Method and device for determining a model of a voltage transformer

Abstract

The application discloses a kind of voltage transformer model determination method and device.Therein, the method includes: based on the measurement voltage effective value data and active power data, using first point-by-point recursion method to determine the nonlinear resistance data of voltage transformer in preset sampling period, and determine the first relationship curve between nonlinear resistance data and resistance current peak value data;Based on resistance current peak value data, current effective value data and magnetic flux data are measured, and the second point-by-point recursion method is used to determine the nonlinear inductance data of voltage transformer in preset sampling period, and the second relationship curve between nonlinear inductance data and inductance current peak value data is determined;Model simulation processing is carried out according to the first relationship curve and the second relationship curve, and the voltage transformer model is obtained.The application solves the technical problems of low model construction accuracy and poor simulation effect caused by the fact that the voltage transformer model in the related art cannot accurately reflect the actual voltage transformer characteristics.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ferroresonance overvoltage of power system, in particular to a method and device for determining a model of voltage transformer. BACKGROUND

[0002] In the research of ferroresonance overvoltage of distribution system and the fuse blowing process of voltage transformer, the most common method is to analyze the cause of failure and study the corresponding resonance elimination measures by simulation modeling. The system model established by combining the actual situation of device parameters and wiring is the basis of the research, and the most critical is the establishment of the model of voltage transformer. The accuracy of the model of voltage transformer directly affects the accuracy of the simulation results. Since the voltage transformer is approximately unloaded in normal operation, the current simulation usually equivalent single-phase voltage transformer to a nonlinear inductor and a resistor in series, and uses the peak flux-current curve to represent its nonlinearity. However, in fact, the core has hysteresis loss and eddy current loss, which shows active property. The commonly used model cannot well reflect the actual characteristics of the voltage transformer, and the accuracy of the model of voltage transformer is poor, which further leads to the deviation of the model simulation test from the actual situation.

[0003] In view of the above problems, no effective solution has been proposed so far. SUMMARY

[0004] The embodiments of the present application provide a method and device for determining a model of voltage transformer, to at least solve the technical problem of low accuracy of model construction and poor simulation effect caused by the model of voltage transformer in the related art.

[0005] According to an aspect of the embodiments of the present application, a method for determining a voltage transformer model is provided, including: obtaining measured voltage effective value data, measured current effective value data, magnetic flux data and no-load loss curve of a voltage transformer in a preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operation state; determining non-linear resistance data of the voltage transformer in the preset sampling period based on the measured voltage effective value data and the active power data by using a first point-by-point recursive method; determining resistance current peak value data of the voltage transformer in the preset sampling period based on the non-linear resistance data, and a first relationship curve between the non-linear resistance data and the resistance current peak value data; determining non-linear inductance data of the voltage transformer in the preset sampling period based on the resistance current peak value data, the measured current effective value data and the magnetic flux data by using a second point-by-point recursive method; determining inductance current peak value data of the voltage transformer in the preset sampling period based on the non-linear inductance data, and a second relationship curve between the non-linear inductance data and the inductance current peak value data; and performing model simulation processing according to the first relationship curve and the second relationship curve to obtain the voltage transformer model.

[0006] Optionally, in the case that the measured voltage effective value data includes measured voltage effective values of the voltage transformer in a plurality of sampling segments in the preset sampling period, and the active power data includes active powers corresponding to the plurality of sampling segments, the determination of the non-linear resistance data of the voltage transformer in the preset sampling period based on the measured voltage effective value data and the active power data by using the first point-by-point recursive method includes: determining the non-linear resistance data by using the first point-by-point recursive method based on the measured voltage effective values and the active powers corresponding to the plurality of sampling segments, wherein the non-linear resistance data includes resistance values corresponding to the plurality of sampling segments.

[0007]

[0008] wherein, P k represents the active power corresponding to the kth sampling segment in the plurality of sampling segments, represents the voltage peak value corresponding to the kth sampling segment, U RMSk represents the measured voltage effective value corresponding to the kth sampling segment, θ k represents the phase angle corresponding to the kth sampling segment, R k represents the resistance value corresponding to the kth sampling segment.

[0009] Optionally, the first relationship curve between the nonlinear resistance data and the resistance current peak value data of the voltage transformer in the preset sampling period is determined based on the nonlinear resistance data, and the resistance current peak value data of the voltage transformer in the preset sampling period, and the first relationship curve comprises: determining the resistance current peak value data based on the resistance values of the plurality of sampling segments, wherein the resistance current peak value data comprises resistance current peak values corresponding to the plurality of sampling segments, by the following method:

[0010]

[0011] wherein, i Rk represents the resistance current peak value corresponding to the kth sampling segment, i R(k-1) represents the resistance current peak value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, U k(m-1) represents the voltage peak value corresponding to the (k-1)th sampling segment, P1 represents the active power corresponding to the first sampling segment in the plurality of sampling segments, U RMS1 represents the measured voltage effective value corresponding to the first sampling segment, represents the measured voltage peak value corresponding to the first sampling segment; and the first relationship curve is obtained based on the resistance values and the resistance current peak values of the plurality of sampling segments.

[0012] Optionally, in the case that the measured current effective value data comprises measured current effective values corresponding to the plurality of sampling segments, and the magnetic flux data comprises magnetic flux values corresponding to the plurality of sampling segments, the nonlinear inductance data of the voltage transformer in the preset sampling period is determined based on the resistance current peak value data, the measured current effective value data, and the magnetic flux data by a second point-by-point recursion method, which comprises: obtaining resistance current effective values corresponding to the plurality of sampling segments based on the resistance current peak values corresponding to the plurality of sampling segments; determining inductance current effective values corresponding to the plurality of sampling segments according to the resistance current effective values and the measured current effective values corresponding to the plurality of sampling segments; and determining the nonlinear inductance data corresponding to the plurality of sampling segments based on the inductance current effective values and the magnetic flux values corresponding to the plurality of sampling segments by the second point-by-point recursion method.

[0013] Optionally, the inductance current effective values corresponding to the plurality of sampling segments are determined based on the resistance current effective values and the measured current effective values corresponding to the plurality of sampling segments by the following method:

[0014]

[0015] wherein, Ik represents the inductance current effective value corresponding to the kth sampling segment in the plurality of sampling segments, Ik-1 represents the inductance current effective value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, and Ik+1 represents the inductance current effective value corresponding to the (k+1)th sampling segment in the plurality of sampling segments. L_RMSk RMSk R_RMSk wherein, Ik represents the inductance current effective value corresponding to the kth sampling segment in the plurality of sampling segments, Ik-1 represents the inductance current effective value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, and Ik+1 represents the inductance current effective value corresponding to the (k+1)th sampling segment in the plurality of sampling segments.

[0016] Optionally, the second point-by-point recursive method is used to determine the nonlinear inductance data corresponding to the plurality of sampling segments based on the inductance current effective values and the magnetic flux values corresponding to the plurality of sampling segments, and the nonlinear inductance data includes the inductance values corresponding to the plurality of sampling segments.

[0017]

[0018] wherein, φk represents the magnetic flux value corresponding to the kth sampling segment in the plurality of sampling segments, φk-1 represents the magnetic flux value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, and φk+1 represents the magnetic flux value corresponding to the (k+1)th sampling segment in the plurality of sampling segments. km (k-1)m L_RMS(k-1) k wherein, Ik represents the inductance current effective value corresponding to the kth sampling segment in the plurality of sampling segments, Ik-1 represents the inductance current effective value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, and Ik+1 represents the inductance current effective value corresponding to the (k+1)th sampling segment in the plurality of sampling segments.

[0019] Optionally, the second relationship curve between the nonlinear inductance data and the inductance current peak value data of the voltage transformer in the preset sampling period is determined based on the nonlinear inductance data, and the inductance current peak value data includes the inductance current peak values corresponding to the plurality of sampling segments.

[0020]

[0021] wherein, ik represents the inductance current peak value corresponding to the kth sampling segment in the plurality of sampling segments, and the second relationship curve is obtained based on the inductance values and the inductance current peak values corresponding to the plurality of sampling segments. Lk

[0022] ​​​​​​​Optionally, the model simulation processing according to the first relationship curve and the second relationship curve to obtain the voltage transformer model comprises: performing model simulation processing based on the first relationship curve to obtain a nonlinear resistance model; and performing model simulation based on the second relationship curve to obtain a nonlinear inductance model; and performing parallel processing on the nonlinear resistance model and the nonlinear inductance model to obtain the voltage transformer model.

[0023] According to another aspect of the embodiment of the present application, a determination device of a voltage transformer model is further provided, comprising: a first obtaining module, configured to obtain measured voltage effective value data, measured current effective value data, magnetic flux data and no-load loss curve of a voltage transformer in a preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operation state; a first determining module, configured to determine nonlinear resistance data of the voltage transformer in the preset sampling period by using a first point-by-point recursive method based on the measured voltage effective value data and the active power data; a second determining module, configured to determine resistance current peak value data of the voltage transformer in the preset sampling period and a first relationship curve between the nonlinear resistance data and the resistance current peak value data based on the nonlinear resistance data; a third determining module, configured to determine nonlinear inductance data of the voltage transformer in the preset sampling period by using a second point-by-point recursive method based on the resistance current peak value data, the measured current effective value data and the magnetic flux data; a fourth determining module, configured to determine inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the nonlinear inductance data and the inductance current peak value data based on the nonlinear inductance data; and a second obtaining module, configured to perform model simulation processing according to the first relationship curve and the second relationship curve to obtain the voltage transformer model.

[0024] According to another aspect of the embodiment of the present application, a non-volatile storage medium is further provided, which stores a plurality of instructions, and the instructions are suitable for being loaded and executed by a processor to perform any one of the determination methods of the voltage transformer model.

[0025] In the embodiment of the present application, the measured voltage effective value data, the measured current effective value data, the magnetic flux data and the no-load loss curve of the voltage transformer in a preset sampling period are obtained, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and the corresponding active power data when the voltage transformer is in a no-load operation state; based on the measured voltage effective value data and the active power data, the first point-by-point recursive method is used to determine the non-linear resistance data of the voltage transformer in the preset sampling period; based on the non-linear resistance data, the resistance current peak value data of the voltage transformer in the preset sampling period and the first relationship curve between the non-linear resistance data and the resistance current peak value data are determined; based on the resistance current peak value data, the measured current effective value data and the magnetic flux data, the second point-by-point recursive method is used to determine the non-linear inductance data of the voltage transformer in the preset sampling period; based on the non-linear inductance data, the inductance current peak value data of the voltage transformer in the preset sampling period and the second relationship curve between the non-linear inductance data and the inductance current peak value data are determined; the model simulation processing is performed according to the first relationship curve and the second relationship curve, and the voltage transformer model is obtained, so as to achieve the technical effect of constructing a voltage transformer equivalent model composed of non-linear inductance and non-linear resistance, accurately reflecting the characteristics of the actual voltage transformer, improving the accuracy and practicability of the voltage transformer model, and further improving the model simulation effect, thereby solving the technical problems of low model construction accuracy and poor simulation effect caused by the voltage transformer model in the related art. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings, which are included to provide a further understanding of the present application and are incorporated in and constitute a part of this application, illustrate embodiments of the present application and together with the description serve to explain the present application. In the drawings:

[0027] Figure 1 It is a flow chart of a determination method of a voltage transformer model according to the embodiment of the present application;

[0028] Figure 2 It is a schematic diagram of the relationship between the measured voltage effective value and the active power according to an optional embodiment of the present application;

[0029] Figure 3 It is a schematic diagram of calculating the non-linear resistance voltage current by the point-by-point recursive method according to an optional embodiment of the present application;

[0030] Figure 4 It is a schematic diagram of calculating the non-linear inductance magnetic flux current by the point-by-point recursive method according to an optional embodiment of the present application;

[0031] Figure 5 is a single-phase electromagnetic voltage transformer model of optional parallel connection of a non-linear resistance and a non-linear inductance according to an embodiment of the present application;

[0032] Figure 6a is a schematic diagram of three-phase voltage waveforms at a high-voltage side of a voltage transformer after disappearance of a single-phase ground fault according to the prior art;

[0033] Figure 6b is a schematic diagram of three-phase voltage waveforms at a high-voltage side of a voltage transformer after disappearance of a single-phase ground fault according to an embodiment of the present application;

[0034] Figure 7 is a structural schematic diagram of a determination device of a voltage transformer model according to an embodiment of the present application. DETAILED DESCRIPTION

[0035] In order to make the personnel in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by the person of ordinary skill in the art without creative labor should belong to the scope of protection of the present application.

[0036] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0037] In power distribution system, the neutral point of the system adopts ungrounded operation mode to improve the power supply reliability of the power system. For this purpose, an electromagnetic potential transformer (PT) is installed on the bus of the power plant and the transformer substation. The high voltage winding of the installed PT is star connected and the neutral point is effectively grounded, which is used to monitor the bus voltage to ground and the relay protection action of the transformer substation. In normal operation, the potential transformer has a high reactance, and the voltages of the three phases are basically consistent. The unbalanced voltage of the potential transformer is only derived from the unbalance of the three-phase capacitance to ground. When the system fails or is abnormally disturbed, the excitation inductance of the PT is prone to core saturation due to its nonlinear characteristics, which causes the excitation inductance to decrease, and under certain conditions, the system capacitance parameters are matched to cause ferroresonance overvoltage. This kind of overvoltage is one of the internal overvoltages of the distribution network, which is prone to occur during power grid operation or fault process, causing the power grid to operate in an abnormal state for a long time, which may cause the PT fuse to blow or even explode, and eventually may cause three-phase fault of the system, which poses a great threat to the safe operation of the power system.

[0038] In the study of ferroresonance overvoltage of power distribution system and fuse blowing process of potential transformer, the most commonly used method is to analyze the fault causes and study the corresponding resonance elimination measures by simulation modeling. The system model established by combining the actual situation of device parameters and wiring is the basis of the research, and the most critical is the establishment of the potential transformer model. The accuracy of the potential transformer model directly affects the accuracy of the simulation results. Since the potential transformer is approximately in no-load state in normal operation, the current simulation usually equivalent single-phase potential transformer to a nonlinear inductor and a resistor in series, and uses the peak flux-current curve to represent its nonlinearity. However, in fact, the core has hysteresis loss and eddy current loss, which shows active property. The commonly used model cannot well reflect the actual characteristics of the potential transformer, and the accuracy of the potential transformer model is poor, which leads to deviation of the model simulation test from the actual situation.

[0039] According to the embodiment of the present application, a method for determining the potential transformer model is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0040] Figure 1 The flowchart of the method for determining the potential transformer model according to the embodiment of the present application is shown in FIG. 1, which includes the following steps: Figure 1

[0041] ​In step S102, the measured voltage effective value data, the measured current effective value data, the magnetic flux data and the no-load loss curve of the voltage transformer in the preset sampling period are obtained, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and the corresponding active power data when the voltage transformer is in the no-load operation state.

[0042] Optionally, the voltage transformer can be but is not limited to a single-phase electromagnetic voltage transformer, and the corresponding voltage transformer model can be but is not limited to a single-phase electromagnetic voltage transformer model. The measured voltage effective value data and the measured current effective value data can be obtained by obtaining the voltage waveform data and the current waveform data obtained from the actual field 10kV voltage transformer volt-ampere characteristic test.

[0043] Optionally, as shown in Figure 2 The no-load loss curve is obtained when the voltage transformer is in the no-load operation state by applying different voltages to the voltage transformer, and is used to indicate the relationship between the measured voltage effective value data and the corresponding active power data when the voltage transformer is in the no-load operation state. Therefore, after the no-load loss curve is obtained, the corresponding active power data can be obtained for subsequent calculation.

[0044] In an optional embodiment, when the measured voltage effective value data includes the measured voltage effective value corresponding to each of the plurality of sampling segments of the voltage transformer in the preset sampling period, and the active power data includes the active power corresponding to each of the plurality of sampling segments, the non-linear resistance data of the voltage transformer in the preset sampling period is determined based on the measured voltage effective value data and the active power data by using a first point-by-point recursive method, including:

[0045] The non-linear resistance data is determined based on the measured voltage effective value and the active power corresponding to each of the plurality of sampling segments by using the first point-by-point recursive method, wherein the non-linear resistance data includes the resistance value corresponding to each of the plurality of sampling segments.

[0046]

[0047] wherein P k represents the active power corresponding to the kth sampling segment of the plurality of sampling segments, represents the voltage peak value corresponding to the kth sampling segment, U RMSk represents the measured voltage effective value corresponding to the kth sampling segment, θ k represents the phase angle corresponding to the kth sampling segment, R k represents the resistance value corresponding to the kth sampling segment.

[0048] It can be understood that the above-mentioned multiple sampling sections are multiple linear sampling sections. Since the equivalent nonlinear resistance of the voltage transformer is a nonlinear resistance, the corresponding nonlinear resistance data can be obtained by the voltage-current (i.e., ui R It can be understood that if ui is known R Curve, assuming that ui is known R curve, and the effective value of the voltage applied to the voltage transformer is U RMS2 , the voltage peak is U 2m , Then the instantaneous value of the voltage across the equivalent nonlinear resistor is (θ represents the phase angle), considering the symmetry, the preset sampling period is set to 1 / 4 period. Figure 3 The nonlinear resistance ui R The instantaneous value of the current across the equivalent nonlinear resistor can be obtained by piecewise linearization of the curve:

[0049]

[0050]

[0051] The above process can be done by ui R The curves show the i under different applied voltages. R (θ) and u(θ), from which we can get i R (θ) is expressed in 1 / 4 period, so the active power under the corresponding voltage can be calculated by the power calculation formula:

[0052]

[0053] Considering the inverse problem, the no-load loss curve of the voltage transformer under different voltages measured in the experiment is used to obtain ui R The curve needs to be determined first.

[0054] Let U RMSk is the effective value of the applied voltage, U km is the applied voltage peak, P k The effective value is U RMSk The no-load loss of the voltage transformer is k=1, 2, 3, ..., m. Figure 3 As shown, ui R The first linear segment of the curve In ui R In the kth (k≥2) linear segment of the curve, according to the definition of power:

[0055] u(θ)=Ukm sinθ

[0056]

[0057] θ j =arcsin(U jm / U km )j=1,2,…,k-1

[0058] The only unknown quantity in the formula is the resistance value R corresponding to the kth sampling segment among multiple sampling segments. k , we can calculate R k value.

[0059] Step S106 , determining the resistance current peak data of the voltage transformer within the preset sampling period and a first relationship curve between the nonlinear resistance data and the resistance current peak data based on the nonlinear resistance data.

[0060] In an optional embodiment, the determining, based on the nonlinear resistance data, the resistance current peak data of the voltage transformer within the preset sampling period, and a first relationship curve between the nonlinear resistance data and the resistance current peak data includes:

[0061] Based on the resistance values ​​corresponding to the plurality of sampling segments, the resistance current peak data is determined in the following manner, wherein the resistance current peak data includes the resistance current peak values ​​corresponding to the plurality of sampling segments:

[0062]

[0063] Among them, i Rk represents the peak value of the resistor current corresponding to the kth sampling segment, and the i R(k-1) Indicates the resistance current peak value corresponding to the (k-1)th sampling segment in the above multiple sampling segments, U k(m-1) represents the voltage peak value corresponding to the (k-1)th sampling segment, P1 represents the active power corresponding to the first sampling segment among the multiple sampling segments, U RMS1 Indicates the effective value of the measured voltage corresponding to the first sampling segment above, Indicates the measured voltage peak value corresponding to the first sampling segment above;

[0064] The first relationship curve is obtained based on the resistance values ​​and the resistance current peak values ​​respectively corresponding to the plurality of sampling segments.

[0065] Optionally, the first relationship curve may be, but is not limited to, a volt-ampere characteristic curve corresponding to the equivalent nonlinear resistance of the voltage transformer (ie, ui R curve).

[0066] Optionally, the resistance value Rk corresponding to the kth sampling segment in the plurality of sampling segments is further determined based on the measured current effective value and the magnetic flux value. k The resistance current peak value ik corresponding to the kth sampling segment in the plurality of sampling segments can be calculated as follows: Rk

[0067]

[0068] Thus, the resistance current peak value ik corresponding to each sampling segment can be calculated. The voltage-current characteristic curve (i.e., u-i curve) of the equivalent non-linear resistance of the voltage transformer simulating the magnetic hysteresis eddy current loss is obtained by programming iterative calculation in the simulation software MATLAB based on the measured data. Rk R

[0069] In step S108, the non-linear inductance data of the voltage transformer in the preset sampling period is determined based on the resistance current peak value data, the measured current effective value data, and the magnetic flux data by using a second point-by-point recursive method.

[0070] Optionally, the non-linear inductance data corresponding to the plurality of sampling segments in the preset sampling period is obtained by converting based on the resistance current peak value data, the measured current effective value data, and the magnetic flux data by using the second point-by-point recursive method.

[0071] In an optional embodiment, when the measured current effective value data includes the measured current effective values corresponding to the plurality of sampling segments, and the magnetic flux data includes the magnetic flux values corresponding to the plurality of sampling segments, the non-linear inductance data of the voltage transformer in the preset sampling period is determined based on the resistance current peak value data, the measured current effective value data, and the magnetic flux data by using the second point-by-point recursive method, including:

[0072] The resistance current effective values corresponding to the plurality of sampling segments are obtained based on the resistance current peak values corresponding to the plurality of sampling segments.

[0073] The inductance current effective values corresponding to the plurality of sampling segments are determined based on the resistance current effective values corresponding to the plurality of sampling segments and the measured current effective values.

[0074] The non-linear inductance data corresponding to the plurality of sampling segments is determined based on the inductance current effective values corresponding to the plurality of sampling segments and the magnetic flux values by using the second point-by-point recursive method.

[0075] ​​​In an alternative embodiment, the determination of the inductive current effective value corresponding to each of the plurality of sampling segments based on the resistance current effective value and the measured current effective value corresponding to each of the plurality of sampling segments comprises:

[0076] The inductive current effective value corresponding to each of the plurality of sampling segments is obtained based on the resistance current effective value and the measured current effective value corresponding to each of the plurality of sampling segments by:

[0077]

[0078] wherein I L_RMSk represents the inductive current effective value corresponding to the kth sampling segment of the plurality of sampling segments, I RMSk represents the measured current effective value corresponding to the kth sampling segment, and I R_RMSk represents the resistance current effective value corresponding to the kth sampling segment.

[0079] Optionally, the measured measured voltage effective value is U RMSk , the measured voltage peak value is U km , the measured measured current effective value is I RMSk , and k = 1, 2, 3,..., m.

[0080] Since the applied voltage is sinusoidal, the transformation of voltage and magnetic flux satisfies the following relationship: φ km = U km / ω, wherein φ km represents the magnetic flux value corresponding to the kth sampling segment of the plurality of sampling segments, and ω represents the angular velocity. Based on the resistance current peak value i Rk corresponding to each of the plurality of sampling segments obtained in the modeling of the non-linear resistor, the resistance current effective value I R_RMSk corresponding to each of the plurality of sampling segments can be calculated. Further, the non-linear inductive current effective value corresponding to each of the plurality of sampling segments can be calculated.

[0081] In an alternative embodiment, the determination of the non-linear inductive data corresponding to each of the plurality of sampling segments based on the inductive current effective value and the magnetic flux value corresponding to each of the plurality of sampling segments by using the second point-by-point recursive method comprises:

[0082] The non-linear inductive data corresponding to each of the plurality of sampling segments is obtained based on the inductive current effective value and the magnetic flux value corresponding to each of the plurality of sampling segments by using the second point-by-point recursive method, wherein the non-linear inductive data comprises the inductive value corresponding to each of the plurality of sampling segments.

[0083]

[0084] wherein, φ km represents the magnetic flux value corresponding to the kth sampling segment in the plurality of sampling segments, φ (k-1)m represents the magnetic flux value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, represents the inductance current peak value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, I L_RMS(k-1) represents the inductance current effective value corresponding to the (k-1)th sampling segment in the plurality of sampling segments, L k represents the inductance value corresponding to the kth sampling segment in the plurality of sampling segments.

[0085] Optionally, set i L is the inductance current peak value corresponding to each sampling segment, k = 1, 2, 3, …, m, the inductance current peak value corresponding to the first sampling segment in the Φ-i curve is I the kth (k≥2) linear segment in the Φ-i curve, by I L_RMSk the peak value of the current i Lk can be obtained; assuming φ(θ) = φ km sinθ, then

[0086]

[0087] In the formula, only Lk is unknown, so the above formula can be summarized as: The above formula is a monomial quadratic equation, wherein a Lk , b Lk , c Lk are known, and the inductance values L k corresponding to the plurality of sampling segments are easily obtained.

[0088] Step S110, based on the nonlinear inductance data, determine the inductance current peak value data of the voltage transformer in the preset sampling period, and a second relationship curve between the nonlinear inductance data and the inductance current peak value data.

[0089] Optionally, the second relationship curve can be but is not limited to the magnetic flux-current curve (i.e. Φ-i curve) corresponding to the voltage transformer, Figure 4 is an optional point-by-point recursive method for calculating nonlinear inductance magnetic flux current according to an embodiment of the application, as Figure 4 shown, the magnetic flux-current curve (i.e. Φ-i curve) corresponding to the equivalent nonlinear inductance of the voltage transformer is linearized by segments, according to the nonlinear inductance data corresponding to the plurality of sampling segments in the preset sampling period, the inductance current peak value data corresponding to the plurality of sampling segments in the preset sampling period is derived, and then the linearized magnetic flux-current curve is obtained.

[0090] In an alternative embodiment, the determining, based on the nonlinear inductance data, of the inductance current peak value data of the voltage transformer in the preset sampling period and the second relationship curve between the nonlinear inductance data and the inductance current peak value data comprises:

[0091] The inductance current peak value data comprises inductance current peak values corresponding to the plurality of sampling segments, and the inductance current peak values are obtained based on the inductance values corresponding to the plurality of sampling segments in the following manner:

[0092]

[0093] wherein I L_RMS1 represents the effective value of the inductance current corresponding to the first sampling segment in the plurality of sampling segments, i Lk represents the inductance current peak value corresponding to the kth sampling segment in the plurality of sampling segments.

[0094] The second relationship curve is obtained based on the inductance values corresponding to the plurality of sampling segments and the inductance current peak values.

[0095] Optionally, the inductance current peak value corresponding to the first sampling segment is determined directly, and the inductance current peak values corresponding to the plurality of sampling segments (k>=2) are obtained based on the inductance values corresponding to the plurality of sampling segments in the following manner: All current peak values i Lk The actual Φ-i curve can be deduced reversely.

[0096] In step S112, model simulation processing is performed according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

[0097] In an alternative embodiment, the model simulation processing performed according to the first relationship curve and the second relationship curve to obtain a voltage transformer model comprises:

[0098] The model simulation processing comprises model simulation processing based on the first relationship curve to obtain a nonlinear resistance model and model simulation processing based on the second relationship curve to obtain a nonlinear inductance model.

[0099] The voltage transformer model is obtained by parallel processing of the nonlinear resistance model and the nonlinear inductance model.

[0100] Optionally, Figure 5 is a single-phase electromagnetic voltage transformer model of an alternative nonlinear resistance and nonlinear inductance according to an embodiment of the present application, as shown in Figure 5 ​As shown, the above voltage transformer model is obtained by connecting a nonlinear resistance model R in parallel with a nonlinear inductance model L.

[0101] It should be noted that for a single-phase electromagnetic voltage transformer, the core actually has hysteresis loss and eddy current loss, which exhibits active properties, resulting in that the measured voltage and current values are not 90° out of phase, so the core should be equivalent to a parallel model of a nonlinear resistance and a nonlinear inductance. Thus, the voltage transformer model obtained by parallel processing the obtained nonlinear resistance model and nonlinear inductance model can better reflect the actual operating characteristics of the single-phase electromagnetic voltage transformer.

[0102] Through the above steps S102 to S112, the equivalent model of the voltage transformer composed of the nonlinear inductance and the nonlinear resistance is constructed, the actual voltage transformer characteristics are accurately reflected, the accuracy and practicability of the voltage transformer model are improved, the simulation effect of the model is improved, and the technical problems of low model construction accuracy and poor simulation effect caused by the voltage transformer model in the related art are solved.

[0103] Optionally, after obtaining the above voltage transformer model, an electromagnetic transient simulation system model is established based on the voltage transformer model. For example, according to a 220kV / 10kV substation 10kV side system, an improved model of a neutral point ungrounded system is established, which specifically includes a main transformer model, a line model, a load model, and a voltage transformer model. For the main transformer model, a matrix representation method BCTRAN model in an electromagnetic transient calculation program ATP-EMTP is used to simulate the main transformer, and the parameters are derived from the factory test report, and the input parameters include core type, high, medium and low winding voltage level, and no-load experiment and short-circuit experiment data in the factory test. For the line model, the line in the neutral point ungrounded system includes a cable line and an overhead line, and the actual line parameters can be determined by using the related model in the electromagnetic transient calculation program ATP-EMTP. For the load model, the distribution network load is represented by a neutral point ungrounded resistance-inductance-capacitance (i.e. R-L-C) inductive element instead. For the voltage transformer model: a single-phase voltage transformer is equivalent to a parallel connection of a nonlinear inductance (type 93 inductance in ATP-EMTP) and a nonlinear resistance.

[0104] A single-phase grounding disappearance fault condition is set, under the same system parameter condition, the three-phase voltage at the high voltage side of the electromagnetic voltage transformer model when only the nonlinear inductance model is used is shown in FIG. 6(a), and the three-phase voltage at the high voltage side of the electromagnetic voltage transformer model when the parallel connection of the nonlinear inductance and the nonlinear resistance model is used is shown in FIG. 6(b), it can be seen that different models have a great influence on the development of actual ferroresonance.

[0105] There is also provided in the embodiments a voltage transformer model determination apparatus for implementing the above-described embodiments and preferred embodiments, which have been described above. As used below, the term "module" "apparatus" can be a combination of software and / or hardware that implements a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.

[0106] According to the embodiments of the present application, there is also provided an apparatus embodiment for implementing the above-described voltage transformer model determination method, Figure 7 is a structural schematic diagram of a voltage transformer model determination apparatus according to the embodiments of the present application, as Figure 7 shown, the above-described voltage transformer model determination apparatus comprises a first acquisition module 700, a first determination module 702, a second determination module 704, a third determination module 706, a fourth determination module 708, and a second acquisition module 710, wherein:

[0107] The first acquisition module 700 is configured to acquire measurement voltage effective value data, measurement current effective value data, magnetic flux data, and no-load loss curve data of a voltage transformer within a preset sampling period, wherein the no-load loss curve data is used to indicate the relationship between the measurement voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operation state.

[0108] The first determination module 702 is connected to the first acquisition module 700 and is configured to determine non-linear resistance data of the voltage transformer within the preset sampling period based on the measurement voltage effective value data and the active power data by using a first point-by-point recursive method.

[0109] The second determination module 704 is configured to determine resistance current peak value data of the voltage transformer within the preset sampling period and a first relationship curve between the non-linear resistance data and the resistance current peak value data based on the non-linear resistance data.

[0110] The third determination module 706 is connected to the second determination module 704 and is configured to determine non-linear inductance data of the voltage transformer within the preset sampling period based on the resistance current peak value data, the measurement current effective value data, and the magnetic flux data by using a second point-by-point recursive method.

[0111] The fourth determination module 708 is connected to the third determination module 706 and is configured to determine, based on the nonlinear inductance data, the inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the nonlinear inductance data and the inductance current peak value data.

[0112] The second acquisition module 710 is connected to the fourth determination module 708 and is configured to perform model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

[0113] In the embodiment of the present application, the first acquisition module 700 is configured to acquire the measured voltage effective value data, the measured current effective value data, the magnetic flux data and the no-load loss curve of the voltage transformer in the preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and the corresponding active power data when the voltage transformer is in a no-load operation state. The first determination module 702 is connected to the first acquisition module 700 and is configured to determine, based on the measured voltage effective value data and the active power data, the nonlinear resistance data of the voltage transformer in the preset sampling period by using a first point-by-point recursion method. The second determination module 704 is configured to determine, based on the nonlinear resistance data, the resistance current peak value data of the voltage transformer in the preset sampling period and a first relationship curve between the nonlinear resistance data and the resistance current peak value data. The third determination module 706 is connected to the second determination module 704 and is configured to determine, based on the resistance current peak value data, the measured current effective value data and the magnetic flux data, the nonlinear inductance data of the voltage transformer in the preset sampling period by using a second point-by-point recursion method. The fourth determination module 708 is connected to the third determination module 706 and is configured to determine, based on the nonlinear inductance data, the inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the nonlinear inductance data and the inductance current peak value data. The second acquisition module 710 is connected to the fourth determination module 708 and is configured to perform model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model. The technical effect of the present application is to construct a voltage transformer equivalent model composed of nonlinear inductance and nonlinear resistance, accurately reflect the characteristics of the actual voltage transformer, improve the accuracy and practicability of the voltage transformer model, and thus improve the model simulation effect. In this way, the technical problem of low model construction accuracy and poor simulation effect caused by the voltage transformer model in the related art is solved.

[0114] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0115] It should be noted that the first acquisition module 700, first determination module 702, second determination module 704, third determination module 706, fourth determination module 708, and second acquisition module 710 described above correspond to steps S102 to S112 in the embodiment. The examples and application scenarios implemented by these modules and corresponding steps are the same, but are not limited to the contents disclosed in the above embodiment. It should be noted that the above modules, as part of the device, can be run on a computer terminal.

[0116] It should be noted that the optional or preferred implementation of this embodiment can be found in the relevant description in the embodiment, which will not be repeated here.

[0117] The above-mentioned voltage transformer model determination device may also include a processor and a memory. The above-mentioned first acquisition module 700, first determination module 702, second determination module 704, third determination module 706, fourth determination module 708, second acquisition module 710, etc. are all stored in the memory as program modules, and the processor executes the above-mentioned program modules stored in the memory to realize the corresponding functions.

[0118] The processor includes a core, which retrieves corresponding program modules from memory. There can be one or more cores. Memory may include non-permanent memory in a computer-readable medium, random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory includes at least one memory chip.

[0119] According to an embodiment of the present application, an embodiment of a non-volatile storage medium is further provided. Optionally, in this embodiment, the non-volatile storage medium includes a stored program, wherein when the program is executed, the device containing the non-volatile storage medium is controlled to execute any of the above-mentioned methods for determining a voltage transformer model.

[0120] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a computer terminal group in a computer network, or in any mobile terminal in a mobile terminal group, and the non-volatile storage medium includes a stored program.

[0121] Optionally, during program running, the device in which the nonvolatile storage medium is located is controlled to perform the following functions: obtaining measured voltage effective value data of the voltage transformer in a preset sampling period, measured current effective value data, magnetic flux data, and no-load loss curve, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operating state; based on the measured voltage effective value data and the active power data, using a first point-by-point recursive method to determine non-linear resistance data of the voltage transformer in the preset sampling period; based on the non-linear resistance data, determining resistance current peak value data of the voltage transformer in the preset sampling period and a first relationship curve between the non-linear resistance data and the resistance current peak value data; based on the resistance current peak value data, the measured current effective value data, and the magnetic flux data, using a second point-by-point recursive method to determine non-linear inductance data of the voltage transformer in the preset sampling period; based on the non-linear inductance data, determining inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the non-linear inductance data and the inductance current peak value data; and performing model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

[0122] According to the embodiments of the present application, an embodiment of a processor is also provided. Optionally, in the embodiment, the processor is used to run a program, wherein the program performs any one of the determination methods of the voltage transformer model during program running.

[0123] According to the embodiments of the present application, an embodiment of a computer program product is also provided, which is adapted to execute the program steps of the determination method of any one of the voltage transformer models when executed on a data processing device.

[0124] Optionally, the computer program product described above, when executed on a data processing device, is adapted to execute a program that initializes the following method steps: obtaining measured voltage effective value data, measured current effective value data, magnetic flux data and no-load loss curve of a voltage transformer in a preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operating state; based on the measured voltage effective value data and the active power data, using a first point-by-point recursive method to determine the non-linear resistance data of the voltage transformer in the preset sampling period; based on the non-linear resistance data, determining the resistance current peak value data of the voltage transformer in the preset sampling period and a first relationship curve between the non-linear resistance data and the resistance current peak value data; based on the resistance current peak value data, the measured current effective value data and the magnetic flux data, using a second point-by-point recursive method to determine the non-linear inductance data of the voltage transformer in the preset sampling period; based on the non-linear inductance data, determining the inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the non-linear inductance data and the inductance current peak value data; performing model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

[0125] The embodiment of the present application provides an electronic device, which comprises a processor, a memory and a program stored on the memory and executable on the processor, and the processor implements the following steps when executing the program: obtaining measured voltage effective value data, measured current effective value data, magnetic flux data and no-load loss curve of a voltage transformer in a preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measured voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operating state; based on the measured voltage effective value data and the active power data, using a first point-by-point recursive method to determine the non-linear resistance data of the voltage transformer in the preset sampling period; based on the non-linear resistance data, determining the resistance current peak value data of the voltage transformer in the preset sampling period and a first relationship curve between the non-linear resistance data and the resistance current peak value data; based on the resistance current peak value data, the measured current effective value data and the magnetic flux data, using a second point-by-point recursive method to determine the non-linear inductance data of the voltage transformer in the preset sampling period; based on the non-linear inductance data, determining the inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the non-linear inductance data and the inductance current peak value data; performing model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

[0126] The above-mentioned embodiment numbers of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0127] In the above-mentioned embodiments of the present application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0128] In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other ways. Among them, the above-mentioned device embodiments are only schematic, for example, the division of the above-mentioned modules can be a logical function division, and in actual implementation, there can be another division way, for example, a plurality of modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed each other can be through some interface, indirect coupling or communication connection of modules or modules, which can be electrical or other forms.

[0129] The above-mentioned modules described as separate components can be or can not be physically separated, and the components displayed as modules can be or can not be physical modules, that is, they can be located in one place, or can be distributed to a plurality of modules. According to the actual needs, some or all of the modules can be selected to achieve the purpose of the present embodiment scheme.

[0130] In addition, each functional module in each embodiment of the present application can be integrated in a processing module, or each module can exist physically, or two or more modules can be integrated in one module. The above-mentioned integrated module can be realized in the form of hardware or in the form of software functional module.

[0131] The above-mentioned integrated module, if realized in the form of software functional module and sold or used as an independent product, can be stored in a computer readable non-volatile storage medium. Based on this understanding, the technical scheme of the present application or the part of the prior art or the whole or part of the technical scheme can be embodied in the form of software product, which is stored in a non-volatile storage medium, including a plurality of instructions for making a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the embodiments of the present application. The above-mentioned non-volatile storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and various program code storage media.

[0132] The above merely is the preferred embodiment of the present application, it should be pointed out that, for ordinary skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method of determining a model of a voltage transformer, characterized by, The method comprises: obtaining measurement voltage effective value data, measurement current effective value data, magnetic flux data and no-load loss curve of the voltage transformer in a preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measurement voltage effective value data and corresponding active power data when the voltage transformer is in a no-load operation state; based on the measurement voltage effective value data and the active power data, using a first point-by-point recursive method to determine the non-linear resistance data of the voltage transformer in the preset sampling period; based on the non-linear resistance data, determining the resistance current peak value data of the voltage transformer in the preset sampling period and a first relationship curve between the non-linear resistance data and the resistance current peak value data; based on the resistance current peak value data, the measurement current effective value data and the magnetic flux data, using a second point-by-point recursive method to determine the non-linear inductance data of the voltage transformer in the preset sampling period; based on the non-linear inductance data, determining the inductance current peak value data of the voltage transformer in the preset sampling period and a second relationship curve between the non-linear inductance data and the inductance current peak value data; performing model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

2. The method of claim 1, wherein, In the case that the measurement voltage effective value data comprises measurement voltage effective values corresponding to a plurality of sampling segments of the voltage transformer in the preset sampling period, and the active power data comprises active powers corresponding to the plurality of sampling segments, the method comprises: based on the measurement voltage effective values and the active powers corresponding to the plurality of sampling segments, using the first point-by-point recursive method to determine the non-linear resistance data, wherein the non-linear resistance data comprises resistance values corresponding to the plurality of sampling segments. wherein P k represents the active power corresponding to the kth sampling segment of the plurality of sampling segments, represents the voltage peak value corresponding to the kth sampling segment, U RMSk represents the measured voltage effective value corresponding to the kth sampling segment, θ k represents the phase angle corresponding to the kth sampling segment, R k represents the resistance value corresponding to the kth sampling segment.

3. The method of claim 2, wherein, In the case that the measurement current effective value data comprises measurement current effective values corresponding to the plurality of sampling segments, and the magnetic flux data comprises magnetic flux values corresponding to the plurality of sampling segments, the method comprises: based on the resistance values and the inductance current peak values corresponding to the plurality of sampling segments, obtaining the first relationship curve. wherein, i Rk denotes the resistance current peak value corresponding to the kth sampling section, and i R(k-1) denotes the resistance current peak value corresponding to the (k-1)th sampling section in the plurality of sampling sections, U k(m-1) denotes the voltage peak value corresponding to the (k-1)th sampling section, P1 denotes the active power corresponding to the 1st sampling section in the plurality of sampling sections, U RMS1 denotes the measured voltage effective value corresponding to the 1st sampling section, denotes the measured voltage peak value corresponding to the 1st sampling section; ​ 4. The method of claim 3, wherein, ​ obtaining, based on the resistance current peak values corresponding to the plurality of sampling segments respectively, resistance current effective values corresponding to the plurality of sampling segments respectively; determining, according to the resistance current effective values corresponding to the plurality of sampling segments respectively and the measurement current effective value, inductance current effective values corresponding to the plurality of sampling segments respectively; based on the inductance current effective values corresponding to the plurality of sampling segments respectively and the magnetic flux value, using the second point-by-point recursive method to determine the nonlinear inductance data corresponding to the plurality of sampling segments respectively.

5. The method of claim 4, wherein, The determination of the inductance current effective values corresponding to the plurality of sampling segments respectively according to the resistance current effective values corresponding to the plurality of sampling segments respectively and the measurement current effective value includes: Based on the resistance current effective values corresponding to the plurality of sampling segments respectively and the measurement current effective value, the inductance current effective values corresponding to the plurality of sampling segments respectively are obtained by the following method: wherein I L_RMSk represents the inductive current effective value corresponding to the kth sampling segment in the plurality of sampling segments, I RMSk represents the measurement current effective value corresponding to the kth sampling segment, I R_RMSk represents the resistive current effective value corresponding to the kth sampling segment.

6. The method of claim 5, wherein, The determination of the nonlinear inductance data corresponding to the plurality of sampling segments respectively based on the inductance current effective values corresponding to the plurality of sampling segments respectively and the magnetic flux value using the second point-by-point recursive method includes: Based on the inductance current effective values corresponding to the plurality of sampling segments respectively and the magnetic flux value, the nonlinear inductance data corresponding to the plurality of sampling segments respectively is obtained by using the second point-by-point recursive method, wherein the nonlinear inductance data includes inductance values corresponding to the plurality of sampling segments respectively. wherein φ km denotes the magnetic flux value corresponding to the kth sampling segment of the plurality of sampling segments, φ (k-1)m denotes the magnetic flux value corresponding to the (k-1)th sampling segment of the plurality of sampling segments, denotes the inductance current peak value corresponding to the (k-1)th sampling segment of the plurality of sampling segments, I L_RMS(k-1) denotes the inductance current effective value corresponding to the (k-1)th sampling segment of the plurality of sampling segments, L k denotes the inductance value corresponding to the kth sampling segment of the plurality of sampling segments.

7. The method of claim 6, wherein, The determination of the inductance current peak value data of the voltage transformer within the preset sampling period based on the nonlinear inductance data and the second relationship curve between the nonlinear inductance data and the inductance current peak value data includes: Based on the inductance values corresponding to the plurality of sampling segments respectively, the inductance current peak value data is obtained by the following method, wherein the inductance current peak value data includes the inductance current peak values corresponding to the plurality of sampling segments respectively. wherein i Lk indicates the inductance current peak value corresponding to the kth sampling segment in the plurality of sampling segments. Based on the inductance values corresponding to the plurality of sampling segments respectively and the inductance current peak values, the second relationship curve is obtained.

8. The method according to any one of claims 1 to 7, characterized in that, The model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model includes: Based on the first relationship curve, a nonlinear resistance model is obtained by model simulation processing, and based on the second relationship curve, a nonlinear inductance model is obtained by model simulation; Parallel processing of the nonlinear resistance model and the nonlinear inductance model to obtain a voltage transformer model.

9. A voltage transformer model determination apparatus characterized by comprising: It includes: The first acquisition module is used for acquiring measurement voltage effective value data, measurement current effective value data, magnetic flux data and no-load loss curve of a voltage transformer within a preset sampling period, wherein the no-load loss curve is used to indicate the relationship between the measurement voltage effective value data and the corresponding active power data when the voltage transformer is in a no-load running state; The first determination module is used for determining, based on the measurement voltage effective value data and the active power data, nonlinear resistance data of the voltage transformer within the preset sampling period by using a first point-by-point recursive method. The second determining module is configured to determine, based on the nonlinear resistance data, resistance current peak value data of the voltage transformer in the preset sampling period, and a first relationship curve between the nonlinear resistance data and the resistance current peak value data; The third determining module is configured to determine, based on the resistance current peak value data, the measured current effective value data, and the magnetic flux data, nonlinear inductance data of the voltage transformer in the preset sampling period by using a second point-by-point recursion method; The fourth determining module is configured to determine, based on the nonlinear inductance data, inductance current peak value data of the voltage transformer in the preset sampling period, and a second relationship curve between the nonlinear inductance data and the inductance current peak value data; The second obtaining module is configured to perform model simulation processing according to the first relationship curve and the second relationship curve to obtain a voltage transformer model.

10. A non-volatile storage medium, characterized by, The nonvolatile storage medium stores a plurality of instructions, and the instructions are adapted to be loaded and executed by the processor to perform the method for determining the voltage transformer model in any one of claims 1 to 8.

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