A method and system for modeling the load frequency response of an induction motor

Abstract

The application relates to the technical field of power grid frequency response, and discloses an induction motor load frequency response modeling method and system. The method is characterized in that the structure of an induction motor is circuit-equivalent, and power flow calculation is performed on the induction motor; the current slip of the induction motor is updated by using the power flow calculation result of the load node of the induction motor, so that the current slip of the induction motor meets the slip threshold, the error of frequency simulation analysis of a large power grid is reduced, the active power consumed by the load node of the induction motor is determined by using the updated current slip, a load frequency response model about the active power consumed by the load node of the induction motor and the system frequency is constructed, and the accuracy of the load frequency response of the induction motor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid frequency response, and in particular to a method and system for modeling an induction motor load frequency response model. Background Art

[0002] For frequency analysis and calculation, frequency response models of equipment are established, such as the speed regulator and prime mover model of the synchronous machine, the FLC control model of the DC equipment, and the frequency modulation control model of the new energy equipment. The system moment of inertia is established, and the frequency change trend is analyzed based on the system active power fluctuation. Compared with traditional electromechanical or electromagnetic transient simulation, it has the advantages of fast simulation speed and no need for grid information. It is often used in power grid frequency security and stability analysis.

[0003] There are many types of loads, including static and dynamic load models. Static load models include constant impedance, constant power, and constant current loads, while dynamic load models primarily target induction motor loads. To facilitate rapid analysis of system frequency, frequency response models are generally considered only for static loads. However, with advances in load modeling and forecasting technology, unlike static loads, the active power consumed by motor loads is related not only to the voltage amplitude at the load node but also to the system frequency. This can easily lead to significant errors in frequency simulation analysis of actual large power grids, resulting in low accuracy. Summary of the Invention

[0004] In view of this, the present invention provides a method and system for modeling an induction motor load frequency response model, which solves the technical problems of large errors in frequency simulation analysis of large power grids and low accuracy of simulation analysis.

[0005] A first aspect of the present invention provides a method for modeling an induction motor load frequency response model, comprising:

[0006] The structure of the induction motor is subjected to circuit equivalence to obtain an equivalent circuit model;

[0007] performing power flow calculation on the induction motor according to the equivalent circuit model to obtain a power flow calculation result of a load node of the induction motor;

[0008] updating a current slip rate of the induction motor according to a power flow calculation result of a load node of the induction motor;

[0009] When the updated current slip rate satisfies a preset slip rate threshold, determining the active power consumed by the load node of the induction motor according to the updated current slip rate;

[0010] A load frequency response model of the induction motor is constructed according to the active power consumed by the load node of the induction motor and the system frequency.

[0011] Optionally, the power flow calculation result includes a voltage amplitude and a phase angle of a load node of the induction motor; and the step of updating the current slip rate of the induction motor according to the power flow calculation result of the load node of the induction motor includes:

[0012] determining a voltage vector value at a load node of the induction motor according to a voltage amplitude and a phase angle at the load node of the induction motor;

[0013] determining electromagnetic power based on a voltage vector value at a load node of the induction motor and a current vector value of a stator resistance and reactance of the induction motor;

[0014] determining mechanical power according to the rated mechanical power and current slip of the induction motor;

[0015] determining a rate of change of the slip of the induction motor according to the electromagnetic power, the mechanical power, and the inertia time constant of the induction motor based on a rotor motion equation of the induction motor;

[0016] The current slip of the induction motor at the next moment is updated according to the change rate of the slip of the induction motor.

[0017] Optionally, when the updated current slip rate satisfies a preset slip rate threshold, the step of determining the active power consumed by the load node of the induction motor according to the updated current slip rate includes:

[0018] Determining whether the updated current slip rate is less than the preset slip rate threshold;

[0019] When it is determined that the updated current slip is less than the preset slip threshold, the active power consumed by the load node of the induction motor is determined according to the updated current slip, the current vector value of the induction motor rotor, and the rotor resistance rating of the induction motor.

[0020] Optionally, the step of constructing a load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency includes:

[0021] determining a system frequency change rate according to the active power consumed by the load node of the induction motor at the current simulation moment and the active power consumed at the previous simulation moment, and the inertia time constant of the induction motor;

[0022] Update the current system frequency according to the system frequency change rate, and determine whether the current simulation time is less than the preset simulation time;

[0023] When it is determined that the current simulation time is less than the preset simulation time, the current simulation time is updated according to the preset time step, and the process proceeds to the step of performing power flow calculation on the induction motor according to the equivalent circuit model to obtain a power flow calculation result of a load node of the induction motor, until the current simulation time reaches the preset simulation time, the iteration is stopped, and the time variation relationship between the system frequency and the active power is output;

[0024] A load frequency response model of the induction motor is constructed according to the time variation relationship between the system frequency and the active power.

[0025] In a second aspect, the present invention further provides a system for modeling an induction motor load frequency response model, comprising:

[0026] The circuit equivalent module is used to perform circuit equivalence on the structure of the induction motor to obtain an equivalent circuit model;

[0027] a power flow calculation module, configured to perform power flow calculation on the induction motor according to the equivalent circuit model, and obtain a power flow calculation result of a load node of the induction motor;

[0028] a slip rate updating module, configured to update a current slip rate of the induction motor according to a power flow calculation result of a load node of the induction motor;

[0029] a power calculation module, configured to determine the active power consumed by the load node of the induction motor according to the updated current slip rate when the updated current slip rate satisfies a preset slip rate threshold;

[0030] The model building module is used to build a load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency.

[0031] Optionally, the power flow calculation result includes the voltage amplitude and phase angle of the load node of the induction motor; and the slip rate updating module includes:

[0032] a voltage determination module, configured to determine a voltage vector value of a load node of the induction motor according to a voltage amplitude and a phase angle of the load node of the induction motor;

[0033] an electromagnetic power determination module, configured to determine electromagnetic power based on a voltage vector value of a load node of the induction motor and a current vector value of a stator resistance and reactance of the induction motor;

[0034] a mechanical power determination module, configured to determine the mechanical power according to the rated mechanical power and the current slip rate of the induction motor;

[0035] a slip change determining module, configured to determine a rate of change of the slip of the induction motor based on a rotor motion equation of the induction motor, the electromagnetic power, the mechanical power, and an inertia time constant of the induction motor;

[0036] The slip updating module is configured to update the current slip of the induction motor at a next moment according to the rate of change of the slip of the induction motor.

[0037] Optionally, the power calculation module includes:

[0038] a judging module, configured to judge whether the updated current slip rate is less than the preset slip rate threshold;

[0039] an active power determination module configured to, when determining that the updated current slip is less than the preset slip threshold, determine the active power consumed by the load node of the induction motor based on the updated current slip, the current vector value of the induction motor rotor, and the rotor resistance rating of the induction motor.

[0040] Optionally, the model building module includes:

[0041] a frequency change determination module, configured to determine a system frequency change rate based on the active power consumed by the load node of the induction motor at the current simulation moment and the active power consumed at the previous simulation moment, and the inertia time constant of the induction motor;

[0042] Update the current system frequency according to the system frequency change rate, and determine whether the current simulation time is less than the preset simulation time;

[0043] a time variation module, configured to, when determining that the current simulation time is less than the preset simulation duration, update the current simulation time according to the preset time step, and execute the power flow calculation for the induction motor according to the equivalent circuit model to obtain the power flow calculation result of the load node of the induction motor, until the current simulation time reaches the preset simulation duration, stop iteration, and output the time variation relationship between the system frequency and the active power;

[0044] The response model determination module is used to construct a load frequency response model of the induction motor according to the time variation relationship between the system frequency and the active power.

[0045] In a third aspect, the present invention further provides an electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the induction motor load frequency response modeling method as described in the first aspect.

[0046] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the method for modeling the induction motor load frequency response model as described in the first aspect.

[0047] It can be seen from the above technical solutions that the present invention performs circuit equivalence on the structure of the induction motor, performs power flow calculation on the induction motor, and uses the power flow calculation result of the load node of the induction motor to update the current slip of the induction motor, so that the current slip of the induction motor meets the slip threshold, so as to reduce the error of the frequency simulation analysis of the large power grid, and determines the active power consumed by the load node of the induction motor through the updated current slip, thereby constructing a load frequency response model of the active power consumed by the load node of the induction motor and the system frequency, thereby improving the accuracy of the load frequency response of the induction motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 An application environment diagram of a method for modeling a load frequency response model of an induction motor provided by an embodiment of the present invention;

[0049] Figure 2 A flow chart of a method for modeling a load frequency response model of an induction motor provided by an embodiment of the present invention;

[0050] Figure 3 An equivalent circuit model of an induction motor provided by an embodiment of the present invention;

[0051] Figure 4 A schematic structural diagram of a system for modeling a load frequency response model of an induction motor provided by an embodiment of the present invention;

[0052] Figure 5 A schematic structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0053] In order for those skilled in the art to better understand the technical scheme of the present application, the technical scheme in the embodiments of the present application will be described clearly and completely below 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, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0054] The induction motor load frequency response modeling method provided by the embodiments of the present application can be applied to the application environment as shown in Figure 1 . In the application environment, each device node of the power grid system communicates with the server 102 through a network. The data storage system can store the data required to be processed by the server 102. The data storage system can be integrated on the server 102, or placed on a cloud or other network server. The server 102 can be a stand-alone physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server providing cloud computing services.

[0055] As shown in Figure 2 , the embodiments of the present application provide an induction motor load frequency response modeling method. Taking the server 102 in Figure 1 as an example, the method includes the following steps S1 to S5. Wherein:

[0056] Step S1, the structure of the induction motor is circuit equivalent, and an equivalent circuit model is obtained.

[0057] Wherein, the induction motor can be simplified into a load model with constant power factor or constant impedance, current or power. As shown in the equivalent circuit model of the induction motor, Figure 3 In the figure, U and φ are the voltage amplitude and phase angle of the induction motor terminal node; R s and X s are the stator resistance and reactance of the induction motor; I s is the current flowing through the stator resistance and reactance of the induction motor, which is a phasor; X m is the excitation reactance of the induction motor; R r and X r are the rated rotor resistance and rotor reactance of the induction motor; s is the slip of the induction motor; R=R r / s is the corrected rotor resistance of the motor considering the slip; I m is the current flowing through the excitation reactance of the induction motor, which is a phasor; I r is the current flowing through the rotor resistance of the induction motor, which is a phasor.

[0058] Step S2: performing power flow calculation on the induction motor according to the equivalent circuit model to obtain power flow calculation results of the load nodes of the induction motor.

[0059] The power flow calculation results include the voltage amplitude and phase angle of the load node of the induction motor.

[0060] Step S3: updating the current slip rate of the induction motor according to the power flow calculation result of the load node of the induction motor.

[0061] The slip of an induction motor is a key parameter that describes its operating state. It is defined as the difference between the synchronous speed and the actual speed divided by the synchronous speed. When analyzing the frequency response, it is important to ensure that the slip of the induction motor is extremely small to ensure a relatively accurate frequency response.

[0062] Specifically, the process of updating the current slip rate of the induction motor according to the power flow calculation result of the load node of the induction motor in step S3 includes:

[0063] Step S301: Determine a voltage vector value at a load node of the induction motor according to a voltage amplitude and a phase angle at the load node of the induction motor.

[0064] In polar coordinates, the voltage vector is directly described by its amplitude and phase angle.

[0065] Step S302 : determining electromagnetic power according to the voltage vector value of the load node of the induction motor and the current vector value of the stator resistance and reactance of the induction motor.

[0066] The calculation method of electromagnetic power is:

[0067]

[0068] Where, is the electromagnetic power, is the voltage vector value of the load node of the induction motor, is the current vector value of the stator resistance and reactance of the induction motor. for:

[0069]

[0070] Where j is the imaginary unit.

[0071] Step S303: Determine the mechanical power according to the rated mechanical power and the current slip rate of the induction motor.

[0072] The calculation method of mechanical power is:

[0073]

[0074] Where, is the mechanical power, is the rated mechanical power of the induction motor, and A, B, and C are all constants of the torque equation.

[0075] Step S304 : determining the rate of change of the slip of the induction motor based on the rotor motion equation of the induction motor and according to the electromagnetic power, the mechanical power and the inertia time constant of the induction motor.

[0076] Among them, the rotor motion equation of the induction motor is:

[0077] Where wr is the speed of the induction motor, H is the inertia time constant of the induction motor, and , by Substitute the rotor motion equation of the induction motor into the equation to obtain the rate of change of the induction motor's slip.

[0078] Step S305: updating the current slip of the induction motor at the next moment according to the change rate of the slip of the induction motor.

[0079] Among them, the current slip rate of the induction motor at the next moment is:

[0080] S(t+1)=s(t)+ ×dt

[0081] Where s(t) and S(t+1) are the slip rates of the induction motor at time t and t+1 respectively.

[0082] Step S4: When the updated current slip satisfies a preset slip threshold, determining the active power consumed by the load node of the induction motor according to the updated current slip.

[0083] It is necessary to ensure that the current slip rate meets a preset slip rate threshold, that is, the current slip rate should be small enough. Specifically, step S4 includes:

[0084] Step S401: Determine whether the updated current slip rate is less than a preset slip rate threshold.

[0085] Step S402: When it is determined that the updated current slip is less than the preset slip threshold, the active power consumed by the load node of the induction motor is determined according to the updated current slip, the current vector value of the induction motor rotor, and the rotor resistance rating of the induction motor.

[0086] The calculation method for the active power consumed by the load node of the induction motor is:

[0087]

[0088] Where, is the active power consumed by the load node of the induction motor, is the current vector value of the induction motor rotor. for:

[0089]

[0090] Among them, when it is judged that the updated current slip rate is not less than the preset slip rate threshold, it is necessary to proceed to the step of updating the current slip rate of the induction motor according to the flow calculation result of the load node of the induction motor until it is judged that the updated current slip rate is less than the preset slip rate threshold, wherein the slip rate threshold can be set to 0.0001pu.

[0091] Step S5: constructing a load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency.

[0092] Among them, the load frequency response model of the induction motor is based on the active external characteristics of the induction motor load when the system frequency changes. It establishes a mathematical function of the system frequency and the active power emitted or absorbed by the equipment. The input variable of the mathematical function is the system frequency f, and the output variable is the active power P output or absorbed by the equipment.

[0093]

[0094] The purpose of establishing an induction motor frequency response model is to calculate the system's global active power imbalance. Using the system's equivalent moment of inertia, the system frequency trend can be quickly determined, thereby providing relevant data on whether the system faces frequency safety and stability risks. Since the slip rate, s, is a time-varying variable and is related to variables such as system frequency and electromagnetic power, and the system's reactive power support is sufficient or the active power disturbance is minimal, the voltage amplitude at the induction motor's load node should remain unchanged before and after the disturbance to avoid affecting the frequency response.

[0095] Specifically, the process of constructing the load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency in step S5 includes:

[0096] Step S501 : determining a system frequency change rate according to the active power consumed by the load node of the induction motor at the current simulation moment, the active power consumed at the previous simulation moment, and the inertia time constant of the induction motor.

[0097] Among them, the system frequency change rate is:

[0098]

[0099] Where, is the system frequency, is the system frequency change rate, is the active power consumed at the previous simulation moment.

[0100] Step S502: update the current system frequency according to the system frequency change rate, and determine whether the current simulation time is less than the preset simulation time;

[0101] Step S503: When it is determined that the current simulation time is less than the preset simulation duration, the current simulation time is updated according to the preset time step, and the process goes to step S2 until the current simulation time reaches the preset simulation duration, the iteration stops, and the time variation relationship between the system frequency and the active power is output.

[0102] Step S504: construct a load frequency response model of the induction motor according to the time variation relationship between the system frequency and the active power.

[0103] It can be understood that the time-varying relationship between system frequency and active power represents the time-varying relationship between system frequency and active power. By fitting data based on the time-varying relationship between system frequency and active power, the functional relationship between system frequency and active power with respect to time can be obtained, which is the load frequency response model of the induction motor.

[0104] It should be noted that, in the embodiment of the present application, the structure of the induction motor is made circuit equivalent, and the power flow calculation is performed on the induction motor. The current slip rate of the induction motor is updated using the power flow calculation result of the load node of the induction motor, so that the current slip rate of the induction motor meets the slip rate threshold value, so as to reduce the error of the frequency simulation analysis of the large power grid, and the active power consumed by the load node of the induction motor is determined by the updated current slip rate, thereby constructing a load frequency response model of the active power consumed by the load node of the induction motor and the system frequency, thereby improving the accuracy of the load frequency response of the induction motor.

[0105] Based on the same inventive concept, an embodiment of the present application further provides an induction motor load frequency response modeling system for implementing the above-mentioned induction motor load frequency response modeling method.

[0106] The implementation solution provided by the system to solve the problem is similar to the implementation solution described in the above method. Therefore, the specific limitations in one or more embodiments of the induction motor load frequency response model modeling system provided below can be found in the above limitations on the induction motor load frequency response model modeling method, and will not be repeated here.

[0107] like Figure 4 As shown, the embodiment of the present application further provides a system for modeling a load frequency response model of an induction motor, comprising:

[0108] The circuit equivalent module 100 is used to perform circuit equivalence on the structure of the induction motor to obtain an equivalent circuit model;

[0109] The power flow calculation module 200 is used to perform power flow calculation on the induction motor according to the equivalent circuit model to obtain the power flow calculation result of the load node of the induction motor;

[0110] The slip rate updating module 300 is used to update the current slip rate of the induction motor according to the power flow calculation result of the load node of the induction motor;

[0111] a power calculation module 400 for determining the active power consumed by the load node of the induction motor according to the updated current slip rate when the updated current slip rate satisfies a preset slip rate threshold;

[0112] The model building module 500 is used to build a load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency.

[0113] In some embodiments, the power flow calculation result includes the voltage amplitude and phase angle of the load node of the induction motor; and the slip rate updating module includes:

[0114] a voltage determination module, configured to determine a voltage vector value of a load node of the induction motor according to a voltage amplitude and a phase angle of the load node of the induction motor;

[0115] an electromagnetic power determination module, configured to determine the electromagnetic power based on a voltage vector value of a load node of the induction motor and a current vector value of a stator resistance and reactance of the induction motor;

[0116] a mechanical power determination module, configured to determine the mechanical power according to the rated mechanical power and the current slip rate of the induction motor;

[0117] a slip change determination module for determining a slip change rate of the induction motor based on a rotor motion equation of the induction motor, electromagnetic power, mechanical power, and an inertia time constant of the induction motor;

[0118] The slip updating module is used to update the current slip of the induction motor at the next moment according to the change rate of the slip of the induction motor.

[0119] In some embodiments, the power calculation module includes:

[0120] A judgment module, used to judge whether the updated current slip rate is less than a preset slip rate threshold;

[0121] The active power determination module is configured to determine the active power consumed by the load node of the induction motor based on the updated current slip, the current vector value of the induction motor rotor, and the rotor resistance rating of the induction motor when it is determined that the updated current slip is less than a preset slip threshold.

[0122] In some embodiments, the model building module includes:

[0123] A frequency change determination module is used to determine the system frequency change rate according to the active power consumed by the load node of the induction motor at the current simulation moment and the active power consumed at the previous simulation moment, and the inertia time constant of the induction motor;

[0124] Update the current system frequency according to the system frequency change rate, and determine whether the current simulation time is less than the preset simulation time;

[0125] A time variation module is configured to update the current simulation time according to the preset time step when it is determined that the current simulation time is less than the preset simulation time, and to perform power flow calculation on the induction motor according to the equivalent circuit model to obtain the power flow calculation result of the load node of the induction motor, until the current simulation time reaches the preset simulation time, at which point the iteration stops and the time variation relationship between the system frequency and the active power is output;

[0126] The response model determination module is used to construct a load frequency response model of the induction motor according to the time variation relationship between the system frequency and the active power.

[0127] like Figure 5 As shown, an embodiment of the present application further provides an electronic device, the electronic device 10 includes a memory 20 and a processor 30, the memory 20 stores a computer program, and when the computer program is executed by the processor 30, the processor 30 executes the steps of the induction motor load frequency response model modeling method in any of the above embodiments.

[0128] An embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the steps of the method for modeling the induction motor load frequency response model as in any of the above embodiments are implemented.

[0129] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described systems, electronic devices, and computer storage media can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0130] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or apparatuses.

[0131] In several embodiments provided by the present invention, it is understood that each box in the flow chart or block diagram can represent a module, program segment or part of the code, and the module, program segment or part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order than that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved.

[0132] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, electronic devices, computer storage media and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0133] 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 these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0134] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0135] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for executing all or part of the steps of the method described in each embodiment of the present invention via a computer device (which can be a personal computer, server, or network device, etc.). The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0136] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for modeling an induction motor load frequency response model, characterized in that: include: The structure of the induction motor is subjected to circuit equivalence to obtain an equivalent circuit model; Performing power flow calculation on the induction motor according to the equivalent circuit model to obtain a power flow calculation result of a load node of the induction motor; the power flow calculation result includes a voltage amplitude and a phase angle of the load node of the induction motor; Updating the current slip rate of the induction motor according to the power flow calculation result of the load node of the induction motor includes: determining a voltage vector value at a load node of the induction motor according to a voltage amplitude and a phase angle at the load node of the induction motor; determining electromagnetic power based on a voltage vector value at a load node of the induction motor and a current vector value of a stator resistance and reactance of the induction motor; determining mechanical power according to the rated mechanical power and current slip of the induction motor; determining a rate of change of the slip of the induction motor according to the electromagnetic power, the mechanical power, and the inertia time constant of the induction motor based on a rotor motion equation of the induction motor; updating the current slip of the induction motor at a next moment according to the rate of change of the slip of the induction motor; When the updated current slip rate satisfies a preset slip rate threshold, determining the active power consumed by the load node of the induction motor according to the updated current slip rate includes: Determining whether the updated current slip rate is less than the preset slip rate threshold; When it is determined that the updated current slip is less than the preset slip threshold, determining the active power consumed by the load node of the induction motor according to the updated current slip, the current vector value of the induction motor rotor, and the rotor resistance rating of the induction motor; A load frequency response model of the induction motor is constructed according to the active power consumed by the load node of the induction motor and the system frequency.

2. The method for modeling an induction motor load frequency response model according to claim 1, wherein: The step of constructing a load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency comprises: determining a system frequency change rate according to the active power consumed by the load node of the induction motor at the current simulation moment and the active power consumed at the previous simulation moment, and the inertia time constant of the induction motor; Update the current system frequency according to the system frequency change rate, and determine whether the current simulation time is less than the preset simulation time; When it is determined that the current simulation time is less than the preset simulation time, the current simulation time is updated according to the preset time step, and the process proceeds to the step of performing power flow calculation on the induction motor according to the equivalent circuit model to obtain a power flow calculation result of a load node of the induction motor, until the current simulation time reaches the preset simulation time, the iteration is stopped, and the time variation relationship between the system frequency and the active power is output; A load frequency response model of the induction motor is constructed according to the time variation relationship between the system frequency and the active power.

3. A modeling system for an induction motor load frequency response model, characterized in that: include: The circuit equivalent module is used to perform circuit equivalence on the structure of the induction motor to obtain an equivalent circuit model; a power flow calculation module, configured to perform power flow calculation on the induction motor according to the equivalent circuit model to obtain a power flow calculation result of a load node of the induction motor; the power flow calculation result includes a voltage amplitude and a phase angle of the load node of the induction motor; a slip rate updating module, configured to update a current slip rate of the induction motor according to a power flow calculation result of a load node of the induction motor; The slip rate updating module includes: a voltage determination module, configured to determine a voltage vector value of a load node of the induction motor according to a voltage amplitude and a phase angle of the load node of the induction motor; an electromagnetic power determination module, configured to determine electromagnetic power based on a voltage vector value of a load node of the induction motor and a current vector value of a stator resistance and reactance of the induction motor; a mechanical power determination module, configured to determine the mechanical power according to the rated mechanical power and the current slip rate of the induction motor; a slip change determining module, configured to determine a rate of change of the slip of the induction motor based on a rotor motion equation of the induction motor, the electromagnetic power, the mechanical power, and an inertia time constant of the induction motor; a slip updating module, configured to update a current slip of the induction motor at a next moment according to a rate of change of the slip of the induction motor; A power calculation module is configured to determine the active power consumed by the load node of the induction motor according to the updated current slip rate when the updated current slip rate satisfies a preset slip rate threshold value; the power calculation module includes: a judging module, configured to judge whether the updated current slip rate is less than the preset slip rate threshold; an active power determination module, configured to, when it is determined that the updated current slip is less than the preset slip threshold, determine the active power consumed by the load node of the induction motor based on the updated current slip, the current vector value of the induction motor rotor, and the rotor resistance rating of the induction motor; The model building module is used to build a load frequency response model of the induction motor according to the active power consumed by the load node of the induction motor and the system frequency.

4. The induction motor load frequency response modeling system according to claim 3, characterized in that: The model building module includes: a frequency change determination module, configured to determine a system frequency change rate based on the active power consumed by the load node of the induction motor at the current simulation moment and the active power consumed at the previous simulation moment, and the inertia time constant of the induction motor; Update the current system frequency according to the system frequency change rate, and determine whether the current simulation time is less than the preset simulation time; a time variation module, configured to, when determining that the current simulation time is less than the preset simulation duration, update the current simulation time according to the preset time step, and execute the power flow calculation for the induction motor according to the equivalent circuit model to obtain the power flow calculation result of the load node of the induction motor, until the current simulation time reaches the preset simulation duration, stop iteration, and output the time variation relationship between the system frequency and the active power; The response model determination module is used to construct a load frequency response model of the induction motor according to the time variation relationship between the system frequency and the active power.

5. An electronic device, characterized in that: The electronic device includes a memory and a processor, wherein a computer program is stored in the memory. When the computer program is executed by the processor, the processor executes the steps of the induction motor load frequency response modeling method according to claim 1 or 2.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the steps of the method for modeling the induction motor load frequency response model according to claim 1 or 2 are implemented.

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