Electromagnetic transient modeling method of induction motor, electronic equipment and storage medium

Abstract

The embodiment of the invention relates to the technical field of electromagnetic transient simulation, and discloses an electromagnetic transient modeling method of an induction motor, electronic equipment and a storage medium. The electromagnetic transient modeling method of the induction motor comprises the following steps: determining a target admittance corresponding to a set rotating speed according to a discretization induction motor model; acquiring real-time admittance for simulation based on the discretized induction motor model; determining an equivalent injection current according to the target admittance, the real-time admittance and the discretized induction motor model; performing electromagnetic transient calculation according to the equivalent injection current, the target admittance and the discretized induction motor model to obtain electromagnetic parameters of the discretized induction motor model; and adjusting simulation of the discretized induction motor model according to the electromagnetic parameters, and returning to execute the step of acquiring the real-time admittance of simulation based on the discretized induction motor model until a simulation stop condition is reached. The efficiency and the accuracy of electronic transient modeling of the induction motor are at least improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of electromagnetic transient simulation, and in particular to an electromagnetic transient modeling method, electronic device, and storage medium for an induction motor. Background Art

[0002] As a very popular type of induction motor, the rotor wound induction motor is used in many applications such as doubly-fed wind power generation and pumped storage. In particular, doubly-fed wind power generation has the advantages of low cost and high wind energy conversion efficiency. It is currently one of the most important forms of wind power generation. With the vigorous development of new energy, the proportion of new energy equipment such as wind, solar and storage in the power system is increasing, and the application of rotor wound induction motors is also receiving more and more attention.

[0003] However, the efficiency and accuracy of current electromagnetic transient modeling schemes for induction motors need to be improved. Summary of the invention

[0004] The embodiments of the present application provide an electromagnetic transient modeling method, electronic device, and storage medium for an induction motor, which are at least beneficial to improving the efficiency and accuracy of electronic transient modeling of the induction motor.

[0005] According to some embodiments of the present application, a first aspect of the embodiments of the present application provides an electromagnetic transient modeling method for an induction motor, comprising: determining a target admittance corresponding to a set speed according to a discretized induction motor model; obtaining a real-time admittance for simulation based on the discretized induction motor model; determining an equivalent injection current according to the target admittance, the real-time admittance and the discretized induction motor model; performing electromagnetic transient calculations according to the equivalent injection current, the target admittance and the discretized induction motor model to obtain electromagnetic parameters of the discretized induction motor model; adjusting the simulation of the discretized induction motor model according to the electromagnetic parameters, and returning to execute the step of obtaining the real-time admittance for simulation based on the discretized induction motor model until a simulation stop condition is reached.

[0006] In some embodiments, determining the equivalent injection current based on the target admittance, the real-time admittance and the discretized induction motor model includes: determining the admittance difference between the real-time admittance and the target admittance; and determining the equivalent injection current based on the admittance difference, the target admittance and the real-time discretized injection current simulated by the discretized induction motor model.

[0007] In some embodiments, the discretized induction motor model is: Among them, I abc (t) is the real-time stator and rotor injection current of the discretized induction motor model in the abc coordinate system, is the real-time admittance of the discretized induction motor model, V abc (t) is the real-time stator and rotor voltage of the discretized induction motor model in the abc coordinate system, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time length of ΔT from the current; the real-time discretized injection current simulated according to the admittance difference, the target admittance and the discretized induction motor model is used to determine the equivalent injection current, which is determined by the following expression: J′ abc (t-ΔT)=ΔGV abc (t-ΔT)+J abc (t-ΔT); where J′ abc (t-ΔT) is the equivalent injected current of the discretized induction motor model in the abc coordinate system, ΔG is the admittance difference, V abc (t-ΔT) is the stator and rotor voltage of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time.

[0008] In some embodiments, the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time length of ΔT from the current time is determined by the following expression: Among them, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time. V dq (t-ΔT) and I dq (t-ΔT) is the stator and rotor voltage and stator and rotor current of the discretized induction motor model in the dq coordinate system at a time ΔT from the current time; R s is the stator resistance parameter in the discretized induction motor model, R' r is the rotor resistance parameter (coupled to the stator side) in the discretized induction motor model, L ls is the stator leakage inductance in the discretized induction motor model, L′ rl is the rotor leakage inductance parameter (coupled to the stator side) in the discretized induction motor model, L m is the excitation inductance parameter in the discretized induction motor model, w is the set speed, and w r is the rotor speed parameter in the discretized induction motor model.

[0009] In some embodiments, the electromagnetic transient calculation is performed according to the equivalent injected current, the target admittance and the discretized induction motor model to obtain the electromagnetic parameters of the discretized induction motor model, which is implemented by the following expression: abc (t) = GV abc (t)+J′ abc (t-ΔT); where I abc (t) is the real-time electromagnetic parameter of the discretized induction motor model, G is the target admittance, V abc (t) is the real-time stator and rotor voltage of the discretized induction motor model in the abc coordinate system, J′ abc (t-ΔT) is the equivalent injected current of the discretized induction motor model in the abc coordinate system at a time ΔT away from the current value.

[0010] In some embodiments, adjusting the simulation of the discrete induction motor model according to the electromagnetic parameters includes: determining corresponding mechanical parameters according to the electromagnetic parameters, wherein the mechanical parameters include at least one of the following: rotational speed and torque; and updating the simulation parameters of the discrete induction motor model according to the mechanical information.

[0011] In some embodiments, the discretized induction motor model is a model in an abc coordinate system, and determining the target admittance corresponding to the set speed based on the constructed discretized electromagnetic transient simulation model and the set speed includes: determining, based on the discretized induction motor model and the set speed, a three-phase admittance matrix of the stator in the abc coordinate system and a three-phase admittance matrix of the rotor in the abc coordinate system that conform to the definition of the node admittance matrix, as the target admittance.

[0012] In some embodiments, before determining the target admittance corresponding to the set speed according to the discretized induction motor model, the method further includes: acquiring parameters of the induction motor, wherein the parameters of the induction motor include one or a combination of the following information: stator resistance, stator leakage inductance, rotor resistance, rotor leakage inductance, excitation inductance, pole pair number, rated frequency, the given speed, rotor speed, moment of inertia friction coefficient, initial speed, initial angle, initial three-phase current of the stator winding, and initial three-phase current of the rotor winding; converting the parameters of the induction motor from the abc coordinate system to the dq coordinate system to construct the induction motor model in the dq coordinate system; performing trapezoidal discretization processing on the induction motor model in the dq coordinate system to obtain a discretized initial induction motor model; converting the discretized initial induction motor model from the dq coordinate system to the abc coordinate system to obtain the discretized induction motor model.

[0013] According to some embodiments of the present application, a second aspect of the embodiments of the present application further provides an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the electromagnetic transient modeling method of an induction motor as described in any one of the first aspects.

[0014] According to some embodiments of the present application, a third aspect of the embodiments of the present application further provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the electromagnetic transient modeling method of an induction motor as described in any one of the first aspects.

[0015] The technical solution provided in the embodiment of the present application has at least the following advantages:

[0016] After determining the discretized induction motor model, the target admittance corresponding to the set speed is determined, so that the target admittance is used as a reference, and the real-time admittance simulated based on the discretized induction motor model and the discretized induction motor model are used to determine the equivalent injection current, and further electromagnetic transient calculation is performed to achieve simulation adjustment of the discretized induction motor model, so as to continuously approach the transient through iteration of the above process, so that the electromagnetic transient modeling is more accurate. In particular, when making adjustments, the electromagnetic parameters used for adjustment are further determined by the real-time admittance, which are more compatible with the current discrete induction motor model simulation state, and are no longer limited by the set adjustment step size, so that more accurate and rapid adjustments are achieved, which improves the efficiency and accuracy of electromagnetic transient modeling of induction motors as a whole. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0018] Figure 1 The process of the electromagnetic transient modeling method of the induction motor provided in the embodiment of the present application is Figure 1 ;

[0019] Figure 2 The process of the electromagnetic transient modeling method of the induction motor provided in the embodiment of the present application is Figure 2 ;

[0020] Figure 3 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0021] As can be seen from the background technology, the efficiency and accuracy of the current electromagnetic transient modeling scheme for induction motors need to be improved urgently.

[0022] After analysis, it is found that the current electromagnetic transient modeling scheme of induction motors is not efficient and accurate because at least: the current transient modeling scheme of induction motors usually adopts variable admittance form, or adopts forward (or backward) Euler method and other solution methods, resulting in low calculation efficiency or simulation accuracy. In particular, in practical applications, such as induction click application scenarios in large-scale power systems, the number of nodes in the simulation is large, and the inversion operation of the impedance matrix consumes a lot of computing resources, resulting in low simulation efficiency and dragging down the simulation speed; the simulation accuracy of the forward and backward Euler methods is low. In order to improve the simulation accuracy, the simulation step size needs to be reduced, which equivalently reduces the simulation efficiency. In addition, in the iterative process of modeling, the iterative method of the existing scheme also affects the accuracy and efficiency of modeling. For example, when iterating according to the preset step size, the accuracy is the preset step size. When the step size is set to a small value to achieve the desired accuracy, the number of iterations will be too many, and vice versa, the accuracy will not be satisfactory.

[0023] To this end, the embodiment of the present application provides an electromagnetic transient modeling method, electronic device and storage medium for an induction motor, which provides a new iterative idea. On the one hand, by providing the target admittance as a reference and iterative guide, the iteration is made more accurate and efficient. On the other hand, the simulation real-time state of the induction motor model is combined, so that each iteration can be adapted to the real-time state of the induction motor model, and will not be over-adjusted or under-adjusted, thereby supporting more accurate and efficient iterative adjustment, accurately approximating the desired electromagnetic transient modeling, and realizing more efficient and accurate transient modeling of induction motors. This is to further improve the efficiency and accuracy of electromagnetic transient simulation of induction motor systems such as large-scale new power systems with a large proportion of new energy.

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present application, many technical details are provided in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can be implemented.

[0025] The division of the following embodiments is for the convenience of description and shall not constitute any limitation on the specific implementation of the present application. The embodiments may be combined with each other and referenced to each other without contradiction.

[0026] On the one hand, the embodiment of the present application provides an electromagnetic transient modeling method for an induction motor, which is applicable to any electronic device with computing and simulation functions, such as a computer, a server, etc., which will not be listed here one by one. The electromagnetic transient modeling method for an induction motor provided by the embodiment of the present application can improve the efficiency and accuracy of the electromagnetic transient modeling of the induction motor. To facilitate the understanding of the electromagnetic transient modeling method provided by the embodiment of the present application, the following will be combined with Figure 1 and Figure 2 The method flow is described in detail below.

[0027] In some embodiments, Figure 1 As shown, the electromagnetic transient modeling method of the induction motor may include the following steps:

[0028] Step 101: Determine a target admittance corresponding to a set rotation speed according to a discretized induction motor model.

[0029] Step 102: obtaining a real-time admittance simulated based on a discretized induction motor model.

[0030] Step 103: determining an equivalent injection current according to the target admittance, the real-time admittance and the discretized induction motor model.

[0031] Step 104 , performing electromagnetic transient calculation according to the equivalent injected current, the target admittance and the discretized induction motor model to obtain electromagnetic parameters of the discretized induction motor model.

[0032] Step 105 , adjusting the simulation of the discretized induction motor model according to the electromagnetic parameters, and returning to the step of obtaining the real-time admittance simulated based on the discretized induction motor model until the simulation stop condition is reached.

[0033] In this way, after determining the discretized induction motor model, the target admittance corresponding to the set speed is determined, so that the target admittance is used as a reference, and the real-time admittance and the discretized induction motor model simulated based on the discretized induction motor model are used to determine the equivalent injection current, and further perform electromagnetic transient calculations to achieve simulation adjustment of the discretized induction motor model, so as to continuously approach the transient through iterations of the above process, making the electromagnetic transient modeling more accurate. In particular, when making adjustments, the electromagnetic parameters used for adjustment are further determined by the real-time admittance, which are more compatible with the current discrete induction motor model simulation state, and are no longer limited to the set adjustment step size, thereby achieving more accurate and rapid adjustments, and improving the efficiency and accuracy of electromagnetic transient modeling of induction motors as a whole.

[0034] To facilitate better understanding of those skilled in the art Figure 1 The embodiment shown, the steps of which will be explained below.

[0035] In step 101, the target admittance corresponding to the set speed is determined according to the discretized induction motor model. Among them, the embodiment of the present application does not limit the discretized induction motor model, which can be any physical model (or circuit model, etc.) obtained by abstracting the actual induction motor and modeling and discretizing it. It can be understood that there are many types of induction motors, and the way of abstracting the corresponding physical model from the induction motor according to different needs is also different. At the same time, the discretization method can also be different, so the obtained discretized induction motor model is also different. It should be noted that the physical model obtained by abstracting the actual induction motor, the modeling based on the physical model of the induction motor, and the discretization are all recorded in the relevant prior art, and they will not be listed and repeated here. The following is for ease of understanding, mainly outside the relevant technology to provide a method for generating a discretized induction motor model, but this does not mean that the electromagnetic transient modeling method of the induction motor provided in the embodiment of the present application must obtain a discretized induction motor model as shown in the following example.

[0036] In some embodiments, according to the discretized induction motor model, before determining the target admittance corresponding to the set speed, the electromagnetic transient modeling method of the induction motor also constructs a discretized induction motor model. Specifically, the parameters of the induction motor are first obtained, wherein, according to different induction motors, different modeling requirements, etc., information as parameters of the induction motor can be obtained, which may include one or a combination of the following information: stator resistance, stator leakage inductance, rotor resistance, rotor leakage inductance, excitation inductance, pole pair number, rated frequency, given speed, rotor speed, moment of inertia friction coefficient, initial speed, initial angle, initial three-phase current of stator winding, initial three-phase current of rotor winding. Secondly, the parameters of the induction motor are converted from the abc coordinate system to the dq coordinate system to construct the induction motor model in the dq coordinate system. Then, the induction motor model in the dq coordinate system is discretized by the trapezoidal method to obtain a discretized induction motor model. Finally, the discretized induction motor model is converted from the dq coordinate system to the abc coordinate system to obtain a discretized induction motor model in the abc coordinate system. At the same time, the above parameters can be expressed as actual values ​​or per-unit values ​​when they are obtained, which will not be repeated here.

[0037] In this way, by acquiring data in the abc coordinate system where relevant parameters are easier to obtain, the difficulty of data acquisition is reduced, and further combined with the coordinate system conversion, the parameters can be converted to the dq coordinate system which is easier to construct relevant expressions to form a model, thereby reducing the difficulty of model construction, and finally back-converted to the abc coordinate system for easier data processing, reducing the difficulty of subsequent processing iterations, thereby reducing the overall difficulty of implementing the electromagnetic transient modeling method for the induction motor and further improving the implementation efficiency of the electromagnetic transient modeling method for the induction motor.

[0038] Furthermore, the embodiments of the present application do not limit the set rotation speed. Different rotation speed values ​​can be set as the set rotation speed according to different modeling requirements, different application scenario requirements, etc., which will not be listed or elaborated here one by one.

[0039] In addition, under the determined discretized induction motor model, by giving a speed, an admittance (usually expressed in the form of a matrix) can be uniquely calculated. The calculation of the above admittance has been recorded in the related art, and it is not listed here one by one. For ease of understanding, a method for determining a target admittance is mainly provided here outside the related art, but this does not mean that the electromagnetic transient modeling method of the induction motor provided in the embodiment of the present application must obtain a determined target admittance as shown in the following example.

[0040] In some embodiments, the discretized induction motor model is a model in the abc coordinate system. Accordingly, according to the constructed discretized electromagnetic transient simulation model and the set speed, the target admittance corresponding to the set speed is determined. This can be achieved in the following way: according to the discretized induction motor model and the set speed, the three-phase admittance matrix of the stator in the abc coordinate system and the three-phase admittance matrix of the rotor in the abc coordinate system that conform to the definition of the node admittance matrix are determined as the target admittance.

[0041] In this way, the admittance is determined separately by the stator and rotor in the induction motor, so that the determination of the target admittance is simplified, with lower complexity and less calculation. At the same time, the target admittance matrix is ​​only calculated once during initialization, and the subsequent iterations will no longer repeat the calculation. Since the matrix inversion of each iteration is very time-consuming, the use of a fixed admittance matrix can greatly improve the computational efficiency of electromagnetic transient simulation.

[0042] In step 102, a real-time admittance simulated based on a discretized induction motor model is obtained. The embodiment of the present application does not limit the method for obtaining the simulated real-time admittance, which may be setting a real-time simulation output, in which the admittance is included, or setting the sampling content, and calculating the corresponding admittance based on the sampled parameters, etc., which will not be listed or described here one by one.

[0043] In step 103, the equivalent injection current is determined according to the target admittance, the real-time admittance and the discretized induction motor model. Among them, in the embodiment of the present application, the equivalent injection current is mainly used to characterize the gap between the discretized induction motor model under the current real-time admittance and the expected state of the discretized induction motor model under the target admittance, so as to guide the adjustment of the model in the subsequent process. In implementation, any method for determining the equivalent injection current that can support subsequent adjustments and iterations based on the above ideas can be combined with the implementation of step 103. For ease of understanding, relevant examples will be given below, but this does not mean that the method for determining the equivalent injection current in the embodiment of the present application can only be as shown in the following example.

[0044] In some embodiments, determining the equivalent injection current based on the target admittance, the real-time admittance and the discretized induction motor model can be achieved in the following manner: determining the admittance difference between the real-time admittance and the target admittance; determining the equivalent injection current based on the real-time discretized injection current simulated by the admittance difference, the target admittance and the discretized induction motor model.

[0045] In this way, the reference nature of the target admittance can be fully utilized, combined with the deviation of the real-time admittance relative to the target admittance, that is, the admittance difference, and the real-time discretized injection current simulated by the discretized induction motor model as the real-time state of the discretized induction motor model, to determine a more appropriate, more accurate and more effective equivalent injection current, so that the subsequent simulation adjustment based on the equivalent injection current will be more accurate and effective, and adapt to the real-time simulation state of the discretized induction motor model, avoiding the occurrence of over-adjustment, misadjustment and the like.

[0046] In some embodiments, the discretized induction motor model is: Among them, I abc (t) is the real-time stator and rotor injection current of the discretized induction motor model in the abc coordinate system, is the real-time admittance of the discretized induction motor model, V abc (t) is the real-time stator and rotor voltage of the discretized induction motor model in the abc coordinate system, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current. Accordingly, the equivalent injection current is determined based on the admittance difference, the target admittance and the real-time discretized injection current simulated by the discretized induction motor model, which can be determined by the following expression: J′ abc (t-ΔT)=ΔGV abc (t-ΔT)+J abc (t-ΔT); where J′ abc (t-ΔT) is the equivalent injected current of the discretized induction motor model in the abc coordinate system, ΔG is the admittance difference, V abc(t-ΔT) is the stator and rotor voltage of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time, J abc (t-ΔT) is the stator and rotor injected current of the discretized induction motor model in the abc coordinate system, ΔT time away from the current.

[0047] In this way, by determining the equivalent injected current in a simple manner, the efficiency of electromagnetic transient modeling of the induction motor can be further improved while ensuring accuracy.

[0048] In step 104, electromagnetic transient calculation is performed based on the equivalent injected current, the target admittance and the discretized induction motor model to obtain the electromagnetic parameters of the discretized induction motor model. It can be understood that, according to different requirements, electromagnetic transient calculation will be performed in combination with different contents. For example, in some embodiments, electromagnetic transient calculation is performed based on the equivalent injected current, the target admittance and the discretized induction motor model to obtain the electromagnetic parameters of the discretized induction motor model, which can be achieved by the following expression: abc (t) = GV abc (t)+J′ abc (t-ΔT); where I abc (t) is the real-time electromagnetic parameter of the discretized induction motor model, G is the target admittance, V abc (t) is the real-time stator and rotor voltage of the discretized induction motor model in the abc coordinate system, J′ abc (t-ΔT) is the equivalent injected current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current. In this way, the target admittance and the real-time state of the electromagnetic parameters of the discretized induction motor model V are further introduced. abc (t), further strengthening the reference to the current state of the discretized induction motor model and the target admittance during subsequent adjustments, so that the accuracy, effectiveness and efficiency of the adjustment iterations are further improved.

[0049] Of course, the above are only examples. In some embodiments, the equivalent injection current can be directly used as the electromagnetic parameter, or the current electromagnetic parameter can be determined by further combining the equivalent injection current determined last time (and / or the electromagnetic parameter determined last time), so that the current adjustment can be better guided by the last adjustment, and the accuracy of adjustment and iteration can be further improved. These will not be listed one by one here.

[0050] In step 105, the simulation of the discretized induction motor model is adjusted according to the electromagnetic parameters, and the step of obtaining the real-time admittance for simulation based on the discretized induction motor model is returned to be executed until the simulation stop condition is reached. Different adjustment methods can be set according to different needs. For example, in some embodiments, the simulation of the discretized induction motor model can be adjusted according to the electromagnetic parameters. The following methods can be implemented: according to the electromagnetic parameters, the corresponding mechanical parameters are determined, wherein the mechanical parameters include at least one of the following: speed and torque; according to the mechanical information, the simulation parameters of the discretized induction motor model are updated. In this way, more direct and intuitive parameters are obtained for simulation adjustment, so that the adjustment efficiency is more efficient, thereby further improving the efficiency of electromagnetic transient modeling of the induction motor.

[0051] Of course, the above are only examples. In some embodiments, a proportional parameter can be assigned to this adjustment based on the effect of the previous adjustment, so that the actual adjusted mechanical information can be determined based on the proportional parameter and the currently determined mechanical information. In this way, a more stable and smooth adjustment can be achieved, avoiding simulation mutations that affect the simulation effect.

[0052] It should be noted that the embodiments of the present application do not limit the simulation stop condition. For example, the simulation stop condition may be reaching a preset number of iterations. For another example, the simulation stop condition may also be that the change value of the current newly determined electromagnetic parameter relative to the last electromagnetic parameter is less than a preset value (which may be a set value, or the simulation accuracy of an electronic device that performs electromagnetic transient modeling of an induction motor, etc.). I will not go into details here.

[0053] In order to facilitate those skilled in the art to better understand the electromagnetic transient modeling method of the induction motor described in the above embodiment, the following will take the induction motor as a conventional rotor wound induction motor and combine Figure 2 The process shown is described by way of example.

[0054] Step 201, obtaining parameters of the rotor wound induction motor, including: stator resistance R s , stator leakage inductance L ls , rotor resistance (coupled to the stator side) R' r , rotor leakage inductance (coupled to the stator side) L' rl , magnetizing inductance L m , pole pair number P, rated frequency f n , given the electrical angular velocity w g , given rotor speed w rg , moment of inertia J, friction coefficient F; initial information includes: initial speed w0, initial angle θ g , initial three-phase current of stator and rotor windings I ABC and I abcAt the same time, it is assumed that the stator and rotor are both connected in a Y-connection manner, and the positive direction of the voltage and current of the stator and rotor is specified according to the motor convention.

[0055] Step 202, select the reference coordinate system as the dq coordinate system, convert the parameters of the induction motor from the abc coordinate system to the dq coordinate system, and construct the induction motor model in the dq coordinate system. Specifically, obtain the electrical angular velocity w and electrical angle θ of the dq axis reference coordinate system, and determine the Parker transformation from the abc coordinate system to the dq coordinate system of the stator and rotor as:

[0056]

[0057] Among them, θ r is the electrical angle of the rotor.

[0058] Thus, the Parker transformation of the stator and rotor can be synthesized into a matrix:

[0059]

[0060] Moreover, in the dq coordinate system, the voltage and current equations of the stator and rotor are:

[0061]

[0062] in, w r is the rotor speed. The other related parameters are described in step 1 and will not be repeated here.

[0063] Step 203, the induction motor model in the dq coordinate system is discretized by the trapezoidal method to obtain a discretized initial induction motor model. Specifically, the voltage and current equations of the stator and rotor are discretized by the trapezoidal method to obtain the following discretized initial induction motor model:

[0064]

[0065] Here, since the trapezoidal method is used, k=1.

[0066] In addition, when the discretized initial induction motor model is obtained, the simulation can be started based on the discretized initial induction motor model with the initial information as the initial state.

[0067] Step 204: convert the discretized initial induction motor model from the dq coordinate system to the abc coordinate system to obtain a discretized induction motor model. Specifically, the following Park inverse transformation from the dq coordinate system of the stator and rotor to the abc coordinate system is used:

[0068]

[0069] That is, the Parker inverse transform of the stator and rotor can also be synthesized into the following matrix:

[0070]

[0071] Furthermore, the discretized initial induction motor model is transformed from the dq coordinate system to the abc coordinate system, and the discretized induction motor model shown below is obtained:

[0072]

[0073] Among them, V abc (t) and I abc (t) are the three-phase voltage and current matrices of the stator and rotor, That is, real-time admittance; That is, the stator and rotor injection current of ΔT time from the current;

[0074] Step 205, according to the discretized induction motor model and the set speed, determine the three-phase admittance matrix of the stator in the abc coordinate system and the three-phase admittance matrix of the rotor in the abc coordinate system that meet the definition of the node admittance matrix as the target admittance. Specifically, w=w g 、w r =w rg Substituting into the above expression: The calculation expressions of its related parameters will give the three-phase admittance matrix parameters G in the stator abc coordinate system of the admittance matrix. ssg And the three-phase admittance matrix G of the rotor in the abc coordinate system rrg , that is, the target admittance is obtained

[0075] Step 206, obtain the real-time admittance simulated based on the discretized induction motor model, specifically, the real-time dq-axis reference coordinate system electrical angular velocity w and the real-time rotor speed w of the motor r Substituting into the above expression: The calculation expressions of its related parameters can be used to obtain the real-time admittance and further determine the corresponding admittance difference:

[0076]

[0077] Step 207, determining the equivalent injection current according to the admittance difference, the target admittance and the real-time discretized injection current simulated by the discretized induction motor model. Specifically, the equivalent injection current is determined by the following expression:

[0078]

[0079] Step 208, according to the equivalent injected current, the target admittance and the discretized induction motor model, the electromagnetic parameters of the discretized induction motor model are obtained. Specifically, it is realized by the following expression:

[0080]

[0081] The above equivalent injection current and target admittance are transferred to the electromagnetic transient simulation algorithm for electromagnetic transient calculation, and the new voltage and current information of the circuit are obtained. In particular, since the target admittance remains unchanged, the target admittance only needs to be transferred once, and subsequent iterations do not need to be repeated.

[0082] Step 209: determining corresponding mechanical parameters according to the electromagnetic parameters, wherein the mechanical parameters include at least one of the following: rotation speed and torque; and updating simulation parameters of the discretized induction motor model according to the mechanical information.

[0083] Step 210 , detect whether the simulation stop condition is met, if so, execute step 211 , if not, return to step 206 .

[0084] Step 211, end the current simulation.

[0085] The step division of the above methods is only for the purpose of clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent; adding insignificant modifications to the algorithm or process or introducing insignificant designs without changing the core design of the algorithm and process are all within the scope of protection of this patent.

[0086] Another aspect of the present application embodiment further provides an electronic device, such as Figure 3 As shown, it includes: at least one processor 301; and a memory 302 that is communicatively connected to the at least one processor 301; wherein the memory 302 stores instructions that can be executed by the at least one processor 301, and the instructions are executed by the at least one processor 301 so that the at least one processor 301 can execute the electromagnetic transient modeling method of the induction motor described in any of the above method embodiments.

[0087] The memory 302 and the processor 301 are connected in a bus manner, and the bus may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors 301 and the memory 302 together. The bus can also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on a transmission medium. The data processed by the processor 301 is transmitted on a wireless medium via an antenna, and further, the antenna also receives data and transmits the data to the processor 301.

[0088] The processor 301 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management and other control functions. The memory 302 can be used to store data used by the processor 301 when performing operations.

[0089] Another aspect of the present application embodiment further provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the above method embodiment is implemented.

[0090] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including a number of instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0091] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present application, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. A method for electromagnetic transient modeling of an induction motor, characterized in that: include: According to the discretized induction motor model, the target admittance corresponding to the set speed is determined; Acquiring a real-time admittance simulated based on the discretized induction motor model; Determining an equivalent injection current according to the target admittance, the real-time admittance and the discretized induction motor model; Performing electromagnetic transient calculation according to the equivalent injected current, the target admittance and the discretized induction motor model to obtain electromagnetic parameters of the discretized induction motor model; The simulation of the discretized induction motor model is adjusted according to the electromagnetic parameters, and the step of obtaining the real-time admittance simulated based on the discretized induction motor model is returned to be executed until a simulation stop condition is reached.

2. The electromagnetic transient modeling method of an induction motor according to claim 1, characterized in that: The determining of the equivalent injected current according to the target admittance, the real-time admittance and the discretized induction motor model comprises: determining an admittance difference between the real-time admittance and the target admittance; The equivalent injection current is determined according to the admittance difference, the target admittance and the real-time discretized injection current simulated by the discretized induction motor model.

3. The electromagnetic transient modeling method of an induction motor according to claim 2, characterized in that: The discretized induction motor model is: Among them, I abc (t) is the real-time stator and rotor injection current of the discretized induction motor model in the abc coordinate system, is the real-time admittance of the discretized induction motor model, V abc (t) is the real-time stator and rotor voltage of the discretized induction motor model in the abc coordinate system, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time; The equivalent injection current is determined according to the real-time discretized injection current simulated according to the admittance difference, the target admittance and the discretized induction motor model, and is determined by the following expression: J′ abc (t-ΔT)=ΔGV abc (t-ΔT)+J abc (t-ΔT); Among them, J′ abc (t-ΔT) is the equivalent injected current of the discretized induction motor model in the abc coordinate system, ΔG is the admittance difference, V abc (t-ΔT) is the stator and rotor voltage of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time.

4. The electromagnetic transient modeling method of an induction motor according to claim 3, characterized in that: The stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time length of ΔT from the current is determined by the following expression: Among them, J abc (t-ΔT) is the stator and rotor injection current of the discretized induction motor model in the abc coordinate system at a time ΔT from the current time. V dq (t-ΔT) and I dq (t-ΔT) is the stator and rotor voltage and stator and rotor current of the discretized induction motor model in the dq coordinate system at a time ΔT from the current time; R s is the stator resistance parameter in the discretized induction motor model, R' r is the rotor resistance parameter (coupled to the stator side) in the discretized induction motor model, L ls is the stator leakage inductance in the discretized induction motor model, L′ rl is the rotor leakage inductance parameter (coupled to the stator side) in the discretized induction motor model, L m is the excitation inductance parameter in the discretized induction motor model, w is the set speed, and w r is the rotor speed parameter in the discretized induction motor model.

5. The electromagnetic transient modeling method of an induction motor according to any one of claims 1 to 4, characterized in that: The electromagnetic transient calculation is performed according to the equivalent injected current, the target admittance and the discretized induction motor model to obtain the electromagnetic parameters of the discretized induction motor model, which is achieved by the following expression: I abc (t)=GV abc (t)+J′ abc (t-ΔT); Among them, I abc (t) is the real-time electromagnetic parameter of the discretized induction motor model, G is the target admittance, V abc (t) is the real-time stator and rotor voltage of the discretized induction motor model in the abc coordinate system, J′ abc (t-ΔT) is the equivalent injected current of the discretized induction motor model in the abc coordinate system at a time ΔT away from the current value.

6. The electromagnetic transient modeling method of an induction motor according to any one of claims 1 to 4, characterized in that: The step of adjusting the simulation of the discretized induction motor model according to the electromagnetic parameters comprises: Determine corresponding mechanical parameters according to the electromagnetic parameters, wherein the mechanical parameters include at least one of the following: rotation speed and torque; Simulation parameters of the discretized induction motor model are updated according to the mechanical information.

7. The electromagnetic transient modeling method of an induction motor according to any one of claims 1 to 4, characterized in that: The discrete induction motor model is a model in the abc coordinate system, and the target admittance corresponding to the set speed is determined according to the constructed discrete electromagnetic transient simulation model and the set speed, including: According to the discretized induction motor model and the set speed, a three-phase admittance matrix in the stator abc coordinate system and a three-phase admittance matrix in the rotor abc coordinate system that meet the definition of the node admittance matrix are determined as the target admittance.

8. The electromagnetic transient modeling method of an induction motor according to any one of claims 1 to 4, characterized in that: Before determining the target admittance corresponding to the set speed according to the discretized induction motor model, the method further includes: Acquire parameters of the induction motor, wherein the parameters of the induction motor include one or a combination of the following information: stator resistance, stator leakage inductance, rotor resistance, rotor leakage inductance, excitation inductance, pole pair number, rated frequency, the given speed, rotor speed, moment of inertia friction coefficient, initial speed, initial angle, initial three-phase current of stator winding, and initial three-phase current of rotor winding; Converting the parameters of the induction motor from the abc coordinate system to the dq coordinate system to construct an induction motor model in the dq coordinate system; Performing a trapezoidal method discretization process on the induction motor model in the dq coordinate system to obtain a discretized initial induction motor model; The discretized initial induction motor model is converted from the dq coordinate system to the abc coordinate system to obtain the discretized induction motor model.

9. An electronic device, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can perform the electromagnetic transient modeling method for an induction motor according to any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the electromagnetic transient modeling method for an induction motor according to any one of claims 1 to 8 is implemented.

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