Equivalent method and related devices for time-harmonic field excitation based on transformer load loss

Abstract

This application discloses a time-harmonic field excitation equivalent method and related apparatus based on transformer load loss, relating to the field of transformers. The method includes: obtaining the equivalent excitation current of the target transformer under DC bias conditions; calculating the equivalent inductance component of the excitation current at power frequency based on the principle of conservation of magnetic field energy; calculating the equivalent resistance component of the excitation current at power frequency based on the principle of conservation of ohmic and eddy current losses; and calculating the load loss and structural component temperature rise of the target transformer in time-harmonic field finite element simulation software based on the equivalent inductance and resistance components of the current. Therefore, this application uses load loss as the equivalent basis, equating the excitation current to the equivalent inductance and resistance components at power frequency, enabling the calculation of structural component temperature rise in time-harmonic field finite element simulation software, which is more time-saving, labor-saving, and convergent, while also reducing resource consumption.

Description

Technical Field

[0001] This application relates to the field of transformers, and more particularly to an equivalent method and apparatus for time-harmonic field excitation based on transformer load loss. Background Technology

[0002] Geomagnetic storms and the asymmetrical operation of unipolar DC transmission projects are the main causes of DC bias in transformers. DC bias causes a sharp increase in excitation saturation, leading to asymmetry in the core flux, which in turn results in an unbalanced transformer magnetic circuit, a significant increase in leakage flux, and affects transformer losses, temperature rise, and noise. In severe cases, it can even cause transformer insulation damage, triggering serious faults and directly threatening the safe operation of the power system. Therefore, studying the impact of DC bias on transformer load losses and temperature rise is of great significance.

[0003] Under DC bias conditions, the transformer's excitation current contains a fundamental wave and a large number of harmonic components of different orders. Its waveform is a non-sinusoidal, asymmetrical, spiked wave, meaning the excitation current can only be calculated using transient field finite element simulation software to obtain the temperature rise of the transformer's structural components. However, this method is time-consuming and labor-intensive, and the transient field solution process is difficult to converge, potentially preventing the acquisition of the required load losses and structural component temperature rise values. Summary of the Invention

[0004] In view of the above problems, this application provides an equivalent method and related apparatus for time-harmonic field excitation based on transformer load loss, so as to obtain the load loss and structural temperature rise of the target transformer based on the excitation current in time-harmonic field finite element simulation software. The specific scheme is as follows:

[0005] The first aspect of this application provides an equivalent method for time-harmonic field excitation based on transformer load losses, including:

[0006] Obtain the equivalent excitation current of the target transformer under DC bias conditions;

[0007] Based on the principle of conservation of magnetic field energy, the inductance component of the excitation current at the power frequency is calculated as the equivalent current inductance component.

[0008] Based on the principle of conservation of ohmic loss and eddy current loss, the equivalent excitation current to be equivalent to the excitation current resistance component at the power frequency is calculated and used as the equivalent current resistance component.

[0009] Based on the equivalent current inductance component and the equivalent current resistance component, the load loss and structural temperature rise of the target transformer are calculated in the time-harmonic field finite element simulation software.

[0010] In one possible implementation, obtaining the equivalent excitation current of the target transformer under DC bias conditions includes:

[0011] Obtain the basic parameter values ​​of the target transformer, and call the pre-generated excitation current calculation program to determine the equivalent excitation current based on the basic parameter values;

[0012] And / or, acquire the on-site current waveform data of the target transformer, and obtain the equivalent excitation current to be obtained based on the on-site current waveform data.

[0013] In one possible implementation, calculating the equivalent excitation current inductance component at power frequency based on the principle of conservation of magnetic field energy includes:

[0014] Based on the aforementioned magnetic field energy conservation equivalence principle, the first function of the fundamental frequency and each order harmonic of the transformer excitation current and the inductive component of the equivalent power frequency excitation current is determined.

[0015] The first function is rewritten using the fundamental frequency correction factor and the harmonic correction factors of each order to obtain the corrected function;

[0016] Determine the fundamental component and harmonic components of the equivalent excitation current.

[0017] Obtain the correction coefficient values ​​for each component of the equivalent excitation current to be obtained, wherein all components include the fundamental component and the harmonic components of each order.

[0018] Substituting the fundamental component and harmonic components of the current to be equivalent to the current to be equivalent to the current to be equivalent to the inductive component of the current at the power frequency into the corrected function, we obtain the current to be equivalent to ...

[0019] In one possible implementation, calculating the equivalent excitation current resistance component at the power frequency based on the equivalence principle of ohmic loss and eddy current loss conservation includes:

[0020] Based on the aforementioned equivalence principle of conservation of ohmic loss and eddy current loss, the second function of the fundamental frequency and each order harmonic of the transformer excitation current and the resistance component of the equivalent power frequency excitation current is determined.

[0021] Determine the fundamental component and harmonic components of the equivalent excitation current.

[0022] Substituting the fundamental component and harmonic components of the excitation current to be equivalent into the second function, the excitation current resistance component at the power frequency is obtained.

[0023] In one possible implementation, determining the fundamental component and harmonic components of the equivalent excitation current includes:

[0024] Perform a Fourier transform on the current to be equivalently excited to obtain the fundamental component and harmonic components of the current to be equivalently excited.

[0025] In one possible implementation, calculating the load loss and structural temperature rise of the target transformer in time-harmonic finite element simulation software based on the equivalent current inductance component and the equivalent current resistance component includes:

[0026] The target equivalent power frequency excitation current is determined based on the equivalent current inductance component and the equivalent current resistance component.

[0027] The target equivalent power frequency excitation current is determined as the excitation source of the solver in the time-harmonic field finite element simulation software, and the load loss and structural component temperature rise of the target transformer are calculated based on the solver.

[0028] A second aspect of this application provides an equivalent device for time-harmonic field excitation based on transformer load losses, comprising:

[0029] The current acquisition module is used to acquire the equivalent excitation current of the target transformer under DC bias conditions.

[0030] The inductance equivalent module is used to calculate the inductance component of the excitation current at the power frequency based on the principle of conservation of magnetic field energy, and use it as the inductance component of the equivalent current.

[0031] The resistance equivalent module is used to calculate the equivalent current resistance component of the excitation current at the power frequency based on the conservation and equivalence principle of ohmic loss and eddy current loss, and to use it as the equivalent current resistance component.

[0032] The temperature rise calculation module is used to calculate the load loss and structural temperature rise of the target transformer in the time-harmonic field finite element simulation software based on the equivalent current inductance component and the equivalent current resistance component.

[0033] A third aspect of this application provides a computer program product including computer-readable instructions that, when executed on an electronic device, cause the electronic device to implement the equivalent method of time-harmonic field excitation based on transformer load loss as described in the first aspect or any implementation thereof.

[0034] A fourth aspect of this application provides an electronic device, comprising at least one processor and a memory connected to the processor, wherein:

[0035] The memory is used to store computer programs;

[0036] The processor is used to execute the computer program so that the electronic device can implement the equivalent method of time-harmonic field excitation based on transformer load loss in the first aspect or any implementation thereof.

[0037] The fifth aspect of this application provides a computer storage medium carrying one or more computer programs, which, when executed by an electronic device, enable the electronic device to implement the equivalent method of time-harmonic field excitation based on transformer load loss as described in the first aspect or any implementation thereof.

[0038] Using the above technical solution, this application provides a time-harmonic field excitation equivalent method based on transformer load loss to obtain the equivalent excitation current of the target transformer under DC bias conditions. Considering that changes in the inductive component of the excitation current under DC bias conditions will cause changes in the magnetic field, thus affecting the distribution and energy of the leakage magnetic field, this application can calculate the equivalent excitation current inductive component at power frequency based on the principle of magnetic field energy conservation, as the equivalent current inductive component. Simultaneously, since changes in core saturation and flux distribution under DC bias conditions will cause distortion of the current in the windings and the magnetic flux in the core, resulting in changes in the resistance losses (including ohmic losses and eddy current losses) in the windings, this application can also calculate the equivalent excitation current resistance component at power frequency based on the principle of ohmic loss and eddy current loss conservation, as the equivalent current resistance component. Finally, this application can calculate the load loss and structural temperature rise of the target transformer in time-harmonic field finite element simulation software based on the equivalent current inductive component and equivalent current resistance component. Therefore, this application can convert the excitation current containing the fundamental wave and a large number of harmonic components of different orders into equivalent current inductance components and equivalent current resistance components at the power frequency. This allows the application to be simulated in time-harmonic field finite element simulation software for magnetic fields and coupled thermal fields, which is more time-saving, labor-saving and easy to converge. In addition, it reduces resource consumption. Attached Figure Description

[0039] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent when taken in conjunction with the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the originals and elements are not necessarily drawn to scale.

[0040] Figure 1 A schematic diagram of a system architecture is provided for this application;

[0041] Figure 2 A schematic diagram of an optional hardware structure for the terminal 100 provided in this application;

[0042] Figure 3 This application provides a schematic diagram of the structure of a server 200;

[0043] Figure 4 A flowchart illustrating an equivalent method for time-harmonic field excitation based on transformer load loss provided in this application;

[0044] Figure 5 A schematic diagram of the transformer excitation current under 1A DC bias.

[0045] Figure 6 The T-type equivalent circuit diagram of the target transformer;

[0046] Figure 7 A schematic diagram showing the proportion of each order harmonic of the transformer excitation current under 1A DC bias.

[0047] Figure 8 A schematic diagram of the structure of an equivalent device for time-harmonic field excitation based on transformer load loss provided in this application;

[0048] Figure 9 This is a schematic diagram of the structure of an electronic device provided in this application. Detailed Implementation

[0049] The embodiments of this application are described below with reference to the accompanying drawings. The terminology used in the implementation section of this application is for explaining specific embodiments only and is not intended to limit the scope of this application.

[0050] The embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0051] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to those processes, methods, products, or apparatuses.

[0052] See Figure 1 , Figure 1A schematic diagram of a system architecture is shown. The system may include a terminal 100 and a server 200. The server 200 may include one or more servers (…). Figure 1 (The example includes a server), and the server 200 can provide the method provided in the embodiments of this application to one or more terminals.

[0053] The terminal 100 may have an application installed on it. The application and webpage can provide an interface. The terminal 100 can receive relevant parameters input by the user on the interface and send the parameters to the server 200. The server 200 can obtain the processing result based on the received parameters and return the processing result to the terminal 100.

[0054] It should be understood that in some optional implementations, the terminal 100 can also complete the action of obtaining the processing result based on the received parameters on its own, without the need for the server to cooperate. This application embodiment is not limited to this.

[0055] The following description Figure 1 The product form of the mid-terminal 100;

[0056] The terminal 100 in this application embodiment can be a mobile phone, tablet computer, wearable device, vehicle device, augmented reality (AR) / virtual reality (VR) device, laptop computer, ultra-mobile personal computer (UMPC), netbook, personal digital assistant (PDA), etc., and this application embodiment does not impose any restrictions on it.

[0057] Figure 2 A schematic diagram of an optional hardware structure for terminal 100 is shown.

[0058] refer to Figure 2 As shown, the terminal 100 may include a radio frequency unit 110, a memory 120, an input unit 130, a display unit 140, a camera 150 (optional), an audio circuit 160 (optional), a speaker 161 (optional), a microphone 162 (optional), a headphone jack 163 (optional), a processor 170, an external interface 180, a power supply 190, and other components. Those skilled in the art will understand that... Figure 2 These are merely examples of terminals or multi-functional devices and do not constitute a limitation on terminals or multi-functional devices. They may include more or fewer components than shown in the illustration, or combine certain components, or use different components.

[0059] The input unit 130 can be used to receive input numerical or character information, and to generate key signal inputs related to user settings and function control of the portable multi-functional device. Specifically, the input unit 130 may include a touchscreen 131 (optional) and / or other input devices 132. The touchscreen 131 can collect touch operations performed by the user on or near it (such as operations performed by the user using fingers, knuckles, styluses, or any suitable object on or near the touchscreen), and drive the corresponding connection devices according to a pre-set program. The touchscreen can detect the user's touch actions, convert the touch actions into touch signals and send them to the processor 170, and can receive and execute commands sent by the processor 170; the touch signal includes at least touch point coordinate information. The touchscreen 131 can provide an input interface and an output interface between the terminal 100 and the user. In addition, various types of touchscreens, such as resistive, capacitive, infrared, and surface acoustic wave, can be used to implement the touchscreen. Besides the touchscreen 131, the input unit 130 may also include other input devices. Specifically, other input devices 132 may include, but are not limited to, one or more of the following: physical keyboard, function keys (such as volume control buttons, power buttons, etc.), trackball, mouse, joystick, etc.

[0060] Among them, the input device 132 can receive input data, etc.

[0061] The display unit 140 can be used to display information input by the user or information provided to the user, various menus of the terminal 100, interactive interfaces, file display, and / or playback of any multimedia file.

[0062] The memory 120 can be used to store instructions and data. The memory 120 may primarily include an instruction storage area and a data storage area. The data storage area can store various types of data, such as multimedia files and text. The instruction storage area can store software units such as operating systems, applications, and instructions required for at least one function, or subsets or extended sets thereof. It may also include non-volatile random access memory. It provides the processor 170 with hardware, software, and data resources for managing the computing device, supporting control software and applications. It is also used for storing multimedia files, as well as storing running programs and applications.

[0063] The processor 170 is the control center of the terminal 100. It connects various parts of the terminal 100 via various interfaces and lines. By running or executing instructions stored in the memory 120 and calling data stored in the memory 120, it performs various functions and processes data of the terminal 100, thereby controlling the terminal device as a whole. Optionally, the processor 170 may include one or more processing units; preferably, the processor 170 may integrate an application processor and a modem processor, wherein the application processor mainly handles the operating system, user interface, and applications, and the modem processor mainly handles wireless communication. It is understood that the modem processor may not be integrated into the processor 170. In some embodiments, the processor and memory can be implemented on a single chip; in some embodiments, they can also be implemented separately on independent chips. The processor 170 can also be used to generate corresponding operation control signals, send them to the corresponding components of the computing processing device, read and process data in the software, especially read and process data and programs in the memory 120, so that the various functional modules therein perform corresponding functions, thereby controlling the corresponding components to act according to the instructions.

[0064] The memory 120 can be used to store software code related to the time-harmonic field excitation equivalent method based on transformer load loss. The processor 170 can execute the steps of the time-harmonic field excitation equivalent method based on transformer load loss, and can also schedule other units (such as the above-mentioned input unit 130 and display unit 140) to achieve the corresponding functions.

[0065] The radio frequency unit 110 (optional) can be used for receiving and transmitting signals during information transmission or calls. For example, it can receive downlink information from the base station and process it for the processor 170; additionally, it can transmit uplink data to the base station. Typically, the RF circuit includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low-noise amplifier (LNA), a duplexer, etc. Furthermore, the radio frequency unit 110 can also communicate wirelessly with network devices and other devices. This wireless communication can use any communication standard or protocol, including but not limited to Global System for Mobile Communication (GSM), General Packet Radio Service (GPRS), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE), email, Short Messaging Service (SMS), etc.

[0066] In this embodiment of the application, the radio frequency unit 110 can send data to the server 200 and receive the processing results sent by the server 200.

[0067] It should be understood that the radio frequency unit 110 is optional and can be replaced with other communication interfaces, such as a network port.

[0068] The terminal 100 also includes a power supply 190 (such as a battery) that supplies power to various components. Preferably, the power supply can be logically connected to the processor 170 through a power management system, thereby enabling functions such as charging, discharging, and power consumption management through the power management system.

[0069] Terminal 100 also includes an external interface 180, which can be a standard Micro USB interface or a multi-pin connector, which can be used to connect terminal 100 to other devices for communication or to connect a charger to charge terminal 100.

[0070] Although not shown, terminal 100 may also include a flash, a Wireless Fidelity (WiFi) module, a Bluetooth module, sensors with various functions, etc., which will not be described in detail here. Some or all of the methods described below can be applied to, for example... Figure 2 In the terminal 100 shown.

[0071] The following description Figure 1 The product form of the mid-range server 200;

[0072] Figure 3 A structural diagram of a server 200 is provided, as follows: Figure 3 As shown, server 200 includes bus 201, processor 202, communication interface 203, and memory 204. Processor 202, memory 204, and communication interface 203 communicate with each other via bus 201.

[0073] Bus 201 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 3 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0074] The processor 202 can be any one or more of the following processors: a central processing unit (CPU), a graphics processing unit (GPU), a microprocessor (MP), or a digital signal processor (DSP).

[0075] Memory 204 may include volatile memory, such as random access memory (RAM). Memory 204 may also include non-volatile memory, such as read-only memory (ROM), flash memory, hard disk drive (HDD), or solid state drive (SSD).

[0076] The memory 204 can be used to store software code related to the time-harmonic field excitation equivalent method based on transformer load loss. The processor 202 can execute the steps of the chip's time-harmonic field excitation equivalent method based on transformer load loss, and can also schedule other units to achieve the corresponding functions.

[0077] It should be understood that the aforementioned terminal 100 and server 200 can be centralized or distributed devices. The processors (e.g., processor 170 and processor 202) in the aforementioned terminal 100 and server 200 can be hardware circuits (such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), general-purpose processors, DSPs, microprocessors, or microcontrollers, etc.) or combinations of these hardware circuits. For example, the processor can be a hardware system with instruction execution capabilities, such as a CPU or DSP, or a hardware system without instruction execution capabilities, such as an ASIC or FPGA, or a combination of the aforementioned hardware systems without instruction execution capabilities and hardware systems with instruction execution capabilities.

[0078] This application provides an equivalent method for time-harmonic field excitation based on transformer load losses. The following detailed description, in conjunction with the accompanying drawings, provides an embodiment of this application of the equivalent method for time-harmonic field excitation based on transformer load losses.

[0079] Reference Figure 4 , Figure 4 This application provides a flowchart illustrating an equivalent method for time-harmonic field excitation based on transformer load losses. The method may include:

[0080] Step S401: Obtain the equivalent excitation current of the target transformer under DC bias conditions.

[0081] DC bias refers to the presence of a DC component in the excitation current of a transformer. When the target transformer is under DC bias conditions, its excitation current waveform will be distorted, harmonics will be amplified, and the waveform will exhibit non-sinusoidal, asymmetrical, spiked waves, for example... Figure 5 The waveform diagram of the transformer excitation current under 1A DC bias is shown. At time 0.005, the excitation current value increases sharply, exhibiting a non-sinusoidal and asymmetrical spike wave. It is evident that the excitation current of the target transformer under DC bias is crucial for studying its DC bias characteristics.

[0082] The aforementioned target transformer refers to the transformer object studied in this application. For example, the basic parameter values ​​of the target transformer studied in this application are as follows: power supply voltage U = 317543V, excitation coil turns N = 706, core cross-sectional area S = 11594.99 cm², core window height = 2410 mm, core diameter = 1265 mm, frequency = 50 Hz, transformer load loss (rated) = 1248675 W, and transformer impedance (rated) = 14%. Taking the transformer structural component loss calculation under 1A DC bias as an example, the harmonic order is 31.

[0083] It should be noted that the above basic parameter values ​​are merely examples and are not intended to limit this application.

[0084] For ease of subsequent explanation, this application defines the excitation current of the target transformer under DC bias conditions as the equivalent excitation current to be obtained.

[0085] As described in the background section, the aforementioned equivalent excitation current is a non-sinusoidal waveform containing a fundamental component and multiple harmonic components of different orders. This waveform cannot be realized in the solution of time-harmonic fields and can only be solved through transient fields. Since the solution of transient fields is time-consuming, laborious, and difficult to fit, in order to solve these problems, the inventors of this case conceived of a way to convert the equivalent excitation current to the power frequency through an equivalent method, so that the converted equivalent current can be used to solve for load losses and structural component temperature rise values ​​in a time-harmonic field.

[0086] See Figure 6 The diagram shown is the T-type equivalent circuit diagram of the target transformer. When a short circuit occurs at one winding terminal of the target transformer (e.g., ...), ... Figure 6 The two circles on the left are connected, causing a short circuit, or Figure 6 When the two circles on the right are connected and a short circuit occurs, Figure 6 The excitation branch component within the dashed box shown (i.e. and The proportion of the partial excitation branch voltage is very small and can be basically ignored. Therefore, the excitation branch voltage can be approximated as equal to the power supply voltage. Figure 6 The equivalent series impedance of the T-type equivalent circuit diagram shown is: That is, we have the following formula (1).

[0087] Formula (1);

[0088] in, This represents the short-circuit impedance value of the target transformer, in ohms (Ω). In practical applications, this short-circuit impedance value can be obtained by testing the target transformer or by calculating based on the basic parameter values ​​mentioned above. The resistive component of the short-circuit impedance of the target transformer, in Ω; This represents the reactance component of the short-circuit impedance of the target transformer, in Ω.

[0089] As can be seen from formula (1), the load loss of the target transformer can be divided into two main categories: resistive loss and inductive loss.

[0090] The magnitude of the resistive losses mentioned above is related to the magnitude of the current flowing through the conductor. Therefore, resistive losses can be divided into coil losses, lead losses, eddy current losses in metal structural components, eddy current losses in iron core laminations, and eddy current losses in leakage magnetic shielding.

[0091] The magnitude of the inductive loss is related to the amount of leakage magnetic field energy stored in the magnetic material components of the target transformer. Therefore, the inductive loss is divided into hysteresis loss in the iron core, hysteresis loss in the magnetic metal structural components, and hysteresis loss in the leakage magnetic shield.

[0092] Based on the above introduction, in order to convert the equivalent excitation current containing the fundamental component and multiple harmonic components of different orders into an equivalent current at the power frequency (for distinction, the equivalent current is defined as the target equivalent power frequency excitation current below), so as to perform harmonic field finite element simulation calculations in magnetic fields and coupled thermal fields with time-saving and low resource consumption, the inventors of this case thought that when performing equivalent excitation under the DC bias magnetization condition of the target transformer, it can be divided into two parts: equivalent resistance loss characteristics and equivalent leakage magnetic field energy.

[0093] Step S402: Based on the principle of conservation of magnetic field energy, calculate the equivalent excitation current inductance component at the power frequency and use it as the equivalent current inductance component.

[0094] As described above, this embodiment can perform leakage magnetic field energy equivalence. To this end, this embodiment can, based on the principle of conservation of magnetic field energy, convert the excitation current to be equivalent to the equivalent current inductance component at the power frequency (i.e., the fundamental frequency).

[0095] Here, the principle of conservation of magnetic field energy means that the leakage magnetic field energy under the equivalent excitation current is equal to the leakage magnetic field energy under the equivalent current inductance component. More specifically, the first leakage magnetic field energy obtained based on the equivalent excitation current and the equivalent inductance is equal to the second leakage magnetic field energy obtained based on the equivalent current inductance component and the equivalent inductance.

[0096] It should be understood that the equivalent inductance is the same as that mentioned above. Therefore, in this embodiment, the equivalent inductance can be obtained based on the above formula (1) and the following formulas (2), (3) and (4).

[0097] Based on Joule quantification The calculation formula is:

[0098] Formula (2);

[0099] in, This represents the load loss of the target transformer, measured in watts (W). In practical applications, this load loss can be obtained by testing the target transformer or by calculating based on the basic parameter values ​​mentioned above. This indicates that the load loss of the target transformer has reached The corresponding coil load excitation current.

[0100] Reactant component of the short-circuit impedance of the target transformer The calculation formula is:

[0101] Formula (3).

[0102] Therefore, the formula for calculating the equivalent inductance of the target transformer is as follows:

[0103] Formula (4);

[0104] in, This represents the equivalent inductance of the target transformer, expressed in Henry (H). The reactance component representing the short-circuit impedance of the target transformer The power supply frequency during testing is measured in Hertz (Hz), typically the power frequency of 50Hz or 60Hz.

[0105] Step S403: Based on the principle of conservation of ohmic loss and eddy current loss, calculate the equivalent excitation current resistance component at the power frequency and use it as the equivalent current resistance component.

[0106] Following the above description, this embodiment can also perform equivalent resistance loss characteristics. Therefore, this embodiment can, based on the principle of conservation of ohmic loss and eddy current loss, convert the excitation current to be equivalent to the equivalent current resistance component at power frequency.

[0107] Here, the equivalence principle of conservation of ohmic loss and eddy current loss means that the resistance and eddy current loss under the equivalent excitation current are equal to the resistance and eddy current loss under the equivalent current inductive component.

[0108] Step S404: Calculate the load loss and structural temperature rise of the target transformer in the time-harmonic field finite element simulation software based on the equivalent current inductance component and the equivalent current resistance component.

[0109] As mentioned earlier, the equivalent current inductance component and the equivalent current resistance component are both data obtained at the power frequency. They do not include harmonic components of each order. Therefore, they can be simulated and calculated in time-harmonic field finite element simulation software to obtain the load loss and structural component temperature rise of the target transformer.

[0110] This application provides a time-harmonic field excitation equivalent method based on transformer load loss to obtain the equivalent excitation current of the target transformer under DC bias conditions. Considering that changes in the inductive component of the excitation current under DC bias conditions will cause changes in the magnetic field, thus affecting the distribution and energy of the leakage magnetic field, this application can calculate the equivalent excitation current inductive component at power frequency based on the principle of magnetic field energy conservation, as the equivalent current inductive component. Simultaneously, since changes in core saturation and flux distribution under DC bias conditions will cause distortion of the current in the windings and the magnetic flux in the core, resulting in changes in the resistance losses (including ohmic losses and eddy current losses) in the windings, this application can also calculate the equivalent excitation current resistance component at power frequency based on the principle of ohmic loss and eddy current loss conservation, as the equivalent current resistance component. Finally, this application can calculate the load loss and structural temperature rise of the target transformer in time-harmonic field finite element simulation software based on the equivalent current inductive component and equivalent current resistance component. Therefore, this application can convert the excitation current containing the fundamental wave and a large number of harmonic components of different orders into equivalent current inductance components and equivalent current resistance components at the power frequency. This allows the application to be simulated in time-harmonic field finite element simulation software for magnetic fields and coupled thermal fields, which is more time-saving, labor-saving and easy to converge. In addition, it reduces resource consumption.

[0111] In some embodiments of this application, the process of "obtaining the equivalent excitation current of the target transformer under DC bias conditions" in step S401 is described.

[0112] In one possible implementation, this embodiment can pre-write an excitation current calculation program. When it is necessary to determine the equivalent excitation current, the basic parameter values ​​of the target transformer described above can be obtained, and then the pre-generated excitation current calculation program can be called to determine the equivalent excitation current based on the basic parameter values. More specifically, the basic parameter values ​​are substituted into the excitation current calculation program to obtain the equivalent excitation current.

[0113] In another possible implementation, this embodiment can also record the on-site current waveform data of the target transformer using a waveform recording device. In this case, the equivalent excitation current can be obtained based on the on-site current waveform data.

[0114] Of course, the process of "obtaining the equivalent excitation current of the target transformer under DC bias conditions" can be achieved in other ways, such as through experiments, and this application does not impose specific limitations.

[0115] Given the equivalent excitation current, this embodiment can obtain the equivalent current inductance component according to step S402 above.

[0116] Optionally, step S402, "calculating the inductive component of the excitation current equivalent to the power frequency based on the principle of conservation of magnetic field energy," may include: determining the first function of the fundamental and harmonic components of the transformer excitation current and the inductive component of the equivalent power frequency excitation current based on the principle of conservation of magnetic field energy; rewriting the first function using the fundamental correction coefficient and the harmonic correction coefficient to obtain the corrected function; determining the fundamental and harmonic components of the excitation current to be equivalent; obtaining the correction coefficient values ​​for all components of the excitation current to be equivalent, including the fundamental component and the harmonic components; substituting the fundamental and harmonic components of the excitation current to be equivalent, as well as the correction coefficient values ​​for all components of the excitation current to be equivalent, into the corrected function to obtain the inductive component of the excitation current equivalent to the power frequency.

[0117] Specifically, those skilled in the art should understand that the leakage magnetic field energy of a transformer is stored through the equivalent leakage inductance. Therefore, in this embodiment, the equivalent inductance of the target transformer... The following relationship exists between the leakage magnetic field energy and the leakage magnetic field energy:

[0118] Formula (5);

[0119] in, This represents the effective value of the alternating current flowing through the target transformer, in amperes (A). This represents the leakage magnetic field energy of the target transformer inductance.

[0120] As previously introduced, the equivalent excitation current under DC bias conditions contains the fundamental frequency and a large number of harmonic components of different orders. Therefore, for excitation by power supplies of different orders of harmonics, the above formula (5) can be transformed into the following formula (6):

[0121] Formula (6);

[0122] in, Indicates j-th order harmonic excitation ( j=1 represents the fundamental excitation, and n represents the total order of the harmonic components to be equivalent. Taking the basic parameter values ​​mentioned above as an example, when n=31), the leakage magnetic field energy stored in the equivalent inductance of the target transformer is expressed in joules (J). This represents the effective value of the j-th order harmonic excitation current flowing through the target transformer, in A.

[0123] Therefore, the total leakage magnetic field energy at all orders The calculation formula is:

[0124] Formula (7).

[0125] The equivalent power frequency excitation current inductance component (i.e., the equivalent power frequency excitation current inductance component at the fundamental frequency, also known as the equivalent power frequency excitation current inductance component at the power frequency) is denoted as... Then, the above formula (5) can also be transformed into the following formula (8):

[0126] Formula (8).

[0127] Therefore, based on the principle of conservation of magnetic field energy, formulas (7) and (8) are equal, and the first function is determined as follows:

[0128] Formula (9).

[0129] This allows for the determination of the fundamental frequency of the transformer excitation current based on the principle of conservation of magnetic field energy. and harmonics of all orders ~ With the inductive component of the equivalent power frequency excitation current The first function.

[0130] Considering that the loss characteristic curves of magnetic materials stored in the material library in the magnetic field finite element simulation software are usually obtained by testing under power frequency excitation conditions, but as the frequency increases, the increase in hysteresis loss of magnetic materials is proportional to the increase in frequency. Therefore, it is necessary to introduce corresponding loss correction coefficients in the equivalent transformation of each order harmonic current. That is, in this embodiment, it is also necessary to rewrite the first function shown in formula (9) by using the fundamental correction coefficient and the correction coefficients of each order harmonic to obtain the corrected function, as shown in formula (10) below:

[0131] Formula (10);

[0132] in, The j-th order harmonic correction factor (j=1 represents the fundamental frequency correction factor) is calculated using the following formula:

[0133] Formula (11);

[0134] in, This represents the harmonic influence coefficient, which is optional and has a value between 0.9 and 1. This represents the harmonic order coefficient, which is optional and has a value between 0.07 and 0.09.

[0135] Based on the modified function described above, this embodiment needs to determine the parameter values ​​of each parameter in the modified function so that the parameter values ​​can be substituted into formula (10) to obtain... .

[0136] Based on this, this embodiment can first determine the fundamental component and harmonic components of the equivalent excitation current to be used, i.e., the above-mentioned The value of . Optionally, the process of "determining the fundamental component and harmonic components of the equivalent excitation current" may include: performing a Fourier transform on the equivalent excitation current to obtain the fundamental component and harmonic components of the equivalent excitation current.

[0137] To improve efficiency, the above Fourier transform can optionally be replaced by a Fast Fourier Transform, then the fundamental component and harmonic components of the equivalent excitation current are obtained as follows: ,here, Indicates the equivalent excitation current to be determined. This represents the fundamental component of the equivalent excitation current. ~ This represents the harmonic components of the equivalent excitation current.

[0138] See Figure 7 This is a schematic diagram showing the percentage of harmonics in the transformer excitation current under 1A DC bias. It can be seen that as the order gradually increases, the percentage of harmonics gradually decreases.

[0139] This embodiment can also obtain the correction coefficient values ​​for each component of the equivalent excitation current, wherein the correction coefficient value for any component can be obtained by acquiring the above-mentioned correction coefficient values. and Calculated.

[0140] Finally, in this embodiment, the fundamental component and harmonic components of the equivalent excitation current, as well as the correction coefficients of all components of the equivalent excitation current, can be substituted into the corrected function, that is, Substituting into formula (10) ,Will Substituting into formula (10) And so on, substituting the correction coefficient values ​​of each component into formula (10). This allows us to obtain the equivalent excitation current inductance component at the power frequency, i.e., the equivalent current inductance component. .

[0141] like Figure 4 As shown in the process, in this embodiment, the equivalent current resistance component can also be obtained by following step S403 above.

[0142] Optionally, step S403, "calculating the equivalent excitation current resistance component at power frequency based on the equivalence principle of ohmic loss and eddy current loss conservation," may include: determining the second function of the fundamental and harmonic components of the transformer excitation current and the equivalent power frequency excitation current resistance component based on the equivalence principle of ohmic loss and eddy current loss conservation; determining the fundamental and harmonic components of the excitation current to be equivalent; and substituting the fundamental and harmonic components of the excitation current to be equivalent into the second function to obtain the equivalent excitation current resistance component at power frequency.

[0143] Specifically, those skilled in the art should understand that when a load current flows through, the resistance loss can be divided into direct resistance loss (including coil loss and lead loss) caused by the pure current flow and indirect eddy current loss (including eddy current loss in metal structural components, eddy current loss in iron core sheets and eddy current loss in leakage magnetic shielding) caused by the magnetic field change caused by the load current.

[0144] For direct resistive losses, coil losses and lead losses are characterized as losses generated by current flowing through the resistor, and the equivalent power of the linear circuit can be characterized as the heating of the resistor. Therefore, the following formula (12) holds:

[0145] Formula (12);

[0146] in, Indicates direct resistance loss; This represents the total equivalent resistance, expressed in Ω. , Indicates the equivalent resistance of the coil. Indicates the linear equivalent resistance; This represents the effective value of the alternating current flowing through the target transformer, in amperes (A).

[0147] Regarding indirect resistance losses, when there is current The leakage magnetic field strength generated by indirect resistive loss when flowing through It can be represented as:

[0148] Formula (13);

[0149] in, This indicates the number of coil turns, in turns. Represents the Lochte coefficient; Indicates the coil reactance height; This represents the effective value of the alternating current flowing through the target transformer, in amperes (A).

[0150] Therefore, the eddy current loss generated by leakage flux in its structural components can be expressed as:

[0151] Formula (14);

[0152] in, Indicates indirect resistance loss; This represents the eddy current loss coefficient, and its value depends on the properties of the magnetic material. Indicates the reversal frequency of the magnetic field; Indicates conductor thickness; Indicates the magnetic permeability of a conductor; Indicates the volume of the magnetic material; Indicates magnetic flux density. .

[0153] make Then formula (14) can be further simplified to:

[0154] Formula (15).

[0155] As mentioned earlier, the magnetic field energy equivalence that determines resistive losses is based on the energy equivalence method. It considers the energy representation of coil losses, lead losses, eddy current losses in metal structural components, eddy current losses in core laminations, and eddy current losses in leakage magnetic shielding as the heating power of the resistor. Therefore, according to the previous statement:

[0156] Formula (16);

[0157] in, This represents the resistance and eddy current loss generated by the equivalent resistance of the target transformer. Indicates the equivalent coefficient; This represents the effective value of the alternating current flowing through the target transformer, in amperes (A).

[0158] As previously introduced, the equivalent excitation current under DC bias conditions contains the fundamental frequency and a large number of harmonic components of different orders. Therefore, for excitation by power supplies of different orders of harmonics, the above formula (16) can be transformed into the following formula (17):

[0159] Formula (17);

[0160] in, Indicates j-th order harmonic excitation ( j=1 indicates fundamental excitation, and n indicates the total order of the harmonic components to be equivalent. Taking the basic parameter values ​​mentioned above as an example, when n=31), the resistance and eddy current loss generated by the equivalent resistance of the target transformer are expressed in J. This represents the effective value of the j-th order harmonic excitation current flowing through the target transformer, in A.

[0161] Therefore, the formulas for calculating the resistance and total eddy current loss at all orders are as follows:

[0162] Formula (18).

[0163] The equivalent power frequency excitation current resistance component (i.e., the equivalent power frequency excitation current resistance component at the fundamental frequency, also known as the equivalent power frequency excitation current resistance component at the power frequency) is denoted as... Then the above formula (16) can also be transformed into the following formula (19):

[0164] Formula (19).

[0165] Therefore, based on the principle of conservation equivalence between ohmic loss and eddy current loss, the above formulas (18) and (19) are equal, and the determined second function is as follows:

[0166] Formula (20).

[0167] This allows for the determination of the fundamental frequency of the transformer excitation current based on the equivalence principle of conservation of Ohmic loss and eddy current loss. and harmonics of all orders ~ With the equivalent power frequency excitation current resistance component The second function.

[0168] Since resistive loss does not change with increasing frequency, no rewriting is needed. This second function is the function to be calculated using the data. Therefore, based on the second function, this embodiment needs to determine the parameter values ​​of each parameter included in the second function, and substitute these parameter values ​​into formula (20) to obtain... .

[0169] Based on this, this embodiment can first determine the fundamental component and harmonic components of the equivalent excitation current to be used, i.e., the above-mentioned The value of this process corresponds to step S402 in the previous text. For details, please refer to the previous text. It will not be repeated here.

[0170] Finally, in this embodiment, the fundamental component and harmonic components of the equivalent excitation current can be substituted into the second function, that is... Substituting into formula (20) ,Will Substituting into formula (20) By analogy, we can obtain the equivalent excitation current inductive component at the power frequency, which is the equivalent current resistive component. .

[0171] Furthermore, after obtaining the equivalent current inductance component and the equivalent current resistance component, step S404 can be executed.

[0172] Optionally, step S404, "calculating the load loss and structural component temperature rise of the target transformer in the time-harmonic field finite element simulation software based on the equivalent current inductance component and the equivalent current resistance component," may include: determining the target equivalent power frequency excitation current based on the equivalent current inductance component and the equivalent current resistance component; determining the target equivalent power frequency excitation current as the excitation source of the solver in the time-harmonic field finite element simulation software; and calculating the load loss and structural component temperature rise of the target transformer based on the solver.

[0173] Optionally, the target equivalent power frequency excitation current can be determined using the following formula (21). .

[0174] Formula (21).

[0175] The time-harmonic field equivalent excitation source method provided in this application is compared with the transient field finite element method provided in the background art, and the results are shown in the table below.

[0176] method time consuming CPU utilization Convergence characteristics Transient field finite element method 7 days 97% Difficult to control Time-Harmonic Field Equivalent Excitation Source Method 6-7 hours 30% Easy to converge

[0177] Therefore, the time-harmonic equivalent excitation source method provided in this application is more time-efficient, has lower resource consumption, and better convergence performance compared to transient field calculation. This is mainly because, under DC bias conditions, the excitation current of the target transformer is a superposition of multiple frequency harmonic currents, and the waveform also exhibits a certain degree of non-sinusoidal characteristics. This means that when using transient field calculation, it is necessary to perform magnetic field calculations at different frequencies and additional calculations of ineffective fields, leading to a sharp increase in time costs. Secondly, transient field calculations prevent the application of the impedance boundary method, greatly increasing the mesh components in finite element calculations and causing resource consumption to rise. Finally, the convergence problems sometimes caused by transient field calculations also consume a great deal of time and resources. The time-harmonic equivalent excitation source method provided in this application can significantly avoid the above problems, transforming the originally time-consuming and resource-intensive transient field finite element simulation problem into a time-efficient and resource-low-consumption time-harmonic field finite element simulation problem, greatly improving computational efficiency.

[0178] The above describes an equivalent method for time-harmonic field excitation based on transformer load loss provided by the embodiments of this application. The following will describe the apparatus for performing the above-described equivalent method for time-harmonic field excitation based on transformer load loss.

[0179] Please see Figure 8 , Figure 8This is a schematic diagram of a time-harmonic field excitation equivalent device based on transformer load loss, provided as an embodiment of this application. Figure 8 As shown, the device may include:

[0180] The current acquisition module 501 is used to acquire the equivalent excitation current of the target transformer under DC bias conditions.

[0181] The inductance equivalent module 502 is used to calculate the inductance component of the excitation current at the power frequency based on the principle of conservation of magnetic field energy, and use it as the inductance component of the equivalent current.

[0182] The resistance equivalent module 503 is used to calculate the equivalent excitation current resistance component at the power frequency based on the conservation and equivalence principle of ohmic loss and eddy current loss, and use it as the equivalent current resistance component.

[0183] The temperature rise calculation module 504 is used to calculate the load loss and structural temperature rise of the target transformer in the time-harmonic field finite element simulation software based on the equivalent current inductance component and the equivalent current resistance component.

[0184] In one possible implementation, the aforementioned current acquisition module can be used to: acquire the basic parameter values ​​of the target transformer, call a pre-generated excitation current calculation program to determine the equivalent excitation current based on the basic parameter values; and / or acquire the on-site current waveform data of the target transformer, and obtain the equivalent excitation current based on the on-site current waveform data.

[0185] In one possible implementation, the above-mentioned inductance equivalent module may include: a first function determination module, a function rewriting module, a first component determination module, a correction coefficient value acquisition module, and a first numerical substitution module;

[0186] The first function determination module is used to determine the first function of the fundamental wave and harmonics of the transformer excitation current and the inductive component of the equivalent power frequency excitation current, based on the principle of conservation of magnetic field energy.

[0187] The function rewriting module is used to rewrite the first function using the fundamental correction coefficient and the correction coefficients of each order of harmonics to obtain the corrected function;

[0188] The first component determination module is used to determine the fundamental component and harmonic components of the equivalent excitation current.

[0189] The correction coefficient value acquisition module is used to acquire the correction coefficient values ​​of each component of the equivalent excitation current to be obtained. All components include the fundamental component and harmonic components of each order.

[0190] The first numerical substitution module is used to substitute the fundamental component and harmonic components of the current to be equivalent to into the corrected function, as well as the correction coefficient values ​​of all components of the current to be equivalent to, into the corrected function, so as to obtain the inductance component of the current to be equivalent to at the power frequency.

[0191] In one possible implementation, the above-mentioned resistance equivalent module may include: a second function determination module, a second component determination module, and a second value substitution module;

[0192] The second function determination module is used to determine the second function of the fundamental frequency and harmonics of the transformer excitation current and the equivalent power frequency excitation current resistance component based on the equivalence principle of conservation of ohmic loss and eddy current loss.

[0193] The second component determination module is used to determine the fundamental component and harmonic components of the equivalent excitation current.

[0194] The second numerical substitution module is used to substitute the fundamental component and harmonic components of the excitation current to be equivalent into the second function to obtain the excitation current resistance component at the power frequency.

[0195] In one possible implementation, the process by which the first component determination module and the second component determination module each determine the fundamental component and harmonic components of the equivalent excitation current may include: performing a Fourier transform on the equivalent excitation current to obtain the fundamental component and harmonic components of the equivalent excitation current.

[0196] In one possible implementation, the temperature rise calculation module may include a current equivalent module and a time harmonic field calculation module.

[0197] The current equivalent module is used to determine the target equivalent power frequency excitation current based on the equivalent current inductance component and the equivalent current resistance component.

[0198] The time-harmonic field calculation module is used to determine the target equivalent power frequency excitation current as the excitation source of the solver in the time-harmonic field finite element simulation software, and calculate the load loss and structural component temperature rise of the target transformer based on the solver.

[0199] The time-harmonic field excitation equivalent device based on transformer load loss provided in this application corresponds to the time-harmonic field excitation equivalent method based on transformer load loss provided above. For details, please refer to the above introduction, which will not be repeated here.

[0200] This application also provides an electronic device in its embodiments. (See reference...) Figure 9The diagram illustrates a structural schematic suitable for implementing the electronic device in the embodiments of this application. The electronic device in the embodiments of this application may include, but is not limited to, fixed terminals such as mobile phones, laptops, PDAs (personal digital assistants), PADs (tablet computers), desktop computers, etc. Figure 9 The electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0201] like Figure 9 As shown, the electronic device may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 601, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from a storage device 608 into a random access memory (RAM) 603. When the electronic device is powered on, the RAM 603 also stores various programs and data required for the operation of the electronic device. The processing unit 601, ROM 602, and RAM 603 are interconnected via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0202] Typically, the following devices can be connected to I / O interface 605: input devices 606 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 607 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 608 including, for example, memory cards, hard drives, etc.; and communication devices 609. Communication device 609 allows electronic devices to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 9 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown. More or fewer devices may be implemented or have alternatively.

[0203] This application also provides a computer program product including computer-readable instructions, which, when executed on an electronic device, cause the electronic device to implement any of the time-harmonic field excitation equivalent methods based on transformer load loss provided in this application.

[0204] This application also provides a computer-readable storage medium carrying one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can implement any of the time-harmonic field excitation equivalent methods based on transformer load loss provided in this application.

[0205] It should also be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. In addition, in the device embodiment drawings provided in this application, the connection relationship between modules indicates that they have a communication connection, which can be implemented as one or more communication buses or signal lines.

[0206] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware, or it can be implemented by special-purpose hardware including application-specific integrated circuits, special-purpose CPUs, special-purpose memory, special-purpose components, etc. Generally, any function performed by a computer program can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be diverse, such as analog circuits, digital circuits, or special-purpose circuits. However, for this application, software program implementation is more often the preferred implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a readable storage medium, such as a computer floppy disk, USB flash drive, mobile hard disk, ROM, RAM, magnetic disk, or optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, training equipment, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0207] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product.

[0208] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from one website, computer, training device, or data center to another website, computer, training device, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

Claims

1. A time-harmonic field excitation equivalent method based on transformer load loss, characterized in that, The method comprises the following steps: obtaining an excitation current to be equivalent under a DC bias condition of a target transformer; calculating, according to a magnetic field energy conservation equivalent principle, an inductance component of the excitation current under a power frequency, as an equivalent current inductance component, by equivalent of the excitation current to be equivalent; calculating, according to an Ohm loss and eddy current loss conservation equivalent principle, a resistance component of the excitation current under the power frequency, as an equivalent current resistance component, by equivalent of the excitation current to be equivalent; calculating, according to the equivalent current inductance component and the equivalent current resistance component, a load loss and a structure temperature rise value of the target transformer in a time-harmonic field finite element simulation software; wherein the calculating, according to the magnetic field energy conservation equivalent principle, of the inductance component of the excitation current under the power frequency by equivalent of the excitation current to be equivalent comprises: determining, according to the magnetic field energy conservation equivalent principle, a first function of a fundamental wave and each harmonic wave of a transformer excitation current and an equivalent power frequency excitation current inductance component; rewriting the first function through a fundamental wave correction coefficient and each harmonic wave correction coefficient to obtain a corrected function; determining a fundamental wave component and each harmonic wave component of the excitation current to be equivalent; obtaining a correction coefficient value of each component of the excitation current to be equivalent, wherein the components include the fundamental wave component and the each harmonic wave component; substituting the fundamental wave component and the each harmonic wave component of the excitation current to be equivalent and the correction coefficient value of each component of the excitation current to be equivalent into the corrected function to obtain the inductance component of the excitation current under the power frequency by equivalent of the excitation current to be equivalent.

2. The transformer load loss based time harmonic field excitation equivalent method of claim 1, wherein, The obtaining of the excitation current to be equivalent under the DC bias condition of the target transformer comprises: obtaining a basic parameter value of the target transformer, calling a pre-generated excitation current calculation program to determine the excitation current to be equivalent according to the basic parameter value; and / or, obtaining current field recording data of the target transformer, and obtaining the excitation current to be equivalent based on the current field recording data.

3. The transformer load loss based time harmonic field excitation equivalent method of claim 1, wherein, The calculating, according to the Ohm loss and eddy current loss conservation equivalent principle, of the resistance component of the excitation current under the power frequency by equivalent of the excitation current to be equivalent comprises: determining, according to the Ohm loss and eddy current loss conservation equivalent principle, a second function of a fundamental wave and each harmonic wave of a transformer excitation current and an equivalent power frequency excitation current resistance component; determining a fundamental wave component and each harmonic wave component of the excitation current to be equivalent; substituting the fundamental wave component and the each harmonic wave component of the excitation current to be equivalent into the second function to obtain the resistance component of the excitation current under the power frequency by equivalent of the excitation current to be equivalent.

4. The transformer load loss based time-harmonic field excitation equivalent method according to claim 1 or 3, characterized in that, The determining of the fundamental wave component and the each harmonic wave component of the excitation current to be equivalent comprises: performing Fourier transform on the excitation current to be equivalent to obtain the fundamental wave component and the each harmonic wave component of the excitation current to be equivalent.

5. The transformer load loss based time harmonic field excitation equivalent method of claim 1, wherein, The calculating, according to the equivalent current inductance component and the equivalent current resistance component, of the load loss and the structure temperature rise value of the target transformer in the time-harmonic field finite element simulation software comprises: determining a target equivalent power frequency excitation current according to the equivalent current inductance component and the equivalent current resistance component; The target equivalent power frequency excitation current is determined as an excitation source of a solver in the time-harmonic field finite element simulation software, and the load loss and structure temperature rise value of the target transformer are calculated according to the solver.

6. A time-harmonic field excitation equivalent based on transformer load loss, characterized by, The method comprises the steps of: The current acquisition module is configured to acquire a to-be-equivalent excitation current of a target transformer under a direct current bias magnetizing condition. The inductance equivalent module is configured to calculate, according to a magnetic field energy conservation equivalent principle, an inductance component of the to-be-equivalent excitation current equivalent to an excitation current under a power frequency, as an equivalent current inductance component. The resistance equivalent module is configured to calculate, according to an Ohm loss and eddy current loss conservation equivalent principle, a resistance component of the to-be-equivalent excitation current equivalent to the excitation current under the power frequency, as an equivalent current resistance component. The temperature rise calculation module is configured to calculate, according to the equivalent current inductance component and the equivalent current resistance component, the load loss and structure temperature rise value of the target transformer in the time-harmonic field finite element simulation software. According to the magnetic field energy conservation equivalent principle, the inductance equivalent module calculates the inductance component of the to-be-equivalent excitation current equivalent to the excitation current under the power frequency, which comprises the steps of: According to the magnetic field energy conservation equivalent principle, a first function of a fundamental wave and each harmonic wave of the transformer excitation current and an equivalent power frequency excitation current inductance component is determined; the first function is rewritten through a fundamental wave correction coefficient and a harmonic wave correction coefficient to obtain a corrected function; a fundamental wave component and each harmonic wave component of the to-be-equivalent excitation current are determined; a correction coefficient value of each of all components of the to-be-equivalent excitation current is acquired, wherein the all components include the fundamental wave component and the harmonic wave component; the fundamental wave component and each harmonic wave component of the to-be-equivalent excitation current and the correction coefficient value of each of all components of the to-be-equivalent excitation current are substituted into the corrected function to obtain the inductance component of the to-be-equivalent excitation current equivalent to the excitation current under the power frequency.

7. A computer program product, characterised in that, The computer readable instructions, when executed on an electronic device, cause the electronic device to implement the time-harmonic field excitation equivalent method based on transformer load loss according to any one of claims 1 to 5.

8. An electronic device, comprising: The memory is configured to store a computer program. The processor is configured to execute the computer program to enable the electronic device to implement the time-harmonic field excitation equivalent method based on transformer load loss according to any one of claims 1 to 5. The storage medium carries one or more computer programs, which, when executed by an electronic device, enable the electronic device to implement the time-harmonic field excitation equivalent method based on transformer load loss according to any one of claims 1 to 5.

9. A computer storage medium, characterized in that ​

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