A voltage monitoring method and system for transformers based on on-load tap changers

Abstract

This invention relates to the field of transformer voltage monitoring technology, specifically disclosing a voltage monitoring method and system for a transformer based on an on-load tap changer. The method includes: acquiring real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data; obtaining real-time no-load power loss values ​​based on the real-time input voltage data and real-time winding current data; and obtaining the load power factor based on the real-time winding current data. This invention can accurately calculate the real-time no-load power loss values ​​and real-time load power loss values ​​of the transformer by real-time monitoring of the transformer's winding temperature, input voltage, and winding current. This allows for the determination of the adjustment values ​​for the on-load tap changer and the adjustment range of the on-load tap changer, ensuring that the on-load tap changer can adjust in a timely and accurate manner to cope with voltage fluctuations, thereby ensuring that the transformer's output voltage remains stable near its rated value.

Description

Technical Field

[0001] This invention relates to the field of transformer voltage monitoring technology, and in particular to a voltage monitoring method and system for transformers based on on-load tap changers. Background Technology

[0002] A transformer converts electrical energy at one voltage level to another to meet the needs of different electrical equipment. It can increase voltage to enable long-distance power transmission and reduce line losses, or decrease voltage to provide suitable voltage for various electrical devices. It typically consists of a core, windings, insulating bushings, and an oil tank. The core is the magnetic circuit part of the transformer, the windings are the electrical circuit part, the insulating bushings are used to lead out the winding connections, and the oil tank is used to house the core and windings, and also serves to dissipate heat and provide protection.

[0003] On-load tap changers are connected to the transformer windings. By operating the on-load tap changer, the taps of the windings can be switched, thereby changing the transformer's turns ratio and achieving voltage regulation. During operation, voltage fluctuations in existing transformers may cause the transformer's output voltage to deviate from its rated value. Currently, in practical engineering applications, the capacity adjustment point of on-load tap changers is usually determined based on the experience of relevant technicians, which cannot accurately judge the fluctuating voltage. If the voltage fluctuations are frequent and large, the on-load tap changer may operate frequently, failing to accurately adjust the on-load tap changer to the optimal capacity adjustment point, which may lead to voltage regulation failure and increased voltage fluctuations. Summary of the Invention

[0004] The purpose of this invention is to provide a voltage monitoring method and system for transformers based on on-load tap changers, so as to solve the technical problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A voltage monitoring method for a transformer based on an on-load tap changer, comprising:

[0007] Acquire real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data;

[0008] The real-time power no-load loss value is obtained based on the real-time input voltage data and the real-time winding current data.

[0009] The real-time power load loss value is obtained based on the real-time winding temperature data and the load power factor.

[0010] The adjustment value of the on-load tap changer is obtained based on the real-time no-load power loss value and the real-time load power loss value, and the adjustment amplitude value of the on-load tap changer is obtained based on the adjustment value.

[0011] Determine whether the adjustment value is greater than the preset range;

[0012] If the value is greater than the value, the on-load tap changer reduces the output voltage, and the adjustment direction is determined to be the voltage reduction direction. The on-load tap changer is then adjusted to reduce the voltage based on the adjustment amplitude value.

[0013] If the value is less than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage increase direction, and voltage increase adjustment is performed based on the adjustment amplitude value.

[0014] Preferably, the step of obtaining the real-time power no-load loss value based on the real-time input voltage data and the real-time winding current data includes:

[0015] The magnetic flux density value is obtained based on real-time input voltage data and real-time winding current data.

[0016] Obtain the preset hysteresis coefficient of the transformer;

[0017] Obtain the preset frequency value of the AC power supply of the transformer;

[0018] The hysteresis loss is calculated based on the magnetic flux density, the transformer's preset hysteresis coefficient, and the preset frequency. The calculation formula is as follows:

[0019] P a =h a *k a *N 2 ;

[0020] Among them, P a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0021] Obtain the thickness value of the pre-set silicon steel sheet inside the transformer;

[0022] Obtain the density value of the pre-set silicon steel sheets inside the transformer;

[0023] Obtain the weight value of the preset iron core inside the transformer;

[0024] The eddy current loss of the transformer is calculated based on the thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency. The calculation formula is as follows:

[0025]

[0026] Among them, P b D represents the eddy current loss value of the transformer.r Here, d represents the preset density of the silicon steel sheet, d represents the preset thickness of the silicon steel sheet, G represents the preset weight of the iron core, and P represents the preset weight of the iron core. a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0027] The real-time no-load power loss is calculated based on the hysteresis loss and eddy current loss values. The calculation formula is as follows:

[0028] P0 = P a +P b ;

[0029] Wherein, P0 is the real-time power no-load loss value.

[0030] Preferably, the step of obtaining the magnetic flux density value based on real-time input voltage data and real-time winding current data includes:

[0031] Acquire real-time input voltage data;

[0032] Acquire real-time winding current data;

[0033] Obtain the effective cross-sectional area value of the preset iron core inside the transformer;

[0034] Obtain the average length of the preset magnetic circuit of the transformer core;

[0035] The magnetic flux density value is calculated based on real-time input voltage data, real-time winding current data, and effective cross-sectional area.

[0036]

[0037] Where N is the magnetic flux density value, U is the real-time input voltage data, I is the real-time winding current data, and k is the magnetic flux density value. a C is the preset frequency value, and A is the preset number of turns in the transformer winding. e To preset the effective cross-sectional area value of the iron core, l a The average length of the preset iron core magnetic circuit.

[0038] Preferably, the step of obtaining the load power factor based on real-time winding current data includes:

[0039] The effective voltage value is obtained based on real-time input voltage data;

[0040] The effective current value is obtained based on real-time winding current data;

[0041] The rated power under complex impedance is obtained based on the effective voltage and effective current values.

[0042] Real-time active power is obtained based on real-time input voltage data and real-time winding current data;

[0043] The cosine value of the phase difference is obtained based on the rated power of the complex impedance and the real-time active power.

[0044] Use the cosine value as the load power factor.

[0045] Preferably, the step of obtaining the real-time power load loss value based on the real-time winding temperature data and the load power factor includes:

[0046] Obtain real-time winding current data of the transformer;

[0047] Obtain real-time winding temperature data of the transformer;

[0048] Obtain the preset resistivity of the transformer winding;

[0049] Obtain the effective cross-sectional area value of the preset iron core inside the transformer;

[0050] Obtain the preset thermal conductivity of the preset iron core inside the transformer;

[0051] The real-time resistance value is obtained based on real-time winding current data, real-time winding temperature data, preset resistivity, and preset thermal conductivity. The calculation formula is as follows:

[0052]

[0053] Where R is the real-time resistance value, ρ is the preset resistivity, t is the real-time winding temperature data, and A e I represents the preset effective cross-sectional area of ​​the iron core, and I represents the real-time winding current data.

[0054] Obtain the preset load value of the transformer winding;

[0055] Obtain the load power factor;

[0056] Obtain the preset rated short-circuit loss value of the transformer winding;

[0057] The real-time power load loss value is calculated based on the preset load value, real-time resistance value, load power factor, and preset rated short-circuit loss value. The calculation formula is as follows:

[0058] P d =β 2 *R*K*O;

[0059] Among them, P d β is the real-time power load loss value, R is the preset load value, K is the preset rated short-circuit loss value, and O is the load power factor.

[0060] Preferably, the step of obtaining the adjustment value of the on-load tap-changing transformer from the real-time no-load power loss value and the real-time load power loss value includes:

[0061] Obtain real-time power no-load loss value;

[0062] Obtain real-time power load loss values;

[0063] Obtain the preset temperature correction factor;

[0064] Obtain real-time winding temperature data;

[0065] The adjustment value of the on-load tap-changing transformer is calculated based on the preset temperature correction coefficient, real-time winding temperature data, real-time no-load power loss value, and real-time load power loss value. The calculation formula is as follows:

[0066] P t =P0+P d *K t *t;

[0067] Among them, P t P0 is the adjustment value of the on-load tap-changing transformer, and P is the real-time no-load power loss value. d Here, t represents the real-time power load loss value, and t represents the real-time winding temperature data, in K. t This is the preset temperature correction factor.

[0068] Preferably, the step of obtaining the on-load tap changer adjustment amplitude value based on the adjustment value includes:

[0069] Obtain the adjustment value;

[0070] Obtain real-time power no-load loss value;

[0071] Obtain real-time power load loss values;

[0072] Obtain the preset power no-load loss value of the transformer;

[0073] Obtain the preset power load loss value of the transformer;

[0074] Obtain the rated capacity of the transformer;

[0075] The on-load tap changer adjustment range is calculated based on the adjustment value, real-time no-load power loss value, real-time load power loss value, preset no-load power loss value, preset load power loss value, and rated capacity. The calculation formula is as follows:

[0076]

[0077] Where S is the on-load tap changer adjustment amplitude value, P t P is the adjustment value for an on-load tap-changing transformer. dP0 is the real-time power load loss value, and F is the real-time no-load power loss value. d P represents the rated capacity of the transformer. A P is the preset power no-load loss value. B This is the preset power load loss value.

[0078] This invention also discloses a voltage monitoring system for a transformer based on an on-load tap changer, comprising:

[0079] The first acquisition module is used to acquire real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data.

[0080] The second acquisition module is used to acquire the real-time power no-load loss value based on the real-time input voltage data and the real-time winding current data.

[0081] The third acquisition module is used to acquire the load power factor based on real-time winding current data;

[0082] The fourth acquisition module is used to acquire the real-time power load loss value based on the real-time winding temperature data and the load power factor.

[0083] The fifth acquisition module is used to obtain the adjustment value of the on-load tap changer transformer based on the real-time no-load power loss value and the real-time load power loss value, and to obtain the adjustment amplitude value of the on-load tap changer based on the adjustment value.

[0084] The judgment module is used to determine whether the adjustment value is greater than the preset range;

[0085] If the value is greater than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage reduction direction, and voltage reduction adjustment is performed based on the adjustment amplitude value.

[0086] If the value is less than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage increase direction, and voltage increase adjustment is performed based on the adjustment amplitude value.

[0087] Preferably, the second acquisition module includes:

[0088] The first acquisition unit is used to acquire the magnetic flux density value based on real-time input voltage data and real-time winding current data.

[0089] The second acquisition unit is used to acquire the preset hysteresis coefficient of the transformer;

[0090] The third acquisition unit is used to acquire the preset frequency value of the AC power supply of the transformer;

[0091] The first calculation unit is used to calculate the hysteresis loss value based on the magnetic flux density value, the transformer's preset hysteresis coefficient, and the preset frequency value. The calculation formula is as follows:

[0092] Pa =h a *k a *N 2 ;

[0093] Among them, P a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0094] The fourth acquisition unit is used to acquire the thickness value of the preset silicon steel sheet inside the transformer;

[0095] The fifth acquisition unit is used to acquire the density value of the preset silicon steel sheets inside the transformer;

[0096] The sixth acquisition unit is used to acquire the weight value of the preset iron core inside the transformer;

[0097] The second calculation unit is used to calculate the eddy current loss of the transformer based on the thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency. The calculation formula is as follows:

[0098]

[0099] Among them, P b D represents the eddy current loss value of the transformer. r Here, d represents the preset density of the silicon steel sheet, d represents the preset thickness of the silicon steel sheet, G represents the preset weight of the iron core, and P represents the preset weight of the iron core. a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0100] The third calculation unit is used to calculate the real-time no-load power loss value based on the hysteresis loss value and the eddy current loss value. The calculation formula is as follows:

[0101] P0 = P a +P b ;

[0102] Wherein, P0 is the real-time power no-load loss value.

[0103] Preferably, the second acquisition module includes:

[0104] The seventh acquisition unit is used to acquire real-time input voltage data;

[0105] The eighth acquisition unit is used to acquire real-time winding current data;

[0106] The ninth acquisition unit is used to acquire the effective cross-sectional area value of the preset iron core inside the transformer;

[0107] The tenth acquisition unit is used to acquire the average length of the preset magnetic circuit of the iron core inside the transformer;

[0108] The fourth calculation unit is used to calculate the magnetic flux density value based on the real-time input voltage data, real-time winding current data, and effective cross-sectional area value.

[0109]

[0110] Where N is the magnetic flux density value, U is the real-time input voltage data, I is the real-time winding current data, and k is the magnetic flux density value. a C is the preset frequency value, and A is the preset number of turns in the transformer winding. e To preset the effective cross-sectional area value of the iron core, l a The average length of the preset iron core magnetic circuit.

[0111] The beneficial effects of this application are as follows: This invention can accurately calculate the real-time no-load power loss and real-time load power loss of the transformer by monitoring data such as winding temperature, input voltage, and winding current in real time. This allows for the determination of the adjustment value for the on-load tap changer and the adjustment range of the on-load tap changer. This precise calculation method ensures that the on-load tap changer can adjust in a timely and accurate manner to cope with voltage fluctuations, thereby ensuring that the transformer's output voltage remains stable near its rated value. This addresses the problem that transformer voltage regulation often relies on the experience and subjective judgment of technicians, making it difficult to accurately handle complex voltage fluctuations. This method, through automated data monitoring and calculation, reduces interference from human factors and improves the accuracy and reliability of the adjustment. In cases of frequent or large voltage fluctuations, traditional voltage regulation methods may cause the on-load tap changer to operate frequently or even fail to accurately adjust the voltage to the ideal state, thus exacerbating voltage fluctuations or leading to regulation failure. This method, through precise adjustment strategies and amplitude control, avoids such problems, ensuring voltage stability and safety. Attached Figure Description

[0112] Figure 1 This is a schematic diagram of a method flow according to an embodiment of this application.

[0113] Figure 2 This is a schematic diagram of the system structure according to an embodiment of this application.

[0114] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0115] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0116] like Figure 1As shown, this application provides a voltage monitoring method for a transformer based on an on-load tap changer, comprising:

[0117] S1. Obtain real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data;

[0118] S2. Obtain the real-time power no-load loss value based on the real-time input voltage data and real-time winding current data;

[0119] S3. Obtain the load power factor based on real-time winding current data;

[0120] S4. Obtain the real-time power load loss value based on the real-time winding temperature data and load power factor;

[0121] S5. Obtain the adjustment value of the on-load tap changer transformer based on the real-time no-load power loss value and the real-time load power loss value, and obtain the adjustment amplitude value of the on-load tap changer based on the adjustment value.

[0122] S6. Determine whether the adjustment value is greater than the preset range;

[0123] If the value is greater than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage reduction direction, and voltage reduction adjustment is performed based on the adjustment amplitude value.

[0124] If the value is less than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage increase direction, and voltage increase adjustment is performed based on the adjustment amplitude value.

[0125] As described in steps S1-S6 above, during transformer operation, the output voltage is prone to deviate from the rated value due to various factors such as power supply fluctuations. Existing voltage monitoring methods typically rely on the experience of technicians to set capacity adjustment points, which cannot accurately determine the amplitude and frequency of voltage fluctuations. This leads to frequent operation of the on-load tap changer when voltage fluctuations are frequent or large, failing to precisely adjust the voltage to the optimal state. Frequent voltage fluctuations and adjustments not only affect the stability of the power grid but may also accelerate the aging of transformers and their auxiliary equipment, reducing their service life. Secondly, the on-load tap changer also has certain limitations in the adjustment process. Due to the mechanical structure and electrical characteristics of the switch, its adjustment range and accuracy are limited. When voltage fluctuations exceed the switch's adjustment range, the on-load tap changer may not be able to effectively adjust, resulting in ineffective control of voltage fluctuations. These problems can further exacerbate voltage fluctuations and affect the stable operation of the power grid. This invention detects real-time input voltage and current data and combines them with internal transformer parameters (such as hysteresis coefficient, silicon steel sheet characteristics, core weight, etc.) to calculate the power loss of the transformer under no-load conditions. This is used to evaluate the transformer's energy efficiency and operating status, and dynamically adjusts the on-load tap changer based on the power loss value. This effectively reduces voltage fluctuations, ensures that the transformer's output voltage remains near the rated value, and improves power supply quality. Combining real-time winding temperature, current data, and parameters such as the transformer winding resistivity and effective core cross-sectional area, the invention calculates the power loss of the transformer under load conditions. The power loss under load conditions is used to evaluate the transformer's energy efficiency and heat generation during load operation. Based on the real-time no-load power loss value and the real-time load power loss value, combined with preset temperature correction coefficients and winding temperature data, the adjustment value of the on-load tap changer is calculated. Then, based on the adjustment value, real-time power loss value, preset power loss value, and rated capacity, the adjustment range of the on-load tap changer is calculated. Adjusting the on-load tap changer based on this range accurately regulates the transformer's output voltage, ensuring voltage stability. This improves power quality and reduces the impact of voltage fluctuations on electrical equipment. In practical applications, it can be widely used in various situations requiring stable voltage, such as industrial production, commercial power supply, and residential applications. It helps improve equipment operating efficiency and reliability, and extends equipment lifespan.

[0126] In one embodiment, the step of obtaining the real-time power no-load loss value based on the real-time input voltage data and the real-time winding current data includes:

[0127] S201. Obtain the magnetic flux density value based on real-time input voltage data and real-time winding current data;

[0128] S202, Obtain the preset hysteresis coefficient of the transformer;

[0129] S203. Obtain the preset frequency value of the AC power supply of the transformer;

[0130] S204. Calculate the hysteresis loss value based on the magnetic flux density value, the transformer's preset hysteresis coefficient, and the preset frequency value. The calculation formula is as follows:

[0131] P a =h a *k a *N 2 ;

[0132] Among them, P a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0133] S205. Obtain the thickness value of the preset silicon steel sheet inside the transformer;

[0134] S206. Obtain the density value of the preset silicon steel sheet inside the transformer;

[0135] S207. Obtain the weight value of the preset iron core inside the transformer;

[0136] S208. Calculate the eddy current loss of the transformer based on the thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency. The calculation formula is as follows:

[0137]

[0138] Among them, P b D represents the eddy current loss value of the transformer. r Here, d represents the preset density of the silicon steel sheet, d represents the preset thickness of the silicon steel sheet, G represents the preset weight of the iron core, and P represents the preset weight of the iron core. a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0139] S209. Calculate the real-time power no-load loss value based on the hysteresis loss value and the eddy current loss value. The calculation formula is as follows:

[0140] P0 = P a +P b ;

[0141] Wherein, P0 is the real-time power no-load loss value.

[0142] As described in steps S201-S209 above, this invention obtains the magnetic flux density value by real-time monitoring of the input voltage and winding current. The magnetic flux density value is the basis for calculating no-load loss, and an accurate magnetic flux density value can improve the accuracy of subsequent calculations. Then, by obtaining the transformer's preset hysteresis coefficient, which is an important parameter reflecting the transformer's hysteresis characteristics, obtaining this coefficient allows for more accurate calculation of hysteresis loss, ensuring that the calculated hysteresis loss matches the actual characteristics of the transformer. This avoids deviations in hysteresis loss calculation caused by inaccurate hysteresis coefficients, thus improving the accuracy of hysteresis loss calculation. Simultaneously, the frequency value affects both hysteresis loss and eddy current loss; obtaining an accurate frequency value is crucial. The preset frequency value allows loss calculations to better reflect actual operating conditions, improving accuracy and resolving errors caused by frequency uncertainty. This ensures the loss calculations reflect the transformer's losses at the actual frequency. Then, based on the magnetic flux density, the transformer's preset hysteresis coefficient, and the preset frequency value, the hysteresis loss value is calculated. This formula accurately calculates the hysteresis loss value, providing a crucial component for evaluating the transformer's no-load loss. It helps optimize transformer performance and efficiency, avoiding the impact of inaccurate hysteresis loss calculations on no-load loss assessment. Therefore, it provides a basis for the optimized design and operation of transformers. Assuming a transformer's preset hysteresis coefficient h... a =1.6, preset frequency value k a =50Hz, the measured magnetic flux density value N = 1.2 Tesla, then according to P a =h a *k a *N 2 Calculate the hysteresis loss value.

[0143] P a = 1.6 * 50 * 1.2 2 ;

[0144] P a =1.6 * 50 * 1.44;

[0145] P a =115.2;

[0146] Accurate calculation of hysteresis loss allows for a better assessment of transformer energy loss, helping to ensure efficient operation under different load conditions and addressing the issue of inaccurate hysteresis loss calculations caused by existing monitoring methods that may not consider all relevant parameters. Then, based on thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency, the transformer's eddy current loss is calculated. Eddy current loss is also a significant component of transformer no-load loss; accurate calculation of eddy current loss improves the overall loss calculation accuracy and avoids the inaccuracy of no-load loss calculations that may be caused by existing monitoring methods ignoring the impact of eddy current loss. Assuming a transformer has a preset silicon steel sheet thickness d = 0.5 mm and a density D... r =7.65 g / cm³, preset core weight G = 10 kg, transformer magnetic flux density N = 1.5 tesla, preset hysteresis coefficient h a =2.5, preset frequency value k a =50 Hz, substitute these values ​​into the calculation formula:

[0147]

[0148] P b ≈200.17;

[0149] By comprehensively considering multiple factors such as the thickness and density of silicon steel sheets, the weight of the iron core, magnetic flux density, preset hysteresis coefficient, and preset frequency, the eddy current loss value of the transformer can be calculated relatively accurately. This calculation helps to comprehensively assess the transformer's losses, providing important reference for its design, operation, and maintenance. Finally, by adding the hysteresis loss value and the eddy current loss value, the real-time no-load power loss value can be obtained. This value accurately reflects the no-load loss of the transformer in actual operation, providing important parameters for transformer monitoring and management, making the no-load loss assessment of the transformer more accurate, helping to promptly identify potential problems, and thus comprehensively understanding the power loss of the transformer under no-load conditions.

[0150] In one embodiment, the step of obtaining the magnetic flux density value based on real-time input voltage data and real-time winding current data includes:

[0151] S2011, Obtain real-time input voltage data;

[0152] S2012, Obtain real-time winding current data;

[0153] S2013. Obtain the effective cross-sectional area value of the preset iron core inside the transformer;

[0154] S2014. Obtain the average length of the preset magnetic circuit of the transformer core.

[0155] S2015. Calculate the magnetic flux density value based on real-time input voltage data, real-time winding current data, and effective cross-sectional area value, where the calculation formula is:

[0156]

[0157] Where N is the magnetic flux density value, U is the real-time input voltage data, I is the real-time winding current data, and k is the magnetic flux density value. a C is the preset frequency value, and A is the preset number of turns in the transformer winding. e To preset the effective cross-sectional area value of the iron core, l a The average length of the preset iron core magnetic circuit.

[0158] As described in steps S2011-S2015 above, this invention, by acquiring real-time input voltage data and real-time winding current data, can more accurately reflect the electromagnetic state inside the transformer, providing basic data for subsequent calculation of magnetic flux density values. This solves the problem of magnetic flux density calculation errors caused by inaccurate input voltage and winding current data, ensuring the accuracy of the magnetic flux density value. Furthermore, by acquiring the effective cross-sectional area value and the average length of the preset core magnetic circuit inside the transformer, these parameters are used to accurately calculate the magnetic flux density value, making the calculation results more consistent with the actual physical characteristics of the transformer. This avoids magnetic flux density calculation deviations caused by unclear core parameters (effective cross-sectional area and average length of magnetic circuit), making the calculation results more reflective of the actual situation of the transformer. Based on the formula for calculating the magnetic flux density value using real-time input voltage data, real-time winding current data, and effective cross-sectional area value, the magnetic flux density value can be accurately calculated, providing accurate input parameters for subsequent calculations of hysteresis loss and eddy current loss. Assuming a transformer has a real-time input voltage data U = 220V, a real-time winding current data I = 5A, and a preset frequency value k... a =50Hz, preset number of turns of transformer winding C=100, preset effective cross-sectional area of ​​iron core A e =0.01m 2 The average length l of the preset iron core magnetic circuit a = 0.5m. According to the calculation formula:

[0159]

[0160] N = 10.22;

[0161] Using given parameters such as real-time input voltage data, real-time winding current data, and effective cross-sectional area, the magnetic flux density value is calculated to be 10.22 Tesla. This magnetic flux density value can be used for subsequent calculations of hysteresis loss and eddy current loss to evaluate the transformer's performance and losses.

[0162] In one embodiment, the step of obtaining the load power factor based on real-time winding current data includes:

[0163] S301. Obtain the effective voltage value based on real-time input voltage data;

[0164] S302. Obtain the effective current value based on real-time winding current data;

[0165] S303. Obtain the rated power under complex impedance based on the effective voltage and effective current values;

[0166] S304. Obtain real-time active power based on real-time input voltage data and real-time winding current data;

[0167] S305. Obtain the cosine value of the phase difference based on the rated power of the complex impedance and the real-time active power.

[0168] S306. Use the cosine value as the load power factor.

[0169] As described in steps S301-S406 above, this invention obtains the effective voltage value by real-time input voltage data and the effective current value by real-time winding current data, comprehensively considering the voltage and current conditions during transformer operation. Then, it obtains the complex impedance rated power based on the effective voltage and current values, and the real-time active power based on the real-time input voltage and winding current data. Finally, it obtains the cosine value of the phase difference as the load power factor. This accurately determines the load power factor, more accurately assesses the transformer's load characteristics, and avoids the possibility that the determination of the load power factor might rely on experience or simple estimation, which can lead to significant subjectivity and error. Through the above steps, specific calculations are performed based on real-time data, avoiding errors caused by subjective judgment, making the determination of the load power factor more scientific and accurate. In actual transformer operation, voltage and current may change, and load conditions are complex. The above steps enable dynamic calculation based on real-time data, better adapting to complex operating conditions, accurately reflecting the load power factor of the transformer at different times, improving the accuracy of voltage monitoring, promptly detecting voltage anomalies and making adjustments, and ensuring the stable operation of the transformer.

[0170] In one embodiment, the step of obtaining the real-time power load loss value based on the real-time winding temperature data and the load power factor includes:

[0171] S401. Obtain real-time winding current data of the transformer;

[0172] S402. Obtain real-time winding temperature data of the transformer;

[0173] S403. Obtain the preset resistivity of the transformer winding;

[0174] S404. Obtain the effective cross-sectional area value of the preset iron core inside the transformer;

[0175] S405. Obtain the preset thermal conductivity of the preset iron core inside the transformer;

[0176] S406. Obtain the real-time resistance value based on real-time winding current data, real-time winding temperature data, preset resistivity, and preset thermal conductivity. The calculation formula is as follows:

[0177]

[0178] Where R is the real-time resistance value, ρ is the preset resistivity, t is the real-time winding temperature data, and A e I represents the preset effective cross-sectional area of ​​the iron core, and I represents the real-time winding current data.

[0179] S407. Obtain the preset load value of the transformer winding;

[0180] S408. Obtain the preset rated short-circuit loss value of the transformer winding;

[0181] S409. Calculate the real-time power load loss value based on the preset load value, real-time resistance value, load power factor, and preset rated short-circuit loss value. The calculation formula is as follows:

[0182] P d =β 2 *R*K*O;

[0183] Among them, P d β is the real-time power load loss value, R is the preset load value, K is the preset rated short-circuit loss value, and O is the load power factor.

[0184] As described in steps S401-S409 above, this invention, by acquiring real-time winding current data, real-time winding temperature data, and related preset parameters of the transformer, can comprehensively understand the transformer's operating status, enabling accurate calculation of real-time resistance and power load loss values. Then, based on the real-time winding current data, real-time winding temperature data, preset resistivity, and preset thermal conductivity, a calculation formula for the real-time resistance value is obtained, allowing for precise calculation of the real-time resistance value. This considers the influence of temperature on resistance, solving the problem of inaccurate resistance calculations caused by ignoring the effect of temperature. By considering real-time winding temperature data and preset thermal conductivity, the calculation of the real-time resistance value is more consistent with actual conditions, making the resistance value calculation more accurate. For example, assuming a transformer's preset resistivity is 0.0175 ohm·mm². 2 / meter, preset thermal conductivity is 40 W / (m·Kelvin), real-time winding temperature is 80℃, preset effective cross-sectional area of ​​core is 50 square millimeters, real-time winding current is 10 Amperes, according to the calculation formula:

[0185]

[0186] R = 0.48;

[0187] Using given real-time winding current data, real-time winding temperature data, preset resistivity, and preset thermal conductivity, the real-time resistance value is calculated to be 0.48 ohms using a calculation formula. This real-time resistance value can be used to calculate subsequent real-time power load losses.

[0188] Then, by obtaining the preset load value and preset rated short-circuit loss value of the transformer winding, the calculation error caused by using inaccurate preset parameters (such as resistivity, thermal conductivity, etc.) is avoided. By accurately obtaining these parameters, the calculation accuracy of real-time resistance value and real-time power load loss value is improved, and the problem of relying solely on experience or inaccurate data when evaluating transformer load loss is solved. The calculation is performed by obtaining real-time data and accurate preset parameters, and the real-time power load loss value is calculated based on these parameters and the real-time resistance value. For example, the preset load value of the transformer winding is 0.8 ohms, the real-time resistance value is 0.48 ohms, and the preset rated short-circuit loss value is 1000 watts.

[0189] R = 0.8 2 *0.48*1000;

[0190] R = 307.2;

[0191] By using preset load values, real-time resistance values, and preset rated short-circuit loss values, the real-time power load loss value is calculated to be 307.2 watts using a calculation formula. This real-time power load loss value can reflect the load loss of the transformer under the current operating conditions, and can accurately assess the load loss of the transformer in actual operation. If the resistance value rises abnormally or the load loss is too large, corresponding measures can be taken for adjustment and maintenance to improve the operating efficiency and reliability of the transformer.

[0192] In one embodiment, the step of obtaining the adjustment value of the on-load tap-changing transformer from the real-time no-load power loss value and the real-time load power loss value includes:

[0193] S501, Obtain the real-time power no-load loss value;

[0194] S502, Obtain real-time power load loss value;

[0195] S503, Obtain the preset temperature correction coefficient;

[0196] S504, Obtain real-time winding temperature data;

[0197] S505. Calculate the adjustment value of the on-load tap-changing transformer based on the preset temperature correction coefficient, real-time winding temperature data, real-time no-load power loss value, and real-time load power loss value. The calculation formula is as follows:

[0198] P t =P0+P d *K t *t;

[0199] Among them, P t P0 is the adjustment value of the on-load tap-changing transformer, and P is the real-time no-load power loss value. d Here, t represents the real-time power load loss value, and t represents the real-time winding temperature data, in K. t This is the preset temperature correction factor.

[0200] As described in steps S501-S505 above, this invention, through multiple factors such as real-time no-load power loss value, real-time load power loss value, preset temperature correction coefficient, and real-time winding temperature data, can more accurately calculate the adjustment value of the on-load tap-changing transformer, thereby achieving precise adjustment of the transformer output voltage. Let's assume the preset temperature correction coefficient K... t =0.01, real-time no-load power loss value P0 = 100W, real-time load power loss value P d =200W, real-time winding temperature data t=50℃, based on P0+P d *K t *t calculation, P t =200. This formula comprehensively considers multiple factors such as real-time no-load power loss, real-time load power loss, preset temperature correction coefficient, and real-time winding temperature data, to more accurately calculate the adjustment value of the on-load tap-changing transformer. This achieves precise regulation of the transformer's output voltage, solving the inaccuracy problem of relying on a single factor for transformer regulation. The comprehensive calculation of multiple factors can more fully reflect the actual operating status of the transformer. By introducing a preset temperature correction coefficient, the influence of temperature on transformer performance can be considered, making the adjustment value more consistent with the actual operating conditions, improving the stability and reliability of the transformer. For situations with frequent and large voltage fluctuations, it can be adjusted more accurately, avoiding problems such as voltage regulation failure and aggravated voltage fluctuations caused by improper adjustment.

[0201] In one embodiment, the step of obtaining the on-load tap changer adjustment amplitude value based on the adjustment value includes:

[0202] S506, Obtain the adjustment value;

[0203] S507, Obtain real-time power no-load loss value;

[0204] S508, Obtain real-time power load loss value;

[0205] S509. Obtain the preset power no-load loss value of the transformer;

[0206] S510. Obtain the preset power load loss value of the transformer;

[0207] S511. Obtain the rated capacity of the transformer;

[0208] S512. Calculate the on-load tap changer adjustment range based on the adjustment value, real-time no-load power loss value, real-time load power loss value, preset no-load power loss value, preset load power loss value, and rated capacity. The calculation formula is as follows:

[0209]

[0210] Where S is the on-load tap changer adjustment amplitude value, P t P is the adjustment value for an on-load tap-changing transformer. d P0 is the real-time power load loss value, and F is the real-time no-load power loss value. d P represents the rated capacity of the transformer. A P is the preset power no-load loss value. B This is the preset power load loss value.

[0211] As described in steps S506-S512 above, this invention comprehensively considers various operating states and performance indicators of the transformer by acquiring multiple parameters such as the adjustment value, real-time no-load power loss value, real-time load power loss value, preset no-load power loss value, preset load power loss value, and rated capacity. This allows for more accurate calculation of the on-load tap changer adjustment amplitude, avoiding the inaccuracies caused by relying solely on the experience of technical personnel to determine the capacity adjustment point of the on-load tap-changing transformer. It enables precise calculation and adjustment based on actual data, and by comprehensively considering multiple factors, the adjustment of the on-load tap changer becomes more precise and better adapts to the actual operating conditions of the transformer, thereby more effectively ensuring the stability of the transformer's output voltage. For situations with frequent and large voltage fluctuations, the adjustment amplitude of the on-load tap changer can be accurately calculated. Assuming the adjustment value P... t =300, real-time power load loss value P d =150, real-time power no-load loss value P0=50, transformer preset power no-load loss value P A =40, preset power load loss value P B =120, the rated capacity F of the transformer d =1000, according to the formula Calculate S≈265. Through this example, based on the given parameters, the on-load tap changer adjustment range can be calculated using the formula, enabling more accurate adjustment and avoiding problems such as tap changer failure and increased voltage fluctuations caused by frequent operation.

[0212] like Figure 2 As shown, the present invention also provides a voltage monitoring system for a transformer based on an on-load tap changer, comprising:

[0213] The first acquisition module 1 is used to acquire real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data.

[0214] The second acquisition module 2 is used to acquire the real-time power no-load loss value based on the real-time input voltage data and the real-time winding current data.

[0215] The third acquisition module 3 is used to acquire the load power factor based on real-time winding current data;

[0216] The fourth acquisition module 4 is used to acquire the real-time power load loss value based on the real-time winding temperature data and the load power factor.

[0217] The fifth acquisition module 5 is used to obtain the adjustment value of the on-load tap changer based on the real-time no-load power loss value and the real-time load power loss value, and to obtain the adjustment amplitude value of the on-load tap changer based on the adjustment value.

[0218] Module 6 is used to determine whether the adjustment value is greater than the preset range;

[0219] If the value is greater than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage reduction direction, and voltage reduction adjustment is performed based on the adjustment amplitude value.

[0220] If the value is less than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage increase direction, and voltage increase adjustment is performed based on the adjustment amplitude value.

[0221] In one embodiment, the second acquisition module 2 includes:

[0222] The first acquisition unit is used to acquire the magnetic flux density value based on real-time input voltage data and real-time winding current data.

[0223] The second acquisition unit is used to acquire the preset hysteresis coefficient of the transformer;

[0224] The third acquisition unit is used to acquire the preset frequency value of the AC power supply of the transformer;

[0225] The first calculation unit is used to calculate the hysteresis loss value based on the magnetic flux density value, the transformer's preset hysteresis coefficient, and the preset frequency value. The calculation formula is as follows:

[0226] P a =h a *k a *N 2 ;

[0227] Among them, P a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0228] The fourth acquisition unit is used to acquire the thickness value of the preset silicon steel sheet inside the transformer;

[0229] The fifth acquisition unit is used to acquire the density value of the preset silicon steel sheets inside the transformer;

[0230] The sixth acquisition unit is used to acquire the weight value of the preset iron core inside the transformer;

[0231] The second calculation unit is used to calculate the eddy current loss of the transformer based on the thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency. The calculation formula is as follows:

[0232]

[0233] Among them, P b D represents the eddy current loss value of the transformer. r Here, d represents the preset density of the silicon steel sheet, d represents the preset thickness of the silicon steel sheet, G represents the preset weight of the iron core, and P represents the preset weight of the iron core. a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value;

[0234] The third calculation unit is used to calculate the real-time no-load power loss value based on the hysteresis loss value and the eddy current loss value. The calculation formula is as follows:

[0235] P0 = P a +P b ;

[0236] Wherein, P0 is the real-time power no-load loss value.

[0237] In one embodiment, the second acquisition module 2 includes:

[0238] The seventh acquisition unit is used to acquire real-time input voltage data;

[0239] The eighth acquisition unit is used to acquire real-time winding current data;

[0240] The ninth acquisition unit is used to acquire the effective cross-sectional area value of the preset iron core inside the transformer;

[0241] The tenth acquisition unit is used to acquire the average length of the preset magnetic circuit of the iron core inside the transformer;

[0242] The fourth calculation unit is used to calculate the magnetic flux density value based on the real-time input voltage data, real-time winding current data, and effective cross-sectional area value.

[0243]

[0244] Where N is the magnetic flux density value, U is the real-time input voltage data, I is the real-time winding current data, and k is the magnetic flux density value. a C is the preset frequency value, and A is the preset number of turns in the transformer winding. e To preset the effective cross-sectional area value of the iron core, l a The average length of the preset iron core magnetic circuit.

[0245] 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. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media provided in this application and in the embodiments may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual-speed SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0246] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, apparatus, article, or method that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, apparatus, article, or method. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, apparatus, article, or method that includes that element.

[0247] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent results or equivalent process transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A voltage monitoring method for a transformer based on an on-load tap changer, characterized in that, include: Acquire real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data; The magnetic flux density value is obtained based on real-time input voltage data and real-time winding current data. Obtain the preset hysteresis coefficient of the transformer; Obtain the preset frequency value of the AC power supply of the transformer; The hysteresis loss is calculated based on the magnetic flux density, the transformer's preset hysteresis coefficient, and the preset frequency. The calculation formula is as follows: ； Among them, P a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value; Obtain the thickness value of the pre-set silicon steel sheet inside the transformer; Obtain the density value of the pre-set silicon steel sheets inside the transformer; Obtain the weight value of the preset iron core inside the transformer; The eddy current loss of the transformer is calculated based on the thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency. The calculation formula is as follows: ； Among them, P b D represents the eddy current loss value of the transformer. r Here, d represents the preset density of the silicon steel sheet, d represents the preset thickness of the silicon steel sheet, G represents the preset weight of the iron core, and h represents the preset weight of the iron core. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value; The real-time no-load power loss is calculated based on the hysteresis loss and eddy current loss values. The calculation formula is as follows: P0=P a +P b ; Wherein, P0 is the real-time power no-load loss value; The load power factor is obtained based on real-time winding current data; Obtain real-time winding current data of the transformer; Obtain real-time winding temperature data of the transformer; Obtain the preset resistivity of the transformer winding; Obtain the effective cross-sectional area value of the preset iron core inside the transformer; Obtain the preset thermal conductivity of the preset iron core inside the transformer; The real-time resistance value is obtained based on real-time winding current data, real-time winding temperature data, preset resistivity, and effective cross-sectional area. The calculation formula is as follows: ； Where R is the real-time resistance value, ρ is the preset resistivity, t is the real-time winding temperature data, and A e I represents the preset effective cross-sectional area of ​​the iron core, and I represents the real-time winding current data. Obtain the preset load value of the transformer winding; Obtain the load power factor; Obtain the preset rated short-circuit loss value of the transformer winding; The real-time power load loss value is calculated based on the preset load value, real-time resistance value, load power factor, and preset rated short-circuit loss value. The calculation formula is as follows: ； Among them, P d β is the real-time power load loss value, R is the preset load value, K is the real-time resistance value, O is the preset rated short-circuit loss value, and O is the load power factor. The adjustment value of the on-load tap changer is obtained based on the real-time no-load power loss value and the real-time load power loss value, and the adjustment amplitude value of the on-load tap changer is obtained based on the adjustment value. Determine whether the adjustment value is greater than the preset range; If the value is greater than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage reduction direction, and voltage reduction adjustment is performed based on the adjustment amplitude value. If the value is less than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage increase direction, and voltage increase adjustment is performed based on the adjustment amplitude value.

2. The voltage monitoring method for a transformer based on an on-load tap changer according to claim 1, characterized in that, The step of obtaining the magnetic flux density value based on real-time input voltage data and real-time winding current data includes: Acquire real-time input voltage data; Acquire real-time winding current data; Obtain the effective cross-sectional area value of the preset iron core inside the transformer; Obtain the average length of the preset magnetic circuit of the transformer core; The magnetic flux density value is calculated based on real-time input voltage data, real-time winding current data, and effective cross-sectional area value. The calculation formula is as follows: ； Where N is the magnetic flux density value, U is the real-time input voltage data, I is the real-time winding current data, and k is the magnetic flux density value. a C is the preset frequency value, and A is the preset number of turns in the transformer winding. e To preset the effective cross-sectional area value of the iron core, l a The average length of the preset iron core magnetic circuit.

3. The voltage monitoring method for a transformer based on an on-load tap changer according to claim 1, characterized in that, The step of obtaining the load power factor based on real-time winding current data includes: The effective voltage value is obtained based on real-time input voltage data; The effective current value is obtained based on real-time winding current data; The rated power under complex impedance is obtained based on the effective voltage and effective current values. Real-time active power is obtained based on real-time input voltage data and real-time winding current data; The cosine value of the phase difference is obtained based on the rated power of the complex impedance and the real-time active power. Use the cosine value as the load power factor.

4. The voltage monitoring method for a transformer based on an on-load tap changer according to claim 1, characterized in that, The steps for obtaining the adjustment value of the on-load tap-changing transformer from the real-time power no-load loss value and the real-time power load loss value include: Obtain real-time power no-load loss value; Obtain real-time power load loss values; Obtain the preset temperature correction factor; Obtain real-time winding temperature data; The adjustment value of the on-load tap-changing transformer is calculated based on the preset temperature correction coefficient, real-time winding temperature data, real-time no-load power loss value, and real-time load power loss value. The calculation formula is as follows: ； Among them, P t P0 is the adjustment value of the on-load tap-changing transformer, and P is the real-time no-load power loss value. d Here, t represents the real-time power load loss value, and t represents the real-time winding temperature data, in K. t This is the preset temperature correction factor.

5. The voltage monitoring method for a transformer based on an on-load tap changer according to claim 1, characterized in that, The step of obtaining the on-load tap changer adjustment amplitude value based on the adjustment value includes: Obtain the adjustment value; Obtain real-time power no-load loss value; Obtain real-time power load loss values; Obtain the preset power no-load loss value of the transformer; Obtain the preset power load loss value of the transformer; Obtain the rated capacity of the transformer; The on-load tap changer adjustment range is calculated based on the adjustment value, real-time no-load power loss value, real-time load power loss value, preset no-load power loss value, preset load power loss value, and rated capacity. The calculation formula is as follows: ； Where S is the on-load tap changer adjustment amplitude value, P t P is the adjustment value for an on-load tap-changing transformer. d P0 is the real-time power load loss value, and F is the real-time no-load power loss value. d P represents the rated capacity of the transformer. A P is the preset power no-load loss value. B This is the preset power load loss value.

6. A voltage monitoring system for a transformer based on an on-load tap changer, characterized in that, include: The first acquisition module is used to acquire real-time monitoring data of the transformer, including real-time winding temperature data, real-time input voltage data, and real-time winding current data. The second acquisition module is used to acquire the magnetic flux density value based on real-time input voltage data and real-time winding current data. Obtain the preset hysteresis coefficient of the transformer; Obtain the preset frequency value of the AC power supply of the transformer; The hysteresis loss is calculated based on the magnetic flux density, the transformer's preset hysteresis coefficient, and the preset frequency. The calculation formula is as follows: ； Among them, P a h is the hysteresis loss value. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value; Obtain the thickness value of the pre-set silicon steel sheet inside the transformer; Obtain the density value of the pre-set silicon steel sheets inside the transformer; Obtain the weight value of the preset iron core inside the transformer; The eddy current loss of the transformer is calculated based on the thickness, density, weight, magnetic flux density, preset hysteresis coefficient, and preset frequency. The calculation formula is as follows: ； Among them, P b D represents the eddy current loss value of the transformer. r Here, d represents the preset density of the silicon steel sheet, d represents the preset thickness of the silicon steel sheet, G represents the preset weight of the iron core, and h represents the preset weight of the iron core. a A preset hysteresis coefficient, k, is given for the transformer. a Where N is the preset frequency value and N is the magnetic flux density value; The real-time no-load power loss is calculated based on the hysteresis loss and eddy current loss values. The calculation formula is as follows: P0=P a +P b ; Wherein, P0 is the real-time power no-load loss value; The third acquisition module is used to acquire the load power factor based on real-time winding current data; The fourth acquisition module is used to acquire real-time winding current data of the transformer; Obtain real-time winding temperature data of the transformer; Obtain the preset resistivity of the transformer winding; Obtain the effective cross-sectional area value of the preset iron core inside the transformer; Obtain the preset thermal conductivity of the preset iron core inside the transformer; The real-time resistance value is obtained based on real-time winding current data, real-time winding temperature data, preset resistivity, and effective cross-sectional area. The calculation formula is as follows: ； Where R is the real-time resistance value, ρ is the preset resistivity, t is the real-time winding temperature data, and A e I represents the preset effective cross-sectional area of ​​the iron core, and I represents the real-time winding current data. Obtain the preset load value of the transformer winding; Obtain the load power factor; Obtain the preset rated short-circuit loss value of the transformer winding; The real-time power load loss value is calculated based on the preset load value, real-time resistance value, load power factor, and preset rated short-circuit loss value. The calculation formula is as follows: ； Among them, P d β is the real-time power load loss value, R is the preset load value, K is the real-time resistance value, O is the preset rated short-circuit loss value, and O is the load power factor. The fifth acquisition module is used to obtain the adjustment value of the on-load tap changer transformer based on the real-time no-load power loss value and the real-time load power loss value, and to obtain the adjustment amplitude value of the on-load tap changer based on the adjustment value. The judgment module is used to determine whether the adjustment value is greater than the preset range; If the value is greater than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage reduction direction, and voltage reduction adjustment is performed based on the adjustment amplitude value. If the value is less than the specified value, the adjustment direction of the on-load tap changer is determined to be the voltage increase direction, and voltage increase adjustment is performed based on the adjustment amplitude value.

7. A voltage monitoring system for a transformer based on an on-load tap changer according to claim 6, characterized in that, The second acquisition module includes: The seventh acquisition unit is used to acquire real-time input voltage data; The eighth acquisition unit is used to acquire real-time winding current data; The ninth acquisition unit is used to acquire the effective cross-sectional area value of the preset iron core inside the transformer; The tenth acquisition unit is used to acquire the average length of the preset magnetic circuit of the iron core inside the transformer; The fourth calculation unit is used to calculate the magnetic flux density value based on real-time input voltage data, real-time winding current data, and effective cross-sectional area value. The calculation formula is as follows: ； Where N is the magnetic flux density value, U is the real-time input voltage data, I is the real-time winding current data, and k is the magnetic flux density value. a C is the preset frequency value, and A is the preset number of turns in the transformer winding. e To preset the effective cross-sectional area value of the iron core, l a The average length of the preset iron core magnetic circuit.

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