Permanent magnet synchronous motor rotor position detection method and device, electronic equipment and storage medium

Abstract

The application discloses a permanent magnet synchronous motor rotor position detection method and device, electronic equipment and a storage medium. When the closed-loop control motor rotates, the rotor position detected by high-frequency injection when the motor is static is first acquired, then the motor starts to rotate, the rotor angle detected after the motor rotates for a certain angle is stored, then the angle difference is used to verify whether the rotor polarity judgment is correct, if correct, it indicates that the motor rotates along a given direction, if incorrect, it indicates that the motor rotates in the wrong direction, at this time, 180 degrees is added to the current detected rotor position, and the motor resumes normal direction rotation, so that the motor can be correctly started.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet synchronous motor technology, specifically to a method, device, electronic equipment, and storage medium for detecting the rotor position of a permanent magnet synchronous motor. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) have advantages such as simple structure, high reliability, no need for excitation current, and improved motor efficiency and power density. They are widely used in many electronic devices, such as automotive motors, washing machines, and electric vehicles.

[0003] In PMSM control, to ensure maximum torque output throughout the entire control cycle, FOC (Field-Oriented Control) is commonly employed. During FOC control, real-time rotor position monitoring is required. Common position detection methods are generally divided into sensor-based and sensorless position detection. Sensor-based detection typically includes Hall effect sensor detection and encoder detection; sensorless detection includes sliding mode detection, Luneburger detection, and high-frequency injection detection. Sliding mode detection and Luneburger detection are suitable for high speeds, while high-frequency injection detection is suitable for low-speed and stationary position detection, and is frequently used during motor startup.

[0004] Current high-frequency injection detection algorithms involve rotor polarity determination during motor rotation control. This determination primarily relies on the saturated convexity effect to determine whether the detected rotor position matches the actual rotor position.

[0005] However, in actual operation, for some motors with weak saturated salient polarity effect, if the polarity is judged by the saturated salient polarity effect, the polarity may be misjudged, which will cause the motor to reverse and become out of control.

[0006] Therefore, solutions to existing technological problems are needed. Summary of the Invention

[0007] The purpose of this invention is to provide a method, device, electronic device, and storage medium for detecting the rotor position of a permanent magnet synchronous motor, so as to ensure that the motor starts correctly and runs smoothly.

[0008] According to a first aspect of the present invention, an embodiment of the present invention provides a method for detecting the rotor position of a permanent magnet synchronous motor, comprising: injecting a high-frequency pulsating voltage into the observation axis system of the permanent magnet synchronous motor, and detecting the rotor position of the permanent magnet synchronous motor when it is stationary after the high-frequency pulsating voltage is injected; when the permanent magnet synchronous motor rotates, acquiring the rotor angle of the motor rotor; and calculating the angle difference between the stationary rotor position and the rotor angle, and determining the actual direction of rotation of the permanent magnet synchronous motor and the actual position of the motor rotor based on the angle difference.

[0009] Optionally, injecting a high-frequency pulsating voltage into the observation shaft system of the permanent magnet synchronous motor and detecting the rotor position of the permanent magnet synchronous motor when it is stationary after the injection of the high-frequency pulsating voltage includes: injecting a high-frequency pulsating voltage into the observation shaft system of the permanent magnet synchronous motor to obtain a response current; extracting the response current to obtain a corresponding high-frequency response current; modulating the high-frequency response current and performing filtering and proportional-integral operations to obtain the rotor speed; and obtaining the corresponding rotor position through subsequent integration operations.

[0010] Optionally, the step of calculating the angle difference between the rotor position and the rotor angle when stationary, and determining the actual direction of rotation of the permanent magnet synchronous motor based on the angle difference, includes: calculating the angle difference between the rotor position and the rotor angle when stationary; determining, based on the angle difference and preset first angle range conditions and second angle range conditions, that the angle difference preferentially satisfies the first angle range conditions or the second angle range conditions; and determining the actual direction of rotation of the permanent magnet synchronous motor according to the determination result.

[0011] Optionally, the first angle range condition is α < Δθ < β or α - 360° < Δθ < β - 360°, and the second angle range condition is -β < Δθ < -α or 360° - β < Δθ < 360° - α, where Δθ represents the angle difference, and α and β represent the threshold values ​​of the angle difference.

[0012] Furthermore, the first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°; the second angle range condition is -60° < Δθ < -30° or 300° < Δθ < 330°.

[0013] Optionally, after determining the actual direction of rotation of the permanent magnet synchronous motor based on the judgment result, the method includes: determining whether the given direction and the actual direction are the same based on the given direction of the permanent magnet synchronous motor and the determined actual direction; when it is determined that the given direction and the actual direction are the same, determining the actual position of the motor rotor; when it is determined that the given direction and the actual direction are different, correcting the currently detected rotor position and determining the actual position of the motor rotor.

[0014] Optionally, the method further includes: after determining the actual position of the motor rotor, controlling the permanent magnet synchronous motor to rotate according to a given direction and a given speed in a closed loop.

[0015] According to a second aspect of the present invention, an embodiment of the present invention provides a rotor position detection device for a permanent magnet synchronous motor, comprising: a rotor position detection module, configured to inject a high-frequency pulse voltage into the observation axis system of the permanent magnet synchronous motor and detect the rotor position of the permanent magnet synchronous motor when stationary after the injection of the high-frequency pulse voltage; a rotor angle acquisition module, configured to acquire the rotor angle of the motor rotor after the permanent magnet synchronous motor rotates; and an actual position determination module, configured to calculate the angle difference between the stationary rotor position and the rotor angle, and determine the actual direction of rotation of the permanent magnet synchronous motor and the actual position of the motor rotor based on the angle difference.

[0016] According to a third aspect of the present invention, an electronic device is provided, comprising a controller and a memory, the memory storing one or more programs configured to be executed by the controller using the permanent magnet synchronous motor rotor position detection method according to any embodiment of the present invention.

[0017] According to a fourth aspect of the present invention, an embodiment of the present invention provides a computer-readable storage medium storing computer software instructions, the computer software instructions being configured to be executed by the controller using the permanent magnet synchronous motor rotor position detection method according to any embodiment of the present invention.

[0018] This invention provides a method, device, electronic device, and storage medium for detecting the rotor position of a permanent magnet synchronous motor, aiming to address the deficiencies in existing technologies. By controlling the motor's rotation in a closed-loop manner, the rotor position θ1 detected by high-frequency injection when the motor is stationary is first acquired. Then, as the motor begins to rotate, the rotor angle θ2 detected after a certain rotation angle is stored. Next, the rotor polarity is verified using the angle difference Δθ = θ2 - θ1. If correct, the motor rotates in the given direction; if incorrect, the rotation direction is wrong. In this case, 180° is added to the currently detected rotor position for correction, and the motor resumes normal rotation, thus ensuring correct motor startup. The proposed secondary polarity judgment algorithm, applicable to high-frequency injection, fills the gaps in existing technologies and effectively avoids the problem of motors not rotating in the given direction, which may be caused by existing high-frequency injection algorithms, thereby ensuring normal motor operation. Furthermore, the detection method used in this invention is simple and efficient, and can be widely applied. Attached Figure Description

[0019] The technical solution and other beneficial effects of the present invention will become apparent from the following detailed description of specific embodiments of the invention, in conjunction with the accompanying drawings.

[0020] Figure 1 This is a schematic diagram of a magnetic orientation vector control.

[0021] Figure 2 This is a schematic diagram of an electronic device according to the present invention.

[0022] Figure 3 This is a flowchart illustrating the steps of a permanent magnet synchronous motor rotor position detection method according to the present invention.

[0023] Figure 4 This is a flowchart of the sub-steps of step S100.

[0024] Figure 5 This is a flowchart of the sub-steps of step S300.

[0025] Figure 6 This is a schematic diagram of the rotor angle detected in the first case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0026] Figure 7 This is a schematic diagram of the rotor angle detected in the second case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0027] Figure 8 This is a schematic diagram of the rotor angle detected in the third case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0028] Figure 9 This is a schematic diagram of the rotor angle detected in the fourth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0029] Figure 10 This is a schematic diagram of the rotor angle detected in the fifth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0030] Figure 11 This is a schematic diagram of the rotor angle detected in the sixth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0031] Figure 12 This is a schematic diagram of the rotor angle detected in the seventh case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0032] Figure 13 This is a schematic diagram of the rotor angle detected in the eighth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented.

[0033] Figure 14 This is a block diagram of a permanent magnet synchronous motor rotor position detection device provided in an embodiment of the present invention. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0035] The terms "first" and "second" used herein are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "multiple" means two or more, unless otherwise explicitly specified.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] The following disclosure provides many different embodiments or examples for implementing different structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0038] This invention provides a method, apparatus, electronic device, and computer-readable storage medium for detecting the rotor position of a permanent magnet synchronous motor. Examples are given below to illustrate the invention; these descriptions are intended to enable those skilled in the art to understand the invention but are not intended to limit the invention.

[0039] In one aspect, embodiments of the present invention provide an electronic device that can be used to execute a permanent magnet synchronous motor rotor position detection method, for providing a permanent magnet synchronous motor solution for correct startup and smooth operation, such as a hardware and software collaborative solution.

[0040] In the process of controlling a permanent magnet synchronous motor via electronic equipment, FOC control is used to achieve maximum torque output. The control principle of FOC is as follows: Figure 1 As shown. Rotational speed reference n ref The difference between the rotor speed n and the speed loop PID controller is calculated and input to the speed loop PID controller. The output i of the speed loop PID controller is... qref As the q-axis current loop reference, when field weakening control is not performed, the d-axis current loop reference i dref The current is 0, and the dq-axis current reference is i. qref i dref With feedback current i q i d The difference is adjusted by PID control and the output V is then used. d V q Then, after inverse Park transform and SVPWM (space vector modulation, or SVM), the three-phase voltage V is obtained. a V b V c The motor rotates. In FOC control, the three-phase current i is collected. a i b i c The feedback current i is obtained after Clark transformation and Park transformation. q i d The rotor position θ needs to be detected during FOC control to participate in PARK and inverse PARK transformations. Therefore, rotor position detection is crucial in FOC control. This can be achieved by employing a high-frequency injection position detection algorithm.

[0041] Furthermore, the process of using a high-frequency injection position detection algorithm to control the motor rotation includes the following steps: stationary rotor position detection, rotor polarity determination, and closed-loop control of motor rotation.

[0042] In one embodiment, such as Figure 2As shown, the electronic device 1000 may include a controller 2000 and a memory 3000. The memory 3000 may be, for example, various non-volatile memories, but not limited thereto, or other storage hardware or its derivatives, used to store programs, parameters, or data, etc. The controller 2000 may be a microcontroller unit (MCU) or an application-specific integrated circuit (ASIC) containing its functions, but not limited thereto, or other signal processing hardware or its derivatives, used to control and drive the permanent magnet synchronous motor (PMSM) 4000. For example, the controller 2000 is electrically connected to the memory 3000. The controller 2000 and the memory 3000 may be separate from each other or integrated. The memory 3000 stores one or more programs, which are configured to be executed by the controller 2000 using the aforementioned permanent magnet synchronous motor rotor position detection method.

[0043] Furthermore, such as Figure 2 As shown, the controller 2000 can be configured as a software module, a hardware module, a software-hardware co-processing module, or other corresponding modules with its functions to drive the permanent magnet synchronous motor 4000. For example, it can start the permanent magnet synchronous motor based on vector control, also known as field-oriented control (FOC), which can control a three-phase AC motor, such as the permanent magnet synchronous motor 4000, by controlling the amplitude and frequency of the output voltage of a frequency converter (not shown in the figure).

[0044] like Figure 2 As shown, many functional modules other than the permanent magnet synchronous motor 4000 can be configured as part of the controller 2000. In the field-oriented control architecture, the control of motor speed and position is mainly achieved by controlling the motor operating current. This typically includes a current loop for current control and a speed loop for speed control, but is not limited to these.

[0045] Specifically, such as Figure 2 As shown, the controller 2000 can be configured to perform functions such as difference calculation, proportional-integral (PI) or proportional-integral-derivative (PID) control, Park inverse transform, Clarke inverse transform, inverter bridge, Clarke transform, Park transform, and position and speed estimation in a coordinated manner. This is used to control the permanent magnet synchronous motor 2000 to start in an open-loop manner, and after verifying the polarity judgment, to drive the permanent magnet synchronous motor 4000 in a closed-loop manner.

[0046] It should be understood that the various functions performed by the numerous functional modules in the controller 2000, such as proportional, integral, differential, difference calculation, transformation, estimation, etc., are not limited to these. The required parameters may be from the output results of other modules or from the output results of different observers (such as ammeters and voltmeters). Their specific features (such as architecture or algorithms) should be understood by those skilled in the art and will not be described in detail here.

[0047] In one embodiment, such as Figure 2 As shown, in the controller 2000, the reference current i of the observed shaft system is... qref The q-axis current i from the Park transform module U5 and after low-pass filtering (LPF) q After performing differential calculations, proportional-integral-derivative (PID) control is then applied to generate voltage V. q , representing the voltage along the q-axis in the (d,q) coordinate system.

[0048] Accordingly, such as Figure 2 As shown, the reference current i supplied to the d-axis dref It can be given as 0, and is related to the d-axis current i from the Park transformation module U5 after low-pass filtering (LPF). d After performing differential calculation, a proportional-integral (PID) calculation is performed to generate the voltage V. d , used to represent the voltage along the d-axis in the (d,q) coordinate system. Thus, the voltage V q V d It can be used in the Park inverse transform module U1 to generate voltage V based on the Park inverse transform. α V β , representing the voltage along the α and β axes in the (α,β) coordinate system; the voltage V α V β The Space Vector Modulation (SVPWM) module U2 can generate three pulse width modulation (PWM) waveforms based on Clarke inverse transform. These waveforms are then amplified by the inverter bridge module U3 (e.g., a three-phase inverter bridge) to generate the three-phase terminal voltage V. a V b V c This serves as the drive power input to the permanent magnet synchronous motor (PMSM).

[0049] Continue to refer to, for example Figure 2 As shown, with respect to the three-phase terminal voltage V a V b V c The corresponding three-phase current i a i b i cThe Clarke transformation module U4 can be used to generate current i based on the Clarke transformation. α i β , representing the α-axis and β-axis currents in the (α,β) coordinate system, the current i α i β It can be used to generate current i in the Park transformation module U5 q i d , representing the q-axis and d-axis currents in the (q,d) coordinate system.

[0050] like Figure 2 As shown, when the motor is in a stationary position, a high-frequency pulsating voltage U is injected into the d-axis of the observation axis system. m cos(ω i At this point, the q-axis response current contains rotor position information. Therefore, the q-axis current i q The high-frequency response current i is extracted after passing through a bandpass filter (BPF). qh High-frequency response current i qh After sin(ω) i The rotor speed n is obtained by modulating the rotor (t) and passing it through a low-pass filter (LPF) and a proportional-integral (PI) stage. The rotor speed n is then integrated to obtain the rotor position, which is the rotor position when stationary, denoted as θ1. At this point, the rotor position θ1 when stationary can be saved.

[0051] Once the motor starts rotating, obtain the rotor angle of the motor rotor, denoted as θ2. At this point, the motor has already rotated through a certain angle.

[0052] Next, the actual direction of rotation of the permanent magnet synchronous motor can be determined based on the angle difference Δθ = θ2 - θ1, and the actual position of the motor rotor can be determined accordingly. This verifies whether the rotor polarity judgment is correct. If it is correct, it means that the motor is rotating in the given direction. If it is incorrect, it means that the motor is rotating in the wrong direction. At this time, 180° is added to the current high-frequency injection observation rotor position, and the motor resumes normal rotation, thus ensuring that the motor starts correctly.

[0053] The method for determining the actual direction of rotation of the permanent magnet synchronous motor is as follows: Calculate the angular difference between the rotor position θ1 and the rotor angle θ2 when stationary; based on the angular difference and preset first and second angular range conditions, determine whether the angular difference preferentially satisfies the first or second angular range condition; determine the actual direction of rotation of the permanent magnet synchronous motor based on the determination result. The first angular range condition is α < Δθ < β or α - 360° < Δθ < β - 360°, and the second angular range condition is -β < Δθ < -α or 360° - β < Δθ < 360° - α, where Δθ represents the angular difference, and α and β represent the threshold values ​​for the angular difference. It should be noted that the process for determining the actual direction of rotation of the permanent magnet synchronous motor will be further explained when describing the rotor position detection method for the permanent magnet synchronous motor.

[0054] After determining the actual direction of rotation of the permanent magnet synchronous motor, the following operations can be performed: based on the given direction of rotation of the permanent magnet synchronous motor and the determined actual direction of rotation, determine whether the given direction and the actual direction of rotation are the same; when it is determined that the given direction and the actual direction of rotation are the same, determine the actual position of the motor rotor; when it is determined that the given direction and the actual direction of rotation are different, correct the currently detected rotor position (i.e., add 180° to the currently detected rotor position) and determine the actual position of the motor rotor at this time.

[0055] After determining the actual position of the motor rotor, the permanent magnet synchronous motor can be controlled in a closed loop by the controller 2000 to rotate according to a given direction and a given speed.

[0056] The coordinated operation of the controller and memory in the aforementioned electronic device can effectively avoid the problem that existing high-frequency injection algorithms may cause the motor to not rotate in the given direction, thereby ensuring the normal operation of the motor.

[0057] In another aspect, embodiments of the present invention provide a method for detecting the rotor position of a permanent magnet synchronous motor, which can be applied to the electronic devices described above.

[0058] like Figure 3 As shown, the permanent magnet synchronous motor rotor position detection method includes: step S100, injecting a high-frequency pulse voltage into the observation axis system of the permanent magnet synchronous motor, and detecting the rotor position of the permanent magnet synchronous motor when stationary after the injection of the high-frequency pulse voltage; step S200, after the permanent magnet synchronous motor rotates, obtaining the rotor angle of the motor rotor; step S300, calculating the angle difference between the stationary rotor position and the rotor angle, and determining the actual direction of rotation of the permanent magnet synchronous motor and the actual position of the motor rotor based on the angle difference.

[0059] Combination Figure 2 and Figure 3As shown, specifically, in step S100, as Figure 4 As shown, step S100 may include: step S110, injecting a high-frequency pulsating voltage into the observation shaft system of the permanent magnet synchronous motor to obtain a response current; step S120, extracting the response current to obtain a corresponding high-frequency response current; step S130, modulating the high-frequency response current, and obtaining the rotor speed through filtering and proportional-integral operations, and obtaining the corresponding rotor position through subsequent integration operations.

[0060] In this embodiment, a high-frequency pulse voltage U is injected. m cos(ω i The d-axis is connected to the observation axis of the permanent magnet synchronous motor, and a response current is obtained on the q-axis, which contains rotor position information. Simply put, a high-frequency voltage is injected into the d-axis, and the rotor position is detected on the q-axis. Of course, in other embodiments, a high-frequency voltage can also be injected into the q-axis, and the rotor position can be detected on the d-axis. It should be noted that, typically, a high-frequency pulsating voltage is injected into the d-axis, and the rotor position is detected on the q-axis.

[0061] Next, by implementing step S120, the q-axis current i can be... q The corresponding high-frequency response current i is obtained after passing through a bandpass filter (BPF). qh Then, through the implementation of step S130, i.e., the high-frequency response current i qh After sin(ω) i The rotor speed n is obtained by modulating the rotor speed n through a low-pass filter (LPF) and a proportional-integral (PI) stage. The rotor position is obtained by integrating the rotor speed n. This rotor position is the rotor position when stationary, denoted as θ1.

[0062] Continue reading Figure 3 Step S200: After the permanent magnet synchronous motor rotates, obtain the rotor angle of the motor rotor. That is, when the motor starts to rotate, obtain the rotor angle of the motor rotor, denoted as θ2. At this time, the motor has already rotated through a certain angle.

[0063] Alternatively, in one embodiment, as Figure 5 As shown, step S300 may include: step S310, calculating the angle difference between the rotor position when stationary and the rotor angle; step S320, based on the angle difference and preset first angle range conditions and second angle range conditions, determining whether the angle difference preferentially satisfies the first angle range conditions or the second angle range conditions; step S330, determining the actual direction of rotation of the permanent magnet synchronous motor according to the determination result.

[0064] Wherein, the first angle range condition is α<Δθ<β or α-360°<Δθ<β-360°, and the second angle range condition is -β<Δθ<-α or 360°-β<Δθ<360°-α, where Δθ represents the angle difference, and α and β represent the threshold values ​​of the angle difference.

[0065] In this embodiment, the first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°; the second angle range condition is -60° < Δθ < -30° or 300° < Δθ < 330°. Of course, in other embodiments, the upper and lower angle limits in the first and second angle range conditions are usually not small angle values ​​to avoid the motor rotating due to external interference (abnormal fluctuations). Similarly, these values ​​are not large angle values ​​to avoid long waiting times (due to the motor rotating at a large angle, resulting in longer waiting times). Therefore, through reasonable design, the first angle range condition can be set to 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition can be set to -60° < Δθ < -30° or 300° < Δθ < 330°, thereby enabling quick and accurate determination of which angle range condition the angle difference satisfies.

[0066] Optionally, in one embodiment, after step S330, the method may further include: step S340, determining whether the given direction and the actual direction are the same based on the given direction of the permanent magnet synchronous motor and the determined actual direction; step S350, when it is determined that the given direction and the actual direction are the same, determining the actual position of the motor rotor; step S360, when it is determined that the given direction and the actual direction are different, correcting the currently detected rotor position (i.e., adding 180° to the currently detected rotor position), and determining the actual position of the motor rotor at this time.

[0067] The following examples illustrate how to determine the actual direction of rotation of a permanent magnet synchronous motor and, based on this, how to determine the actual position of the motor rotor.

[0068] Combination Figure 6 As shown, Figure 6 This is a schematic diagram of the rotor angle detected in the first case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The first case is when the given direction is forward rotation, and the rotor position θ1 when the motor is stationary is detected to be 90° and the rotor angle θ2 detected after the motor rotates a certain angle is between 120° and 150°.

[0069] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is forward (CCW), the detected rotor position θ1 = 90° when stationary is as follows: after the motor rotates a certain angle, the detected rotor angle θ2 is between 120° and 150°. At this time, the angle difference is 30° < Δθ < 60°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is forward, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the first angle range condition of 30° to 60°. Therefore, the actual direction of rotation of the motor can be determined, which is forward rotation.

[0070] As mentioned above, when the given direction of rotation is forward and the actual direction of rotation is also forward (i.e., both directions are the same), the actual position of the motor rotor when it is stationary is the detected stationary rotor position. In other words, the stationary rotor position θ1 detected by high-frequency injection is the true angle of the motor.

[0071] Combination Figure 7 As shown, Figure 7 This is a schematic diagram of the rotor angle detected in the second case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The second case is that the given direction of rotation is forward, and the rotor position θ1 when stationary is detected is 340° and the rotor angle θ2 detected after the motor rotates a certain angle is between 10° and 40°.

[0072] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is forward (CCW), the detected rotor position θ1 = 340° when stationary is as follows: after the motor rotates a certain angle, the detected rotor angle θ2 is between 10° and 40°. At this time, the angle difference is -330° < Δθ < -300°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is forward, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the first angle range condition of -330° to -300°. Therefore, the actual direction of rotation of the motor can be determined, which is forward rotation.

[0073] As mentioned above, when the given direction of rotation is forward and the actual direction of rotation is also forward (i.e., both directions are the same), the actual position of the motor rotor is determined to be the detected rotor position when stationary. In other words, the stationary rotor position θ1 detected by high-frequency injection is the true angle of the motor.

[0074] Combination Figure 8 As shown, Figure 8This is a schematic diagram of the rotor angle detected in the third case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The third case is when the given direction is forward rotation, and the rotor position θ1 when the motor is stationary is detected to be 90° and the rotor angle θ2 detected after the motor rotates a certain angle is between 30° and 60°.

[0075] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is forward (CCW), the detected rotor position θ1 = 90° when stationary is set. After the motor rotates a certain angle, the detected rotor angle θ2 is between 30° and 60°. At this time, the angle difference is -60° < Δθ < -30°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is forward, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the second angle range condition of -60° to -30°. Therefore, the actual direction of rotation of the motor can be determined, which is reverse rotation.

[0076] As mentioned above, when the given direction of rotation is forward but the actual direction of rotation is reverse (i.e., the two directions are different), the actual position of the motor rotor is determined to be the detected stationary rotor position + 180°. In other words, the stationary rotor position θ1 + 180° detected by high-frequency injection is the true angle of the motor.

[0077] Combination Figure 9 As shown, Figure 9 This is a schematic diagram of the rotor angle detected in the fourth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The fourth case is when the given direction is forward rotation, and the rotor position θ1 when the motor is stationary is detected to be 10° and the rotor angle θ2 detected after the motor rotates a certain angle is between 310° and 340°.

[0078] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is forward (CCW), the detected rotor position θ1 = 10° is at rest. After the motor rotates a certain angle, the detected rotor angle θ2 is between 310° and 340°. At this time, the angle difference is 300° < Δθ < 330°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is forward, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the second angle range condition of 300° to 330°. Therefore, the actual direction of rotation of the motor can be determined, which is reverse rotation.

[0079] As mentioned above, when the given direction of rotation is forward but the actual direction of rotation is reverse (i.e., the two directions are different), the actual position of the motor rotor is determined to be the detected stationary rotor position + 180°. In other words, the stationary rotor position θ1 + 180° detected by high-frequency injection is the true angle of the motor.

[0080] Combination Figure 10 As shown, Figure 10 This is a schematic diagram of the rotor angle detected in the fifth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The fifth case is when the given direction is reversed, and the rotor position θ1 when the motor is stationary is detected to be 90° and the rotor angle θ2 detected after the motor rotates a certain angle is between 30° and 60°.

[0081] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is reverse (CW), the detected rotor position θ1 = 90° when stationary is reached. After the motor rotates a certain angle, the detected rotor angle θ2 is between 30° and 60°. At this time, the angle difference is -60° < Δθ < -30°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is reverse, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the second angle range condition of being between -60° and -30°. Therefore, the actual direction of rotation of the motor can be determined, which is reverse rotation.

[0082] As mentioned above, when the given direction of rotation is reverse and the actual direction of rotation is also reverse (i.e., both directions are the same), the actual position of the motor rotor is determined to be the detected rotor position when stationary. In other words, the stationary rotor position θ1 detected by high-frequency injection is the true angle of the motor.

[0083] Combination Figure 11 As shown, Figure 11 This is a schematic diagram of the rotor angle detected in the sixth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The sixth case is when the given direction is reversed, and the rotor position θ1 when it is stationary is detected to be 10° and the rotor angle θ2 detected after the motor rotates a certain angle is between 310° and 340°.

[0084] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is reverse (CW), the detected rotor position θ1 = 10° when stationary is found. After the motor rotates a certain angle, the detected rotor angle θ2 is between 310° and 340°. At this time, the angle difference is 300° < Δθ < 330°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is reverse, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the second angle range condition of 300° to 330°. Therefore, the actual direction of rotation of the motor can be determined, which is reverse rotation.

[0085] As mentioned above, when the given direction of rotation is reverse and the actual direction of rotation is also reverse (i.e., both directions are the same), the actual position of the motor rotor is determined to be the detected rotor position when stationary. In other words, the stationary rotor position θ1 detected by high-frequency injection is the true angle of the motor.

[0086] Combination Figure 12 As shown, Figure 12 This is a schematic diagram of the rotor angle detected in the seventh case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The seventh case is when the given direction is reversed, and the rotor position θ1 when the motor is stationary is detected to be 90° and the rotor angle θ2 detected after the motor rotates a certain angle is between 120° and 150°.

[0087] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is reverse (CW), the detected rotor position θ1 = 90° when stationary is reached. After the motor rotates a certain angle, the detected rotor angle θ2 is between 120° and 150°. At this time, the angle difference is 30° < Δθ < 60°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is reverse, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the first angle range condition of 30° to 60°. Therefore, the actual direction of rotation of the motor can be determined, which is forward rotation.

[0088] As mentioned above, when the given direction of rotation is reverse but the actual direction of rotation is forward (i.e., the two directions are different), the actual position of the motor rotor is determined to be the detected stationary rotor position + 180°. In other words, the stationary rotor position θ1 + 180° detected by high-frequency injection is the true angle of the motor.

[0089] Combination Figure 13 As shown, Figure 13This is a schematic diagram of the rotor angle detected in the eighth case when the permanent magnet synchronous motor rotor position detection method of the present invention is implemented. The eighth case is when the given direction is reversed, and the rotor position θ1 when it is stationary is detected to be 340° and the rotor angle θ2 detected after the motor rotates a certain angle is between 10° and 40°.

[0090] Specifically, when the given direction of rotation of the permanent magnet synchronous motor is reverse (CW), the detected rotor position θ1 = 340° when stationary is reached. After the motor rotates a certain angle, the detected rotor angle θ2 is between 10° and 40°. At this time, the angle difference is -330° < Δθ < -300°. The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°, and the second angle range condition is set to -60° < Δθ < -30° or 300° < Δθ < 330°. When the given direction of rotation is reverse, the angle difference Δθ between the rotor angle θ2 and the rotor position θ1 first satisfies the first angle range condition of -330° to -300°. Therefore, the actual direction of rotation of the motor can be determined, which is forward rotation.

[0091] As mentioned above, when the given direction of rotation is reverse but the actual direction of rotation is forward (i.e., the two directions are different), the actual position of the motor rotor is determined to be the detected stationary rotor position + 180°. In other words, the stationary rotor position θ1 + 180° detected by high-frequency injection is the true angle of the motor.

[0092] Therefore, when the given direction of rotation of the motor is forward (CCW), after the motor rotates, if the angle difference Δθ first satisfies 30° < Δθ < 60° or -330° < Δθ < -300°, the actual direction of rotation of the motor is determined to be forward (CCW). Thus, the angle θ1 detected when the motor is stationary by high-frequency injection is the true angle of the motor. Conversely, if the angle difference Δθ first satisfies -60° < Δθ < -30° or 300° < Δθ < 330°, the actual direction of rotation of the motor is determined to be reverse (CW). Thus, the angle θ1 + 180° detected when the motor is stationary by high-frequency injection is the true angle of the motor.

[0093] When the given direction of rotation of the motor is reverse (CW), after the motor rotates, if the angle difference Δθ first satisfies -60° < Δθ < -30° or 300° < Δθ < 330°, the actual direction of rotation of the motor is determined to be reverse (CW). Therefore, the angle θ1 detected when the motor is stationary by high-frequency injection is the true angle of the motor. Conversely, if the angle difference Δθ first satisfies 30° < Δθ < 60° or -330° < Δθ < -300°, the actual direction of rotation of the motor is determined to be forward (CCW). Therefore, the angle θ1 + 180° detected when the motor is stationary by high-frequency injection is the true angle of the motor.

[0094] By implementing the above steps S200 to S300 (including steps S310 to S340), it can be verified whether the rotor polarity determination is correct, thereby avoiding the problem that the existing high-frequency injection algorithm may cause the motor to not rotate in the given direction, and thus ensuring the normal operation of the motor.

[0095] Accordingly, some embodiments of the method of the present invention are described below as above, but are not limited thereto.

[0096] Optionally, after performing step S300, the method further includes step S400: after determining the actual position of the motor rotor, the permanent magnet synchronous motor is controlled in a closed loop to rotate according to a given direction and a given speed. In this way, after switching to closed-loop operation, the permanent magnet synchronous motor can adaptively estimate the corresponding current output by the speed loop based on the difference between the rotational speed and the reference speed, so as to fine-tune the rotor speed according to the electrical characteristics of the permanent magnet synchronous motor, enabling the permanent magnet synchronous motor to start correctly and operate smoothly.

[0097] On another front, the present invention provides a rotor position detection device for a permanent magnet synchronous motor, which is applicable to permanent magnet synchronous motors and is used to provide a solution for a permanent magnet synchronous motor that ensures correct start-up and smooth operation, such as a hardware solution.

[0098] like Figure 14 As shown, in one embodiment, the permanent magnet synchronous motor rotor position detection device 5000 may include: a rotor position detection module 5100, a rotor angle acquisition module 5200, and an actual position determination module 5300. The rotor position detection module 5100 is used to inject a high-frequency pulse voltage into the observation axis system of the permanent magnet synchronous motor and detect the rotor position of the permanent magnet synchronous motor when stationary after the high-frequency pulse voltage is injected. The rotor angle acquisition module 5200 is used to acquire the rotor angle of the motor rotor after the permanent magnet synchronous motor rotates. The actual position determination module 5300 is used to calculate the angle difference between the stationary rotor position and the rotor angle, and based on the angle difference, determine the actual direction of rotation of the permanent magnet synchronous motor and, accordingly, determine the actual position of the motor rotor.

[0099] Optionally, in one embodiment, the rotor position detection module 5100 is further configured to inject a high-frequency pulsating voltage into the observation shaft system of the permanent magnet synchronous motor to obtain a response current; extract the response current to obtain a corresponding high-frequency response current; modulate the high-frequency response current and perform filtering and proportional-integral operations to obtain the rotor speed; and obtain the corresponding rotor position through subsequent integration operations.

[0100] Optionally, in one embodiment, the actual position determination module 5300 is further configured to calculate the angle difference between the rotor position when stationary and the rotor angle; based on the angle difference and preset first angle range conditions and second angle range conditions, determine whether the angle difference preferentially satisfies the first angle range conditions or the second angle range conditions; and determine the actual direction of rotation of the permanent magnet synchronous motor according to the determination result.

[0101] Optionally, in one embodiment, the actual position determination module 5300 is further configured to determine whether the given direction and the actual direction are the same based on the given direction of the permanent magnet synchronous motor and the determined actual direction; when it is determined that the given direction and the actual direction are the same, determine the actual position of the motor rotor; when it is determined that the given direction and the actual direction are different, correct the currently detected rotor position and determine the actual position of the motor rotor.

[0102] Optionally, in one embodiment, the permanent magnet synchronous motor rotor position detection device 5000 further includes a motor closed-loop control module, used to control the permanent magnet synchronous motor to rotate according to a given direction and a given speed after determining the actual position of the motor rotor.

[0103] It should be understood that, as Figure 14 As shown, the rotor position detection module 5100, rotor angle acquisition module 5200, and actual position determination module 5300 can achieve the following: Figure 2 The corresponding functions of the various functional modules shown, such as Figure 2 The various functions shown can be appropriately incorporated into the rotor position detection module 5100, rotor angle acquisition module 5200, and actual position determination module 5300, enabling them to operate collaboratively to achieve the following: Figure 2 The relevant steps and contents shown can be found in other embodiments above, and will not be repeated here.

[0104] On the other hand, embodiments of the present invention provide a computer-readable storage medium, hereinafter referred to as a storage medium. The storage medium stores multiple computer programs that can be loaded by a processor to execute steps in a permanent magnet synchronous motor rotor position detection method provided in any embodiment of the present invention. For example, the computer program can execute the following steps:

[0105] Inject a high-frequency pulse voltage into the observation shaft of the permanent magnet synchronous motor and detect the rotor position of the permanent magnet synchronous motor when it is stationary after the high-frequency pulse voltage is injected.

[0106] After the permanent magnet synchronous motor rotates, the rotor angle of the motor rotor is obtained; and

[0107] Calculate the angle difference between the rotor position when stationary and the rotor angle, and based on the angle difference, determine the actual direction of rotation of the permanent magnet synchronous motor and the actual position of the motor rotor accordingly.

[0108] The specific implementation of each of the above operations can be found in the preceding embodiments, and will not be repeated here. The storage medium may include: read-only memory (ROM), random access memory (RAM), a disk, or an optical disk, etc.

[0109] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0110] The present invention provides a detailed description of a method, apparatus, electronic device, and storage medium for detecting the rotor position of a permanent magnet synchronous motor. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of the present invention. 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. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting the rotor position of a permanent magnet synchronous motor, characterized in that, include: Inject a high-frequency pulse voltage into the observation shaft of the permanent magnet synchronous motor and detect the rotor position of the permanent magnet synchronous motor when it is stationary after the high-frequency pulse voltage is injected. Once the permanent magnet synchronous motor rotates, obtain the rotor angle of the motor rotor; as well as Calculate the angle difference between the rotor position when stationary and the rotor angle, and based on the angle difference, determine the actual direction of rotation of the permanent magnet synchronous motor and the actual position of the motor rotor accordingly; The step of calculating the angle difference between the rotor position and the rotor angle when stationary, and determining the actual direction of rotation of the permanent magnet synchronous motor based on the angle difference, includes: Calculate the angular difference between the rotor position when stationary and the rotor angle; Based on the angle difference and the preset first angle range condition and second angle range condition, it is determined that the angle difference preferentially satisfies the first angle range condition or the second angle range condition. The actual direction of rotation of the permanent magnet synchronous motor is determined based on the judgment result; The first angle range condition is α < Δθ < β or α - 360° < Δθ < β - 360°, and the second angle range condition is -β < Δθ < -α or 360° - β < Δθ < 360° - α, where Δθ represents the angle difference, and α and β represent the threshold values ​​of the angle difference.

2. The method for detecting the rotor position of a permanent magnet synchronous motor as described in claim 1, characterized in that, The process of injecting a high-frequency pulsating voltage into the observation shaft system of the permanent magnet synchronous motor and detecting the rotor position of the permanent magnet synchronous motor when it is stationary after the injection of the high-frequency pulsating voltage includes: A high-frequency pulsating voltage is injected into the observation shaft of the permanent magnet synchronous motor to obtain the response current; The response current is extracted to obtain the corresponding high-frequency response current; The high-frequency response current is modulated, filtered, and subjected to proportional-integral operations to obtain the rotor speed, and then subjected to a subsequent integral operation to obtain the corresponding rotor position.

3. The method for detecting the rotor position of a permanent magnet synchronous motor as described in claim 1, characterized in that, The first angle range condition is 30° < Δθ < 60° or -330° < Δθ < -300°; the second angle range condition is -60° < Δθ < -30° or 300° < Δθ < 330°.

4. The method for detecting the rotor position of a permanent magnet synchronous motor as described in claim 1, characterized in that, After determining the actual direction of rotation of the permanent magnet synchronous motor based on the judgment result, the following steps are included: Based on the given direction of the permanent magnet synchronous motor and the determined actual direction of rotation, determine whether the given direction of rotation and the actual direction of rotation are the same; When it is determined that the given direction of rotation is the same as the actual direction of rotation, the actual position of the motor rotor is determined; When it is determined that the given direction of rotation is different from the actual direction of rotation, the currently detected rotor position is corrected, and the actual position of the motor rotor is determined.

5. The method for detecting the rotor position of a permanent magnet synchronous motor as described in claim 4, characterized in that, The method further includes: after determining the actual position of the motor rotor, controlling the permanent magnet synchronous motor to rotate according to a given direction and a given speed in a closed loop.

6. A rotor position detection device for a permanent magnet synchronous motor, characterized in that, include: The rotor position detection module is used to inject high-frequency pulse voltage into the observation shaft system of the permanent magnet synchronous motor and detect the rotor position of the permanent magnet synchronous motor when it is stationary after the high-frequency pulse voltage is injected. The rotor angle acquisition module is used to acquire the rotor angle of the permanent magnet synchronous motor after it rotates. as well as The actual position determination module is used to calculate the angle difference between the rotor position when stationary and the rotor angle, and based on the angle difference, determine the actual direction of rotation of the permanent magnet synchronous motor and the actual position of the motor rotor accordingly. The actual location determination module is further used for: Calculate the angular difference between the rotor position when stationary and the rotor angle; Based on the angle difference and the preset first angle range condition and second angle range condition, it is determined that the angle difference preferentially satisfies the first angle range condition or the second angle range condition. The actual direction of rotation of the permanent magnet synchronous motor is determined based on the judgment result; The first angle range condition is α < Δθ < β or α - 360° < Δθ < β - 360°, and the second angle range condition is -β < Δθ < -α or 360° - β < Δθ < 360° - α, where Δθ represents the angle difference, and α and β represent the threshold values ​​of the angle difference.

7. An electronic device, characterized in that, It includes a controller and a memory, the memory storing one or more programs configured to be executed by the controller as described in any one of claims 1 to 5, for the rotor position detection method of a permanent magnet synchronous motor.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer software instructions that are configured to be executed by a controller using the permanent magnet synchronous motor rotor position detection method as described in any one of claims 1 to 5.

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