Permanent magnet synchronous motor inductance calibration method and device and computer equipment

Abstract

The invention relates to a permanent magnet synchronous motor inductance calibration method and device and computer equipment. For each calibration working condition, measuring target calibration data of the to-be-tested motor under the target current test point in the first calibration time period; the target calibration data comprises DC-axis voltage, DC-axis current and motor torque; measuring the zero-current quadrature-axis voltage of the to-be-tested motor at the zero-current test point in a second calibration time period continuous with the first calibration time period; on the basis of the inductance parameter model, the target calibration data and the zero-current quadrature-axis voltage, inductance calibration data of the to-be-tested motor under the calibration working condition are calculated; inductance calibration errors caused by resistance drift due to stator temperature change are effectively avoided; meanwhile, interference of permanent magnet flux linkage drift caused by rotor temperature change on inductance calibration is effectively suppressed; under the condition that accurate temperature control is not needed, high-efficiency, wide-temperature and high-precision inductance parameter calibration is achieved.

Description

Technical Field

[0001] This application relates to the field of motor technology, and in particular to a method, apparatus and computer equipment for calibrating the inductance of a permanent magnet synchronous motor. Background Technology

[0002] As a complex control unit characterized by nonlinearity, strong coupling, and multiple variables, the permanent magnet synchronous motor exhibits nonlinear changes in inductance during control due to variations in the right-angle shaft current, resulting in magnetic saturation and cross-coupling effects. These changes in inductance directly impact motor control performance. In traditional inductance calibration techniques, to accurately obtain the motor's inductance values ​​at different operating points, the effects of stator and rotor temperature variations on winding resistance and permanent magnet flux linkage must be considered. Traditional calibration methods typically require strict control of the motor's stator and rotor temperatures within a narrow range to minimize measurement errors caused by parameter drift. However, this leads to time-consuming and inefficient calibration processes. Ignoring temperature variations and treating resistance and flux linkage as constant parameters results in significant deviations between the calibrated and actual inductance values, affecting control accuracy.

[0003] There is currently no effective solution to the problems of traditional calibration techniques, which require strict control of the motor stator and rotor temperatures, resulting in limited calibration temperature range, long calibration cycle, and low efficiency. Summary of the Invention

[0004] Therefore, it is necessary to provide a method, apparatus, and computer equipment for calibrating the inductance of a permanent magnet synchronous motor to address the aforementioned technical problems.

[0005] In a first aspect, this application provides a method for calibrating the inductance of a permanent magnet synchronous motor, the method comprising:

[0006] For each calibration condition, during the first calibration period, the target calibration data of the motor under test at the target current test point are measured; the target calibration data includes the right-angle axis voltage, right-angle axis current, and motor torque;

[0007] During a second calibration period that is consecutive to the first calibration period, the zero-current quadrature-axis voltage of the motor under test is measured at the zero-current test point.

[0008] Based on the inductance parameter model, the target calibration data, and the zero-current quadrature-axis voltage, the inductance calibration data of the motor under test under the calibration conditions are calculated.

[0009] In one embodiment, each calibration condition has a corresponding target current test point; the target current test point is located within a preset current limit circle corresponding to the motor under test; the step of measuring the target calibration data of the motor under test at the target current test point during the first calibration period includes:

[0010] During the first calibration period, current control is performed on the motor under test based on the target current test point;

[0011] When the operating state of the motor under test reaches the preset stable condition, the target calibration data of the motor under test is measured at the target current test point.

[0012] In one embodiment, measuring the zero-current quadrature-axis voltage of the motor under test at a zero-current test point during a second calibration period that is continuous with the first calibration period includes:

[0013] During the second calibration period, current control is performed on the motor under test based on the zero-current test point;

[0014] When the motor under test reaches a preset stable operating condition, the zero-current quadrature-axis voltage of the motor under test is measured at the zero-current test point.

[0015] In one embodiment, the method for constructing the inductance parameter model includes:

[0016] Obtain the motor torque model, the flux linkage model in the rotating coordinate system, and the voltage model in the rotating coordinate system;

[0017] Based on the right-angle current, the voltage model is reorganized to construct a differential voltage model;

[0018] The differential voltage model and the motor torque model are solved together to obtain the analytical solution of the orthogonal axis flux linkage;

[0019] The flux linkage model and the analytical solution of the orthogonal axis flux linkage are jointly solved to obtain the inductance parameter model; the inductance parameter model includes the orthogonal axis inductance parameter model and the quadrature axis inductance parameter model.

[0020] In one embodiment, the step of reorganizing the variables of the voltage model based on the orthogonal axis current to construct a differential voltage model includes:

[0021] Based on the right-angle and quadrature-axis currents, the voltage model is equivalently processed to obtain the right-angle equivalent voltage model and the quadrature-axis equivalent voltage model;

[0022] Differential calculations are performed on the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model to obtain a differential voltage model.

[0023] In one embodiment, the orthogonal axis current includes a direct-axis current and a quadrature axis current; the voltage model includes a quadrature axis voltage model and a direct-axis voltage model; the step of performing equivalent processing on the voltage model based on the orthogonal axis current to obtain a direct-axis equivalent voltage model and a quadrature axis equivalent voltage model includes:

[0024] Based on the direct-axis current, the quadrature-axis voltage model is equivalently processed to obtain the quadrature-axis equivalent voltage model;

[0025] Based on the quadrature-axis current, the direct-axis voltage model is equivalently processed to obtain the direct-axis equivalent voltage model.

[0026] In one embodiment, calculating the inductance calibration data of the motor under test under the calibration conditions based on the inductance parameter model, the target calibration data, and the zero-current quadrature-axis voltage includes:

[0027] Based on the voltage model in the rotating coordinate system and the zero-current quadrature-axis voltage, the target permanent magnet flux of the motor under test is calculated under the calibration conditions.

[0028] Based on the inductance parameter model, the target calibration data, and the target permanent magnet flux linkage, the inductance calibration data of the motor under test under the calibration conditions are calculated.

[0029] In one embodiment, the voltage model includes a quadrature-axis voltage model and a direct-axis voltage model; the calculation of the target permanent magnet flux linkage of the motor under test under the calibration condition based on the voltage model in the rotating coordinate system and the zero-current quadrature-axis voltage includes:

[0030] Substituting the zero-current quadrature-axis voltage into the quadrature-axis voltage model, the direct-axis flux linkage of the motor under test under the calibration conditions is obtained.

[0031] Obtain the direct-axis flux linkage model in a rotating coordinate system;

[0032] Substituting the direct-axis flux linkage into the direct-axis flux linkage model, the target permanent magnet flux linkage of the motor under test under the calibration conditions is obtained.

[0033] In one embodiment, calculating the inductance calibration data of the motor under test under the calibration conditions based on the inductance parameter model, the target calibration data, and the target permanent magnet flux linkage includes:

[0034] Obtain the operating status parameters corresponding to the motor under test;

[0035] Based on the operating state parameters, the right-angle axis voltage, the right-angle axis current, the motor torque, and the target permanent magnet flux linkage, the inductance parameter model is solved to obtain the inductance calibration data of the motor under test under the calibration conditions.

[0036] The inductance calibration data includes direct-axis inductance data and quadrature-axis inductance data.

[0037] Secondly, this application provides an inductance calibration device for a permanent magnet synchronous motor, the device comprising:

[0038] The first measurement module is used to measure the target calibration data of the motor under test at the target current test point within a first calibration period for each calibration condition; the target calibration data includes the right-angle axis voltage, right-angle axis current and motor torque;

[0039] The second measurement module is used to measure the zero-current quadrature-axis voltage of the motor under test at the zero-current test point during a second calibration period that is continuous with the first calibration period.

[0040] The inductance calculation module is used to calculate the inductance calibration data of the motor under test under the calibration conditions based on the inductance parameter model, the target calibration data, and the zero-current quadrature-axis voltage.

[0041] Thirdly, this application provides a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the method described above.

[0042] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described above.

[0043] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described above.

[0044] The aforementioned permanent magnet synchronous motor inductance calibration method, apparatus, and computer equipment, for each calibration condition, measure the target calibration data of the motor under test at the target current test point during the first calibration period; the target calibration data includes the direct- and quadrature-axis voltage, the direct- and quadrature-axis current, and the motor torque; during the second calibration period, which is continuous with the first calibration period, measure the zero-current quadrature-axis voltage of the motor under test at the zero-current test point; and calculate the inductance calibration data of the motor under test under the calibration condition based on the inductance parameter model, the target calibration data, and the zero-current quadrature-axis voltage. By setting consecutive first and second calibration periods under each calibration condition, the direct-axis voltage, direct-axis current, and motor torque at the target current test point are collected during the first calibration period. By adopting an inductance calibration method that does not rely on stator phase resistance as an input parameter, the inductance calibration error caused by resistance drift due to stator temperature changes is effectively avoided. At the same time, the zero-current quadrature-axis voltage is measured at the zero-current test point during the second calibration period, which can effectively suppress the interference of permanent magnet flux drift caused by rotor temperature changes on the inductance calibration. Based on this, high-efficiency, wide-temperature, and high-precision inductance parameter calibration is achieved without the need for precise temperature control. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a flowchart illustrating a method for calibrating the inductance of a permanent magnet synchronous motor in one embodiment.

[0047] Figure 2 This is a schematic diagram of the second quadrant of a preset current limiting circle in one embodiment;

[0048] Figure 3 This is a flowchart illustrating the steps involved in constructing an inductor parameter model in one embodiment.

[0049] Figure 4 This is a flowchart illustrating the calculation steps for inductor calibration data in one embodiment;

[0050] Figure 5 This is a structural block diagram of a permanent magnet synchronous motor inductance calibration device in one embodiment;

[0051] Figure 6 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0053] As a complex system characterized by nonlinearity, strong coupling, and multiple variables, the inductance characteristics of a permanent magnet synchronous motor undergo significant nonlinear changes during operation due to factors such as magnetic saturation and cross-coupling effects, as the direct axis (d-axis) and quadrature axis (q-axis) currents change. The accuracy of the inductance parameters directly affects the dynamic response and steady-state performance of the motor control system.

[0054] To accurately obtain the inductance value of a motor at different operating points, the influence of stator and rotor temperature changes on winding resistance and permanent magnet flux linkage must be considered during calibration. Traditional calibration methods typically require strict control of the motor's stator and rotor temperatures within a small range to reduce measurement errors caused by parameter drift, but this results in a time-consuming and inefficient calibration process. If temperature changes are ignored and resistance and flux linkage are treated as constant parameters, the calibrated inductance value will deviate significantly from the actual value, affecting control accuracy.

[0055] To address the aforementioned issues, this application proposes a method for calibrating the inductance of a permanent magnet synchronous motor. This method aims to reduce the impact of motor stator and rotor temperatures on inductance calibration, achieving high-efficiency, wide-temperature, and high-precision inductance parameter calibration without the need for precise temperature control.

[0056] In one embodiment, such as Figure 1 As shown, Figure 1 This is a flowchart illustrating a permanent magnet synchronous motor inductor calibration method in one embodiment; the permanent magnet synchronous motor inductor calibration method includes the following steps:

[0057] Step S101: For each calibration condition, within the first calibration period, measure the target calibration data of the motor under test at the target current test point.

[0058] Each calibration condition has a corresponding target current test point; the target current test point is used to apply a specific right-angle shaft current value to the motor under test; the target current test point is located within the preset current limit circle corresponding to the motor under test to ensure that it does not exceed the safe operating boundary of the motor under test.

[0059] The preset current limit circle refers to the current operating boundary defined in the orthogonal axis current coordinate system, used to limit the motor's operation within a safe current range. The preset current limit circle is related to the driving performance of the motor under test and is not specifically limited here. In an exemplary embodiment, a partial schematic diagram of the preset current limit circle is shown below. Figure 2As shown, Figure 2 The black dots inside the current limiting circle represent current test points. It can be understood that each current test point can be used as a target current test point. In the actual calibration process, it is necessary to select the corresponding current test point as the target current test point according to the specific calibration requirements. No specific restrictions are made here.

[0060] It should be noted that the target current test point is a non-zero current test point, that is, the direct-axis current value and the quadrature-axis current value corresponding to the target current test point are not 0.

[0061] It is understood that the method for determining current test points may include, but is not limited to: using a fixed orthogonal axis current step size and uniformly distributing the points within a preset current limit circle; or, distributing the points non-uniformly within a preset current limit circle according to the key areas of the motor control strategy. It is understood that the method for determining current test points needs to be selected according to actual needs, and no specific limitation is made here.

[0062] The first calibration period refers to the time period during which the motor under test operates at the target current test point in each calibration condition.

[0063] The target calibration data includes right-angle and right-angle axis voltages, right-angle and right-angle axis currents, and motor torque. The right-angle and right-angle axis voltages include both direct-axis and quadrature-axis voltages; the right-angle and right-angle axis currents include both direct-axis and quadrature-axis currents. It should be noted that the right-angle and right-angle axis voltages, right-angle and right-angle axis currents, and motor torque are all input parameters for the inductance parameter model.

[0064] Step S102: During the second calibration period, which is continuous with the first calibration period, measure the zero-current quadrature-axis voltage of the motor under test at the zero-current test point.

[0065] The second calibration period refers to the continuous time period immediately following the first calibration period. The zero-current quadrature-axis voltage refers to the quadrature-axis voltage measured at the zero-current test point, that is, the quadrature-axis voltage measured under test conditions where both the direct-axis current and the quadrature-axis current are 0.

[0066] It should be noted that the specific duration settings of the first and second calibration periods should ensure that the motor under test can achieve steady-state operation at both the target current test point and the zero current test point. At the same time, the duration of the first and second calibration periods should be as short as possible to suppress the accumulation of temperature rise in the motor stator and rotor, so that the thermal state changes are within the allowable range throughout the calibration process, thereby ensuring the consistency of the permanent magnet flux linkage between the first and second calibration periods.

[0067] Understandably, by setting the first and second calibration periods to be executed consecutively, the target calibration data and zero-current quadrature-axis voltage can be acquired within a time window when the motor's thermal state changes relatively little, making the stator and rotor temperatures approximately the same in both periods. Under this condition, it can be reasonably estimated that the permanent magnet flux linkage at the zero-current test point in the second calibration period is the same as that at the target current test point in the first calibration period. Furthermore, by measuring the zero-current quadrature-axis voltage at the zero-current test point, the permanent magnet flux linkage under the current calibration condition can be calculated. This not only avoids introducing stator phase resistance during the entire calibration process but also avoids inductance calibration errors caused by rotor temperature changes leading to permanent magnet flux linkage drift.

[0068] Step S103: Based on the inductance parameter model, target calibration data, and zero-current quadrature-axis voltage, calculate the inductance calibration data of the motor under test under calibration conditions.

[0069] The inductance parameter model refers to the mathematical model used to describe the relationship between motor inductance and the direct-axis and quadrature-axis voltages, currents, and torque. The inductance parameter model includes both direct-axis and quadrature-axis inductance parameter models; the inductance calibration data includes both direct-axis and quadrature-axis inductance data.

[0070] It should be noted that the inductance parameter model in this application does not rely on the stator phase resistance as an input parameter, which ensures that the inductance parameter solution process fundamentally avoids the calibration error caused by the drift of winding resistance due to stator temperature changes.

[0071] For example, a dynamometer is used to establish a drag platform, which includes a test motor and the motor under test. During inductance calibration, a field-oriented control motor is used to drag the motor under test to a constant speed, the speed range of which can be set to 0.2-1 times the rated speed of the motor under test. Further, for each calibration condition, a target current test point corresponding to the calibration condition is selected. Based on the target current test point, a corresponding control command is issued from the dynamometer platform to the motor under test to measure the direct-acting and quadrature-axis voltages of the motor under test at the target current test point during the first calibration period. The right-angle shaft current and motor torque are used as target calibration data. After the target calibration data is measured, immediately in the second calibration period, which is continuous with the first calibration period, the corresponding control command is sent to the motor under test on the dynamometer platform based on the zero-current test point to measure the zero-current quadrature shaft voltage of the motor under test at the zero-current test point. Furthermore, the target calibration data and the zero-current quadrature shaft voltage are used as input parameters of the inductance parameter model, and the right-angle shaft inductance calibration data of the motor under test under the calibration conditions are calculated based on the inductance parameter model.

[0072] In this embodiment, by setting consecutive first and second calibration periods under each calibration condition, the direct-axis voltage, direct-axis current, and motor torque at the target current test point are collected during the first calibration period. By adopting an inductance calibration method that does not rely on stator phase resistance as an input parameter, the inductance calibration error caused by resistance drift due to stator temperature changes is effectively avoided. At the same time, the zero-current quadrature-axis voltage is measured at the zero-current test point during the second calibration period, which can effectively suppress the interference of permanent magnet flux drift caused by rotor temperature changes on the inductance calibration. Based on this, high-efficiency, wide-temperature, and high-precision inductance parameter calibration is achieved without the need for precise temperature control.

[0073] In one embodiment, measuring the target calibration data of the motor under test at the target current test point during the first calibration period includes the following steps:

[0074] Step 1: During the first calibration period, perform current control on the motor under test based on the target current test point.

[0075] Step 2: When the motor under test reaches the preset stable operating conditions, measure the target calibration data of the motor under test at the target current test point.

[0076] Among them, the preset stability condition is used to ensure that the motor under test has entered steady-state operation, that is, the fluctuations of key parameters such as right-angle shaft current, voltage, speed and torque are within the allowable error range, thereby ensuring the accuracy of the collected data.

[0077] It should be noted that the preset stability conditions need to be set reasonably according to the actual performance parameters of the motor under test, and no specific restrictions are imposed here.

[0078] For example, based on the target current test point, the corresponding control command is issued to the dynamometer platform to control the current of the motor under test. After the operating state of the motor under test reaches the preset stable condition, the target calibration data under this operating condition is continuously recorded several times within a time Ts, that is, the d-axis voltage u. d q-axis voltage u q d-axis current i d q-axis current i q and motor torque T e The motor torque can be detected, but is not limited to, using a torque sensor. It should be noted that the time Ts is shorter than, but included within, the first calibration period. The value of Ts should be as small as possible, for example, less than or equal to 1 second.

[0079] In this embodiment, during the first calibration period, the current of the motor under test is controlled based on the target current test point. Before measurement, it is determined whether the motor under test has reached the preset stability condition. After the preset stability condition is met, the target calibration data of the motor under test at the target current test point is measured. This ensures the safety of the inductor calibration process and the accuracy and reliability of data acquisition, laying a data foundation for the calibration of inductor parameters under calibration conditions.

[0080] In one embodiment, measuring the zero-current quadrature-axis voltage of the motor under test at a zero-current test point during a second calibration period that is continuous with the first calibration period includes the following steps:

[0081] Step 1: During the second calibration period, perform current control on the motor under test based on the zero current test point.

[0082] Step 2: When the motor under test reaches the preset stable operating conditions, measure the zero-current quadrature-axis voltage of the motor under test at the zero-current test point.

[0083] For example, immediately after the target calibration data measurement is completed, in the second calibration period that is consecutive to the first calibration period, based on the zero-current test point, the corresponding control command is issued on the dynamometer platform to control the current of the motor under test. After the operating state of the motor under test reaches the preset stable condition, the zero-current quadrature-axis voltage, i.e., the q-axis voltage u, is quickly and continuously recorded several times within a time Ts. q It should be noted that the Ts time is shorter than the second calibration period and is included within the second calibration period. The value of Ts should be as small as possible, for example, less than or equal to 1 second.

[0084] In this embodiment, during the second calibration period, which is continuous with the first calibration period, the current of the motor under test is controlled based on the zero-current test point. Before measurement, it is determined whether the motor under test has reached the preset stability condition. After the preset stability condition is met, the zero-current quadrature-axis voltage of the motor under test at the zero-current test point is measured. This ensures the safety of the inductance calibration process and the accuracy and reliability of data acquisition. It lays the data foundation for the accurate calculation of the permanent magnet flux linkage under the calibration conditions and avoids the influence of rotor temperature changes on the inductance calibration results.

[0085] In one embodiment, such as Figure 3 As shown, Figure 3 This is a flowchart illustrating the steps involved in constructing an inductor parameter model in one embodiment; the method for constructing the inductor parameter model includes the following steps:

[0086] Step S301: Obtain the motor torque model, the flux linkage model in the rotating coordinate system, and the voltage model in the rotating coordinate system.

[0087] The mathematical expression for the motor torque model is shown in formula (1):

[0088] (1);

[0089] in, This refers to the motor torque; This refers to the d-axis flux linkage, i.e., the direct-axis flux linkage. This is the q-axis flux linkage, i.e., the quadrature-axis flux linkage; i is the number of pole pairs of the motor; d This refers to the d-axis current, i.e., the direct-axis current; i q This is the q-axis current, i.e., the quadrature-axis current.

[0090] The mathematical expression for the magnetic flux linkage model in the rotating coordinate system is shown in formula (2):

[0091] (2);

[0092] in, This refers to the d-axis flux linkage, i.e., the direct-axis flux linkage. The flux linkage is the q-axis flux linkage, i.e., the quadrature-axis flux linkage; i d This refers to the d-axis current, i.e., the direct-axis current; i q This refers to the q-axis current, i.e., the quadrature-axis current. It is the q-axis inductance, i.e., the quadrature-axis inductance; It is the d-axis inductance, i.e., the direct-axis inductance; It is a permanent magnet flux linkage.

[0093] The mathematical expression of the voltage model in the rotating coordinate system is shown in formula (3). It should be noted that the voltage model in the rotating coordinate system is the voltage model in steady state.

[0094] (3);

[0095] in, Let be the electric angular velocity, and its calculation formula is: ;u d This is the d-axis voltage, i.e., the direct-axis voltage; u q This is the q-axis voltage, i.e., the quadrature-axis voltage; R s For stator phase resistance; i d This refers to the d-axis current, i.e., the direct-axis current; i q This refers to the q-axis current, i.e., the quadrature-axis current. This refers to the d-axis flux linkage, i.e., the direct-axis flux linkage. The flux linkage is the q-axis flux linkage, i.e., the quadrature-axis flux linkage; n r n is the motor speed; p This represents the number of pole pairs of the motor.

[0096] Step S302: Based on the orthogonal axis current, the voltage model is reorganized to construct a differential voltage model.

[0097] Among them, the right-axis current includes the right-axis current and the quadrature-axis current.

[0098] The differential voltage model is used to eliminate the stator phase resistance term in order to avoid the influence of resistance drift caused by stator temperature changes on inductor calibration.

[0099] It should be noted that, according to the voltage model (i.e., steady-state voltage model) shown in formula (3), it can be concluded that the voltage model includes the stator phase resistance R. s Item; By constructing a differential voltage model, the stator phase resistance R can be... s This eliminates the issue, making the inductor calibration process independent of the stator phase resistance, thereby suppressing errors caused by stator temperature changes.

[0100] The purpose of reorganizing the variables in the voltage model is to eliminate susceptible parameters (i.e., stator phase resistance) by reorganizing the relationships between variables in the voltage model, thereby constructing a new model more suitable for inductor parameter calibration and improving the robustness and accuracy of inductor calibration. In other words, it involves recombining the various terms in the voltage model to make the original model, which included the stator phase resistance R, more robust. s The terms are canceled out in the new equation, thus constructing a system independent of the stator phase resistance R. s The differential voltage model avoids resistance drift errors caused by stator temperature changes.

[0101] In one exemplary embodiment, variable recombination processing may include, but is not limited to, equivalent processing and differential processing. Based on the orthogonal axis current, variable recombination processing is performed on the voltage model to construct a differential voltage model, including the following steps:

[0102] Step 1: Based on the direct-axis and quadrature-axis currents, perform equivalent processing on the voltage model to obtain the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model.

[0103] Step 2: Perform differential calculations on the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model to obtain the differential voltage model.

[0104] The direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model have the same parameter terms; among these, the stator phase resistance R is included. s The purpose of performing differential calculations on the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model is to eliminate identical parameter terms, thereby completely eliminating terms containing stator phase resistance Rs, and obtaining the corresponding differential voltage model.

[0105] In an exemplary embodiment, step 1, based on the direct-axis and quadrature-axis currents, performs equivalent processing on the voltage model to obtain a direct-axis equivalent voltage model and a quadrature-axis equivalent voltage model, including the following steps:

[0106] Step 1.1: Based on the direct-axis current, the quadrature-axis voltage model is equivalently processed to obtain the quadrature-axis equivalent voltage model.

[0107] Step 1.2: Based on the quadrature-axis current, the direct-axis voltage model is equivalently processed to obtain the direct-axis equivalent voltage model.

[0108] For example, based on formula (3), the quadrature-axis voltage model is: The direct-axis voltage model is Based on direct-axis current The quadrature-axis voltage model is then subjected to equivalent processing to obtain the quadrature-axis equivalent voltage model as follows: Based on quadrature axis current The direct-axis voltage model is then subjected to equivalent processing to obtain the direct-axis equivalent voltage model as follows: Therefore, it can be concluded that the common parameter terms of the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model are " ".

[0109] Furthermore, differential calculations are performed on the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model to obtain the differential voltage model as shown in formula (4).

[0110] (4);

[0111] in, Let be the electric angular velocity, and its calculation formula is: ;u d This is the d-axis voltage, i.e., the direct-axis voltage; u q This refers to the q-axis voltage, i.e., the quadrature-axis voltage; i d This refers to the d-axis current, i.e., the direct-axis current; i q This refers to the q-axis current, i.e., the quadrature-axis current. This refers to the d-axis flux linkage, i.e., the direct-axis flux linkage. The flux linkage is the q-axis flux linkage, i.e., the quadrature-axis flux linkage; n r n is the motor speed; p This represents the number of pole pairs of the motor.

[0112] Step S303: Perform joint solution processing on the differential voltage model and the motor torque model to obtain the analytical solution of the orthogonal axis flux linkage.

[0113] The analytical solutions for orthogonal axis flux linkages include analytical solutions for direct-axis flux linkages and analytical solutions for quadrature-axis flux linkages. It can be understood that the analytical solutions for orthogonal axis flux linkages represent explicit expressions for the orthogonal axis flux linkages.

[0114] For example, the differential voltage model and the motor torque model are solved together, that is, the equations (4) and (2) are combined to obtain the analytical solution of the orthogonal axis flux linkage as shown in equation (5).

[0115] (5)

[0116] in, This is an analytical solution for direct-axis magnetic flux linkage; This is an analytical solution for the cross-axis magnetic flux linkage. Let be the electric angular velocity, and its calculation formula is: ;u d This is the d-axis voltage, i.e., the direct-axis voltage; u q This refers to the q-axis voltage, i.e., the quadrature-axis voltage; i d This refers to the d-axis current, i.e., the direct-axis current; i q This refers to the q-axis current, i.e., the quadrature-axis current. This refers to the d-axis flux linkage, i.e., the direct-axis flux linkage. The flux linkage is the q-axis flux linkage, i.e., the quadrature-axis flux linkage; n r n is the motor speed; p This represents the number of pole pairs of the motor. This represents the motor torque.

[0117] Step S304: The flux linkage model and the analytical solution of the orthogonal axis flux linkage are jointly solved to obtain the inductance parameter model.

[0118] The inductance parameter model includes the direct-axis inductance parameter model and the quadrature-axis inductance parameter model.

[0119] For example, the flux linkage model and the analytical solution of the orthogonal axis flux linkage are solved together, that is, the equations (2) and (5) are combined to obtain the inductance parameter model as shown in equation (6).

[0120] (6);

[0121] in, This is a parameter model for a direct-axis inductor; This is a parameter model for quadrature-axis inductors; Let be the electric angular velocity, and its calculation formula is: ;u d This is the d-axis voltage, i.e., the direct-axis voltage; u q This refers to the q-axis voltage, i.e., the quadrature-axis voltage; i d This refers to the d-axis current, i.e., the direct-axis current; i q This refers to the q-axis current, i.e., the quadrature-axis current. This refers to the d-axis flux linkage, i.e., the direct-axis flux linkage. The flux linkage is the q-axis flux linkage, i.e., the quadrature-axis flux linkage; n r n is the motor speed; p This represents the number of pole pairs of the motor. This refers to the motor torque; It is a permanent magnet flux linkage.

[0122] It should be noted that when calculating the inductor calibration data based on the inductor parameter model shown in formula (6), the quadrature-axis voltage measured in the first calibration period is substituted into u in formula (6). q The zero-current quadrature-axis voltage measured during the second calibration period was used to calculate the permanent magnet flux linkage. .

[0123] It should be noted that by setting the first and second calibration periods to be executed continuously, this application can complete the acquisition of target calibration data and zero-current quadrature-axis voltage within a time window where the thermal state of the motor changes little, making the stator and rotor temperatures approximately the same in both periods. Under this condition, it can be reasonably estimated that the permanent magnet flux linkage at the zero-current test point in the second calibration period is the same as that at the target current test point in the first calibration period. Furthermore, by measuring the zero-current quadrature-axis voltage at the zero-current test point, the permanent magnet flux linkage under the current calibration condition can be calculated. Based on this, not only can the stator phase resistance be avoided during the entire calibration process, but also the inductance calibration error caused by the permanent magnet flux drift due to rotor temperature changes can be avoided.

[0124] It is understandable that the direct-axis currents corresponding to the zero-current test points are all 0. Therefore, the zero-current test point and the zero-current quadrature-axis voltage are substituted into the quadrature-axis voltage model. and direct-axis flux linkage model The permanent magnet flux linkage under the current calibration conditions can then be calculated. .

[0125] Furthermore, it should be noted that the above inductance parameter model, i.e., formula (6), cannot satisfy... Direct-axis inductance at 0A The calculation, and When the quadrature axis inductance is 0A The fundamental reason for the calculation lies in the existence of parameters in the inductance model. or The term in the denominator causes the mathematical expression to fail under zero current conditions. However, due to... = Under low current conditions (0A), the cross-coupling effect of the motor is weak, and the inductance changes relatively smoothly; that is, the inductance change is not significant at low currents. Based on this characteristic, the inductance calibration results from nearby non-zero current test points can be used as a reasonable substitute. For example, when it is necessary to obtain the inductance calibration data from a zero-current test point, the inductance calibration data calculated from a right-angle axis current of 4A (or other close but non-zero current test points) can be used as an approximation to achieve complete inductance mapping across the entire current range.

[0126] In this embodiment, based on the right-angle axis current, the voltage model undergoes variable recombination to construct a differential voltage model, eliminating stator phase resistance-related terms. This eliminates the need for stator phase resistance parameters during inductor calibration, fundamentally avoiding the resistance drift caused by stator temperature changes. Furthermore, by jointly solving the differential voltage model and the motor torque model, an analytical solution for the right-angle axis flux linkage is obtained. Then, the flux linkage model is jointly solved with the analytical solution for the right-angle axis flux linkage to construct an inductor parameter model, achieving an explicit analytical solution for the inductance value. Based on this, strict temperature control is unnecessary during actual calibration, effectively shortening the calibration cycle and improving calibration efficiency. This lays the foundation for achieving wide-temperature, high-precision, and high-efficiency inductor calibration.

[0127] In one embodiment, such as Figure 4 As shown, Figure 4 This is a flowchart illustrating the calculation steps for inductance calibration data in one embodiment. Based on the inductance parameter model, target calibration data, and zero-current quadrature-axis voltage, the inductance calibration data of the motor under test under calibration conditions is calculated, including the following steps:

[0128] Step S401: Based on the voltage model in the rotating coordinate system and the zero-current quadrature-axis voltage, calculate the target permanent magnet flux linkage of the motor under test under calibration conditions.

[0129] It should be noted that the stator and rotor temperatures are approximately the same during the first and second calibration periods. Under these conditions, it can be reasonably estimated that the permanent magnet flux linkage at the zero-current test point during the second calibration period is the same as that at the target current test point during the first calibration period. Based on this, this application selects to measure the zero-current quadrature-axis voltage at the zero-current test point and calculate the target permanent magnet flux linkage of the motor under test under calibration conditions to ensure that the inductance calibration error caused by the drift of the permanent magnet flux linkage due to rotor temperature changes can be effectively avoided, while also avoiding the introduction of stator phase resistance.

[0130] In an exemplary embodiment, based on the voltage model in a rotating coordinate system and the zero-current quadrature-axis voltage, the target permanent magnet flux linkage of the motor under test under calibration conditions is calculated, including the following steps:

[0131] Step 1: Substitute the zero-current quadrature-axis voltage into the quadrature-axis voltage model to obtain the direct-axis flux linkage of the motor under test under calibration conditions.

[0132] Step 2: Obtain the direct-axis flux linkage model in the rotating coordinate system.

[0133] Step 3: Substitute the direct-axis flux linkage into the direct-axis flux linkage model to obtain the target permanent magnet flux linkage of the motor under test under calibration conditions.

[0134] For example, the zero-current quadrature-axis voltage and the zero-current test point ( Substitute into the quadrature axis voltage model The direct-axis flux linkage of the motor under test under calibration conditions was obtained. Furthermore, the direct-axis magnetic flux... Substitute into the direct-axis flux linkage model ,in, The magnetic flux linkage of the target permanent magnet of the motor under test under calibrated conditions is obtained. .

[0135] Step S402: Based on the inductance parameter model, target calibration data, and target permanent magnet flux linkage, calculate the inductance calibration data of the motor under test under calibration conditions.

[0136] In an exemplary embodiment, based on the inductance parameter model, target calibration data, and target permanent magnet flux linkage, the inductance calibration data of the motor under test under calibration conditions is calculated, including the following steps:

[0137] Step 1: Obtain the operating status parameters of the motor under test.

[0138] The operating status parameters include at least the motor speed and the number of motor pole pairs; it can be understood that the operating status parameters are all known and directly obtainable data.

[0139] Step 2: Based on the operating state parameters, right-angle shaft voltage, right-angle shaft current, motor torque, and target permanent magnet flux linkage, solve the inductance parameter model to obtain the inductance calibration data of the motor under test under calibration conditions.

[0140] The inductance calibration data includes direct-axis inductance data and quadrature-axis inductance data.

[0141] For example, obtain the operating state parameters (e.g., motor speed, number of motor pole pairs) of the motor under test, and substitute the operating state parameters, right-angle shaft voltage, right-angle shaft current, motor torque and target permanent magnet flux linkage into the inductance parameter model, i.e., the above formula (6), to solve and obtain the right-angle inductance data and quadrature shaft inductance data of the motor under test under the calibration conditions.

[0142] In this embodiment, based on the zero-current quadrature-axis voltage at the zero-current test point, the target permanent magnet flux linkage of the motor under test is calculated under calibration conditions. This effectively avoids inductance calibration errors introduced by permanent magnet flux linkage drift caused by rotor temperature changes, while also avoiding the introduction of stator phase resistance. Furthermore, based on operating state parameters, right-angle-axis voltage, right-angle-axis current, motor torque, and target permanent magnet flux linkage, the inductance parameter model is solved to obtain the inductance calibration data of the motor under test under calibration conditions. This achieves high-efficiency, wide-temperature, and high-precision inductance parameter calibration without the need for precise temperature control.

[0143] In one specific embodiment, the inductance calibration method for the permanent magnet synchronous motor of this application was actually tested, and the evaluation environment is described below:

[0144] This example uses a 10-pole permanent magnet synchronous motor. The motor has a rated speed of 2500 rpm, a current limit circle of 56A, and a current calibration step size of 4A. The inductance is calibrated at 1000 rpm. The stator temperature range is 25~105℃, and the rotor temperature is not measured or controlled.

[0145] As shown in Table 1, the direct-axis current i corresponding to the target current test point is... d = -8A, quadrature axis current i q Taking 20A as an example, during the first calibration period, current control is performed on the motor under test based on the target current test point. After the operating state of the motor under test reaches the preset stable condition, the target calibration data is continuously sampled and recorded 4 times (recorded in sequence from number 1 to number 4). The target calibration data includes: d-axis voltage u d q-axis voltage u q d-axis current i d q-axis current i q The motor torque T detected by the torque sensor e During the second calibration period, which is consecutive to the first calibration period, current control is applied to the motor under test based on the zero-current test point. After the motor under test reaches the preset stable operating condition, the zero-current quadrature-axis voltage, i.e., the q-axis voltage u, is continuously sampled and recorded four times (in sequence from number 5 to number 8). q .

[0146] In Table 1, i d For direct-axis current, i q For quadrature-axis current, u d For direct-axis voltage, u q For quadrature axis voltage, T rq This is the actual measured motor torque.

[0147] Table 1

[0148]

[0149] Based on the inductance parameter model, i.e., the derivation of formula (6), the direct-axis inductance L is calculated as follows: d = 60.15uH, quadrature axis inductance L q = 57.94uH.

[0150] Furthermore, based on the permanent magnet synchronous motor inductance calibration method described in the above embodiments, the test data (including target calibration data and zero-current quadrature-axis voltage) under each calibration condition are batch processed to obtain the right-angle-axis inductance calibration data as shown in Tables 2 and 3. Table 2 shows the d-axis inductance value calculated by the method of this application; Table 3 shows the q-axis inductance value calculated by the method of this application.

[0151] Table 2

[0152]

[0153] Table 3

[0154]

[0155] Furthermore, to verify the effectiveness of the permanent magnet synchronous motor inductance calibration method of this application, the following two sets of control experiments were set up:

[0156] Control Experiment 1:

[0157] Based on the experimental data of motor stator and rotor temperatures over a wide temperature range in Tables 2 and 3 above, and according to the traditional method, i.e., formula (3), the phase resistance R was measured using an instrument at room temperature of 25℃ before the experiment. s =50.22mΩ, the permanent magnet flux linkage =4.751mT is taken as a constant, and the calculation results are shown in Tables 4 and 5. Table 4 is the d-axis inductance value calculated by the traditional scheme (stator temperature 25~105℃); Table 5 is the q-axis inductance value calculated by the traditional scheme (stator temperature 25~105℃).

[0158] Table 4

[0159]

[0160] Table 5

[0161]

[0162] In control experiment one, L d The average value and L calculated by the method described in this application d The error of the average value is 3.02uH, L q The average value and L calculated by the method described in this application q The average error is 2.79uH.

[0163] Control Experiment 2:

[0164] The motor stator temperature is controlled between 25 and 55°C. Since the rotor temperature cannot be directly measured, inductance calibration is indirectly ensured by repeatedly measuring the back electromotive force during calibration intervals, ensuring the deviation does not exceed ±2% of the initial measurement. The inductance is then recalibrated under conditions where the rotor temperature variation is minimal. Before calibration begins, the motor windings are heated to the 25-45°C range, and the phase resistance R is measured using a digital bridge. s= 50.42mΩ; The permanent magnet flux linkage was calculated by the dynamometer based on the back electromotive force of the test motor. =4.75mT. According to formula (3), the resistance and magnetic flux are substituted into the formula as constants, and the calculation results are shown in Table 6 and Table 7. Table 6 is the d-axis inductance value calculated by the traditional scheme (stator temperature 25~55℃); Table 7 is the q-axis inductance value calculated by the traditional scheme (stator temperature 25~55℃).

[0165] Table 6

[0166]

[0167] Table 7

[0168]

[0169] In control experiment two, L d The average value and L calculated by the method described in this application d The error of the average value is 1.91uH, L q The average value and L calculated by the method described in this application q The average error is 1.44uH.

[0170] The above experimental results confirm that the inductance calibration method of the permanent magnet synchronous motor in this application has a smaller difference in inductance results compared with the conventional calibration scheme of the control group two (25~55℃ stator and rotor temperature). However, the calibration process of the control group two is more complicated and takes longer.

[0171] Compared with the conventional calibration scheme of 25~105℃ stator and rotor temperature, the inductance calibration method of permanent magnet synchronous motor in this application will cause a larger error in the calibration inductance value.

[0172] In summary, this application eliminates the need for strict control of the motor's stator and rotor temperatures, allowing calibration over a wide temperature range. This significantly reduces workload while maintaining inductance calibration accuracy, achieving a balance between efficiency and precision. It is understood that the stator resistance variable is directly eliminated in the inductance parameter model of this application, avoiding inductance calculation deviations caused by stator temperature changes in resistance. Furthermore, since rotor temperature is difficult to detect, this application sets continuous first and second calibration periods. After each calibration of a target current test point, the current is immediately reset to zero, and the q-axis voltage (zero-current quadrature-axis voltage) is recorded. This allows the calculation of the current target permanent magnet flux linkage value based on the voltage and flux linkage models, thus eliminating the need to consider the influence of rotor temperature on the permanent magnet flux linkage.

[0173] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0174] Based on the same inventive concept, this application also provides a permanent magnet synchronous motor inductance calibration device for implementing the aforementioned permanent magnet synchronous motor inductance calibration method. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of one or more permanent magnet synchronous motor inductance calibration device embodiments provided below can be found in the limitations of the permanent magnet synchronous motor inductance calibration method described above, and will not be repeated here.

[0175] In one exemplary embodiment, such as Figure 5 As shown, a permanent magnet synchronous motor inductance calibration device is provided, including: a first measurement module 501, a second measurement module 502, and an inductance calculation module 503, wherein:

[0176] The first measurement module 501 is used to measure the target calibration data of the motor under test at the target current test point within a first calibration period for each calibration condition; the target calibration data includes the right-angle axis voltage, right-angle axis current and motor torque.

[0177] The second measurement module 502 is used to measure the zero-current quadrature-axis voltage of the motor under test at the zero-current test point during a second calibration period that is continuous with the first calibration period.

[0178] The inductance calculation module 503 is used to calculate the inductance calibration data of the motor under test under the calibration conditions based on the inductance parameter model, the target calibration data and the zero current quadrature axis voltage.

[0179] The aforementioned permanent magnet synchronous motor inductor calibration device sets consecutive first and second calibration periods under each calibration condition. During the first calibration period, it collects the direct-axis voltage, direct-axis current, and motor torque at the target current test point. By employing an inductor calibration method that does not rely on stator phase resistance as an input parameter, it effectively avoids inductor calibration errors caused by resistance drift due to stator temperature changes. Simultaneously, during the second calibration period, it measures the zero-current quadrature-axis voltage at the zero-current test point, effectively suppressing the interference of permanent magnet flux drift caused by rotor temperature changes on inductor calibration. Based on this, it achieves high-efficiency, wide-temperature, and high-precision inductor parameter calibration without the need for precise temperature control.

[0180] In one embodiment, each calibration condition has a corresponding target current test point; the target current test point is located within a preset current limit circle corresponding to the motor under test; the first measurement module 501 is further used for:

[0181] During the first calibration period, current control is performed on the motor under test based on the target current test point;

[0182] When the motor under test reaches the preset stable operating conditions, measure the target calibration data of the motor under test at the target current test point.

[0183] In one embodiment, the second measurement module 502 is used for:

[0184] During the second calibration period, current control is performed on the motor under test based on the zero current test point;

[0185] When the motor under test reaches the preset stable operating conditions, measure the zero-current quadrature-axis voltage of the motor under test at the zero-current test point.

[0186] In one embodiment, the permanent magnet synchronous motor inductance calibration device further includes a model building module, which is used for:

[0187] Obtain the motor torque model, the flux linkage model in the rotating coordinate system, and the voltage model in the rotating coordinate system;

[0188] Based on the right-angle current, the voltage model is reorganized to construct a differential voltage model;

[0189] By jointly solving the differential voltage model and the motor torque model, an analytical solution for the orthogonal axis flux linkage is obtained.

[0190] The flux linkage model and the analytical solution of the orthogonal axis flux linkage are jointly solved to obtain the inductance parameter model; the inductance parameter model includes the orthogonal axis inductance parameter model and the quadrature axis inductance parameter model.

[0191] In one embodiment, the model building module is also used for:

[0192] Based on the right-angle and quadrature-axis currents, the voltage model is equivalently processed to obtain the right-angle equivalent voltage model and the quadrature-axis equivalent voltage model;

[0193] Differential calculations are performed on the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model to obtain the differential voltage model.

[0194] In one embodiment, the direct-axis and quadrature-axis currents include direct-axis currents and quadrature-axis currents; the voltage model includes a quadrature-axis voltage model and a direct-axis voltage model; the model building module is also used for:

[0195] Based on the direct-axis current, the quadrature-axis voltage model is equivalently processed to obtain the quadrature-axis equivalent voltage model;

[0196] Based on the quadrature-axis current, the direct-axis voltage model is equivalently processed to obtain the direct-axis equivalent voltage model.

[0197] In one embodiment, the inductance calculation module 503 is further configured to:

[0198] Based on the voltage model in the rotating coordinate system and the zero-current quadrature-axis voltage, the magnetic flux of the target permanent magnet of the motor under test is calculated under the calibration conditions.

[0199] Based on the inductance parameter model, target calibration data, and target permanent magnet flux linkage, the inductance calibration data of the motor under test is calculated under calibration conditions.

[0200] In one embodiment, the voltage model includes a quadrature-axis voltage model and a direct-axis voltage model; the inductance calculation module 503 is also used for:

[0201] Substituting the zero-current quadrature-axis voltage into the quadrature-axis voltage model, we obtain the direct-axis flux linkage of the motor under test under calibration conditions.

[0202] Obtain the direct-axis flux linkage model in a rotating coordinate system;

[0203] Substituting the direct-axis flux linkage into the direct-axis flux linkage model, the target permanent magnet flux linkage of the motor under test is obtained under calibration conditions.

[0204] In one embodiment, the inductance calculation module 503 is further configured to:

[0205] Obtain the operating status parameters corresponding to the motor under test;

[0206] Based on the operating state parameters, right-angle axis voltage, right-angle axis current, motor torque, and target permanent magnet flux linkage, the inductance parameter model is solved to obtain the inductance calibration data of the motor under test under calibration conditions.

[0207] The inductance calibration data includes direct-axis inductance data and quadrature-axis inductance data.

[0208] Each module in the aforementioned permanent magnet synchronous motor inductance calibration device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0209] In one exemplary embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 6 As shown, the computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores data related to the calibration of permanent magnet synchronous motor inductors. The I / O interfaces are used for information exchange between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for calibrating the inductors of a permanent magnet synchronous motor.

[0210] Those skilled in the art will understand that Figure 6 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0211] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0212] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0213] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0214] 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, data stored, data displayed, 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 the relevant data must comply with relevant regulations.

[0215] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory 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), magnetic 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. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0216] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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 application.

[0217] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for inductance calibration of a permanent magnet synchronous motor, characterized in that, The method comprises: For each calibration condition, measuring target calibration data of the motor to be tested at a target current test point in a first calibration period; the target calibration data comprises direct-axis voltage, quadrature-axis voltage, direct-axis current and quadrature-axis current; In a second calibration period continuous with the first calibration period, measuring zero-current quadrature-axis voltage of the motor to be tested at a zero-current test point; Based on an inductance parameter model, the target calibration data and the zero-current quadrature-axis voltage, calculating inductance calibration data of the motor to be tested under the calibration condition.

2. The method of claim 1, wherein, There is a corresponding target current test point for each calibration condition; the target current test point is located within a preset current limit circle of the motor to be tested; The method for measuring target calibration data of the motor to be tested at a target current test point in a first calibration period comprises: In the first calibration period, performing current control on the motor to be tested based on the target current test point; In the case where the operating state of the motor to be tested reaches a preset stable condition, measuring target calibration data of the motor to be tested at a target current test point.

3. The method of claim 1, wherein, The method for measuring zero-current quadrature-axis voltage of the motor to be tested at a zero-current test point in a second calibration period continuous with the first calibration period comprises: In the second calibration period, performing current control on the motor to be tested based on the zero-current test point; In the case where the operating state of the motor to be tested reaches a preset stable condition, measuring zero-current quadrature-axis voltage of the motor to be tested at a zero-current test point.

4. The method of claim 1, wherein, The method for constructing the inductance parameter model comprises: Obtaining a motor torque model, a flux linkage model in a rotating coordinate system and a voltage model in a rotating coordinate system; Based on the direct-axis current and quadrature-axis current, performing variable reorganization processing on the voltage model to construct a differential voltage model; Jointly solving the differential voltage model and the motor torque model to obtain an analytical solution of direct-axis and quadrature-axis flux linkages; Jointly solving the flux linkage model and the analytical solution of direct-axis and quadrature-axis flux linkages to obtain an inductance parameter model; the inductance parameter model comprises a direct-axis inductance parameter model and a quadrature-axis inductance parameter model.

5. The method of claim 4, wherein, The method for constructing the differential voltage model based on the direct-axis current and quadrature-axis current comprises: Based on the direct-axis current and quadrature-axis current, performing equivalent processing on the voltage model to obtain a direct-axis equivalent voltage model and a quadrature-axis equivalent voltage model; Performing differential calculation on the direct-axis equivalent voltage model and the quadrature-axis equivalent voltage model to obtain a differential voltage model.

6. The method of claim 5, wherein, The direct-axis current and quadrature-axis current comprise direct-axis current and quadrature-axis current; the voltage model comprises a quadrature-axis voltage model and a direct-axis voltage model; the method for obtaining a direct-axis equivalent voltage model and a quadrature-axis equivalent voltage model based on the direct-axis current and quadrature-axis current comprises: Based on the direct-axis current, performing equivalent processing on the quadrature-axis voltage model to obtain a quadrature-axis equivalent voltage model; Based on the quadrature-axis current, performing equivalent processing on the direct-axis voltage model to obtain a direct-axis equivalent voltage model.

7. The method of claim 1 or claim 4, wherein, The inductance calibration data of the motor to be tested under the calibration condition is calculated based on the inductance parameter model, the target calibration data, and the zero-current cross-axis voltage. The target permanent magnet flux linkage of the motor to be tested under the calibration condition is calculated based on the voltage model in the rotating coordinate system and the zero-current cross-axis voltage. The inductance calibration data of the motor to be tested under the calibration condition is calculated based on the inductance parameter model, the target calibration data, and the target permanent magnet flux linkage.

8. The method of claim 7, wherein, The voltage model includes a cross-axis voltage model and a direct-axis voltage model; the target permanent magnet flux linkage of the motor to be tested under the calibration condition is calculated based on the voltage model in the rotating coordinate system and the zero-current cross-axis voltage, including: The zero-current cross-axis voltage is substituted into the cross-axis voltage model to obtain the direct-axis flux linkage of the motor to be tested under the calibration condition; A direct-axis flux linkage model in the rotating coordinate system is obtained; The direct-axis flux linkage is substituted into the direct-axis flux linkage model to obtain the target permanent magnet flux linkage of the motor to be tested under the calibration condition.

9. The method of claim 7, wherein, The inductance calibration data of the motor to be tested under the calibration condition is calculated based on the inductance parameter model, the target calibration data, and the target permanent magnet flux linkage, including: An operating state parameter corresponding to the motor to be tested is obtained; The inductance parameter model is solved based on the operating state parameter, the direct and cross-axis voltages, the direct and cross-axis currents, the motor torque, and the target permanent magnet flux linkage to obtain the inductance calibration data of the motor to be tested under the calibration condition; The inductance calibration data includes direct-axis inductance data and cross-axis inductance data.

10. A permanent magnet synchronous motor inductance calibration device, characterized in that, The device includes: A first measurement module is configured to measure, for each calibration condition, target calibration data of a motor to be tested at a target current test point within a first calibration period; the target calibration data includes direct and cross-axis voltages, direct and cross-axis currents, and a motor torque; A second measurement module is configured to measure a zero-current cross-axis voltage of the motor to be tested at a zero-current test point within a second calibration period continuous with the first calibration period; An inductance calculation module is configured to calculate inductance calibration data of the motor to be tested under the calibration condition based on an inductance parameter model, the target calibration data, and the zero-current cross-axis voltage. 11.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-10. The processor executes the computer program to implement the steps of the method of any one of claims 1 to 9.

12. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 9.

13. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 9.

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