A rapid calibration method for permanent magnet synchronous motors in new energy vehicles
By performing rapid calibration of permanent magnet synchronous motors within the base speed range, and utilizing automated programs and real-time temperature monitoring, the problems of excessively high motor temperature and poor accuracy caused by high-speed calibration in existing technologies have been solved, achieving efficient and accurate motor parameter calibration.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHIXIN TECH CO LTD
- Filing Date
- 2023-07-14
- Publication Date
- 2026-05-26
AI Technical Summary
Existing calibration methods for permanent magnet synchronous motors require high speed and high current, which leads to excessively high motor temperature, long calibration cycles, low efficiency, poor torque control accuracy, and safety risks.
A rapid calibration method is adopted in the base speed range, including calibration of the maximum torque-current ratio, motor flux linkage and inductance comparison table. Parameters are input through an automated program, motor temperature is monitored in real time, high-speed conditions are reduced, and multiple average samplings are used to improve the accuracy of torque acquisition.
It achieves automated and efficient motor calibration, reduces the need for high speed, lowers temperature differences, improves calibration accuracy and torque control accuracy, and shortens calibration time.
Smart Images
Figure CN117118287B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of vector control technology for permanent magnet synchronous motors, and specifically to a rapid calibration method for permanent magnet synchronous motors in new energy vehicles. Background Technology
[0002] With the development of technology, electric vehicles are gaining an increasingly larger market share. Currently, electric vehicle drive systems mainly use three-phase AC permanent magnet synchronous motors and three-phase AC asynchronous motors. Permanent magnet synchronous motors dominate the market due to their high efficiency, small size, and good NVH performance. Permanent magnet synchronous motors currently primarily employ vector control. To obtain better efficiency and torque control accuracy, the permanent magnet synchronous motor needs to be calibrated to acquire precise control parameters.
[0003] Existing methods for calibrating permanent magnet synchronous motor parameters primarily involve MTPA calibration at the base speed and current MAP calibration across the entire speed range. Current MAP calibration is performed by applying different torques at different speeds. This process requires the motor to operate under high torque and high speed conditions, which easily leads to excessively high motor temperatures. Calibration often requires waiting for the motor to cool down, resulting in long calibration cycles, low efficiency, and increased risks during high-speed operation. Furthermore, because the motor operates under high speed and high current, the temperature difference is significant, and temperature greatly affects the accuracy of the torque controller, leading to poor torque control accuracy using this method. Summary of the Invention
[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a rapid calibration method for permanent magnet synchronous motors in new energy vehicles. This method eliminates the need for the motor to operate at high speeds, reducing risks and the requirement for high-speed test benches. It also offers high calibration efficiency and high control precision.
[0005] This invention provides a rapid calibration method for permanent magnet synchronous motors in new energy vehicles, comprising the following steps:
[0006] Table for calibrating the maximum torque-to-current ratio;
[0007] Motor flux linkage calibration table;
[0008] Motor inductance calibration table;
[0009] Obtain the target torque T req And by consulting the calibrated lookup tables, the required d-axis current i to be output is obtained. dref and q-axis requested current i qref ;
[0010] The calibration maximum torque-to-current ratio lookup table includes:
[0011] Input a phase current i sAdjust the current angle θ until the motor output torque begins to decrease, then record the phase current i before the torque begins to decrease. s Current angle θ and motor output torque;
[0012] Input the next phase current i s And repeat the above operation until the final input phase current i s Greater than or equal to the motor peak current i max ;
[0013] Based on the recorded phase currents i s Given the current angle θ, calculate the corresponding direct-axis current i. d and cross-axis current i q ;
[0014] A calibration table for motor flux linkage includes:
[0015] The direct-axis current i d Set it to 0, and input different quadrature-axis currents i in sequence. q Record the cross-axis currents i q and the corresponding motor output torque, up to the final input quadrature-axis current i q Greater than or equal to the motor peak current i max ;
[0016] According to the recorded quadrature-axis current i q Calculate different quadrature-axis currents i q Corresponding motor flux
[0017] A calibration table for motor inductance includes:
[0018] Input a direct-axis current i d Values are input sequentially using multiple quadrature-axis currents i with a specified quadrature-axis current adjustment step size. q Record the current direct-axis current i d The cross-axis currents i q The corresponding motor output torque, up to the final input quadrature-axis current i q Or the calculated phase current i s Greater than or equal to the motor peak current i max ;
[0019] Input the next direct-axis current i d The value is calculated, and the above operation is repeated until the final input direct-axis current i is reached. d Greater than or equal to the motor peak current i max ;
[0020] Based on the recorded direct-axis current i d Cross-axis current i q Calculate the corresponding motor inductance Ldq .
[0021] More preferably, the step of obtaining the target torque T req And by consulting the calibrated lookup tables, the required d-axis current i to be output is obtained. dref and q-axis requested current i qref include:
[0022] Based on the target torque T req Consult the calibration lookup table to obtain the required d-axis current i to be output. dref ;
[0023] Based on the q-axis feedback current i at the previous moment qcur By consulting the calibration reference table, the target motor flux linkage can be obtained.
[0024] Based on the d-axis feedback current i from the previous moment dcur and the q-axis feedback current i at the previous moment qcur By consulting the calibration reference table, the target motor inductance L can be obtained. dq ;
[0025] Based on the target torque T req d-axis requested current i dref Target motor flux Target motor inductance L dq Calculate the required q-axis current i to be output. qref .
[0026] Preferably, the q-axis requested current i to be output at present qref Calculate using the following formula:
[0027]
[0028] Among them, P n This represents the number of pole pairs of the motor.
[0029] Preferably, the method for obtaining the motor output torque includes:
[0030] The dynamometer continuously samples torque at specified sampling intervals until the specified number of samplings is reached.
[0031] The average value of multiple collected torque data points is taken as the motor output torque.
[0032] Preferably, during the calibration of the maximum torque-current ratio lookup table, when a phase current i is input... s After a current angle θ, it also includes:
[0033] Determine the output torque of the motor;
[0034] If the current motor output torque is greater than the motor output torque at the previous moment, it is determined that the motor output torque has not yet started to decrease. At this time, the current angle θ is reduced by adjusting the step size of the specified current angle, and the motor output torque is judged again.
[0035] Repeat the above operation until the current motor output torque is less than the motor output torque at the previous moment;
[0036] If the current motor output torque is less than the motor output torque at the previous moment, it is determined that the motor output torque has started to decrease. At this time, the phase current i before the torque started to decrease is recorded. s Current angle θ and motor output torque.
[0037] Preferably, the step of recording each phase current i s Given the current angle θ, calculate the corresponding direct-axis current i. d and cross-axis current i q include:
[0038] According to the formula Calculate the corresponding direct-axis current i d and cross-axis current i q ;
[0039] The direct-axis current i corresponding to different motor output torques was fitted using curve fitting. d and cross-axis current i q .
[0040] Preferably, the motor magnetic flux Calculate using the following formula:
[0041]
[0042]
[0043] Among them, P n L is the number of pole pairs of the motor. d L is the d-axis inductance of the motor. q T is the q-axis inductance of the motor. e This refers to the output torque of the motor.
[0044] Preferably, the motor inductance L dq Calculated using the following formula:
[0045]
[0046] Among them, P n L is the number of pole pairs of the motor. d L is the d-axis inductance of the motor. q T is the q-axis inductance of the motor.e This refers to the output torque of the motor.
[0047] Preferably, the q-axis requested current i qref Calculated using the following formula:
[0048]
[0049] Among them, P n This represents the number of pole pairs of the motor.
[0050] Preferably, during the calibration process, the motor temperature is monitored in real time. When the motor temperature exceeds the set first temperature threshold, the current operating condition is unloaded until the motor temperature drops to the set second temperature threshold, at which point the previous operating condition is resumed and calibration continues.
[0051] The beneficial effects of this invention are as follows:
[0052] 1. This method automatically inputs, adjusts, records, and outputs the corresponding parameters according to the set program, enabling fully automated calibration of the test bench. Compared with the ordinary current MAP calibration method, it can save a lot of calibration work, reduce motor calibration time, and improve motor calibration efficiency. For frequent motor model changes and modifications, it can achieve rapid calibration, saving a lot of development time and improving overall development efficiency. Furthermore, this method requires less calibration data, and all operations are within the base speed range, reducing the need for high-speed calibration and saving a lot of calibration work, thus improving calibration efficiency. The calibration is fixed at a certain speed, and the speed is relatively low, with fewer high-current conditions, which can effectively reduce temperature differences. Simultaneously, the motor temperature is monitored in real time during calibration. When the motor temperature exceeds the set first temperature threshold, the current operating condition is unloaded until the motor temperature drops to the set second temperature threshold, then the previous operating condition is resumed to continue calibration, further avoiding the impact of rotor temperature rise on accuracy.
[0053] 2. Multiple average samples are taken during torque acquisition to improve the accuracy of calibration parameters and enhance the precision of software torque control. Attached Figure Description
[0054] Figure 1 A schematic diagram of a system embodiment for implementing the method of the present invention;
[0055] Figure 2 This is a schematic diagram of the method flow of the present invention;
[0056] Figure 3 This is a flowchart illustrating step 1 of the present invention;
[0057] Figure 4 This is a flowchart illustrating step 2 of the present invention;
[0058] Figure 5 This is a flowchart illustrating step 3 of the present invention;
[0059] Figure 6 This is a schematic diagram of the vector control principle of the motor controller of the present invention. Detailed Implementation
[0060] To make the technical problems, technical solutions, and beneficial effects to be solved by 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 are not intended to limit the scope of this application.
[0061] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.
[0062] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.
[0063] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.
[0064] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."
[0065] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0066] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" means "two or more."
[0067] Example 1
[0068] Figure 1 This paper illustrates a structural schematic diagram of a rapid calibration system for a permanent magnet synchronous motor in a new energy vehicle according to a preferred embodiment of this application. For ease of explanation, only the parts relevant to this embodiment are shown, and the details are as follows:
[0069] A rapid calibration system for permanent magnet synchronous motors in new energy vehicles includes a host computer on a test bench, a frequency converter, a controller, a dynamometer, and a torque sensor. The motor controller is connected to the test bench via CAN communication and is used to control the current threshold setpoint of the motor controller. The motor controller provides real-time feedback information such as motor temperature, current value, and fault status through communication, which is then provided to the host computer on the test bench for automated calibration.
[0070] Example 2
[0071] like Figure 2 As shown in the figure, this embodiment provides a rapid calibration method for permanent magnet synchronous motors in new energy vehicles, which includes the following steps:
[0072] Step 1: Calibrate the maximum torque-to-current ratio reference table;
[0073] Step 2, calibrate the motor flux linkage reference table;
[0074] Step 3, calibrate the motor inductance reference table;
[0075] Step 4, obtain the target torque T req And by consulting the calibrated lookup tables, the required d-axis current i to be output is obtained. dref and q-axis requested current i qref .
[0076] like Figure 3 As shown, the calibration maximum torque-to-current ratio lookup table includes:
[0077] Step 101, obtain the maximum operating current i of the motor. maxSet the required phase current i based on the maximum operating current. s The step size ensures the phase current i s The number of values taken is greater than the set number, such as 15 or 16.
[0078] Step 102, set the preset phase current i s Input the dynamometer test bench host computer, and the test bench host computer will execute the preset automated program to start the calibration.
[0079] Step 103, input a phase current i s Adjust the current angle θ until the motor output torque begins to decrease, then record the phase current i before the torque begins to decrease. s The current angle θ and motor output torque are calibrated, and the bench output phase current i is then determined. s A table corresponding to the current angle θ.
[0080] Generally, it is recommended to use the first i s =20, the first current angle θ =90.
[0081] The dynamometer begins to collect average data every 5 seconds, then collects data once every 100ms, and takes the average value after 50 collections to calculate the current motor output torque.
[0082] After obtaining the current motor output torque, the program enters a judgment procedure to determine whether the current torque is greater than the torque at the previous moment.
[0083] If the current motor output torque is greater than the motor output torque at the previous moment, it is determined that the motor output torque has not yet started to decrease. At this time, the current angle θ is reduced by the specified current angle adjustment step size, such as 1, and the motor output torque is judged again.
[0084] Repeat the above operation until the current motor output torque is less than the motor output torque at the previous moment;
[0085] If the current motor output torque is less than the motor output torque at the previous moment, it is determined that the motor output torque has started to decrease. At this time, the phase current i at which the torque begins to decrease is recorded. s The current angle θ and the motor output torque. Reasonable allocation of the direct-axis current i. d and cross-axis current i q This causes the motor to operate at the current phase current i s Maximum output torque T max When multiple current angle torques are at their maximum values, the current angle output is taken from the middle value.
[0086] Step 104, input the next phase current i s Repeat the above steps until the final input phase current i is reached. s Greater than or equal to the motor peak current imax .
[0087] Step 105, based on the recorded phase currents i s And the current angle θ, according to the formula Calculate the corresponding direct-axis current i d and cross-axis current i q The curve fitting tool is used to perform curve fitting to obtain the direct-axis current i corresponding to the motor output torque. d A one-dimensional table is used to provide the motor controller software with a lookup table to output the direct-axis current i. d .
[0088] like Figure 4 As shown, the motor flux linkage calibration table includes:
[0089] Step 201, based on the maximum operating current i of the motor max Set a reasonable quadrature axis current i q The step size needs to be consistent with the subsequent inductor calibration adjustment step size.
[0090] Step 202, set the preset quadrature-axis current i q Input the dynamometer test bench host computer, and the test bench host computer will execute the preset automated program to start the calibration.
[0091] Step 203, convert the direct-axis current i d Set it to 0, and input different quadrature-axis currents i in sequence. q Simultaneously, the output torque of the dynamometer is collected. The dynamometer begins to collect an average of 5 seconds of data, with a data acquisition interval of 100ms. After 50 data acquisitions, the average value is taken to calculate the current motor output torque.
[0092] Step 204, record each quadrature-axis current i q and the corresponding motor output torque, up to the final input quadrature-axis current i q Greater than or equal to the motor peak current i max .
[0093] Step 205, recording completes the quadrature-axis current i. q A one-dimensional table corresponding to the motor output torque, based on the recorded quadrature-axis current i q Combining formulas Calculate different quadrature-axis currents i q Corresponding motor flux A one-dimensional table corresponding to the motor output torque and the motor flux linkage is obtained.
[0094] like Figure 5 As shown, the motor inductance calibration table includes:
[0095] Step 301, based on the maximum operating current i of the motor max Set a reasonable quadrature axis current i q and direct-axis current i d The step size, the quadrature-axis current i q The step size needs to be the same as the quadrature-axis current i in step 2. q Keep the step size consistent, direct-axis current i d The maximum value must reach the peak current.
[0096] Step 302: Import the preset current table into the dynamometer test bench, and the test bench will run according to the preset automated program.
[0097] Step 303, input a direct-axis current i d Values are input sequentially using multiple quadrature-axis currents i with a specified quadrature-axis current adjustment step size. q Record the current direct-axis current i d The cross-axis currents i q The corresponding motor output torque, up to the final input quadrature-axis current i q Or the calculated phase current i s Greater than or equal to the motor peak current i max .in,
[0098] Step 304, input the next direct-axis current i d The value is calculated, and the above operation is repeated until the final input direct-axis current i is reached. d Greater than or equal to the motor peak current i max .
[0099] Step 305: The current calibration is complete, and a two-dimensional table of motor output torque corresponding to iq and id is obtained. Based on the recorded direct-axis current i... d Cross-axis current i q Calculate the corresponding motor inductance L dq The calculation formula is:
[0100] like Figure 6 The diagram illustrates the vector control principle of the motor controller software in this scheme. The calculation is based on the target torque T. req The d-axis requested current i can be calculated. dref and q-axis requested current i qref Step 4 includes:
[0101] Step 401, based on the target torque T req Consult the calibration lookup table to obtain the required d-axis current i to be output. dref ;
[0102] Step 402, based on the q-axis feedback current i from the previous moment qcu r queries the calibrated lookup table to obtain the target motor flux linkage.
[0103] Step 403, based on the d-axis feedback current i from the previous moment dcur and the q-axis feedback current i at the previous moment qcur By consulting the calibration reference table, the target motor inductance L can be obtained. dq ;
[0104] Step 404, based on the target torque T req d-axis requested current i qref Target motor flux Target motor inductance L dq Calculate the required q-axis current i to be output. qref , The calculated d-axis requested current i dref and q-axis requested current i qref It is transmitted to the current loop output.
[0105] In one embodiment, the motor temperature is monitored in real time during the calibration process. When the motor temperature exceeds the set first temperature threshold, the current operating condition is unloaded until the motor temperature drops to the set second temperature threshold, at which point the previous operating condition is restored and calibration continues.
[0106] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.
[0107] In the above detailed description, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features of the single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, wherein each claim stands alone as a preferred embodiment of the invention.
[0108] The disclosed embodiments have been described above to enable any person skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the spirit and scope of this disclosure. Therefore, this disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.
[0109] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as it is used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."
[0110] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. A rapid calibration method for permanent magnet synchronous motors in new energy vehicles, characterized in that, Includes the following steps: Table for calibrating the maximum torque-to-current ratio; Motor flux linkage calibration table; Motor inductance calibration table; Obtain the target torque T reg And by consulting the calibrated lookup tables, the required d-axis current i to be output is obtained. dref and q-axis requested current i qref ; The calibration maximum torque-to-current ratio lookup table includes: Input a phase current i s Adjust the current angle θ until the motor output torque begins to decrease, then record the phase current i before the torque begins to decrease. s Current angle θ and motor output torque; Input the next phase current i s And repeat the above operation until the final input phase current i s Greater than or equal to the motor peak current i max ; Based on the recorded phase currents i s Given the current angle θ, calculate the corresponding direct-axis current i. d and cross-axis current i q ; A calibration table for motor flux linkage includes: The direct-axis current i d Set it to 0, and input different quadrature-axis currents i in sequence. q Record the cross-axis currents i q and the corresponding motor output torque, up to the final input quadrature-axis current i q Greater than or equal to the motor peak current i max ; According to the recorded quadrature-axis current i q Calculate different quadrature-axis currents i q Corresponding motor flux A calibration table for motor inductance includes: Input a direct-axis current i d Values are input sequentially using multiple quadrature-axis currents i with a specified quadrature-axis current adjustment step size. q Record the current direct-axis current i d The cross-axis currents i q The corresponding motor output torque, up to the final input quadrature-axis current i q Or the calculated phase current i s Greater than or equal to the motor peak current i max ; Input the next direct-axis current i d The value is calculated, and the above operation is repeated until the final input direct-axis current i is reached. d Greater than or equal to the motor peak current i max ; Based on the recorded direct-axis current i d Cross-axis current i q Calculate the corresponding motor inductance L dq .
2. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, The target torque T is obtained req And by consulting the calibrated lookup tables, the required d-axis current i to be output is obtained. dref and q-axis requested current i qref include: Based on the target torque T req Consult the calibration lookup table to obtain the required d-axis current i to be output. dref ; Based on the q-axis feedback current i at the previous moment qcur By consulting the calibration reference table, the target motor flux linkage can be obtained. Based on the d-axis feedback current i from the previous moment dcur and the q-axis feedback current i at the previous moment qcur By consulting the calibration reference table, the target motor inductance L can be obtained. dq ; Based on the target torque T req d-axis requested current i dref Target motor flux Target motor inductance L dq Calculate the required q-axis current i to be output. qref .
3. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 2, characterized in that, The q-axis requested current i that needs to be output now qref Calculate using the following formula: Among them, P n This represents the number of pole pairs of the motor.
4. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, The method for obtaining the motor output torque includes: The dynamometer continuously samples torque at specified sampling intervals until the specified number of samplings is reached. The average value of multiple collected torque data points is taken as the motor output torque.
5. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, During the calibration of the maximum torque-current ratio lookup table, when a phase current i is input... s After a current angle θ, it also includes: Determine the output torque of the motor; If the current motor output torque is greater than the motor output torque at the previous moment, it is determined that the motor output torque has not yet started to decrease. At this time, the current angle θ is reduced by adjusting the step size of the specified current angle, and the motor output torque is judged again. Repeat the above operation until the current motor output torque is less than the motor output torque at the previous moment; If the current motor output torque is less than the motor output torque at the previous moment, it is determined that the motor output torque has started to decrease. At this time, the phase current i before the torque started to decrease is recorded. s Current angle θ and motor output torque.
6. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, The recorded phase current i s Given the current angle θ, calculate the corresponding direct-axis current i. d and cross-axis current i q include: According to the formula Calculate the corresponding direct-axis current i d and cross-axis current i q ; The direct-axis current i corresponding to different motor output torques was obtained by curve fitting. d and cross-axis current i q .
7. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, The motor magnetic flux Calculate using the following formula: Among them, P n L is the number of pole pairs of the motor. d L is the d-axis inductance of the motor. q T is the q-axis inductance of the motor. e This refers to the output torque of the motor.
8. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, The motor inductance L dq The following formula is used for calculation: Among them, P n L is the number of pole pairs of the motor. d L is the d-axis inductance of the motor. q T is the q-axis inductance of the motor. e This refers to the output torque of the motor.
9. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that, The q-axis requested current i qref The following formula is used for calculation: Among them, P n This represents the number of pole pairs of the motor.
10. The rapid calibration method for permanent magnet synchronous motors in new energy vehicles according to claim 1, characterized in that: During the calibration process, the motor temperature is monitored in real time. When the motor temperature exceeds the set first temperature threshold, the current operating condition is unloaded until the motor temperature drops to the set second temperature threshold, at which point the previous operating condition is restored and calibration continues.