CN118759361A - AC excitation motor parameter test identification method, device and computer equipment - Google Patents

Abstract

The application relates to an alternating-current excitation motor parameter test identification method, an alternating-current excitation motor parameter test identification device and computer equipment, and relates to the technical field of motor parameter measurement. The method comprises the following steps: testing the motor to be tested in the first circuit environment according to the test signal to obtain position angle data of a rotor in the motor to be tested; testing the motor to be tested in the second circuit environment according to the test signal to obtain target induced current signals corresponding to each current detection point in the motor to be tested in the second circuit environment; performing magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal of the motor to be tested corresponding to any axis; and performing time domain analysis expression fitting on the transformed current signal according to a curve fitting method to obtain a fitted current time domain expression. The method can improve the parameter measurement effect of the alternating-current excitation motor.

Description

AC excitation motor parameter test identification method, device and computer equipment

Technical Field

The present application relates to the technical field of motor parameter determination, and in particular to an AC excitation motor parameter test identification method, device, computer equipment, computer-readable storage medium and computer program product.

Background Art

In the new power system, new energy sources are gradually replacing traditional thermal power units to become the new main power source for the power grid. However, due to the instability of photovoltaic and wind power generation, the source-load imbalance problem in the power grid is becoming increasingly serious, and large-scale energy storage equipment is urgently needed to participate in the peak and frequency regulation of the power grid. Variable speed pumped storage power stations can store electrical energy on a large scale and have excellent dynamic performance. They are important equipment for energy storage in power systems. Large AC excitation motors are the core devices for energy conversion in variable speed pumped storage power stations. Their stable and dynamic equivalent circuit parameters directly affect the dynamic performance of pumped storage power stations as well as motor operation control and protection setting methods.

However, there is no equivalent circuit parameter identification method suitable for AC excitation motors at present. We can only refer to the parameter test methods of wound-rotor asynchronous motors. However, these methods have high requirements for experimental equipment, and the experimental process is complicated and dangerous, making them difficult to use in engineering. Therefore, the current method for determining the motor parameters of AC excitation motors has the problem of poor measurement effect.

Summary of the invention

Based on this, it is necessary to provide an AC excitation motor parameter test identification method, device, computer equipment, computer readable storage medium and computer program product that can improve the parameter measurement effect of the AC excitation motor in response to the above technical problems.

In a first aspect, an embodiment of the present application provides a method for testing and identifying parameters of an AC excitation motor. The method comprises:

The motor to be tested in the first circuit environment is tested according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an AC excitation motor in any rotor position;

Testing the motor to be tested in a second circuit environment according to the test signal to obtain a target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment;

Performing a magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested;

The transformed current signal is fitted with a time domain analytical expression according to a curve fitting method to obtain a fitted current time domain expression; the fitted current time domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

In one of the embodiments, a DC power supply is provided in the first circuit environment, and the motor to be tested includes the rotor and the stator;

The three-phase winding of the stator is open-circuited, the U-phase winding of the rotor is connected to the positive end of the DC power supply, and the V-phase and W-phase windings of the rotor are connected in parallel to the negative end of the DC power supply.

In one embodiment, the test signal includes a DC step voltage signal, and the step of testing the motor to be tested in the first circuit environment according to the test signal to obtain the position angle data of the rotor in the motor to be tested includes:

Inputting the DC step voltage signal to the winding of the rotor according to the DC power supply, and recording the open-circuit phase voltage of the three-phase winding of the winding of the stator according to the oscilloscope recorder in the first circuit environment;

The position angle data of the rotor in the motor to be tested is obtained by calculation based on the open-circuit phase voltage of the three-phase winding.

In one of the embodiments, a DC power supply is provided in the second circuit environment, and the motor to be tested includes the rotor and the stator;

The three-phase winding of the rotor is short-circuited in a Y-type manner, the A-phase winding of the stator is connected to the positive end of the DC power supply, and the B-phase and C-phase windings of the stator are connected in parallel to the negative end of the DC power supply.

In one embodiment, the test signal includes a DC step signal or a DC attenuation signal, and the target induced current signal includes a first induced current signal and a second induced current signal; and obtaining the target induced current signal corresponding to each current detection point in the motor to be tested under the second circuit environment includes:

The DC step signal or the DC attenuation signal is input into the winding of the stator according to the DC power supply, and the first induced current signal of the three-phase winding corresponding to the stator and the second induced current signal corresponding to the U-phase winding of the rotor are measured according to the current sensor in the motor to be tested.

In one embodiment, the method further comprises:

Performing frequency domain conversion on the fitted current time domain expression to obtain a current frequency domain expression; the current frequency domain expression is used to characterize the calculation relationship between various coefficients and various motor parameters;

The current frequency domain expression is solved to obtain the motor parameters; the motor parameters include stator self-inductance parameters, stator transient self-inductance parameters, rotor time constant parameters, and rotor transient time constant parameters.

In a second aspect, the present application also provides an AC excitation motor parameter test identification device. The device comprises:

A first test module is used to test the motor to be tested in the first circuit environment according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an AC excitation motor in any rotor position;

A second test module is used to test the motor to be tested in a second circuit environment according to the test signal, and obtain a target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment;

A coordinate system transformation module, used for performing magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested;

The fitting and solving module is used to fit the time domain analytical expression of the transformed current signal according to the curve fitting method to obtain the fitted current time domain expression; the fitted current time domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

The motor to be tested in the first circuit environment is tested according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an AC excitation motor in any rotor position;

Testing the motor to be tested in a second circuit environment according to the test signal to obtain a target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment;

Performing a magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested;

The transformed current signal is fitted with a time domain analytical expression according to a curve fitting method to obtain a fitted current time domain expression; the fitted current time domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

In a fourth aspect, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

The motor to be tested in the first circuit environment is tested according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an AC excitation motor in any rotor position;

Testing the motor to be tested in a second circuit environment according to the test signal to obtain a target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment;

Performing a magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested;

The transformed current signal is fitted with a time domain analytical expression according to a curve fitting method to obtain a fitted current time domain expression; the fitted current time domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program, and when the computer program is executed by a processor, the following steps are implemented:

The motor to be tested in the first circuit environment is tested according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an AC excitation motor in any rotor position;

Testing the motor to be tested in a second circuit environment according to the test signal to obtain a target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment;

Performing a magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested;

The transformed current signal is fitted with a time domain analytical expression according to a curve fitting method to obtain a fitted current time domain expression; the fitted current time domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

The above-mentioned AC excitation motor parameter test identification method, device, computer equipment, storage medium and computer program product first test the motor to be tested in a first circuit environment according to the test signal to obtain the position angle data of the rotor in the motor to be tested, and then test the motor to be tested in a second circuit environment according to the test signal to obtain the target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment, and then transform the target induced current signal into a magnetic axis coordinate system to obtain the transformed current signal corresponding to any axis of the motor to be tested, and finally fit the transformed current signal with a time domain analytical expression according to the curve fitting method to obtain the fitted current time domain expression; the complexity of the test of the parameter test method of the wound asynchronous motor is avoided, the test can be carried out when the rotor is in any position, the rotor pre-positioning process is avoided, and the dynamic parameters of the AC excitation motor can be determined through only two tests, which reduces the requirements for test equipment conditions, improves the safety and convenience of the test process, improves the applicability of the measurement method in engineering practice, and improves the measurement effect of the motor parameters of the AC excitation motor.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic flow chart of a method for testing and identifying parameters of an AC excitation motor in one embodiment;

FIG2 is a schematic flow chart of a method for testing and identifying parameters of an AC excitation motor in another embodiment;

FIG3 is a schematic diagram of a first circuit environment in one embodiment;

FIG4 is a schematic diagram of a second circuit environment in one embodiment;

FIG5 is a structural block diagram of an AC excitation motor parameter test identification device in one embodiment;

FIG. 6 is a diagram showing the internal structure of a computer device in one embodiment.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

In one embodiment, as shown in FIG1 , a method for testing and identifying parameters of an AC excitation motor is provided. This embodiment uses the method applied to a terminal as an example for illustration. It is understandable that the method can also be applied to a server, and can also be applied to a system including a terminal and a server, and is implemented through the interaction between the terminal and the server. In this embodiment, the method includes the following steps:

S101, testing a motor to be tested in a first circuit environment according to a test signal to obtain position angle data of a rotor in the motor to be tested.

The test signal in step S101 may be a DC step voltage signal, which is input into the rotor winding of the motor to be tested, so as to test the motor to be tested. The first circuit environment refers to the circuit environment required for the rotor position angle test. The motor to be tested is an AC excitation motor in any rotor position, and generally, the motor is a large AC excitation motor.

The position angle of the rotor in the motor to be tested refers to the rotational position of the motor rotor relative to the stator measured by sensors or other methods, usually expressed in electrical degrees. Accurate measurement of the rotor position angle can help determine the direction of the motor magnetic field, achieve precise control, and diagnose motor faults.

S102, testing the motor to be tested in the second circuit environment according to the test signal to obtain a target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment.

The test signal in step S102 may be a DC step or DC attenuation signal, which is input into the stator winding of the motor to be tested to test the motor to be tested. The second circuit environment refers to the circuit environment required for the DC signal input static test. The target induced current signal includes a first induced current signal of the three-phase winding corresponding to the stator, and a second induced current signal corresponding to the U-phase winding of the rotor.

S103, performing magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested.

The magnetic axis coordinate system transformation is also called dq coordinate change, and any axis can be the d axis or the q axis. The transformed current signal includes the d axis current i _d or the q axis current i _q .

S104, performing time domain analytical expression fitting on the transformed current signal according to a curve fitting method to obtain a fitted current time domain expression.

The fitted current time-domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

In the above-mentioned AC excitation motor parameter test identification method, first, the motor to be tested in the first circuit environment is tested according to the test signal to obtain the position angle data of the rotor in the motor to be tested, and then the motor to be tested in the second circuit environment is tested according to the test signal to obtain the target induced current signal corresponding to each current detection point in the motor to be tested in the second circuit environment, and then the target induced current signal is transformed into a magnetic axis coordinate system to obtain the transformed current signal corresponding to any axis of the motor to be tested, and finally the transformed current signal is fitted with a time domain analytical expression according to the curve fitting method to obtain the fitted current time domain expression; the complexity of the parameter test method of the wound asynchronous motor is avoided, the test can be carried out when the rotor is in any position, the rotor pre-positioning process is avoided, and the dynamic parameters of the AC excitation motor can be determined through only two tests, which reduces the requirements for test equipment conditions, improves the safety and convenience of the test process, improves the applicability of the measurement method in engineering practice, and improves the measurement effect of the motor parameters of the AC excitation motor.

In one embodiment, a DC power supply is provided in a first circuit environment, and the motor to be tested includes a rotor and a stator; wherein the three-phase winding of the stator is open, the U-phase winding of the rotor is connected to the positive terminal of the DC power supply, and the V-phase and W-phase windings of the rotor are connected in parallel to the negative terminal of the DC power supply.

Exemplarily, the test equipment includes a DC voltage source, a current sensor, a recorder, and a voltmeter. The contents of the rotor position angle test include: opening the three-phase stator winding, connecting the rotor U-phase winding to the positive end of the DC power supply, and connecting the V-phase and W-phase windings in parallel to the negative end of the power supply.

In this embodiment, a rotor position angle test is performed on the motor to be tested by constructing a first circuit environment, thereby ensuring the feasibility of the rotor position angle test and providing conditions for obtaining subsequent test data.

In one embodiment, the test signal includes a DC step voltage signal, and the motor to be tested in the first circuit environment is tested according to the test signal to obtain the position angle data of the rotor in the motor to be tested, including:

A DC step voltage signal is input to the rotor winding according to the DC power supply, and the open-circuit phase voltage of the three-phase winding of the stator winding is recorded according to the recorder in the first circuit environment; the position angle data of the rotor in the motor to be tested is calculated according to the open-circuit phase voltage of the three-phase winding.

Exemplarily, the content of the rotor position angle test also includes: inputting a DC step voltage signal to the rotor winding from a DC power supply, and recording the open-circuit phase voltage of the three-phase windings A, B, and C of the stator winding by an oscilloscope.

In the wiring mode of the first circuit environment, the rotor position angle and the three-phase voltage satisfy:

Among them, _ua , _ub , _uc are the open-circuit voltages of the stator A, B, C three-phase windings respectively, and θ is the rotor position angle.

In this embodiment, a DC step voltage signal is first input to the rotor winding according to a DC power supply, and the open-circuit phase voltage of the three-phase winding of the stator winding is recorded according to the recorder in the first circuit environment. Then, the position angle data of the rotor in the motor to be tested is calculated based on the open-circuit phase voltage of the three-phase winding; the signal of the rotor winding is input through a DC step voltage signal, and the open-circuit phase voltage of the three-phase winding is collected by a recorder, thereby completing the calculation of the position angle, which is convenient for the subsequent calculation of the motor parameters according to the position angle.

In one embodiment, a DC power supply is provided in the second circuit environment, and the motor to be tested includes a rotor and a stator; wherein the three-phase winding of the rotor is short-circuited in a Y-type manner, the A-phase winding of the stator is connected to the positive terminal of the DC power supply, and the B-phase and C-phase windings of the stator are connected in parallel to the negative terminal of the DC power supply.

Exemplarily, the test equipment includes a DC voltage source, a current sensor, an oscilloscope, and a voltmeter. The contents of the DC signal input static test include: short-circuiting the rotor U, V, and W three-phase windings in a Y-type manner, connecting the stator A-phase winding to the positive terminal of the DC power supply, and connecting the B-phase and C-phase windings in parallel to the negative terminal of the DC power supply.

In this embodiment, a second circuit environment is constructed to perform a DC signal input static test on the motor to be tested, thereby ensuring the feasibility of the DC signal input static test and providing conditions for obtaining subsequent test data.

In one embodiment, obtaining a target induced current signal corresponding to each current detection point in the motor to be tested under the second circuit environment includes:

A DC step signal or a DC attenuation signal is input into the stator winding according to the DC power supply, and a first induced current signal of the three-phase winding corresponding to the stator and a second induced current signal corresponding to the U-phase winding of the rotor are measured according to the current sensor in the motor to be tested.

Wherein, the test signal includes a DC step signal or a DC attenuation signal, and the target induced current signal includes a first induced current signal and a second induced current signal;

Exemplarily, the content of the DC signal input static test also includes: a DC power supply inputs a DC step or DC attenuation signal into the stator winding, and a current sensor is used to measure the induced current signals in the stator A, B, C three-phase windings and the rotor U-phase winding.

In this embodiment, a test signal is first input into the stator winding according to a DC power supply, and then a first induced current signal and a second induced current signal are measured according to a current sensor in the motor to be tested; the signal of the stator winding is input through the test signal, and the first induced current signal and the second induced current signal are collected using the current sensor, so as to facilitate the subsequent calculation of the motor parameters.

In one embodiment, the method further includes: performing frequency domain conversion on the fitted current time domain expression to obtain a current frequency domain expression; and solving the current frequency domain expression to obtain motor parameters.

The frequency domain conversion may be a Laplace transform, and the current frequency domain expression is used to characterize the calculation relationship between various coefficients and various motor parameters.

Exemplarily, the frequency domain expression is:

Solving the motor parameters yields:

The motor parameters include stator self-inductance parameter L _s , stator transient self-inductance parameter L _s ^' , rotor time constant parameter _Tr , and rotor transient time constant parameter _Tr ^' . _rs is the armature circuit resistance.

In this embodiment, the fitted current time domain expression is first converted into the frequency domain to obtain the current frequency domain expression, and then the current frequency domain expression is solved to obtain the motor parameters, thereby achieving accurate calculation of the motor parameters.

In another embodiment, as shown in FIG3 , a method for testing and identifying parameters of an AC excitation motor is provided, comprising the following steps:

S301, inputting a DC step voltage signal to the rotor winding according to a DC power supply, and recording the open-circuit phase voltage of the three-phase winding of the stator winding according to an oscilloscope.

S302, obtaining the position angle data of the rotor in the motor to be tested according to the open-circuit phase voltage of the three-phase winding.

S303, inputting a DC step signal or a DC attenuation signal into the stator winding according to the DC power supply, and measuring and obtaining a target induced current signal according to the current sensor in the motor to be measured.

S304, performing magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested.

S305, fitting the time domain analytical expression of the transformed current signal according to the curve fitting method to obtain a fitted current time domain expression.

S306, performing frequency domain conversion on the fitted current time domain expression to obtain a current frequency domain expression.

S307, solving the current frequency domain expression to obtain the motor parameters.

It should be noted that the specific limitations of the above steps can be found in the specific limitations of an AC excitation motor parameter test identification method mentioned above, which will not be repeated here.

The embodiment of the present application provides a method for testing and identifying parameters of an AC excitation motor. To facilitate the understanding of those skilled in the art, FIG3 provides a schematic diagram of the principle of a first circuit environment, also known as a wiring diagram of a rotor position angle measurement test, and FIG4 provides a schematic diagram of the principle of a second circuit environment, also known as a wiring diagram of a DC step signal input static test. The following refers to FIG3 and FIG4 to describe the method for testing and identifying parameters of an AC excitation motor in detail with a specific embodiment. It is worth understanding that the following description is only an exemplary description and not a specific limitation to the application.

The AC excitation motor parameter test identification method provided in the present application is also called an AC excitation motor parameter identification test method based on DC step voltage input under arbitrary rotor position, which is used for parameter measurement of large AC excitation motors. Its purpose is to solve the problem that there is no suitable equivalent circuit parameter test identification method for existing large AC excitation motors.

The present application provides an AC excitation motor parameter test identification method, and the test equipment for the parameter identification test includes: a DC voltage source, a current sensor, a recorder, and a voltmeter. The parameter identification test mainly consists of two parts of tests, namely, a rotor position angle positioning test (also known as a rotor position angle positioning test, a rotor position angle test) and a DC signal input static test (also known as a DC signal input static test, a DC step signal input test, a DC step signal input static test).

The contents of the rotor position angle test include: opening the three-phase stator winding, connecting the U-phase winding of the rotor to the positive terminal of the DC power supply, connecting the V-phase and W-phase windings in parallel to the negative terminal of the power supply, inputting a DC step voltage signal from the DC power supply to the rotor winding, and recording the open-circuit phase voltage of the three-phase windings A, B, and C of the stator windings with an oscilloscope.

The specific wiring method is shown in Figure 3. Under this wiring method, the rotor position angle and the three-phase voltage satisfy:

Among them, _ua , _ub , _uc are the open-circuit voltages of the stator A, B, C three-phase windings respectively, and θ is the rotor position angle.

In addition, the DC signal input static test includes: short-circuiting the rotor U, V, W three-phase windings in a Y-type manner, connecting the stator A-phase winding to the positive end of the DC power supply, and connecting the B-phase and C-phase windings in parallel to the negative end of the DC power supply. The DC power supply inputs a DC step or DC attenuation signal to the stator winding, and uses a current sensor to measure the induced current signals in the stator A, B, C three-phase windings and the rotor U-phase winding.

The overall process of the AC excitation motor parameter test identification method provided in the present application can be as follows: according to the position angle obtained by the rotor position angle positioning test, the stator A, B, and C three-phase induced currents obtained by the DC signal input static experiment record are subjected to dq coordinate changes to obtain the d-axis current i _d and q-axis current i _q of the AC excitation motor, and the d-axis current i _d and q-axis current i _q are fitted with time domain analytical expressions by using a curve fitting method, and according to the current time domain expression results, the AC excitation motor parameter identification results are obtained after further processing.

Specifically, firstly, the stator A, B, C three-phase induced currents obtained by the DC signal input static experiment record are transformed into dq coordinates according to the position angle obtained by the rotor position angle positioning test, and the d-axis current i _d and q-axis current i _q of the AC excitation motor are obtained.

The change process satisfies:

Wherein, id and iq are the d-axis current and q-axis current of the AC excitation motor respectively, ia, ib and ic are the stator A, B and C three-phase induced currents obtained by the DC signal input static experiment record respectively, and θ is the rotor position angle obtained by the rotor position angle positioning test.

Then, the time domain analytical expressions of the d-axis current i _d and the q-axis current i _q are fitted by using the curve fitting method. Since the d-axis and q-axis magnetic circuits of large AC excitation motors are symmetrical and the d-axis and q-axis equivalent circuits are the same, the time domain analytical expressions of the d-axis current i _d and the q-axis current i _q are the same, with only a difference in sign, which does not affect the parameter identification results, and one of them can be selected for expression fitting.

Taking the d-axis current as an example, when the DC signal is input into the static test and the DC step signal is input, the stator d-axis current time domain expression and the rotor d-axis current time domain expression are respectively;

Wherein, C ₁ , C ₂ , D ₁ , D ₂ are amplitude coefficients, λ ₁ , λ ₂ are attenuation coefficients, and i _dw is the steady-state value of the d-axis current. Since the selected d-axis axis coincides with the rotor U-phase winding axis, the rotor d-axis current i _rd (t) is equal to the rotor U-phase winding current i _u (t).

Finally, according to the result of the current time domain expression, the AC excitation motor parameter identification result is obtained after further processing, including:

The stator d-axis current time domain expression i _sd (t) and the rotor d-axis current i _rd (t) are Laplace transformed to obtain the frequency domain expression:

The coefficients of the frequency domain expression satisfy:

Where, _Ls is the stator self-inductance, _Ls ^' is the stator transient self-inductance, _Tr is the rotor time constant, _Tr ^' is the rotor transient time constant, and _rs is the armature circuit resistance.

The obtained stator and rotor d-axis currents are fitted using the curve fitting method to obtain the amplitude coefficient and attenuation coefficient of the d-axis current and the excitation winding current. After Laplace transformation, the motor parameters are solved. Among them, the relationship between the motor parameters and the coefficients in the Laplace transformation formula is:

The motor parameters obtained include: _Ls is the stator self-inductance; _Ls ^' is the stator transient self-inductance; _Tr is the rotor time constant; _Tr ^' is the rotor transient time constant; _rs is the armature circuit resistance.

In addition, it should be noted that Mutual inductance and self inductance represent the mutual inductance between the stator and the rotor; It represents the flux self-inductance in the motor system, which is the result obtained by subtracting the mutual self-inductance from the stator self-inductance. The flux self-inductance refers to the self-inductance caused by the magnetic field in the motor, which can also be understood as the influence of the magnetic flux in the magnetic field on the current. By calculating and analyzing the flux self-inductance, engineers can better optimize the motor design and make accurate performance predictions and adjustments. This combined parameter is used to describe the dynamic response characteristics of the motor system. Its numerical value reflects the comprehensive influence of the motor system's inductance, resistance and response speed. It can evaluate the dynamic characteristics of the motor system, such as response speed, stability, etc., and further guide the design and tuning of the motor controller. is the rotor resistance, which indicates the resistance value of the motor rotor circuit.

The acquisition of motor parameters in the AC excitation motor parameter test identification method provided in this application can help engineers to have a deeper understanding of the working principle and performance characteristics of the motor, and then realize applications such as motor performance analysis, control design, fault diagnosis and optimization design, providing important support for the optimization and improvement of the motor system.

The AC excitation motor parameter test identification method provided in the present application can be tested when the rotor is in any position, avoiding the rotor pre-positioning process. The dynamic parameters of the AC excitation motor can be determined through only two tests. The requirements for test equipment are low, the test process is safe and simple, and it is more suitable for engineering practice.

It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

Based on the same inventive concept, the embodiment of the present application also provides an AC excitation motor parameter test identification device for implementing the AC excitation motor parameter test identification method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more AC excitation motor parameter test identification device embodiments provided below can refer to the limitations of the AC excitation motor parameter test identification method above, and will not be repeated here.

In one embodiment, as shown in FIG5 , an AC excitation motor parameter test identification device is provided, comprising: a first test module 501, a second test module 502, a coordinate system transformation module 503, and a fitting solution module 504, wherein:

The first test module 501 is used to test the motor to be tested in the first circuit environment according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an AC excitation motor in any rotor position;

The second test module 502 is used to test the motor under test in the second circuit environment according to the test signal, and obtain the target induced current signal corresponding to each current detection point in the motor under test in the second circuit environment;

A coordinate system transformation module 503 is used to perform magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal corresponding to any axis of the motor to be tested;

The fitting solution module 504 is used to fit the time domain analytical expression of the transformed current signal according to the curve fitting method to obtain the fitted current time domain expression; the fitted current time domain expression is used to solve the motor parameters corresponding to the motor to be tested, and the motor parameters are used to characterize the working performance of the motor to be tested.

In one embodiment, a DC power supply is provided in a first circuit environment, and the motor to be tested includes a rotor and a stator; wherein the three-phase winding of the stator is open, the U-phase winding of the rotor is connected to the positive end of the DC power supply, and the V-phase and W-phase windings of the rotor are connected in parallel to the negative end of the DC power supply.

In one embodiment, the device is used to: input a DC step voltage signal to the rotor winding according to a DC power supply, record the open-circuit phase voltage of the three-phase winding of the stator winding according to a recorder in a first circuit environment; and calculate the position angle data of the rotor in the motor to be tested according to the open-circuit phase voltage of the three-phase winding.

In one embodiment, a DC power supply is provided in the second circuit environment, and the motor to be tested includes a rotor and a stator; wherein the three-phase winding of the rotor is short-circuited in a Y-type manner, the A-phase winding of the stator is connected to the positive terminal of the DC power supply, and the B-phase and C-phase windings of the stator are connected in parallel to the negative terminal of the DC power supply.

In one embodiment, the device is used to: input a DC step signal or a DC attenuation signal into the stator winding according to a DC power supply, and measure the first induced current signal of the three-phase winding corresponding to the stator and the second induced current signal corresponding to the U-phase winding of the rotor according to the current sensor in the motor to be tested.

In one embodiment, the device is used to: perform frequency domain conversion on the fitted current time domain expression to obtain a current frequency domain expression; the current frequency domain expression is used to characterize the calculation relationship between various coefficients and various motor parameters; solve the current frequency domain expression to obtain motor parameters; the motor parameters include stator self-inductance parameters, stator transient self-inductance parameters, rotor time constant parameters, and rotor transient time constant parameters.

Each module in the above-mentioned AC excitation motor parameter test identification device can be implemented in whole or in part by software, hardware and their combination. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the corresponding operations of each of the above modules.

In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be shown in FIG6. The computer device includes a processor, a memory, an input/output interface, a communication interface, a display unit, and an input device. The processor, the memory, and the input/output interface are connected via a system bus, and the communication interface, the display unit, and the input device are connected to the system bus via the input/output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input/output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for testing and identifying parameters of an AC excitation motor is implemented.

Those skilled in the art will understand that the structure shown in FIG. 6 is merely a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

In one embodiment, a computer device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the steps in the above method embodiments are implemented.

In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present application. It should be noted that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims (10)

1. An alternating current excitation motor parameter test identification method is characterized by comprising the following steps:

testing a motor to be tested in a first circuit environment according to a test signal to obtain position angle data of a rotor in the motor to be tested; the motor to be tested is an alternating current excitation motor at any rotor position;

Testing the motor to be tested in a second circuit environment according to the test signal to obtain target induced current signals corresponding to current detection points in the motor to be tested in the second circuit environment;

performing magnetic axis coordinate system transformation on the target induced current signal to obtain a transformed current signal of the motor to be tested corresponding to any axis;

Performing time domain analysis expression fitting on the transformed current signal according to a curve fitting method to obtain a fitted current time domain expression; the fitted current time domain expression is used for solving and obtaining motor parameters corresponding to the motor to be tested, and the motor parameters are used for representing the working performance of the motor to be tested.

2. The method of claim 1, wherein a dc power source is disposed in the first circuit environment, the motor to be tested comprising the rotor and stator;

the three-phase winding of the stator is open, the U-phase winding of the rotor is connected to the positive end of the direct current power supply, and the V-phase winding and the W-phase winding of the rotor are connected in parallel and then connected to the negative end of the direct current power supply.

3. The method of claim 2, wherein the test signal comprises a dc step voltage signal, and wherein the testing the motor under test in the first circuit environment based on the test signal results in the position angle data of the rotor in the motor under test, comprising:

Inputting the direct-current step voltage signal to the winding of the rotor according to the direct-current power supply, and recording the open-circuit phase voltage of the three-phase winding of the stator according to a wave recorder in the first circuit environment;

and calculating to obtain position angle data of a rotor in the motor to be tested according to the open-circuit phase voltage of the three-phase winding.

4. The method of claim 1, wherein a dc power source is disposed in the second circuit environment, the motor to be tested comprising the rotor and stator;

the three-phase windings of the rotor are short-circuited in a Y-type mode, the A-phase winding of the stator is connected to the positive end of the direct current power supply, and the B-phase winding and the C-phase winding of the stator are connected in parallel and then connected to the negative end of the direct current power supply.

5. The method of claim 4, wherein the test signal comprises a dc step signal or a dc decay signal, and the target induced current signal comprises a first induced current signal and a second induced current signal; the obtaining the target induced current signal corresponding to each current detection point in the motor to be detected in the second circuit environment includes:

and the direct current step signal or the direct current attenuation signal is input into the windings of the stator according to the direct current power supply, and the first induced current signal of the three-phase winding corresponding to the stator and the second induced current signal corresponding to the U-phase winding of the rotor are obtained through measurement according to a current sensor in the motor to be tested.

6. The method according to claim 1, wherein the method further comprises:

performing frequency domain conversion on the fitted current time domain expression to obtain a current frequency domain expression; the current frequency domain expression is used for representing the calculation relation between each coefficient and each motor parameter;

Solving the current frequency domain expression to obtain the motor parameters; the motor parameters comprise stator self-inductance parameters, stator transient self-inductance parameters, rotor time constant parameters and rotor transient time constant parameters.

7. An ac excitation motor parameter test identification device, the device comprising:

The first test module is used for testing the motor to be tested in the first circuit environment according to the test signal to obtain the position angle data of the rotor in the motor to be tested; the motor to be tested is an alternating current excitation motor at any rotor position;

The second test module is used for testing the motor to be tested in a second circuit environment according to the test signal to obtain target induced current signals corresponding to current detection points in the motor to be tested in the second circuit environment;

The coordinate system transformation module is used for carrying out magnetic axis coordinate system transformation on the target induction current signal to obtain a transformed current signal of the motor to be tested corresponding to any axis;

The fitting solving module is used for performing time domain analysis expression fitting on the transformed current signals according to a curve fitting method to obtain fitted current time domain expressions; the fitted current time domain expression is used for solving and obtaining motor parameters corresponding to the motor to be tested, and the motor parameters are used for representing the working performance of the motor to be tested.

8. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any of claims 1 to 6 when the computer program is executed.

9. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 6.