Rotor observation method and device of permanent magnet synchronous motor, motor and storage medium

Abstract

The invention discloses a rotor observation method and device of a permanent magnet synchronous motor, a motor and a storage medium, and relates to the technical field of permanent magnet synchronous motor control, and the method comprises the steps: employing a low-speed observer to observe a motor rotor under the condition that the rotating speed of the motor is smaller than a first preset rotating speed, performing closed-loop regulation on the rotating speed of the motor according to an output result of the low-speed observer; when the rotating speed of the motor is increased to be larger than the first preset rotating speed and smaller than the second preset rotating speed, a low-speed observer and a high-speed observer are adopted to observe a motor rotor at the same time, and closed-loop adjustment is conducted on the rotating speed of the motor according to the output result of the low-speed observer; the second preset rotating speed is greater than the first preset rotating speed; and when the rotating speed of the motor is increased to be greater than a second preset rotating speed, obtaining a synthesis result according to the output result of the low-speed observer and the output result of the high-speed observer, and performing closed-loop adjustment on the rotating speed of the motor according to the synthesis result. The method has the effect of improving the stability of the observer switching process.

Description

Technical Field

[0001] This application relates to the technical field of permanent magnet synchronous motor control, and particularly to a rotor observation method, device, motor and storage medium for a permanent magnet synchronous motor. Background Art

[0002] As a compressor of an air conditioner outdoor unit, a permanent magnet synchronous motor mostly adopts a sensorless control method due to limitations in installation space and cost.

[0003] Sensorless control algorithms are generally divided into a model method based on medium and high speeds and a signal injection method based on low speeds. The model method based on medium and high speeds and the signal injection method based on low speeds can be designed into corresponding high-speed observers and low-speed observers for observing the motor rotor for control and switching different observers at different stages of the full speed range of the motor operation.

[0004] However, due to the rapid change of the motor operation state, there is often a switching delay during the process of switching observers, resulting in motor torque fluctuation and affecting the stability and control accuracy of the motor. Summary of the Invention

[0005] The purpose of this application is to solve at least one of the technical problems existing in the prior art, and to provide a rotor observation method, device, motor and storage medium for a permanent magnet synchronous motor, aiming to improve the stability of the observer switching process.

[0006] In a first aspect, an embodiment of this application provides a rotor observation method for a permanent magnet synchronous motor, including: When the motor speed is less than a first preset speed, a low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; When the motor speed rises to be greater than the first preset speed and less than a second preset speed, the low-speed observer and the high-speed observer are simultaneously used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; the second preset speed is greater than the first preset speed; When the motor speed rises to be greater than the second preset speed, a synthesis result is obtained according to the output result of the low-speed observer and the output result of the high-speed observer, and the motor speed is closed-loop regulated according to the synthesis result.

[0007] According to the technical solution of the embodiment of the present application, it has at least the following beneficial effects: The rotational speed range of the motor during operation is usually large, and different observers need to be used at different stages to ensure the accuracy of rotational speed observation. Therefore, when the rotational speed of the motor is less than the second preset rotational speed, the rotational speed of the motor can be closed-loop regulated according to the output result of the low-speed observer. When the rotational speed of the motor rises to be greater than the second preset rotational speed, the observation accuracy of the low-speed observer decreases, and the observer needs to be switched, and the output results of the low-speed observer and the high-speed observer are combined and synthesized to obtain a more accurate output result. However, the high-speed observer usually needs to run for a period of time to enter a stable state. When the rotational speed of the motor rises to be greater than the second preset rotational speed, if the high-speed observer is directly enabled, the observation accuracy of the high-speed observer is unstable at this time, and thus the synthesized result obtained according to the output results of the low-speed observer and the high-speed observer is also unstable. Therefore, before the rotational speed of the motor rises to be greater than the second preset rotational speed, that is, when the rotational speed of the motor rises to be greater than the first preset rotational speed and less than the second preset rotational speed, the high-speed observer is enabled in advance to observe the motor rotor, so that the high-speed observer runs in advance for a period of time but the output result of the high-speed observer is not used. In this way, when the rotational speed of the motor rises to be greater than the second preset rotational speed, since the high-speed observer has run in advance for a period of time and entered a stable state, the synthesized result obtained according to the output results of the low-speed observer and the high-speed observer is relatively stable at this time, thereby improving the stability of the observer switching process.

[0008] According to some embodiments of the present application, obtaining the synthesized result according to the output result of the low-speed observer and the output result of the high-speed observer includes: Compensating the angular velocity output by the low-speed observer according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to obtain a synthesized observed angular velocity.

[0009] According to some embodiments of the present application, the synthesized observed angular velocity is calculated by the following formula: ; Where: is the synthesized observed angular velocity; is the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer; - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the timing duration from the moment when the rotational speed of the motor is equal to the second preset rotational speed to the current moment, is the preset switching duration.

[0010] According to some embodiments of the present application, the synthesis result further includes a synthesized angle obtained by integrating the synthesized observed angular velocity.

[0011] According to some embodiments of the present application, it further includes: When the motor speed rises to be greater than a third preset speed, use the high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer; the third preset speed is greater than the second preset speed.

[0012] According to some embodiments of the present application, when the motor speed rises to be greater than the third preset speed, control the low-speed observer to stop observing.

[0013] The first aspect embodiment of the present application further provides a method for observing the rotor of a permanent magnet synchronous motor, including: When the motor speed is greater than a fourth preset speed, use a high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer; When the motor speed drops to be greater than the third preset speed and less than the fourth preset speed, use both a low-speed observer and the high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer; the fourth preset speed is greater than the third preset speed; When the motor speed drops to be less than the third preset speed, obtain a synthesis result according to the output results of the low-speed observer and the high-speed observer, and perform closed-loop regulation on the motor speed according to the synthesis result.

[0014] According to some embodiments of the present application, the obtaining of the synthesis result according to the output results of the low-speed observer and the high-speed observer includes: Compensate the angular velocity output by the high-speed observer according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to obtain a synthesized observed angular velocity.

[0015] According to some embodiments of the present application, the synthesized observed angular velocity is calculated using the following formula: ; Where: is the synthesized observed angular velocity; is the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer; - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the elapsed time from the moment when the motor speed is equal to the third preset speed to the current moment, is the preset switching duration.

[0016] According to some embodiments of the present application, the synthesis result further includes a synthesized angle obtained by integrating the synthesized observed angular velocity.

[0017] According to some embodiments of the present application, it further includes: When the motor speed drops below the second preset speed, the low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; the third preset speed is greater than the second preset speed.

[0018] According to some embodiments of the present application, when the motor speed drops below the second preset speed, the high-speed observer is controlled to stop observing.

[0019] In a second aspect, an embodiment of the present application provides a rotor observation device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. The processor executes the program to implement the rotor observation method described in the first aspect above.

[0020] In a third aspect, an embodiment of the present application provides a motor, including the rotor observation device described in the second aspect above.

[0021] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, storing computer-executable instructions for causing a computer to execute the rotor observation method as described in the first aspect above.

[0022] Other features and advantages of the present application will be described in the subsequent specification, and part of them will become obvious from the specification, or be understood by implementing the present application. The objectives and other advantages of the present application can be achieved and obtained through the structures specifically pointed out in the specification, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings are used to provide a further understanding of the technical solutions of the present application, and constitute a part of the specification. They are used together with the embodiments of the present application to explain the technical solutions of the present application, and do not constitute a limitation to the technical solutions of the present application.

[0024] The present application will be further described below in conjunction with the drawings and embodiments; Figure 1 is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided by an embodiment of the present application; Figure 2 It is a schematic diagram of the preset speed point of the switching observer in the motor speed rising stage in an embodiment of the present application; Figure 3 It is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided in another embodiment of the present application; Figure 4 It is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided in another embodiment of the present application; Figure 5 It is a schematic diagram of the preset speed point of the switching observer in the motor speed falling stage in an embodiment of the present application; Figure 6 It is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided in another embodiment of the present application; Figure 7 It is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided in another embodiment of the present application; Figure 8 It is a schematic diagram of a rotor observation device for performing the rotor observation method of a permanent magnet synchronous motor provided in an embodiment of the present application; Figure 9 It is a schematic diagram of a rotor observation device for performing the rotor observation method of a permanent magnet synchronous motor provided in another embodiment of the present application. Detailed Description of the Embodiment

[0025] This part will describe the specific embodiments of the present application in detail. The preferred embodiments of the present application are shown in the drawings. The function of the drawings is to supplement the description in the text part of the specification, enabling people to intuitively and vividly understand each technical feature and the overall technical solution of the present application, but it should not be construed as a limitation on the protection scope of the present application.

[0026] In the description of the present application, it should be understood that for the orientation description, such as the orientation or positional relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings, and it is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present application.

[0027] In the description of the present application, the meaning of several is one or more, the meaning of multiple is two or more, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features In the description of this application, unless otherwise clearly defined, terms such as "setting", "installation", "connection", etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in this application in combination with the specific content of the technical solution.

[0028] The following will further elaborate on each embodiment of the rotor observation method of the permanent magnet synchronous motor of this application in conjunction with the attached Figures 1-7 drawings.

[0029] As Figure 1 shown, Figure 1 FIG. is a flowchart of the rotor observation method of the permanent magnet synchronous motor provided by an embodiment of this application. The rotor observation method of the permanent magnet synchronous motor may include, but is not limited to, step S110, step S120, and step S130.

[0030] Step S110: When the motor speed is less than the first preset speed , use a low-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the low-speed observer; Step S120: When the motor speed rises to be greater than the first preset speed and less than the second preset speed , simultaneously use a low-speed observer and a high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the low-speed observer; The second preset speed is greater than the first preset speed ; Step S130: When the motor speed rises to be greater than the second preset speed , obtain a synthesis result according to the output results of the low-speed observer and the high-speed observer, and perform closed-loop regulation on the motor speed according to the synthesis result.

[0031] Those skilled in the art can understand that in the speed closed-loop control system of the permanent magnet synchronous motor, the observer is used to observe the motor rotor to provide estimated information on the position and speed of the motor rotor, and the estimated information on the position and speed of the motor rotor is used to perform closed-loop regulation on the motor speed; In addition, the low-speed observer is used to observe the motor rotor when the speed of the permanent magnet synchronous motor is low, and the high-speed observer is used to observe the motor rotor when the speed of the permanent magnet synchronous motor is high. During the transition process from the low-speed observer to the high-speed observer and from the high-speed observer to the low-speed observer, usually, the low-speed observer and the high-speed observer can be used simultaneously to observe the motor rotor, and by adjusting the weights of the outputs of the low-speed observer and the high-speed observer, gradually switch from using only the low-speed observer to using only the high-speed observer, and gradually switch from using only the high-speed observer to using only the low-speed observer.

[0032] It can be understood that the permanent magnet synchronous motor can be pre - debugged and tested to determine the speed range in which the permanent magnet synchronous motor can operate stably and reliably, so as to determine the speed points for switching the low - speed observer and the high - speed observer; For example, static tests can be carried out. At different speeds (for example, different percentages from 0 to the rated speed), parameters such as the current, voltage, and temperature of the motor are recorded, and it is observed whether the current and voltage are within the rated range, whether the temperature is within the allowable operating range of the motor, then the changing trends of the current and voltage with speed are analyzed, whether there are abnormal fluctuations is checked, whether the temperature rise is proportional to the increase in speed and load, and whether there is overheating is checked, etc., so as to determine the speed range in which the low - speed observer and the high - speed observer can operate stably and reliably, and determine the speed points for switching from the high - speed observer to the low - speed observer and from the low - speed observer to the high - speed observer, as well as the transition interval between the two speed points; Dynamic tests can also be carried out, that is, the motor is accelerated from a stationary state to the rated speed with different accelerations, and decelerated from the rated speed to a stop with different decelerations, and the changes in parameters such as current, voltage, and temperature during the acceleration and deceleration processes are recorded, and it is observed whether the response of the motor during the acceleration process is smooth and whether there is any abnormal vibration or noise; In another embodiment, a mathematical model of the motor can also be established, including electrical, mechanical, and thermal models, etc., and simulation software is used to run the simulation, observe the response of the motor at different speeds, and then analyze the simulation results to predict the performance of the motor during actual operation; In short, through pre - debugging of the permanent magnet synchronous motor, the speed range in which the permanent magnet synchronous motor can operate stably and reliably can be determined. The specific debugging method is not limited here, as long as the speed range in which the permanent magnet synchronous motor can operate stably and reliably can be determined.

[0033] In this embodiment, referring to Figure 2 , Figure 2 is a schematic diagram of the preset speed points for switching observers during the motor speed - rising stage in an embodiment of the present application. Based on the speed - rising stage of the permanent magnet synchronous motor, the speed points for the permanent magnet synchronous motor to switch from the low - speed observer to the high - speed observer that can be determined include the second preset speed . When the motor speed is less than the second preset speed , the permanent magnet synchronous motor can also operate stably and reliably only using the low - speed observer. If the motor speed is greater than the second preset speed , then it is necessary to use both the low - speed observer and the high - speed observer to observe the motor rotor; Thus, it can be seen that when the motor speed is greater than the second preset speed When it is, the high-speed observer is directly enabled. However, due to reasons such as the initial state of the high-speed observer may not be consistent with the state of the actual motor closed-loop control system, the adaptability of the parameters of the high-speed observer to the current operating conditions is relatively low, and the motor closed-loop control system may generate more high-frequency noise when the motor is running at high speed, etc., the high-speed observer may not be stable enough when it is first enabled; Therefore, in this embodiment, a pre-enabled speed point of the high-speed observer before the speed point at which the low-speed observer switches to the high-speed observer during the speed increase stage is set, that is, the first preset speed , when the motor speed is less than the first preset speed , the low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; while when the motor speed rises to be greater than the first preset speed and less than the second preset speed , the high-speed observer is enabled, and only the low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer. In this way, during the speed increase stage, when the motor speed is greater than the first preset speed and less than the second preset speed , the low-speed observer and the high-speed observer run simultaneously. The output of the low-speed observer is used for closed-loop regulation of the motor speed, and the high-speed observer runs in bypass and the output of the high-speed observer does not enter the motor speed closed-loop control system; When the motor speed rises to be greater than the second preset speed , both the low-speed observer and the high-speed observer are used to observe the motor rotor, and a synthesis result is obtained based on the output result of the low-speed observer and the output result of the high-speed observer, so as to perform closed-loop regulation of the motor speed according to the synthesis result; it can be understood that the method of synthesizing the output result of the low-speed observer and the output result of the high-speed observer can include various methods. For example, the output result of the high-speed observer is used to compensate the output result of the low-speed observer in real time and the compensation amount is gradually increased; in another embodiment, the weight of the output result of the high-speed observer can also be gradually increased and the weight of the output result of the low-speed observer can be gradually decreased, or the weights of the output result of the high-speed observer and the output result of the low-speed observer can be dynamically adjusted, or a machine learning algorithm, such as a neural network or a support vector machine, can be introduced to learn the optimal synthesis method of the output results of the low-speed observer and the high-speed observer, etc.

[0034] It can be foreseen that the output results of the low-speed observer and the high-speed observer are used to perform closed-loop regulation of the motor speed in the motor speed closed-loop control system. Therefore, for the first preset speed and the second preset speed The motor speed for comparison is obtained through a low-speed observer and a high-speed observer. Additionally, the input sources of the low-speed observer and the high-speed observer are the same, both being the sampled phase current information of the permanent magnet synchronous motor.

[0035] Those skilled in the art can also foresee that when the motor speed increases to be greater than the second preset speed , a synthesis result is obtained based on the output results of the low-speed observer and the high-speed observer. At this time, the permanent magnet synchronous motor is in a transition state of observer switching. Subsequently, when the motor speed continues to increase, since the permanent magnet synchronous motor has reached a relatively high speed, the accuracy of the low-speed observer drops significantly at a relatively high speed. Therefore, when the motor speed increases to be greater than the second preset speed and greater than another speed point greater than the second preset speed , that is, the speed point at which the transition state ends, the low-speed observer will stop observing the motor rotor; in another embodiment, the speed range of the permanent magnet synchronous motor is small, and when the motor speed increases to be greater than the second preset speed and then continues to increase to reach the rated speed, it will not reach the speed point at which the transition state ends. Therefore, the low-speed observer will not stop observing the motor rotor.

[0036] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of this application, obtaining the synthesis result according to the output results of the low-speed observer and the high-speed observer in the above step S130 may include: compensating the angular velocity output by the low-speed observer according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to obtain a synthesized observed angular velocity.

[0037] It can be understood that the low-speed observer is usually designed based on the mathematical model of the permanent magnet synchronous motor during low-speed operation. When the motor speed increases, the original model may not be able to accurately describe the dynamic behavior of the motor. For example, non-linear factors such as inertial effects, friction, and wind resistance at high speeds may become more significant, and as the speed increases, the electrical and time constants of the motor may change, which will cause the parameters used in the low-speed observer to be no longer accurate, thereby affecting the performance of the observer. Moreover, the design of the low-speed observer may limit its bandwidth, making it unable to quickly respond to high-speed changing states. Additionally, non-linear effects of the motor (such as saturation, cross-coupling, etc.) may become more obvious, and the low-speed observer may not take these non-linear effects into account. Therefore, at high speeds, the accuracy of the low-speed observer may drop, and it may not be able to accurately measure the position and speed of the rotor at high speeds; Meanwhile, during the speed-up stage of the permanent magnet synchronous motor, the high-frequency disturbances and noises in the motor system have a greater impact on speed estimation. Since the dynamic characteristics and nonlinear effects of the motor during high-speed operation may be considered in the design of the high-speed observer, and the high-speed observer is usually designed to have a higher bandwidth and lower noise sensitivity, the high-speed observer has better high-frequency interference suppression, dynamic response, and anti-interference capabilities at high frequencies. Therefore, in some cases, for the stage after the motor speed increases to be greater than the second preset speed the output accuracy of the high-speed observer will be worse than that of the low-speed observer. Therefore, when synthesizing the output results of the low-speed observer and the high-speed observer simultaneously, using the low-speed observer as the main observer and the output result of the low-speed observer as the main output result may have a better effect; Based on this, in this embodiment, the method of synthesizing the output results of the low-speed observer and the high-speed observer is to compensate the output result of the low-speed observer with the output result of the high-speed observer, that is, to use the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to compensate the angular velocity output by the low-speed observer, so as to obtain the synthesized observed angular velocity, so that in the stage after the motor speed increases to be greater than the second preset speed a higher-precision closed-loop regulation of the motor speed can be performed.

[0038] It can be understood that the parameters obtained by the observer observing the motor rotor may include the angular velocity of the rotor. The rotational speed of the rotor can be estimated through the angular velocity of the rotor. Therefore, the synthesis result obtained from the output results of the low-speed observer and the high-speed observer includes the synthesized observed angular velocity, and the rotational speed of the rotor can be estimated using the synthesized observed angular velocity.

[0039] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application, regarding the synthesized observed angular velocity obtained by compensating the angular velocity output by the low-speed observer according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer in the above steps, it is calculated using the following formula: ; Where: is the synthesized observed angular velocity; is the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer; - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is from the moment when the motor speed is equal to the second preset speed to the current timekeeping duration, is a preset switching duration.

[0040] It can be understood that the above formula represents compensating the angular velocity output by the low-speed observer according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer. Among them, - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the timing duration from the moment when the motor speed is equal to the second preset speed to the current moment, is the preset switching duration. Therefore, in the formula can be regarded as the compensation value, can be regarded as the compensation coefficient, can be regarded as the compensation amount; Since is the timing duration from the moment when the motor speed is equal to the second preset speed to the current moment, therefore, the compensation coefficient gradually increases as the speed increases, while the supplementary amount is determined according to the actual angular velocity output by the high-speed observer and the actual angular velocity output by the low-speed observer. The supplementary amount may change linearly or non-linearly, which is mainly determined by the stability of the high-speed observer and the low-speed observer; in addition, it can be understood that the higher the performance and stability of the high-speed observer and the low-speed observer, the smaller the supplementary amount , and the smaller the compensation for the angular velocity output by the low-speed observer.

[0041] In this embodiment, the preset switching duration is obtained through pre-debugging. For example, by observing the duration from only using the low-speed observer to only using the high-speed observer when the permanent magnet synchronous motor runs smoothly throughout the process. The specific debugging method is not limited here, as long as the preset switching duration can be determined.

[0042] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of this application, regarding the above step S130, the synthesis result further includes the synthesized angle obtained by integrating the synthesized observed angular velocity.

[0043] It can be understood that the observer is used to observe the motor rotor to provide estimated information on the position and speed of the motor rotor. The angular velocity output by the observer can be used to estimate the rotational speed of the rotor, and the position of the rotor can be obtained through the angle output by the observer. Therefore, in this embodiment, the synthesis result further includes a synthesized angle obtained by integrating the synthesized observed angular velocity. In one embodiment, the way to obtain the synthesized angle by integrating the synthesized observed angular velocity can be to obtain an angle increment by multiplying the carrier frequency period of the single-chip microcomputer by the output result of the observer corresponding to the current stage, that is, when the motor speed is less than the first preset speed , the angle increment is obtained by multiplying the carrier frequency period of the single-chip microcomputer by the output result of the low-speed observer; when the motor speed rises to be greater than the first preset speed and less than the second preset speed , the angle increment is obtained by multiplying the carrier frequency period of the single-chip microcomputer by the output result of the low-speed observer; when the motor speed rises to be greater than the second preset speed , the angle increment is obtained by multiplying the carrier frequency period of the single-chip microcomputer by the synthesis result; subsequently, the synthesized angle is obtained by adding the current angle increment to the angle increment of each previous time.

[0044] As Figure 3 shown Figure 3 is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided by another embodiment of the present application; regarding the rotor observation method for a permanent magnet synchronous motor, it may further include but is not limited to step S140.

[0045] Step S140: When the motor speed rises to be greater than the third preset speed , use a high-speed observer to observe the motor rotor and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer; the third preset speed is greater than the second preset speed .

[0046] Combined with reference Figure 2 , it can be understood that when the motor speed rises to be greater than the second preset speed , the synthesis result is obtained according to the output results of the low-speed observer and the high-speed observer. At this time, the permanent magnet synchronous motor is in a transition state of observer switching. Subsequently, when the motor speed continues to rise to be greater than the third preset speed , since the permanent magnet synchronous motor has reached a relatively high speed and the accuracy of the low-speed observer decreases significantly at a relatively high speed, when the high-speed observer and the low-speed observer are operating simultaneously, the observation of the motor rotor by both the high-speed observer and the low-speed observer is switched to the observation of the motor rotor only by the high-speed observer, and the output for the closed-loop regulation of the motor speed is switched from the combined result of the output of the low-speed observer and the output of the high-speed observer to the output result of the high-speed observer.

[0047] It can be understood that when the motor speed rises above the third preset speed , the high-speed observer is used to observe the motor rotor, and when the motor speed rises above the second preset speed but less than the third preset speed , both the low-speed observer and the high-speed observer are used to observe the motor rotor. Therefore, when the motor speed is greater than the second preset speed and less than the third preset speed , the motor is in a switching transition state, and the interval where the motor speed is greater than the second preset speed and less than the third preset speed is the transition interval.

[0048] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application, regarding the above step S140, when the motor speed rises above the third preset speed , control the low-speed observer to stop observing.

[0049] It can be understood that when the motor speed continues to rise above the third preset speed , since the permanent magnet synchronous motor has reached a relatively high speed, the accuracy of the low-speed observer decreases significantly at a relatively high speed, and the current motor is in an accelerating state and the motor speed will become higher and higher. Therefore, it is not necessary to use the low-speed observer to observe the motor rotor during the subsequent increase in the motor speed. Thus, when the motor speed continues to rise above the third preset speed , control the low-speed observer to stop observing.

[0050] As Figure 4 shown, Figure 4 is the flowchart of the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application; regarding the rotor observation method of the permanent magnet synchronous motor, it includes but is not limited to step S150, step S160, and step S170.

[0051] Step S150: When the motor speed is greater than the fourth preset speed , use the high-speed observer to observe the motor rotor and perform closed-loop regulation of the motor speed according to the output result of the high-speed observer; Step S160: When the motor speed drops to be greater than a third preset speed and less than a fourth preset speed , simultaneously use a low-speed observer and a high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer; the fourth preset speed is greater than the third preset speed ; Step S170: When the motor speed drops to be less than the third preset speed , obtain a synthesis result according to the output results of the low-speed observer and the high-speed observer, and perform closed-loop regulation on the motor speed according to the synthesis result.

[0052] In this embodiment, referring to Figure 5 , Figure 5 is a schematic diagram of the preset speed points for switching observers during the motor speed drop stage in an embodiment of the present application. Based on the motor speed drop stage of the permanent magnet synchronous motor, the speed points at which the permanent magnet synchronous motor switches from the high-speed observer to the low-speed observer that can be determined include the third preset speed . When the motor speed is greater than the third preset speed , the permanent magnet synchronous motor can operate stably and reliably only using the high-speed observer. If the motor speed is less than the third preset speed , then it is necessary to use both the low-speed observer and the high-speed observer to observe the motor rotor; It can be seen that when the motor speed is less than the third preset speed , the low-speed observer is directly enabled. However, due to reasons such as the initial state of the low-speed observer may not be consistent with the state of the actual motor closed-loop control system, and the adaptability of the parameters of the low-speed observer to the current operating conditions is relatively low, the low-speed observer may not be stable enough when it is first enabled; Therefore, in this embodiment, a pre-enabled low-speed observer speed point before the speed point at which the high-speed observer switches to the low-speed observer during the speed drop stage is set, that is, the fourth preset speed . When the motor speed is greater than the fourth preset speed , use the high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer; when the motor speed drops to be greater than the third preset speed and less than the fourth preset speed , enable the low-speed observer, and only use the high-speed observer to observe the motor rotor, and perform closed-loop regulation on the motor speed according to the output result of the high-speed observer. In this way, when the motor speed during the speed drop stage is greater than the third preset speed and less than the fourth preset speed In the interval, the low-speed observer and the high-speed observer operate simultaneously. The output of the high-speed observer is used for closed-loop regulation of the motor speed, and the low-speed observer operates in bypass and its output does not enter the motor speed closed-loop control system; When the motor speed drops below the third preset speed , both the low-speed observer and the high-speed observer are used to observe the motor rotor, and a synthesis result is obtained based on the output results of the low-speed observer and the high-speed observer, so as to perform closed-loop regulation of the motor speed according to the synthesis result. It can be understood that there are various ways to synthesize the output results of the low-speed observer and the high-speed observer. For example, the output result of the low-speed observer is used to compensate the output result of the high-speed observer in real time and the compensation amount is gradually increased; in another embodiment, the weight of the output result of the low-speed observer can also be gradually increased and the weight of the output result of the high-speed observer can be gradually decreased, or the weights of the output results of the high-speed observer and the low-speed observer can be dynamically adjusted, or a machine learning algorithm, such as a neural network or a support vector machine, can be introduced to learn the optimal synthesis method of the output results of the low-speed observer and the high-speed observer, etc.

[0053] It can be foreseen that the output results of the low-speed observer and the high-speed observer are used to perform closed-loop regulation of the motor speed in the motor speed closed-loop control system. Therefore, the motor speed used for comparison with the third preset speed and the fourth preset speed is obtained through the low-speed observer and the high-speed observer. In addition, the input sources of the low-speed observer and the high-speed observer are the same, both being the sampled phase current information of the permanent magnet synchronous motor.

[0054] Those skilled in the art can also foresee that when the motor speed drops below the third preset speed , a synthesis result is obtained based on the output results of the low-speed observer and the high-speed observer. At this time, the permanent magnet synchronous motor is in the transition state of observer switching. Subsequently, when the motor speed continues to drop, since the permanent magnet synchronous motor has reached a relatively low speed and the accuracy of the high-speed observer drops significantly at a relatively low speed, therefore, when the motor speed drops below the third preset speed and is less than another speed point less than the third preset speed , that is, the speed point at which the transition state ends. In one embodiment, the speed point at which the transition state ends can be the second preset speed , the high-speed observer will stop observing the motor rotor; in another embodiment, the speed range of the permanent magnet synchronous motor is small, and the motor speed drops below the third preset speed After continuing to decline until it stops, it will not reach the rotational speed point at the end of the transition state. Therefore, the high-speed observer will not stop observing the motor rotor.

[0055] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application, obtaining the synthesis result according to the output result of the low-speed observer and the output result of the high-speed observer in the above step S170 may include: compensating the angular velocity output by the high-speed observer according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to obtain the synthesized observed angular velocity.

[0056] It can be understood that during low-speed operation, the back electromotive force of the motor is small because the back electromotive force is proportional to the rotational speed. The high-speed observer is usually designed to process larger signal amplitudes. Therefore, when the rotational speed signal is small, the performance of the high-speed observer may decline. Moreover, due to the small amplitudes of signals such as the back electromotive force, the relative measurement noise has a more significant impact. The high-speed observer may not have sufficient signal-to-noise ratio to accurately estimate the motor state; and at low speeds, the change of motor parameters has a greater impact on the observer. The high-speed observer may not be optimized for the change of motor parameters at low speeds, resulting in an increase in estimation error. In addition, the high-speed observer usually has a relatively high bandwidth to quickly track the change of the motor state. However, at low speeds, the motor state changes slowly, and too high a bandwidth may cause the observer to be too sensitive to noise, leading to instability. Also, the filter in the high-speed observer may be designed to converge quickly, which is an advantage at high speeds but may cause the filter to overreact to the initial error at low speeds and be difficult to stabilize. Therefore, during low-speed operation, the accuracy of the high-speed observer may decline, and it may not be able to accurately measure the position and rotational speed of the rotor at low speeds; At the same time, during the deceleration stage of the permanent magnet synchronous motor, the dynamic change of the motor is relatively small. The low-speed observer may be more effective at low speeds based on a simplified motor model and can provide a stable state estimate. Also, when the motor is operating at low speeds, the dynamic response of the motor system slows down. The low-speed observer can more accurately capture the actual speed change of the motor and is more sensitive to the response of load disturbances at low speeds. Therefore, in some cases, for the stage after the motor rotational speed drops below the third preset rotational speed the output accuracy of the low-speed observer will be worse than the output accuracy of the high-speed observer. Therefore, when synthesizing by using the output results of the low-speed observer and the high-speed observer simultaneously, using the high-speed observer as the main observer and the output result of the high-speed observer as the main output result may have a better effect; Based on this, in this embodiment, the method of synthesizing the output results of the low-speed observer and the high-speed observer is to compensate the output result of the high-speed observer with the output result of the low-speed observer, that is, to use the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to compensate the angular velocity output by the high-speed observer, so as to obtain a synthesized observed angular velocity, so that when the motor speed drops to less than the third preset speed in the subsequent stage, the motor speed can be closed-loop regulated with higher accuracy.

[0057] It can be understood that the parameters obtained by the observer observing the motor rotor may include the angular velocity of the rotor. The speed of the rotor can be estimated through the angular velocity of the rotor. Therefore, the synthesized result obtained from the output results of the low-speed observer and the high-speed observer includes a synthesized observed angular velocity, and the speed of the rotor can be estimated using the synthesized observed angular velocity.

[0058] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application, regarding the synthesized observed angular velocity obtained by compensating the angular velocity output by the high-speed observer with the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer in the above steps, it is calculated using the following formula: ; where: is the synthesized observed angular velocity; is the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer; - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the timing duration from the moment when the motor speed is equal to the third preset speed to the current moment, is the preset switching duration.

[0059] It can be understood that the above formula represents compensating the angular velocity output by the high-speed observer with the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer. Among them, - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the timing duration from the moment when the motor speed is equal to the third preset speed to the current moment, is the preset switching duration. Therefore, in the formula can be regarded as the compensation value, can be regarded as the compensation coefficient. can be regarded as the compensation amount; Since is the timing duration from the moment when the motor speed is equal to the third preset speed to the current moment, therefore, the compensation coefficient gradually increases as the speed increases, while the compensation amount is determined based on the angular velocity actually output by the high-speed observer and the angular velocity actually output by the low-speed observer. The supplementary amount may change linearly or non-linearly, which is mainly determined by the stability of the high-speed observer and the low-speed observer; in addition, it can be understood that the higher the performance and stability of the high-speed observer and the low-speed observer, the smaller the supplementary amount, and the smaller the compensation for the angular velocity output by the high-speed observer.

[0060] In this embodiment, the preset switching duration is obtained through pre-debugging. For example, by observing the duration from when only the high-speed observer is used to when only the low-speed observer is used when the permanent magnet synchronous motor runs smoothly throughout the process. The specific debugging method is not limited here, as long as the preset switching duration can be determined.

[0061] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application, regarding the above step S170, the synthesis result further includes the synthesized angle obtained by integrating the synthesized observed angular velocity.

[0062] It can be understood that the observer is used to observe the motor rotor to provide the estimated information of the motor rotor position and speed. The angular velocity output by the observer can be used to estimate the rotor speed, and the position of the rotor can be obtained through the angle output by the observer. Therefore, in this embodiment, the synthesis result further includes the synthesized angle obtained by integrating the synthesized observed angular velocity. In one embodiment, the way to obtain the synthesized angle by integrating the synthesized observed angular velocity can be to obtain the angle increment by multiplying the carrier frequency period of the single-chip microcomputer by the output result of the observer corresponding to the current stage, that is, when the motor speed is greater than the fourth preset speed , the angle increment is obtained by multiplying the carrier frequency period of the single-chip microcomputer by the output result of the high-speed observer; when the motor speed drops to be greater than the third preset speed and less than the fourth preset speed , the angle increment is obtained by multiplying the carrier frequency period of the single-chip microcomputer by the output result of the high-speed observer; when the motor speed drops to be less than the third preset speed , the angle increment is obtained by multiplying the carrier frequency period of the single-chip microcomputer by the synthesis result; subsequently, the synthesized angle is obtained by adding the current angle increment to the previous angle increments each time.

[0063] Such asFigure 6 As shown Figure 6 is a flowchart of a rotor observation method for a permanent magnet synchronous motor provided by another embodiment of the present application; regarding the rotor observation method of the permanent magnet synchronous motor, it may further include but is not limited to step S180.

[0064] Step S180, when the motor speed drops below a second preset speed , a low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; a third preset speed is greater than the second preset speed .

[0065] With reference to Figure 5 , it can be understood that when the motor speed drops below a third preset speed , a synthesis result is obtained based on the output results of the low-speed observer and the high-speed observer. At this time, the permanent magnet synchronous motor is in a transition state of observer switching. Subsequently, when the motor speed continues to drop below the second preset speed , since the permanent magnet synchronous motor has reached a relatively low speed, the accuracy of the high-speed observer drops significantly at a relatively low speed. Therefore, when the high-speed observer and the low-speed observer are running simultaneously, the observation of the motor rotor by both the high-speed observer and the low-speed observer is switched to only the low-speed observer observing the motor rotor, and the output for closed-loop regulating the motor speed is switched from the synthesis result of the output results of the low-speed observer and the high-speed observer to the output result of the low-speed observer.

[0066] It can be understood that when the motor speed drops below the second preset speed , a low-speed observer is used to observe the motor rotor, and when the motor speed drops below the second preset speed but above the second preset speed , both the low-speed observer and the high-speed observer are used to observe the motor rotor. Therefore, in the range where the motor speed is above the second preset speed and below the third preset speed , the motor is in a switching transition state, and the range where the speed is above the second preset speed and below the third preset speed is the transition range.

[0067] In the rotor observation method of the permanent magnet synchronous motor provided by another embodiment of the present application, regarding the above step S180, when the motor speed drops below the second preset speed , the high-speed observer is controlled to stop observing.

[0068] It can be understood that when the motor speed continues to drop below the second preset speed , since the permanent magnet synchronous motor has reached a relatively low speed, the accuracy of the high-speed observer drops significantly at low speeds, and the current motor is in a decelerating state with the motor speed getting lower and lower. Therefore, during the subsequent motor speed decline, it is also possible not to use the high-speed observer to observe the motor rotor. Thus, when the motor speed continues to drop below the second preset speed , control the high-speed observer to stop observing.

[0069] Reference Figure 7 , Figure 7 is a flowchart of the rotor observation method for a permanent magnet synchronous motor provided by another embodiment of the present application; regarding the rotor observation method of the permanent magnet synchronous motor, during the motor speed rising stage, it may include but is not limited to steps S110, S120, S130, and S140, and during the motor speed falling stage, it may include but is not limited to steps S150, S160, S170, and S180.

[0070] It can be understood that during the motor speed rising stage, when the motor speed is less than the first preset speed , use a low-speed observer to observe the motor rotor and perform closed-loop regulation of the motor speed according to the output result of the low-speed observer; when the motor speed rises above the first preset speed and less than the second preset speed , simultaneously use a low-speed observer and a high-speed observer to observe the motor rotor and perform closed-loop regulation of the motor speed according to the output result of the low-speed observer; when the motor speed rises above the second preset speed and less than the third preset speed , obtain a synthesis result based on the output results of the low-speed observer and the high-speed observer, and perform closed-loop regulation of the motor speed according to the synthesis result; when the motor speed rises above the third preset speed , use a high-speed observer to observe the motor rotor and perform closed-loop regulation of the motor speed according to the output result of the high-speed observer; During the motor speed falling stage, when the motor speed is greater than the fourth preset speed , use a high-speed observer to observe the motor rotor and perform closed-loop regulation of the motor speed according to the output result of the high-speed observer; when the motor speed drops to be greater than the third preset speed and less than the fourth preset speed , simultaneously use a low-speed observer and a high-speed observer to observe the motor rotor and perform closed-loop regulation of the motor speed according to the output result of the high-speed observer; when the motor speed drops to be less than the third preset speed and greater than the second preset speed , a synthesis result is obtained based on the output results of the low-speed observer and the high-speed observer, and the motor speed is closed-loop regulated according to the synthesis result; when the motor speed drops below a second preset speed , the low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer.

[0071] Based on the rotor observation methods of the permanent magnet synchronous motor in the above respective embodiments, the respective embodiments of the rotor observation device, the motor, and the computer-readable storage medium of the present application are respectively proposed below.

[0072] As Figure 8 shown, Figure 8 is a schematic diagram of a rotor observation device for performing the rotor observation method of a permanent magnet synchronous motor provided by an embodiment of the present application.

[0073] In this embodiment, the rotor observation device for performing the rotor observation method of a permanent magnet synchronous motor includes an observer enabling module, a low-speed observer, a high-speed observer, a speed synthesis module, and an integration module, where the observer enabling module is used to determine whether to enable the low-speed observer and the high-speed observer, that is, to enable the low-speed observer, enable the high-speed observer, or enable both the low-speed observer and the high-speed observer; the low-speed observer and the high-speed observer then observe the motor rotor according to the instructions of the observer enabling module; the speed synthesis module is used to determine the output for closed-loop regulation of the motor speed, and synthesize the output results of the low-speed observer and the high-speed observer, that is, use the output result of the low-speed observer to perform closed-loop regulation of the motor speed, use the output result of the high-speed observer to perform closed-loop regulation of the motor speed, and according to the output result of the low-speed observer and the output result of the high-speed observer to obtain a synthesis result , and perform closed-loop regulation of the motor speed according to the synthesis result; the integration module is used to integrate according to the synthesized observed angular velocity output by the speed synthesis module to obtain a synthesized angle .

[0074] As Figure 9 shown, Figure 9 is a schematic diagram of a rotor observation device for performing the rotor observation method of a permanent magnet synchronous motor provided by another embodiment of the present application. The rotor observation device 900 implemented in the present application includes: a processor 920, a memory 910, and a computer program stored on the memory 910 and executable on the processor 920, where Figure 9Taking a processor 920 and a memory 910 as an example.

[0075] The processor 920 and the memory 910 can be connected through a bus or other means. Figure 9 Taking the connection through a bus as an example.

[0076] The memory 910, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. In addition, the memory 910 can include high-speed random access memory, and can also include non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory 910 optionally includes a memory 910 remotely provided relative to the processor 920, and these remote memories 910 can be connected to the rotor observation device 900 through a network. Examples of the above network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0077] Those skilled in the art can understand that Figure 9 the device structure shown in does not constitute a limitation on the rotor observation device 900, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0078] In Figure 9 the rotor observation device 900 shown, the processor 920 can be used to call the control program stored in the memory 910, so as to implement the above-mentioned rotor observation method of the permanent magnet synchronous motor. Specifically, the non-transitory software programs and instructions required to implement the rotor observation method of the permanent magnet synchronous motor in the above embodiments are stored in the memory 910, and when executed by the processor 920, the rotor observation method of the permanent magnet synchronous motor in the above embodiments is executed.

[0079] It should be noted that since the rotor observation device 900 of the embodiment of the present application can execute the rotor observation method of the permanent magnet synchronous motor in any of the above embodiments, therefore, the specific implementation manners and technical effects of the rotor observation device 900 of the embodiment of the present application can refer to the specific implementation manners and technical effects of the rotor observation method of the permanent magnet synchronous motor in any of the above embodiments.

[0080] In addition, an embodiment of the present application further provides a motor, and the motor includes the rotor observation device in the above embodiment.

[0081] It should be noted that since the motor of the embodiment of the present application includes the rotor observation device of the above embodiment, and the rotor observation device of the above embodiment can execute the rotor observation method of the permanent magnet synchronous motor of any of the above embodiments, therefore, the specific implementation manners and technical effects of the motor of the embodiment of the present application can refer to the specific implementation manners and technical effects of the rotor observation method of the permanent magnet synchronous motor of any of the above embodiments.

[0082] In addition, an embodiment of the present application further provides a computer-readable storage medium, which stores computer-executable instructions for executing the above-mentioned rotor observation method of the permanent magnet synchronous motor. Exemplarily, execute the Figure 1 , Figures 3-4 , Figures 6-7 method steps in.

[0083] It should be noted that since the computer-readable storage medium of the embodiment of the present application can execute the rotor observation method of the permanent magnet synchronous motor of any of the above embodiments, therefore, the specific implementation manners and technical effects of the computer-readable storage medium of the embodiment of the present application can refer to the specific implementation manners and technical effects of the rotor observation method of the permanent magnet synchronous motor of any of the above embodiments.

[0084] Those of ordinary skill in the art can understand that all or some of the steps and systems disclosed above can be implemented as software, firmware, hardware and their appropriate combinations. Some physical components or all physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or can be implemented as hardware, or can be implemented as an integrated circuit, such as an application specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include a computer storage medium or a non-transitory medium and a communication medium or a transitory medium. As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information such as computer-readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cassettes, tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, as is well known to those of ordinary skill in the art, communication media typically includes computer-readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and can include any information delivery medium.

[0085] In several embodiments provided by the present application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, indirect couplings or communication connections of apparatuses or units, and can be in electrical, mechanical, or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0086] It should also be understood that the various embodiments provided by the embodiments of the present application can be combined arbitrarily to achieve different technical effects.

[0087] The embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art in the described technical field, various changes can also be made without departing from the purpose of the present application.

Claims

1. A rotor observation method for a permanent magnet synchronous motor, characterized in that: include: When the motor speed is less than a first preset speed, a low-speed observer is used to observe the motor rotor, and a closed-loop regulation is performed on the motor speed according to an output result of the low-speed observer; When the motor speed increases to a value greater than the first preset speed and less than a second preset speed, the motor rotor is observed by the low-speed observer and the high-speed observer at the same time, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; the second preset speed is greater than the first preset speed; When the motor speed increases to be greater than the second preset speed, a synthesis result is obtained according to an output result of the low-speed observer and an output result of the high-speed observer, and the motor speed is closed-loop regulated according to the synthesis result.

2. The rotor observation method according to claim 1, characterized in that: The obtaining a synthesis result according to the output result of the low-speed observer and the output result of the high-speed observer comprises: According to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer, the angular velocity output by the low-speed observer is compensated to obtain a synthetic observed angular velocity.

3. The rotor observation method according to claim 2, characterized in that: The synthetic observed angular velocity is calculated using the following formula: ； in: is the synthetic observed angular velocity; is the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer; - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the time duration from the moment when the motor speed is equal to the second preset speed to the current moment, The preset switching time.

4. The rotor observation method according to claim 2, characterized in that: The synthesis result also includes a synthetic angle obtained by integrating the synthetic observation angular velocity.

5. The rotor observation method according to claim 1, characterized in that: Also includes: When the motor speed increases to be greater than a third preset speed, the high-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the high-speed observer; the third preset speed is greater than the second preset speed.

6. The rotor observation method according to claim 5, characterized in that: When the motor speed increases to be greater than the third preset speed, the low-speed observer is controlled to stop observing.

7. A rotor observation method for a permanent magnet synchronous motor, characterized in that: include: When the motor speed is greater than a fourth preset speed, a high-speed observer is used to observe the motor rotor, and a closed-loop regulation is performed on the motor speed according to an output result of the high-speed observer; When the motor speed drops to a value greater than the third preset speed and less than the fourth preset speed, the motor rotor is observed by the low-speed observer and the high-speed observer at the same time, and the motor speed is closed-loop regulated according to the output result of the high-speed observer; the fourth preset speed is greater than the third preset speed; When the motor speed drops to less than the third preset speed, a synthesis result is obtained according to an output result of the low-speed observer and an output result of the high-speed observer, and the motor speed is closed-loop regulated according to the synthesis result.

8. The rotor observation method according to claim 7, characterized in that: The obtaining a synthesis result according to the output result of the low-speed observer and the output result of the high-speed observer comprises: The angular velocity output by the high-speed observer is compensated according to the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer to obtain a synthetic observed angular velocity.

9. The rotor observation method according to claim 8, characterized in that: The synthetic observed angular velocity is calculated using the following formula: ； in: is the synthetic observed angular velocity; is the difference between the angular velocity output by the high-speed observer and the angular velocity output by the low-speed observer; - , is the angular velocity output by the high-speed observer, is the angular velocity output by the low-speed observer, is the time duration from the moment when the motor speed is equal to the third preset speed to the current moment, The preset switching time.

10. The rotor observation method according to claim 8, characterized in that: The synthesis result also includes a synthetic angle obtained by integrating the synthetic observation angular velocity.

11. The rotor observation method according to claim 7, characterized in that: Also includes: When the motor speed drops to less than the second preset speed, the low-speed observer is used to observe the motor rotor, and the motor speed is closed-loop regulated according to the output result of the low-speed observer; the third preset speed is greater than the second preset speed.

12. The rotor observation method according to claim 11, characterized in that: When the motor speed drops to less than the second preset speed, the high-speed observer is controlled to stop observing.

13. A rotor observation device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the rotor observation method according to any one of claims 1 to 12.

14. A motor, characterized in that: Includes the rotor observation device as described in claim 13.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the rotor observation method according to any one of claims 1 to 12.

Images