stable conducting state based on the measured three-phase current. If so, retrieve the rated capacity and rated high-voltage side voltage corresponding to the transformer from the controller's local database or the test management system.

[0094] Specifically, firstly, the power analyzer and the test power supply are triggered synchronously to align the start time of data acquisition with the rising edge of the power supply output, avoiding measurement deviations caused by random sampling phases. Then, at a preset sampling frequency (e.g., 128 points per cycle), the three-phase measured voltage, three-phase measured current, and measured active power are continuously acquired over N complete power frequency cycles (e.g., 20 cycles). After acquisition, the arithmetic mean of the three-phase measured voltage over these N cycles is taken as the final measured voltage; the arithmetic mean of the measured active power over these N cycles is also taken as the final measured active power. Before formally using these averages, the acquired three-phase measured current is used to determine whether the test circuit is in a stable conducting state, for example, whether the fluctuation of the effective current value over several consecutive cycles is less than a set threshold. Only after the circuit is determined to be stable is the rated capacity and rated high-voltage side voltage of the transformer under test retrieved from the controller's local database or the test management system. If the circuit is unstable, data acquisition may be restarted or an alarm may be issued.

[0095] In this embodiment, synchronous triggering and multi-cycle averaging are employed to effectively suppress the impact of grid frequency fluctuations, harmonic interference, and random noise on voltage and power measurements, significantly improving the repeatability and accuracy of the measured data. Pre-judgment of loop stability is performed using the collected three-phase measured current, preventing abnormal conditions such as poor contact on the low-voltage side or transient power supply fluctuations from introducing abnormal data into the correction process, thus preventing distortion of the correction results due to erroneous data. Rated parameters are automatically retrieved only after loop stability is confirmed, improving the robustness and automation level of the entire correction method and reducing the risk of manual intervention and misoperation.

[0096] In an exemplary embodiment, the formula for calculating the measured short-circuit impedance percentage is as follows:

[0097] Z kt0 =(U abc / U rh )×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases. rh This is the rated high-voltage side voltage;

[0098] The formula for calculating the impedance resistance component is:

[0099] R kt1 =P abc / (10×Sr ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity;

[0100] The formula for calculating the impedance reactance component is: Among them, I kt This represents the impedance reactance component.

[0101] Specifically, firstly, the three-phase measured voltage U abc Divide by the rated high-voltage side voltage U rh Multiply by 100% to get the measured short-circuit impedance percentage Z. kt0 This involves normalizing the current test voltage to the rated voltage, directly reflecting the initial short-circuit impedance before error correction. Secondly, the measured active power P... abc Divide by 10 times the rated capacity S r The impedance resistance component R is obtained. kt1 The coefficient 10 in this formula is used to adjust the power-to-capacity ratio into a percentage, conforming to the conventions of expressing short-circuit impedance in the power industry. Finally, based on the geometric relationship of the impedance triangle, the square of the total short-circuit impedance is equal to the sum of the squares of the resistance component and the squares of the reactance component. By calculating the square root of the measured short-circuit impedance percentage minus the square of the resistance component, the impedance-reactance component I is obtained. kt These three formulas sequentially complete the numerical decomposition from the original measured value to the total impedance, then to the resistance component, and finally to the reactance component, providing a quantitative basis for subsequent correction of resistance and reactance errors.

[0102] In this embodiment, abstract electrical physical quantities are transformed into specific percentage values ​​for calculation, making it easy to directly compare short-circuit impedance, resistance components, and reactance components with standard limits. By utilizing the square root relationship of the impedance triangle, the resistance and reactance components are accurately separated from the single total impedance, achieving decoupling of two different types of physical characteristic errors. This allows for independent correction of conductor resistance and conductor reactance separately, avoiding cross-interference.

[0103] In one exemplary embodiment, the impedance resistance component is corrected using line loss to obtain the corrected resistance component, including:

[0104] Obtain the resistance loss of the short-circuited wire on the low-voltage side;

[0105] The difference between the impedance resistance component and the resistance loss is used as the corrected resistance component.

[0106] Specifically, the resistance loss of the short-circuited conductor on the low-voltage side is first obtained. This resistance loss refers to the active power loss caused by the conductor's own resistance under the test current. This loss can be calculated in advance using the conductor material, cross-sectional area, length, and test current, or it can be directly read from the conductor loss parameters stored in the controller. Then, the calculated impedance resistance component (which includes both the transformer's actual resistance and the conductor's additional resistance) is subtracted from the obtained resistance loss, and the difference is taken as the corrected resistance component. In the originally measured impedance resistance component, the conductor resistance loss is a redundant additional component. After subtracting it, what remains is the pure resistance component contributed only by the transformer's own winding resistance. This correction operation is direct and linear, without introducing nonlinear transformations or approximate fitting.

[0107] In this embodiment, the resistance loss of the conductor is directly deducted, eliminating the interference of the short-circuited conductor resistance on the load loss measurement, so that the corrected resistance component can truly reflect the copper loss characteristics of the transformer winding. This correction method is not dependent on the transformer model or capacity; it is universal as long as the conductor specifications are fixed and the resistance loss is known, and has good portability and adaptability.

[0108] In one exemplary embodiment, such as Figure 3 As shown, the reduced value of the low-voltage side reactance is calculated based on the power factor. This reduced value is then used to correct the impedance reactance component, resulting in the corrected reactance component, which includes:

[0109] Step S302: Obtain the power factor of the short-circuited conductor on the low-voltage side;

[0110] Step S304: Calculate the sine and tangent values ​​based on the power factor;

[0111] Step S306: Calculate the reduced value of the low-voltage side reactance based on the impedance reactance components, sine value, and tangent value.

[0112] Step S308: The difference between the impedance reactance component and the reduced value of the low-voltage side reactance is used as the corrected reactance component.

[0113] Specifically, firstly, the power factor of the short-circuited conductor on the low-voltage side is obtained. This power factor reflects the ratio of the conductor's resistance to its reactance under AC test current, and is typically less than 1. It can be estimated in advance or measured in real time. Next, the corresponding sine and tangent values ​​are calculated using trigonometric functions based on this power factor: the sine value characterizes the proportion of reactive power in the conductor, while the tangent value reflects the ratio of resistance to reactance. Then, based on the existing impedance-reactance component (which combines the transformer's own reactance and the conductor's reactance), the sine value, and the tangent value, the reduced reactance value on the low-voltage side is calculated. This is the equivalent value of the conductor's own reactance converted to the high-voltage side value. Because the low-voltage side current is much larger than the high-voltage side current, the low-voltage side reactance value cannot be directly subtracted from the reactance component measured on the high-voltage side. Finally, the reduced value is subtracted from the original impedance-reactance component, and the difference is used as the corrected reactance component.

[0114] In this embodiment, the sine and tangent values ​​are derived from the power factor, establishing a complete trigonometric function chain from the measurable power factor to the reactance reduction. This allows the entire correction process to rely on only one input parameter (power factor), reducing the difficulty of data acquisition. By calculating the reduced reactance value on the low-voltage side, the problem of reactance not being directly subtractable due to the large difference in current between the high and low voltage sides is solved. The conductor reactance is equivalently converted to the high-voltage side, ensuring the dimensional consistency and physical correctness of the correction calculation.

[0115] In one exemplary embodiment, the corrected short-circuit impedance is adjusted to a reference temperature, and a standard short-circuit impedance percentage is output, including:

[0116] Calculate the corrected short-circuit impedance Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component;

[0117] The corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

[0118] Specifically, firstly, the corrected resistance component R is used. kt and corrected reactance component I kt_hv The corrected short-circuit impedance Z is calculated using the arithmetic square root of the sum of squares (i.e., the Pythagorean theorem). kt_ok This is because resistance and reactance are orthogonal in an AC circuit, and the magnitude of the total impedance is equal to the square root of the sum of their squares. Z is calculated as follows. kt_okThen, it is corrected to a reference temperature of 75℃. Temperature correction is necessary because the resistance of the transformer windings changes with temperature, while the resistive component of the short-circuit impedance has a positive temperature coefficient, and the reactance component is negligibly affected by temperature. Without correction, short-circuit impedances measured at different test temperatures cannot be compared laterally. A standardized temperature conversion formula is used to convert the Z-value at the actual test temperature... kt_ok Converted to the equivalent value at 75℃, the final output is the standard short-circuit impedance percentage.

[0119] In this embodiment, a 75°C reference temperature correction is introduced to eliminate the influence of ambient temperature differences on the measurement results. This ensures that short-circuit impedances measured under different seasons, regions, and test conditions are comparable and the final output is a standard short-circuit impedance percentage, which can be directly used by test personnel, quality inspection agencies, or energy efficiency certification systems without secondary conversion, thus improving testing efficiency and data utilization convenience. The complete temperature correction process, combined with the preceding resistance and reactance double correction, ensures that the final result eliminates both short-circuit wire errors and temperature drift effects, truly reflecting the transformer's real short-circuit impedance performance under standard reference conditions.

[0120] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0121] Based on the same inventive concept, this application also provides a device for correcting line errors of a transformer load short-circuit device, which is used to implement the above-described method for correcting line errors of a transformer load short-circuit device. The solution provided by this device is similar to the solution described in the above-described method. Therefore, the specific limitations of one or more embodiments of the device for correcting line errors of a transformer load short-circuit device provided below can be found in the limitations of the method for correcting line errors of a transformer load short-circuit device described above, and will not be repeated here.

[0122] In one exemplary embodiment, such as Figure 4 As shown, a correction device for line error of a transformer load short-circuit device is provided, comprising:

[0123] The data acquisition module 402 is used to acquire the measured voltage and measured active power of the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer.

[0124] The first calculation module 404 is used to calculate the measured short-circuit impedance percentage based on the measured voltage and the rated high-voltage side voltage, and to calculate the impedance resistance component based on the measured active power and the rated capacity, and to calculate the impedance reactance component based on the measured short-circuit impedance percentage and the impedance resistance component.

[0125] The resistance correction module 406 is used to obtain the line loss of the short-circuited conductor on the low-voltage side, and to correct the impedance resistance component using the line loss to obtain the corrected resistance component.

[0126] The reactance correction module 408 is used to obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0127] The second calculation module 410 is used to calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component.

[0128] Temperature correction module 412 is used to correct the short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

[0129] In an exemplary embodiment, the data acquisition module 402 is specifically used to control the power analyzer and the test power supply to trigger synchronously, and to continuously acquire the three-phase measured voltage, three-phase measured current and measured active power of the transformer high-voltage side within N power frequency cycles at a preset sampling frequency; calculate the average value of the three-phase measured voltage within N power frequency cycles as the measured voltage, calculate the average value of the measured active power within N power frequency cycles as the measured active power; determine whether the test circuit is in a stable conducting state based on the three-phase measured current, and if so, retrieve the rated capacity and rated high-voltage side voltage corresponding to the transformer from the controller's local database or the test management system.

[0130] In an exemplary embodiment, the formula for calculating the measured short-circuit impedance percentage is as follows:

[0131] Z kt0 =(U abc / U rh )×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases. rh This is the rated high-voltage side voltage;

[0132] The formula for calculating the impedance resistance component is:

[0133] Rkt1 =P abc / (10×S r ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity;

[0134] The formula for calculating the impedance reactance component is: Among them, I kt This represents the impedance reactance component.

[0135] In an exemplary embodiment, the resistance correction module 406 is specifically used to obtain the resistance loss of the short-circuited conductor on the low-voltage side; and to use the difference between the impedance resistance component and the resistance loss as the correction resistance component.

[0136] In an exemplary embodiment, the reactance correction module 408 is specifically used to obtain the power factor of the short-circuited conductor on the low-voltage side; calculate the sine and tangent values ​​based on the power factor; calculate the reduced reactance value on the low-voltage side based on the impedance reactance component, the sine value, and the tangent value; and use the difference between the impedance reactance component and the reduced reactance value on the low-voltage side as the corrected reactance component.

[0137] In one exemplary embodiment, the temperature correction module 412 is specifically used to calculate the corrected short-circuit impedance. Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component, the corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

[0138] Each module in the aforementioned transformer load short-circuit device line error correction device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0139] In one exemplary embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 5As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores data. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network connection. When executed by the processor, the computer program implements a method for correcting line errors in a transformer load short-circuit device.

[0140] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0141] In one exemplary embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0142] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0143] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0144] Based on the measured active power and rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and impedance resistance component, calculate the impedance reactance component.

[0145] Obtain the line loss of the short-circuited conductor on the low-voltage side, and use the line loss to correct the impedance resistance component to obtain the corrected resistance component.

[0146] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0147] Calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component;

[0148] Correct the short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

[0149] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0150] The control power analyzer is triggered synchronously with the test power supply to continuously collect the three-phase measured voltage, three-phase measured current and measured active power on the high-voltage side of the transformer within N power frequency cycles at a preset sampling frequency.

[0151] Calculate the average value of the three-phase measured voltage over N power frequency cycles as the measured voltage, and calculate the average value of the measured active power over N power frequency cycles as the measured active power.

[0152] The test circuit is determined to be in a stable conducting state based on the measured three-phase current. If so, the rated capacity and rated high-voltage side voltage corresponding to the transformer are retrieved from the controller's local database or the test management system.

[0153] In one embodiment, the formula for calculating the percentage of measured short-circuit impedance is:

[0154] Z kt0 =(U abc / U rh )×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases. rh This is the rated high-voltage side voltage;

[0155] The formula for calculating the impedance resistance component is:

[0156] R kt1 =P abc / (10×S r ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity;

[0157] The formula for calculating the impedance reactance component is: Among them, I kt This represents the impedance reactance component.

[0158] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0159] Obtain the resistance loss of the short-circuited wire on the low-voltage side;

[0160] The difference between the impedance resistance component and the resistance loss is used as the corrected resistance component.

[0161] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0162] Obtain the power factor of the short-circuited conductor on the low-voltage side;

[0163] Calculate the sine and tangent values ​​based on the power factor;

[0164] Calculate the reduced value of the low-voltage side reactance based on the impedance reactance components, sine value, and tangent value.

[0165] The difference between the impedance reactance component and the reduced value of the low-voltage side reactance is used as the corrected reactance component.

[0166] In one embodiment, the processor, when executing a computer program, also performs the following steps:

[0167] Calculate the corrected short-circuit impedance Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component;

[0168] The corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

[0169] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0170] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0171] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0172] Based on the measured active power and rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and impedance resistance component, calculate the impedance reactance component.

[0173] Obtain the line loss of the short-circuited conductor on the low-voltage side, and use the line loss to correct the impedance resistance component to obtain the corrected resistance component.

[0174] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0175] Calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component;

[0176] Correct the short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

[0177] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0178] The control power analyzer is triggered synchronously with the test power supply to continuously collect the three-phase measured voltage, three-phase measured current and measured active power on the high-voltage side of the transformer within N power frequency cycles at a preset sampling frequency.

[0179] Calculate the average value of the three-phase measured voltage over N power frequency cycles as the measured voltage, and calculate the average value of the measured active power over N power frequency cycles as the measured active power.

[0180] The test circuit is determined to be in a stable conducting state based on the measured three-phase current. If so, the rated capacity and rated high-voltage side voltage corresponding to the transformer are retrieved from the controller's local database or the test management system.

[0181] In one embodiment, the formula for calculating the percentage of measured short-circuit impedance is:

[0182] Z kt0 =(U abc / U rh )×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases. rh This is the rated high-voltage side voltage;

[0183] The formula for calculating the impedance resistance component is:

[0184] R kt1 =P abc / (10×S r ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity;

[0185] The formula for calculating the impedance reactance component is: Among them, I kt This represents the impedance reactance component.

[0186] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0187] Obtain the resistance loss of the short-circuited wire on the low-voltage side;

[0188] The difference between the impedance resistance component and the resistance loss is used as the corrected resistance component.

[0189] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0190] Obtain the power factor of the short-circuited conductor on the low-voltage side;

[0191] Calculate the sine and tangent values ​​based on the power factor;

[0192] Calculate the reduced value of the low-voltage side reactance based on the impedance reactance components, sine value, and tangent value.

[0193] The difference between the impedance reactance component and the reduced value of the low-voltage side reactance is used as the corrected reactance component.

[0194] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0195] Calculate the corrected short-circuit impedance Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component;

[0196] The corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

[0197] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0198] Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer;

[0199] Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage;

[0200] Based on the measured active power and rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and impedance resistance component, calculate the impedance reactance component.

[0201] Obtain the line loss of the short-circuited conductor on the low-voltage side, and use the line loss to correct the impedance resistance component to obtain the corrected resistance component.

[0202] Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component.

[0203] Calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component;

[0204] Correct the short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

[0205] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0206] The control power analyzer is triggered synchronously with the test power supply to continuously collect the three-phase measured voltage, three-phase measured current and measured active power on the high-voltage side of the transformer within N power frequency cycles at a preset sampling frequency.

[0207] Calculate the average value of the three-phase measured voltage over N power frequency cycles as the measured voltage, and calculate the average value of the measured active power over N power frequency cycles as the measured active power.

[0208] The test circuit is determined to be in a stable conducting state based on the measured three-phase current. If so, the rated capacity and rated high-voltage side voltage corresponding to the transformer are retrieved from the controller's local database or the test management system.

[0209] In one embodiment, the formula for calculating the percentage of measured short-circuit impedance is:

[0210] Z kt0 =(U abc / U rh )×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases. rh This is the rated high-voltage side voltage;

[0211] The formula for calculating the impedance resistance component is:

[0212] R kt1 =P abc / (10×S r ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity;

[0213] The formula for calculating the impedance reactance component is: Among them, I kt This represents the impedance reactance component.

[0214] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0215] Obtain the resistance loss of the short-circuited wire on the low-voltage side;

[0216] The difference between the impedance resistance component and the resistance loss is used as the corrected resistance component.

[0217] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0218] Obtain the power factor of the short-circuited conductor on the low-voltage side;

[0219] Calculate the sine and tangent values ​​based on the power factor;

[0220] Calculate the reduced value of the low-voltage side reactance based on the impedance reactance components, sine value, and tangent value.

[0221] The difference between the impedance reactance component and the reduced value of the low-voltage side reactance is used as the corrected reactance component.

[0222] In one embodiment, when the computer program is executed by a processor, it also performs the following steps:

[0223] Calculate the corrected short-circuit impedance Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component;

[0224] The corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

[0225] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0226] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0227] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0228] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for correcting line errors in a transformer load short-circuit device, characterized in that, The method includes: Obtain the measured voltage and active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer; Calculate the percentage of measured short-circuit impedance based on the measured voltage and the rated high-voltage side voltage; Based on the measured active power and the rated capacity, calculate the impedance resistance component, and based on the measured short-circuit impedance percentage and the impedance resistance component, calculate the impedance reactance component. The line loss of the short-circuited conductor on the low-voltage side is obtained, and the impedance resistance component is corrected using the line loss to obtain the corrected resistance component. Obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component. The corrected short-circuit impedance is calculated based on the corrected resistance component and the corrected reactance component. The corrected short-circuit impedance is adjusted to the reference temperature, and the standard short-circuit impedance percentage is output.

2. The method according to claim 1, characterized in that, The acquisition of the measured voltage and measured active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer, includes: The control power analyzer is triggered synchronously with the test power supply to continuously collect the three-phase measured voltage, three-phase measured current and measured active power on the high-voltage side of the transformer within N power frequency cycles at a preset sampling frequency. The average value of the three-phase measured voltage within the N power frequency cycles is calculated as the measured voltage, and the average value of the measured active power within the N power frequency cycles is calculated as the measured active power. The test circuit is determined to be in a stable conducting state based on the measured three-phase current. If so, the rated capacity and rated high-voltage side voltage corresponding to the transformer are retrieved from the controller's local database or the test management system.

3. The method according to claim 2, characterized in that, The formula for calculating the percentage of the measured short-circuit impedance is as follows: Z kt0 =(U abc / U rh )×100%; where Z kt0 U represents the percentage of the measured short-circuit impedance. abc U is the measured voltage of the three phases. rh This is the rated high-voltage side voltage; The formula for calculating the impedance resistance component is: R kt1 =P abc / (10×S r ); where R kt1 P is the impedance / resistance component. abc To measure the active power, S r Rated capacity; The formula for calculating the impedance reactance component is as follows: Among them, I kt This represents the impedance reactance component.

4. The method according to claim 1, characterized in that, The step of correcting the impedance resistance component using the line loss to obtain the corrected resistance component includes: Obtain the resistance loss of the short-circuited wire on the low-voltage side; The difference between the impedance resistance component and the resistance loss is used as the corrected resistance component.

5. The method according to claim 1, characterized in that, The step of calculating the reduced low-voltage side reactance value based on the power factor, and using the reduced low-voltage side reactance value to correct the impedance reactance component to obtain the corrected reactance component includes: Obtain the power factor of the short-circuited conductor on the low-voltage side; Calculate the sine and tangent values ​​based on the power factor; Calculate the reduced value of the low-voltage side reactance based on the impedance reactance component, the sine value, and the tangent value; The difference between the impedance reactance component and the reduced value of the low-voltage side reactance is used as the corrected reactance component.

6. The method according to claim 1, characterized in that, The step of correcting the short-circuit impedance to a reference temperature and outputting a standard short-circuit impedance percentage includes: Calculate the corrected short-circuit impedance Among them, Z kt_ok To correct the short-circuit impedance, R kt To correct the resistive component, I kt_hv To correct the reactance component; The corrected short-circuit impedance is adjusted to a reference temperature of 75°C to obtain the standard short-circuit impedance percentage.

7. A device for correcting line errors in a transformer load short-circuit device, characterized in that, The device includes: The data acquisition module is used to acquire the measured voltage and measured active power on the high-voltage side of the transformer, as well as the rated capacity and rated high-voltage side voltage of the transformer. The first calculation module is used to calculate the measured short-circuit impedance percentage based on the measured voltage and the rated high-voltage side voltage, and to calculate the impedance resistance component based on the measured active power and the rated capacity, and to calculate the impedance reactance component based on the measured short-circuit impedance percentage and the impedance resistance component. The resistance correction module is used to obtain the line loss of the short-circuited conductor on the low-voltage side, and to correct the impedance resistance component using the line loss to obtain the corrected resistance component. The reactance correction module is used to obtain the power factor of the short-circuited conductor on the low-voltage side, calculate the reduced reactance value on the low-voltage side based on the power factor, and use the reduced reactance value on the low-voltage side to correct the impedance reactance component to obtain the corrected reactance component. The second calculation module is used to calculate the corrected short-circuit impedance based on the corrected resistance component and the corrected reactance component. The temperature correction module is used to correct the modified short-circuit impedance to the reference temperature and output the standard short-circuit impedance percentage.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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