A method, device and medium for detecting the rotor position of a permanent magnet synchronous motor

Abstract

The present application discloses a method, device and computer-readable storage medium for detecting the rotor position of a permanent magnet synchronous motor. This method obtains the position estimate of the motor rotor, the predicted values ​​of the current components on the d-axis and q-axis and the sampled current of the motor, and determines the speed observation error of the motor based on the sampled current, the predicted value and the position estimate, and determines the speed estimate based on the speed observation error. Finally, the speed estimate is integrated to obtain the rotor position estimate. This method does not require the use of a position sensor, increases the reliability of the system, and reduces the installation and repair and maintenance costs. In addition, this method is not affected by the environment, has a small debugging workload, and does not require additional measures to start the motor from a standstill. Moreover, it can achieve high-precision detection of the rotor position in all speed sections, thereby improving the working efficiency of the permanent magnet synchronous motor.

Description

Technical Field

[0001] The present application relates to the field of electromagnetic technology, and in particular to a method and device for detecting the rotor position of a permanent magnet synchronous motor, and a computer-readable storage medium. Background Art

[0002] In permanent magnet synchronous motor drive systems, rotor field-oriented vector control is commonly used, requiring detection of the motor's rotor position and speed. In traditional drive systems, rotor position and speed are typically detected by installing mechanical sensors on the rotor shaft. However, the presence of position sensors not only reduces system reliability but also increases installation and maintenance costs. Currently, methods that do not utilize position sensors mostly employ extended Kalman filtering or model reference adaptive systems. Extended Kalman filtering, as a reliable optimal estimation algorithm, effectively processes random noise and accurately estimates target values. It offers high precision and excellent dynamic performance, enabling speed-sensorless rotor position estimation. Model reference adaptive systems, on the other hand, derive the speed estimation adaptability formula based on stability principles.

[0003] However, since the matrix parameters of the extended Kalman filter are affected by the environment, continuous trial and error are required, and the actual debugging process is labor-intensive. The model adaptation corrects the speed error based on the adaptive rate, and its performance is relatively good at high speeds. However, it is greatly affected by the motor parameters when running at low speeds or when stationary.

[0004] In view of the above technologies, seeking a high-precision detection method with small workload and applicable to the full speed range is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a method, device and computer-readable storage medium for detecting the rotor position of a permanent magnet synchronous motor.

[0006] To solve the above technical problems, the present application provides a method for detecting the rotor position of a permanent magnet synchronous motor, comprising:

[0007] Obtaining a current position estimate of the motor rotor, wherein the current position estimate is 0 when the motor is started;

[0008] Obtain predicted values ​​of the current components on the d-axis and q-axis;

[0009] Obtaining a sampled current of the motor, and determining a speed observation error of the motor according to the sampled current, the predicted value, and the current position estimate;

[0010] determining a speed estimation value based on the speed observation error;

[0011] The estimated value of the rotational speed is integrated to obtain an estimated value of the current position of the rotor.

[0012] Preferably, after determining the speed estimation value according to the speed observation error, the method further includes:

[0013] The speed estimation value is filtered to obtain a speed estimation filtered value of the motor, and the step of obtaining predicted values ​​of the current components on the d-axis and the q-axis is entered.

[0014] Preferably, obtaining predicted values ​​of components of the current on the d-axis and the q-axis includes:

[0015] Obtaining the generated voltage, the resistance, inductance and motor flux parameters of the motor;

[0016] The predicted value is determined according to the sampled current, the position estimation value, the speed estimation filter value, the generated voltage, the resistance, the inductance and the motor flux parameter.

[0017] Preferably, determining the speed observation error of the motor includes:

[0018] Obtaining a projection value of the sampled current at the position estimation value;

[0019] Determining the current prediction error, where the current prediction error is obtained by subtracting the predicted value from the projection value;

[0020] The speed observation error is determined according to the current prediction error and the speed estimation filter value using a fourth-order speed observation equation of a permanent magnet synchronous motor.

[0021] Preferably, determining the speed estimation value according to the speed observation error includes:

[0022] Determining the ratio of the wave voltage to the motor flux parameter;

[0023] Design PI correction process;

[0024] The speed observation error is used as the input of the PI correction link;

[0025] The ratio is added to the output value of the PI correction link to determine the speed estimation value.

[0026] Preferably, filtering the speed estimation value to obtain a filtered speed estimation value of the motor includes:

[0027] The speed estimation value is filtered by low-pass filtering to obtain a speed estimation filtered value of the motor.

[0028] In order to solve the above technical problems, the present application also provides a permanent magnet synchronous motor rotor position detection device, comprising:

[0029] A first acquisition module is used to obtain a current position estimate value of the motor rotor, wherein the current position estimate value is 0 when the motor is started;

[0030] A second acquisition module is used to obtain predicted values ​​of components of the current on the d-axis and the q-axis;

[0031] a first determining module, configured to obtain a sampled current of the motor, and determine a speed observation error of the motor according to the sampled current, the predicted value, and the position estimation value;

[0032] a second determining module, configured to determine a speed estimation value according to the speed observation error;

[0033] An integration module is used to integrate the rotational speed estimation value to obtain a current position estimation value of the rotor.

[0034] To solve the above technical problems, the present application further provides a device for detecting the rotor position of a permanent magnet synchronous motor, comprising:

[0035] memory for storing computer programs;

[0036] The processor is configured to implement the steps of the method for detecting the rotor position of a permanent magnet synchronous motor as described above when executing the computer program.

[0037] To solve the above technical problems, the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for detecting the rotor position of a permanent magnet synchronous motor as described above are implemented.

[0038] In order to solve the above technical problems, the present application also provides a permanent magnet synchronous motor, comprising a motor and also comprising: a device for detecting the rotor position of the permanent magnet synchronous motor.

[0039] The present application provides a method for detecting the rotor position of a permanent magnet synchronous motor. This method obtains the position estimate of the motor rotor, the predicted values ​​of the current components on the d-axis and q-axis, and the sampled current of the motor, and determines the speed observation error of the motor based on the sampled current, predicted value, and position estimate, and determines the speed estimate based on the speed observation error. Finally, the speed estimate is integrated to obtain the rotor position estimate. This method does not require the use of a position sensor, increases the reliability of the system, and reduces installation and repair and maintenance costs. In addition, this method is not affected by the environment, has a small debugging workload, and does not require additional measures to enable the motor to start running from a standstill. Moreover, it can achieve high-precision detection of the rotor position in all speed sections, thereby improving the working efficiency of the permanent magnet synchronous motor.

[0040] On this basis, the present application also provides a permanent magnet synchronous motor rotor position detection device and a computer-readable storage medium, with the same effects as above. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 A process of a method for detecting the position of a permanent magnet synchronous motor provided in an embodiment of the present application;

[0043] Figure 2 A flowchart of another method for detecting the position of a permanent magnet synchronous motor provided in an embodiment of the present application;

[0044] Figure 3 A waveform diagram of the speed of the motor provided in an embodiment of the present application when it is started from 0 speed;

[0045] Figure 4 A waveform diagram of the position angle when the motor provided in the embodiment of the present application is started from 0 speed;

[0046] Figure 5 A waveform diagram of the position angle of the motor at rated speed provided in an embodiment of the present application;

[0047] Figure 6 A waveform diagram of the speed of the motor provided in an embodiment of the present application at rated speed;

[0048] Figure 7 A structural diagram of a permanent magnet synchronous motor position detection device provided in an embodiment of the present application;

[0049] Figure 8This is a structural diagram of a permanent magnet synchronous motor position detection device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0050] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0051] The core of this application is to provide a method for detecting the position of a permanent magnet synchronous motor.

[0052] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0053] Figure 1 A flow chart of a method for detecting the position of a permanent magnet synchronous motor provided in an embodiment of the present application is shown in the figure. The method for detecting the position of a permanent magnet synchronous motor includes:

[0054] S10: Obtain the current estimated position of the motor rotor.

[0055] S11: Obtain predicted values ​​of the current components on the d-axis and q-axis.

[0056] S12: Obtain the sampled current of the motor, and determine the speed observation error of the motor based on the sampled current, the predicted value, and the current position estimation value.

[0057] S13: Determine a speed estimation value based on the speed observation error.

[0058] S14: Integrate the estimated speed value to obtain the estimated current position value of the rotor.

[0059] Understandably, permanent magnet synchronous motor drive systems typically employ rotor field-oriented vector control, requiring detection of the motor's rotor position and speed. In traditional drive systems, rotor position and speed are typically detected using mechanical sensors mounted on the rotor shaft. However, the presence of position sensors not only reduces system reliability but also increases installation and maintenance costs. Currently, approaches that avoid position sensors mostly employ extended Kalman filtering or model reference adaptive systems. Extended Kalman filtering, as a reliable optimal estimation algorithm, effectively handles random noise and accurately estimates target values, offering high precision and excellent dynamic performance, enabling speed sensorless rotor position estimation. Model reference adaptive systems, on the other hand, derive a speed estimation adaptive rate formula based on stability principles. However, because the matrix parameters of the extended Kalman filter are affected by the environment, continuous trial and error are required, making the actual debugging process labor-intensive. Model adaptive systems, which correct speed errors based on the adaptive rate, perform well at high speeds, but are significantly affected by motor parameters at low speeds or when stationary. Therefore, the present application proposes a method for detecting the position of a permanent magnet synchronous motor. For step S10, the current position estimate of the motor rotor is obtained, that is, the position estimate of the rotor at the current moment is obtained. It can be understood that when the motor is just started, the current position estimate of the motor rotor is 0.

[0060] Regarding step S12, the motor's sampled current is obtained, and the motor's speed observation error is determined based on the sampled current, the predicted value, and the current position estimate. The motor's speed observation error is the error in the speed deviation from the actual speed. There is no limitation on how to determine the motor's speed observation error, and the motor's speed observation error can be determined based on specific implementation circumstances. As described in step S13, the speed estimate is determined based on the speed observation error. In other words, the speed estimate can be calculated based on the deviation error.

[0061] Furthermore, the current position estimate obtained by integrating the estimated speed value in step S14 is not the same as the current position estimate in step S10. Specifically, the current position estimate in step S10 is the current position estimate at time T0, while the current position estimate in step S14 is the current position estimate at time T1. Furthermore, after obtaining the current position estimate at time T1, the process returns to step S10 and performs a closed-loop cycle. This allows closed-loop observation of the rotor position, meaning that the current position estimate is initially 0, and only after a closed-loop cycle does the current position estimate have a value.

[0062] This embodiment provides a method for detecting the rotor position of a permanent magnet synchronous motor. This method obtains the position estimate of the motor rotor, the predicted values ​​of the current components on the d-axis and q-axis, and the sampled current of the motor, and determines the speed observation error of the motor based on the sampled current, predicted value, and position estimate, and determines the speed estimate based on the speed observation error. Finally, the speed estimate is integrated to obtain the rotor position estimate. This method does not require the use of a position sensor, increases the reliability of the system, and reduces installation and maintenance costs. In addition, this method is not affected by the environment, has a small debugging workload, and does not require additional measures to enable the motor to start running from a standstill. Furthermore, high-precision detection of the rotor position in all speed sections can be achieved, thereby improving the working efficiency of the permanent magnet synchronous motor.

[0063] Based on the above embodiments, Figure 2 A flow chart of another method for detecting the position of a permanent magnet synchronous motor provided in an embodiment of the present application is shown in FIG. Figure 2 As shown, after determining the speed estimation value according to the speed observation error, the following steps are further included:

[0064] S15: Filtering the speed estimation value to obtain a speed estimation filtered value of the motor.

[0065] It is worth noting that filtering the speed estimate and integrating the speed estimate are two parallel steps, and the speed estimate filter value will be used as one of the parameters for obtaining the predicted values ​​of the current components on the d-axis and q-axis in the next round. That is to say, in the first round, the speed estimate filter value and the current position estimate of the rotor are both 0.

[0066] The present embodiment provides a method for filtering the estimated speed value to obtain a filtered estimated speed value of the motor, which is used as one of the parameters for current prediction. The real-time value of the estimated speed is not used, which can avoid high-frequency fluctuations in the observed speed and position that affect the control performance. The actual speed of the motor can also be accurately obtained, thereby improving the working efficiency of the motor.

[0067] Based on the above embodiment, how to obtain the predicted values ​​of the current components on the d-axis and the q-axis is defined, wherein obtaining the predicted values ​​includes:

[0068] Get the wave voltage u d and u q , the motor's inductance L d and L q , resistor R s and motor flux parameter Ψ f .

[0069] And according to the sampling current, position estimation value, speed estimation filter value, the wave voltage u d and u q 、Inductor Ld and L q , resistor R s and motor flux parameter Ψ f Determine the predicted value.

[0070] There are no restrictions on how to obtain the sampled current, generated voltage, motor inductance, resistance, and flux parameters. The predicted values ​​of the current components on the d-axis and q-axis are determined by using the projection values ​​id and iq of the sampled current at the estimated position and the discretized equations of the motor stator current. The sampled three-phase current is transformed by CLACK and PARK to obtain the current components id and iq on the d-axis and q-axis in the rotating coordinate system. The CLACK and PARK transformations are as follows:

[0071] i α =i a ,

[0072] i d =i α *cos(θ est )+i β *sin(θ est )i q =i β *cos(θ est )-i α *sin(θ est )

[0073] Then, the speed estimation filter value is used to predict the current components on the d-axis and q-axis i dest and i qest To determine, the formula is as follows:

[0074]

[0075]

[0076] Then, the general form of the fourth-order Runge-Kutta method is applied to obtain the discrete equation of the motor stator current, from which the predicted values ​​of the current components on the d-axis and q-axis are obtained, as follows:

[0077]

[0078]

[0079] Where h is the current sampling period, and the slope formulas for each order are as follows:

[0080] The first-order slope is:

[0081]

[0082]

[0083] The second-order slope is:

[0084]

[0085]

[0086] The third-order slope is:

[0087]

[0088]

[0089] The fourth-order slope is:

[0090]

[0091]

[0092] It is worth noting that the calculation formula provided in this embodiment is only a preferred implementation method. The calculation formula can be selected according to the specific implementation situation and will not be described in detail in this embodiment.

[0093] The present embodiment provides a method for obtaining the predicted values ​​of the components of the current on the d-axis and the q-axis by obtaining the wave voltage u d and u q , the motor's inductance L d and L q , resistor R s and motor flux parameter Ψ f And according to the current sampling value, position estimation value, speed estimation filter value, the wave voltage u d and u q 、Inductor L d and L q , resistor R s and motor flux parameter Ψ f Determine the predicted value. This method accurately calculates the predicted value of the current and is relatively simple to implement with little workload, thus effectively reducing the workload of the motor and increasing the service life of the motor.

[0094] Based on the above embodiment, how to determine the speed observation error of the motor is defined, wherein determining the speed observation error of the motor includes the following steps:

[0095] The projection value of the sampled current under the estimated position value is obtained to determine the current prediction error. The current prediction error is obtained by subtracting the current prediction value from the projection value of the sampled current under the estimated position value. The speed observation error is determined based on the current prediction error, the speed estimation filter value and the fourth-order speed observation equation of the permanent magnet synchronous motor.

[0096] Among them, the projection value i of the sampled current under the position estimation value is d 、i q , the sampling current is i a and i b The current prediction error is obtained by subtracting the current prediction value from the projection value. The expression of the fourth-order speed observer equation of the permanent magnet synchronous motor is as follows:

[0097] w rest (k) = w rest (k-1)+K1(i d -i dest )+K2(i a -i qest )

[0098] Among them, w rest (k-1) is the estimated speed at the previous moment, w rest (k) is the estimated value of the speed at the current moment, K1 and K2 are the speed state observation error calculation parameters. Moreover, this equation is the most important equation in the fourth-order state equation. This embodiment uses this equation to calculate the speed estimation error w resterr Perform calculations.

[0099] w resterr =w rest (k)-w rest (k-1)=K1(i d -i dest )+K2(i q -i qest )

[0100] In addition, the formula provided in this embodiment is only a preferred implementation method, and the formula can be selected according to the specific implementation situation. This embodiment will not elaborate on other formulas.

[0101] The method for determining the motor speed observation error provided in this embodiment determines the current prediction error by obtaining the projection value of the sampled current under the estimated position value. The current prediction error is obtained by subtracting the current prediction value from the projection value of the sampled current under the estimated position value. The speed observation error is then determined using a fourth-order speed observation equation based on the current prediction error and the speed estimation filter value. Furthermore, in practical applications, only the speed state observation error calculation parameters K1 and K2 need to be appropriately adjusted. This reduces the computational complexity of the software, making it relatively easy to implement in engineering, thereby improving the operating efficiency of the motor.

[0102] On the basis of the above embodiment, how to determine the speed estimation value is limited. The speed estimation value is determined according to the speed observation error by first determining the ratio of the wave voltage to the motor flux parameter, adding the ratio to the observation error, and thus obtaining the speed estimation value.

[0103] It can be understood that the ratio of the wave voltage to the motor flux parameter is used as a compensation amount to compensate for the speed observation error, which can improve the speed observation speed.

[0104] By designing a software algorithm and a PI correction step, the observed speed error is compared with zero and then fed into the PI correction step. After correction by the PI correction step, the observed speed error is stabilized near zero, meaning that the observed speed is close to the actual speed, ensuring the accuracy of the speed estimate. This method superimposes the compensation value and the PI controller output to form the observed speed value. The algorithm is simple, and in practical applications, only the appropriate PI controller parameters need to be selected. This method enables rapid speed tracking and error-free observation, ensuring the accuracy of rotor position detection.

[0105] In addition, the speed estimation value is filtered to obtain the motor speed estimation filter value through low-pass filtering. The low-pass filtering process can weaken the high-frequency component, so that the high-frequency fluctuation in the current estimation value is smaller, and thus the high-frequency fluctuation in the speed estimation is also smaller, and finally a good current and speed closed-loop control function can be obtained.

[0106] It can be seen that the method for determining the speed estimation value and the manner of filtering the speed estimation value provided in this embodiment effectively improve the accuracy of the speed and easily obtain good current and speed closed-loop control functions.

[0107] In addition, this application also provides the position angle waveform and speed waveform of the motor during the process of starting from 0 speed to 10HZ. Figure 3 The waveform diagram of the motor speed when it starts from 0 speed provided in the embodiment of the present application is as follows: Figure 4 This is a waveform diagram of the position angle when the motor provided in the embodiment of the present application is started from 0 speed.

[0108] As shown in the figure, there are two waveforms in each figure. Figure 3 The two waveforms in the figure are the true value and the observed value of the speed read by the encoder. It can be seen that the observed value can quickly track the actual value, and the two waveforms almost overlap, and the speed fluctuation is small, which proves that the dynamics of the speed observation during the low-speed startup of the motor in this application is good and the steady-state error is very small. Figure 4 The two waveforms represent the true value and the observed value of the position angle read by the encoder, respectively. As shown in the figure, the observed value can quickly track the actual value, and the two waveforms almost overlap, which also proves that during the process of the motor starting from a standstill, the observation dynamics is good and the observation error is very small.

[0109] and Figure 5 and Figure 6They are respectively the waveform diagram of the position angle and the waveform diagram of the speed of the motor provided in the embodiment of the present application at the rated speed. As shown in the figure, the motor is also in a very stable state when working at high speed, and this embodiment will not be repeated.

[0110] It can be seen that the embodiments of the present application, by drawing the waveforms of the motor starting from static to low-speed operation and high-speed operation, it is concluded that the motor can start from static to low-speed operation and high-speed operation without adding other measures and with less workload, thereby achieving high-precision detection of the rotor position in all speed sections and improving the working efficiency of the permanent magnet synchronous motor. In the above embodiments, the detection method of the permanent magnet synchronous motor position is described in detail, and the present application also provides a corresponding embodiment of the detection device for the permanent magnet synchronous motor position. It should be noted that the present application describes the embodiments of the device part from two perspectives, one is based on the perspective of the functional module, and the other is based on the perspective of hardware.

[0111] Figure 7 A structural diagram of a permanent magnet synchronous motor position detection device provided in an embodiment of the present application, such as Figure 7 As shown, the detection device for the position of the permanent magnet synchronous motor includes:

[0112] A first acquisition module 10 is used to obtain a current position estimate of the motor rotor, wherein the current position estimate is 0 when the motor starts;

[0113] A second acquisition module 11 is used to obtain predicted values ​​of the current components on the d-axis and the q-axis;

[0114] A first determination module 12 is configured to obtain a sampled current of the motor and determine a speed observation error of the motor based on the sampled current, the predicted value, and the position estimation value;

[0115] A second determination module 13 is configured to determine a speed estimation value based on a speed observation error;

[0116] The integration module 14 is configured to integrate the estimated speed value to obtain an estimated value of the current position of the rotor.

[0117] Figure 8 This is a structural diagram of a permanent magnet synchronous motor position detection device provided in another embodiment of the present application, as shown in FIG. Figure 8 As shown, the detection device for the position of the permanent magnet synchronous motor includes: a memory 20 for storing a computer program;

[0118] The processor 21 is configured to implement the steps of the method for detecting the position of the permanent magnet synchronous motor mentioned in the above embodiment when executing the computer program.

[0119] The permanent magnet synchronous motor position detection device provided in this embodiment may include but is not limited to a smart phone, a tablet computer, a laptop computer, or a desktop computer.

[0120] Among them, the processor 21 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 21 can be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 21 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 21 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 21 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0121] The memory 20 may include one or more computer-readable storage media, which may be non-transitory. The memory 20 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In this embodiment, the memory 20 is at least used to store the following computer program 201, wherein, after the computer program is loaded and executed by the processor 21, it can implement the relevant steps of the method for detecting the position of the permanent magnet synchronous motor disclosed in any of the aforementioned embodiments. In addition, the resources stored in the memory 20 may also include an operating system 202 and data 203, etc., and the storage method may be temporary storage or permanent storage. Among them, the operating system 202 may include Windows, Unix, Linux, etc. The data 203 may include but is not limited to data of the method for detecting the position of the permanent magnet synchronous motor, etc.

[0122] In some embodiments, the device for detecting the position of a permanent magnet synchronous motor may further include a display screen 22 , an input / output interface 23 , a communication interface 24 , a power supply 25 , and a communication bus 26 .

[0123] Those skilled in the art will understand that Figure 8The structure shown in the figure does not constitute a limitation on the device for detecting the position of a permanent magnet synchronous motor, and may include more or fewer components than those shown in the figure.

[0124] Finally, the present application also provides an embodiment corresponding to a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps described in the above method embodiment.

[0125] It is understandable that if the method in the above embodiment is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and executes all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0126] The above is a detailed introduction to the method, device and computer-readable storage medium for detecting the position of a permanent magnet synchronous motor provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0127] It should also be noted that, in this specification, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

Claims

1. A method for detecting the rotor position of a permanent magnet synchronous motor, characterized in that: include: Obtaining a current position estimate of the motor rotor, wherein the current position estimate is 0 when the motor is started; Obtain predicted values ​​of the current components on the d-axis and q-axis; Obtaining a sampled current of the motor, and determining a speed observation error of the motor according to the sampled current, the predicted value, and the current position estimate; determining a speed estimation value based on the speed observation error; Integrating the estimated speed value to obtain an estimated current position value of the rotor; Wherein, determining the speed observation error of the motor includes: Obtaining a projection value of the sampled current at the position estimation value; determining a current prediction error, where the current prediction error is obtained by subtracting the predicted value from the projected value; The speed observation error is determined according to the current prediction error and the speed estimation filter value using the fourth-order speed observation equation of the permanent magnet synchronous motor; the speed estimation filter value is a value obtained by filtering the speed estimation value.

2. The method for detecting the rotor position of a permanent magnet synchronous motor according to claim 1, wherein: After determining the speed estimation value according to the speed observation error, the method further includes: The speed estimation value is filtered to obtain a speed estimation filtered value of the motor, and the step of obtaining predicted values ​​of the current components on the d-axis and the q-axis is entered.

3. The method for detecting the rotor position of a permanent magnet synchronous motor according to claim 2, wherein: The step of obtaining predicted values ​​of components of the current on the d-axis and the q-axis includes: Obtaining the generated voltage, the resistance, inductance and motor flux parameters of the motor; The predicted value is determined according to the sampled current, the position estimation value, the speed estimation filter value, the generated voltage, the resistance, the inductance and the motor flux parameter.

4. The method for detecting the rotor position of a permanent magnet synchronous motor according to claim 3, wherein: Determining the speed estimation value according to the speed observation error includes: Determining the ratio of the wave voltage to the motor flux parameter; Design PI correction process; The speed observation error is used as the input of the PI correction link; The ratio is added to the output value of the PI correction link to determine the speed estimation value.

5. The method for detecting the rotor position of a permanent magnet synchronous motor according to claim 2, wherein: The filtering of the speed estimation value to obtain the speed estimation filtered value of the motor includes: The speed estimation value is filtered by low-pass filtering to obtain a speed estimation filtered value of the motor.

6. A device for detecting the rotor position of a permanent magnet synchronous motor, characterized in that: include: A first acquisition module is used to obtain a current position estimate value of the motor rotor, wherein the current position estimate value is 0 when the motor is started; A second acquisition module is used to obtain predicted values ​​of components of the current on the d-axis and the q-axis; a first determining module, configured to obtain a sampled current of the motor, and determine a speed observation error of the motor according to the sampled current, the predicted value, and the position estimation value; a second determining module, configured to determine a speed estimation value according to the speed observation error; an integration module, configured to integrate the estimated speed value to obtain an estimated current position value of the rotor; Wherein, the first determining module is used to: obtain a projection value of the sampled current under the position estimation value; determining a current prediction error, where the current prediction error is obtained by subtracting the predicted value from the projected value; The speed observation error is determined according to the current prediction error and the speed estimation filter value using the fourth-order speed observation equation of the permanent magnet synchronous motor; the speed estimation filter value is a value obtained by filtering the speed estimation value.

7. A device for detecting the rotor position of a permanent magnet synchronous motor, characterized in that: include: memory for storing computer programs; A processor is configured to implement the steps of the method for detecting the rotor position of a permanent magnet synchronous motor according to any one of claims 1 to 5 when executing the computer program.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for detecting the rotor position of a permanent magnet synchronous motor according to any one of claims 1 to 5 are implemented.

9. A permanent magnet synchronous motor, comprising a motor, characterized in that: Also includes: A device for detecting the rotor position of a permanent magnet synchronous motor as described in claim 7.

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