Rotational speed fluctuation suppression method for permanent magnet synchronous motor, and operation control apparatus

Abstract

Disclosed in the present application are a rotational speed fluctuation suppression method for a permanent magnet synchronous motor, and an operation control apparatus. The rotational speed fluctuation suppression method comprises: acquiring a q-axis current feedback signal, a d-axis current feedback signal, a q-axis current reference signal and a d-axis current reference signal (S110); obtaining a d-axis voltage reference signal on the basis of the d-axis current reference signal and the d-axis current feedback signal, obtaining a first q-axis voltage reference signal and a second q-axis voltage reference signal on the basis of the q-axis current feedback signal and the q-axis current reference signal, and obtaining a q-axis voltage reference signal on the basis of the first q-axis voltage reference signal and the second q-axis voltage reference signal, wherein the first q-axis voltage reference signal and the second q-axis voltage reference signal are obtained by means of different controllers (S120); and on the basis of the q-axis voltage reference signal and the d-axis voltage reference signal, generating a PWM control signal (S130).

Description

Methods for suppressing speed fluctuations and operation control devices for permanent magnet synchronous motors

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411845477.X, filed on December 13, 2024, entitled "Speed ​​Fluctuation Suppression Method and Operation Control Device for Permanent Magnet Synchronous Motor", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of permanent magnet synchronous motor control technology, and in particular to a method for suppressing speed fluctuations and an operation control device for a permanent magnet synchronous motor. Background Technology

[0004] As the compressor of the outdoor unit of an air conditioner, the permanent magnet synchronous motor has a periodic compression and relaxation working principle, which causes the compressor speed to fluctuate greatly, seriously affecting the control accuracy and stability.

[0005] In related technologies, permanent magnet synchronous motors employ a dual-closed-loop PI (proportional-integral) control system. This system uses PI regulators in the current and speed loops respectively to achieve precise regulation of the motor current and speed, thereby improving the system's dynamic performance and steady-state accuracy. However, traditional dual-closed-loop PI control systems are less effective at suppressing speed fluctuations, which is detrimental to the stable operation of permanent magnet synchronous motors. Summary of the Invention

[0006] The purpose of this application is to at least solve one of the technical problems existing in the prior art, and to provide a method and operation control device for suppressing speed fluctuations of a permanent magnet synchronous motor, which aims to effectively improve the speed fluctuation suppression effect of the permanent magnet synchronous motor.

[0007] In a first aspect, embodiments of this application provide a method for suppressing speed fluctuations in a permanent magnet synchronous motor, comprising:

[0008] Acquire the q-axis current feedback signal and the d-axis current feedback signal, as well as the q-axis current reference signal and the d-axis current reference signal;

[0009] Based on the d-axis current reference signal and the d-axis current feedback signal, the d-axis voltage reference signal is obtained. Based on the q-axis current feedback signal and the q-axis current reference signal, the first q-axis voltage reference signal and the second q-axis voltage reference signal are obtained. Based on the first q-axis voltage reference signal and the second q-axis voltage reference signal, the q-axis voltage reference signal is obtained. The first q-axis voltage reference signal and the second q-axis voltage reference signal are obtained through different controllers.

[0010] The PWM control signal is generated based on the q-axis voltage reference signal and the d-axis voltage reference signal.

[0011] According to the technical solution of the embodiments of this application, at least the following beneficial effects are achieved: In the dual closed-loop PI control system of the permanent magnet synchronous motor, the three-phase current of the motor stator is collected and converted into two-phase q-axis current feedback signals and d-axis current feedback signals. These signals are then input together with the corresponding given q-axis current reference signals and d-axis current reference signals into the corresponding current regulators to obtain q-axis voltage reference signals and d-axis voltage reference signals. The current regulators are used to achieve precise control of the motor. The q-axis voltage reference signal is used to control the torque output of the motor. The torque output of the motor is related to the motor speed. The current regulator can suppress speed fluctuations to a certain extent, but the effect is not ideal. Therefore, after obtaining the q-axis current feedback signal and the q-axis current reference signal, the current regulator is combined with another different current regulator to obtain the first q-axis voltage reference signal and the second q-axis voltage reference signal. By combining the two different current regulators, the variable range of the q-axis voltage reference signal is increased, thereby enhancing the control capability of the motor torque output and the stable control of the motor speed, thus effectively improving the speed fluctuation suppression effect of the permanent magnet synchronous motor.

[0012] According to some embodiments of this application, the first q-axis voltage reference signal is obtained based on a quasi-PR controller, the second q-axis voltage reference signal is obtained based on a first current regulator, and the d-axis voltage reference signal is obtained based on a second current regulator.

[0013] According to some embodiments of this application, the quasi-PR controller is configured in parallel with the first current regulator.

[0014] According to some embodiments of this application, the resonant frequency of the quasi-PR controller is set to the fundamental angular frequency of the permanent magnet synchronous motor in order to suppress the speed fluctuation of the permanent magnet synchronous motor.

[0015] According to some embodiments of this application, the fundamental angular frequency is set based on the operating frequency of the permanent magnet synchronous motor.

[0016] According to some embodiments of this application, the transfer function of the quasi-PR controller is:

[0017] Among them, K p K is a proportional parameter. i For the resonance parameter, ω c ω0 is the cutoff angular frequency, ω0 is the resonant frequency, and ω0 is set as the fundamental angular frequency. By adjusting the proportional parameter, resonant parameter, and cutoff angular frequency, the signal at the fundamental angular frequency is tracked.

[0018] According to some embodiments of this application, the quasi-PR controller suppresses the periodic load pulsation of the permanent magnet synchronous motor by suppressing the speed fluctuation of the permanent magnet synchronous motor.

[0019] According to some embodiments of this application, the waveform of the output of the quasi-PR controller is the same as the waveform of the q-axis current reference signal.

[0020] According to some embodiments of this application, the q-axis voltage reference signal is obtained based on a first q-axis voltage reference signal and a second q-axis voltage reference signal, including:

[0021] The first q-axis voltage reference signal is added to the second q-axis voltage reference signal to obtain the q-axis voltage reference signal.

[0022] According to some embodiments of this application, the q-axis current reference signal and the d-axis current reference signal are obtained based on a speed regulator. The speed regulator obtains the q-axis current reference signal and the d-axis current reference signal by the speed difference between the speed feedback signal and the preset speed reference signal. The speed feedback signal is obtained by a position sensor.

[0023] According to some embodiments of this application, the position sensor is a position observer.

[0024] Secondly, embodiments of this application provide an operation control device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor executes the program to implement the speed fluctuation suppression method of the first aspect described above.

[0025] Thirdly, embodiments of this application provide an electronic device including the operation control device described in the second aspect above.

[0026] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions for causing a computer to perform the speed fluctuation suppression method as described in the first aspect above.

[0027] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the description, claims and drawings. Attached Figure Description

[0028] The accompanying drawings are used to provide a further understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0029] The present application will be further described below with reference to the accompanying drawings and embodiments;

[0030] Figure 1 is a schematic diagram of a current-speed dual closed-loop control system in the prior art;

[0031] Figure 2 is a flowchart of a method for suppressing speed fluctuations in a permanent magnet synchronous motor according to an embodiment of this application;

[0032] Figure 3 is a schematic diagram of the current-speed dual closed-loop control system used in the speed fluctuation suppression method of a permanent magnet synchronous motor provided in an embodiment of this application;

[0033] Figure 4A shows an embodiment of this application where K is changed. p Amplitude-frequency response diagram of the timing-based PR controller;

[0034] Figure 4B shows an embodiment of this application where K is changed. p Phase-frequency response diagram of the timing-accurate PR controller;

[0035] Figure 5A shows an embodiment of this application where ω is changed. c Amplitude-frequency response diagram of the timing-based PR controller;

[0036] Figure 5B shows an embodiment of this application where ω is changed. c Phase-frequency response diagram of the timing-accurate PR controller;

[0037] Figure 6A shows an embodiment of this application where K is changed. i Amplitude-frequency response diagram of the timing-based PR controller;

[0038] Figure 6B shows an embodiment of this application where K is changed. i Phase-frequency response diagram of the timing-accurate PR controller;

[0039] Figure 7A is a simulation result of the current-speed dual closed-loop control system used in the speed fluctuation suppression method of a permanent magnet synchronous motor provided in an embodiment of this application.

[0040] Figure 7B is a simulation result of the output of the current regulator of the current-speed dual closed-loop control system used in the speed fluctuation suppression method of the permanent magnet synchronous motor provided in an embodiment of this application.

[0041] Figure 8 is a flowchart of a method for suppressing speed fluctuations in a permanent magnet synchronous motor according to another embodiment of this application; and

[0042] Figure 9 is a schematic diagram of an operation control device for performing a speed fluctuation suppression method for a permanent magnet synchronous motor according to an embodiment of this application. Detailed Implementation

[0043] This section will describe in detail the specific embodiments of this application. Preferred embodiments of this application are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of this application, but they should not be construed as limiting the scope of protection of this application.

[0044] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0045] In the description of this application, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If the terms "first" and "second" are used, they are merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly specifying the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0046] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0047] The various embodiments of the speed fluctuation suppression method for permanent magnet synchronous motors of this application will be further described below with reference to Figures 1-8.

[0048] As shown in Figure 1, Figure 1 is a schematic diagram of a commonly used current-speed dual closed-loop control system. The inner control loop of the current-speed dual closed-loop control system is the current control loop, and the outer loop is the speed control loop.

[0049] As shown in Figure 2, Figure 2 is a flowchart of a speed fluctuation suppression method for a permanent magnet synchronous motor provided in an embodiment of this application. The speed fluctuation suppression method may include, but is not limited to, steps S110, S120 and S130.

[0050] Step S110: Obtain the q-axis current feedback signal i q and d-axis current feedback signal i d and q-axis current reference signal and d-axis current reference signal

[0051] Step S120: Based on the d-axis current reference signal and d-axis current feedback signal id d-axis voltage reference signal obtained Based on the q-axis current feedback signal i q and q-axis current reference signal Obtain the first q-axis voltage reference signal and the second q-axis voltage reference signal. Based on the first q-axis voltage reference signal and the second q-axis voltage reference signal, obtain the q-axis voltage reference signal. The first q-axis voltage reference signal and the second q-axis voltage reference signal are obtained through different controllers;

[0052] Step S130: Based on the q-axis voltage reference signal and d-axis voltage reference signal Generate PWM control signals.

[0053] In this embodiment, the permanent magnet synchronous motor is controlled by a dual closed-loop control system of current and speed, as shown in Figure 1. The inner loop of the dual closed-loop control system is the current control loop, and the outer loop is the speed control loop. The speed control loop can output current command signals for the q-axis and d-axis, that is, the q-axis current reference signal. and d-axis current reference signal q-axis current reference signal and d-axis current reference signal This information is transmitted to the current control loop, which then regulates the motor speed.

[0054] The current control loop includes two current regulators, which are used to measure the acquired stator A-phase current i of the motor. a and the stator B-phase current i of the motor b After Clarke transform and Park transform respectively, the q-axis current and d-axis current are obtained, which are the q-axis current feedback signals i. q and d-axis current feedback signal i d The d-axis and q-axis currents represent the two components of the motor stator current in the rotating coordinate system, respectively, and are fed back through the q-axis current feedback signal i. q and q-axis current reference signal The current regulator can output the q-axis voltage adjustment amount, which is fed back to the d-axis current feedback signal i. d and d-axis current reference signal The current regulator can output d-axis voltage regulation. The q-axis voltage regulation and d-axis voltage regulation are transmitted to the inverter after inverse Park transformation. They are then used to achieve precise control of the motor's magnetic field and torque through space vector pulse width modulation (SVPWM), thereby achieving precise control of the motor's speed and current.

[0055] Referring to Figure 3, which is a schematic diagram of the current-speed dual closed-loop control system used in the speed fluctuation suppression method of this application, it can be seen from Figures 1 and 3 that the difference between the current-speed dual closed-loop control system used in the speed fluctuation suppression method of this application and the commonly used current-speed dual closed-loop control system is that the current control loop of the current-speed dual closed-loop control system used in the embodiment of this application includes at least three current regulators. The current regulator used to process the q-axis current includes two different first q-axis current regulators and second q-axis current regulators, wherein the first q-axis current regulator is a quasi-PR controller.

[0056] Based on this, it can be understood that the q-axis current feedback signal i q and d-axis current feedback signal i d The q-axis current reference signal is obtained by sampling and processing the three-phase stator current of the motor. and d-axis current reference signal Obtained through a speed control loop;

[0057] d-axis current reference signal and d-axis current feedback signal i d After the difference calculation, the q-axis current regulator is based on the d-axis current reference signal. and d-axis current feedback signal i d The difference is used to calculate the d-axis voltage reference signal.

[0058] q-axis current reference signal and q-axis current feedback signal i qAfter difference calculation, the q-axis current difference signal is obtained. This signal is then input to a first q-axis current regulator and a second q-axis current regulator. These are two different types of current regulators, and they can have different performance characteristics in terms of bandwidth, gain at the fundamental frequency, and frequency response. For example, the first q-axis current regulator may have a larger bandwidth, a larger gain at the fundamental frequency, or both. In one embodiment, for example, the second q-axis current regulator is primarily used to suppress steady-state errors, particularly for rapidly changing periods. While the linear signal may not completely eliminate tracking errors, the first q-axis current regulator is primarily used to control periodic disturbances. Therefore, the first q-axis current regulator has a larger bandwidth and a greater gain at the fundamental frequency. After the q-axis current difference is input to the first and second q-axis current regulators, the second q-axis current regulator mainly tracks and suppresses the DC component in the q-axis current difference signal, while the first q-axis current regulator tracks and suppresses the AC component. Thus, when the motor speed fluctuates, the first q-axis current regulator can effectively suppress speed fluctuations. Therefore, the first q-axis voltage reference signal is obtained through the first q-axis current regulator, and the second q-axis voltage reference signal is obtained through the second q-axis current regulator.

[0059] After obtaining the first q-axis voltage reference signal and the second q-axis voltage reference signal, the first q-axis voltage reference signal and the second q-axis voltage reference signal can be combined to obtain the q-axis voltage reference signal. For example, the sum of the first q-axis voltage reference signal and the second q-axis voltage reference signal can be calculated, and a weighted sum of the first q-axis voltage reference signal and the second q-axis voltage reference signal can be performed; thus, the q-axis voltage reference signal can be obtained. and d-axis voltage reference signal Then, the q-axis voltage reference signal can be... and d-axis voltage reference signal After undergoing inverse Park transformation, the signals are transmitted to the inverter and then used for space vector pulse width modulation (SVPWM) to achieve precise control of the motor's magnetic field and torque, thereby enabling precise control of the motor's speed and current.

[0060] In this embodiment, the first q-axis current regulator and the second q-axis current regulator can be PI regulators with different parameters. The first q-axis current regulator and the second q-axis current regulator can also be current controllers of different types. For example, the first q-axis current regulator is a PI regulator, and the second q-axis current regulator is a PR controller or a quasi-PR controller, etc.

[0061] In this embodiment, the speed fluctuation of the permanent magnet synchronous motor may have various causes, such as power supply voltage fluctuations, unstable power supply frequency, external load factors, or electromagnetic interference from the external environment. In one embodiment, the permanent magnet synchronous motor is used in a compressor. The reason for the speed fluctuation of the permanent magnet synchronous motor is the change in external load, that is, the periodic fluctuation of torque under the compressor load characteristics. In the compressor-based inverter air conditioner, when the permanent magnet synchronous motor drives the roller to compress the refrigerant, the load torque will fluctuate significantly due to the eccentric crankshaft. This torque fluctuation has a periodic repetitive characteristic, and this load characteristic causes the motor's speed and position waveforms to exhibit periodicity. Fluctuations in the q-axis current regulator output are caused by load changes during control. When using a single q-axis current regulator, especially a PI controller, periodic fluctuations caused by the load cannot be completely eliminated. Therefore, the PI controller may cause instability in speed and position waveforms when responding to load changes, particularly with large load variations. The PI controller's response may lag or over-adjust, resulting in uneven position waveforms and speed fluctuations. Furthermore, the PI controller may exhibit overshoot when facing sudden load changes, especially with improper integral limiting settings, which can exacerbate the instability of speed and position waveforms. Therefore, using dual q-axis current regulators, with each regulator acting as a separate controller, can improve the system's disturbance rejection capability and stability, thus mitigating speed fluctuations.

[0062] In another embodiment of the rotational speed fluctuation suppression method provided in this application, the first q-axis voltage reference signal is obtained based on a quasi-PR controller, the second q-axis voltage reference signal is obtained based on a first current regulator, and the d-axis voltage reference signal... Obtained based on the second current regulator.

[0063] In this embodiment, the first q-axis voltage reference signal is obtained based on a quasi-PR controller, and the second q-axis voltage reference signal is obtained based on a first current regulator. That is, the first q-axis current regulator is a quasi-PR controller, the second q-axis current regulator is a first current regulator, and the d-axis current regulator is a second current regulator. The second q-axis current regulator and the d-axis current regulator are the same type of current regulator. In this embodiment, the second q-axis current regulator and the d-axis current regulator can be PI regulators.

[0064] It is understandable that PR control is an abbreviation for proportional resonant control. Proportional resonant control can achieve infinite gain at the resonant frequency, enabling zero steady-state error control at the resonant frequency. However, as the input angular frequency moves away from the resonant frequency, the gain will drop rapidly. In contrast, the quasi-PR control strategy increases the bandwidth near the resonant frequency, enabling zero steady-state error control at the resonant frequency like ideal PR control. It can also solve the problem of poor control performance after the input waveform frequency shifts.

[0065] In another embodiment of the speed fluctuation suppression method provided in this application, the quasi-PR controller is connected in parallel with the first current regulator.

[0066] In this embodiment, the quasi-PR controller and the first current regulator are connected in parallel. The inputs of the quasi-PR controller and the first current regulator are the same, and the output parameter types of the quasi-PR controller and the first current regulator are the same. The outputs of the quasi-PR controller and the first current regulator can be combined to obtain control parameters that can suppress speed fluctuations.

[0067] In another embodiment of the present application, the resonant frequency of the quasi-PR controller is set to the fundamental angular frequency of the permanent magnet synchronous motor in order to suppress the speed fluctuation of the permanent magnet synchronous motor.

[0068] It is understandable that the fundamental angular frequency of a permanent magnet synchronous motor (PMSM) refers to the angular frequency corresponding to the motor's synchronous speed. The fundamental angular frequency of a PMSM is directly related to the motor's synchronous speed. Ideally, when there is no load disturbance, the motor speed will stabilize near the synchronous speed corresponding to the fundamental angular frequency. However, speed fluctuations caused by load changes will be reflected at this frequency. That is, when the load changes, such as a sudden increase or decrease in load, the motor speed will be affected and a disturbance will occur at the fundamental frequency. A quasi-PR controller can increase the bandwidth near the resonant frequency, setting the resonant frequency of the quasi-PR controller to that of the PMSM. The fundamental angular frequency allows the quasi-PR controller to increase its bandwidth near the fundamental angular frequency of the permanent magnet synchronous motor, enabling zero steady-state error tracking of the fundamental component during motor operation. This reduces the impact of load changes on motor speed. Furthermore, setting the resonant frequency of the quasi-PR controller to the fundamental angular frequency of the permanent magnet synchronous motor allows it to have a large gain at the fundamental frequency, effectively suppressing torque ripple and speed fluctuations caused by the fundamental component. In addition, the quasi-PR controller provides high gain at the fundamental frequency and can enhance the system's ability to suppress fundamental frequency disturbances without sacrificing the performance of other frequencies.

[0069] In another embodiment of the present application, the speed fluctuation suppression method is provided, and the fundamental angular frequency is set based on the operating frequency of the permanent magnet synchronous motor.

[0070] It is understandable that when a permanent magnet synchronous motor is running stably, the input waveform frequency of the current regulator on the q-axis is relatively stable, near the motor's operating frequency. However, when the speed of the permanent magnet synchronous motor fluctuates, the input waveform frequency of the current regulator on the q-axis will also fluctuate. Therefore, by combining the first current regulator and the quasi-PR controller in q-axis control, the gain at the operating frequency can be increased, as can the bandwidth near the operating frequency, thus enabling q-axis control to effectively suppress speed fluctuations.

[0071] In another embodiment of the speed fluctuation suppression method provided in this application, the transfer function of the quasi-PR controller is:

[0072] Among them, K p K is a proportional parameter. i For the resonance parameter, ω c ω0 is the cutoff angular frequency, ω0 is the resonant frequency, and ω0 is set as the fundamental angular frequency. By adjusting the proportional parameter, resonant parameter, and cutoff angular frequency, the signal at the fundamental angular frequency is tracked.

[0073] Referring to Figures 4A to 6B, Figures 4A and 4B show the changes in K. p The amplitude-frequency response and phase-frequency response of the time-accurate PR controller, as K p As the gain increases, the quasi-PR controller gains continuously, but the proportion of the resonant part decreases, and the selectivity of the PR controller deteriorates.

[0074] Figures 5A and 5B show the changes in ω. c The amplitude-frequency response and phase-frequency response diagrams of the time-accurate PR controller, changing ω c It has no effect on the gain at low frequencies; only the gain near the fundamental frequency changes accordingly, ω c The larger the value, the greater the controller's bandwidth, and the stronger the controller's ability to handle input waveform frequency offsets;

[0075] Figures 6A and 6B show the changes in K. i The amplitude-frequency response and phase-frequency response of the time-accurate PR controller, as K i As the value increases, the gain at the resonant frequency becomes larger and larger;

[0076] Therefore, by properly selecting the parameters of the quasi-PR controller, it is possible to track signals within a specific frequency range;

[0077] Based on this, in this embodiment, ω0 is set to the fundamental angular frequency, which enables the tracking of signals near the fundamental angular frequency. Furthermore, the quasi-PR controller can provide a large gain, which can effectively suppress fluctuations in motor speed. In addition, by debugging the quasi-PR controller, the proportional parameters, resonant parameters, and cutoff angular frequency can be adjusted to achieve signal tracking at the fundamental angular frequency.

[0078] In another embodiment of the present application, the speed fluctuation suppression method provides that the quasi-PR controller suppresses the speed fluctuation of the permanent magnet synchronous motor and the periodic load pulsation of the permanent magnet synchronous motor.

[0079] In this embodiment, a permanent magnet synchronous motor is used in a compressor. Factors causing speed fluctuations in the permanent magnet synchronous motor include periodic load pulsations, i.e., periodic load pulsations in the compressor. During the compressor's intake, compression, and exhaust phases, the load demand is different, causing the motor to be affected by the load during its working cycle, thus causing speed fluctuations. Therefore, the quasi-PR controller can effectively suppress the periodic load pulsations of the permanent magnet synchronous motor by suppressing its speed fluctuations.

[0080] Referring to Figures 7A and 7B, which are simulation results of the current-speed dual-closed-loop control system used in the speed fluctuation suppression method of this application, Figure 7A shows the speed simulation result of the current-speed dual-closed-loop control system used in the speed fluctuation suppression method of this application, and Figure 7B shows the output simulation result of the current regulator of the current-speed dual-closed-loop control system used in the speed fluctuation suppression method of this application. In the simulation, a permanent magnet synchronous motor is used in the compressor, and the compressor load is set to fluctuate according to the mechanical cycle of the permanent magnet synchronous motor. The simulation test conditions are: for the first 2.5 seconds, only the PI controller is used, the quasi-PR controller is turned off, and after 2.5 seconds, the quasi-PR controller is turned on. As can be seen from Figures 7A and 7B, before the quasi-PR controller is used, the speed fluctuates significantly, fluctuating once per mechanical cycle, which corresponds to the compressor load characteristics; after using the quasi-PR controller, the speed fluctuation is significantly suppressed, proving that the quasi-PR controller has a good effect on suppressing the periodic pulsation of the load.

[0081] In another embodiment of the rotational speed fluctuation suppression method provided in this application, the waveform of the output of the quasi-PR controller is related to the q-axis current reference signal. The waveforms are the same.

[0082] Understandably, the purpose of introducing a quasi-PR controller in the dual closed-loop control system of a permanent magnet synchronous motor is to provide high gain and increase bandwidth at a specific frequency. The speed fluctuations caused by the load of the permanent magnet synchronous motor can be reflected in the q-axis current reference signal. The frequency, that is, reflected in the q-axis current reference signal. On the waveform, therefore, through the q-axis current reference signal The waveform can reveal the signal frequency that the quasi-PR controller needs to track. The quasi-PR controller can be configured to provide high gain and increased bandwidth at specific frequencies that reflect speed fluctuations caused by the load. Thus, the output of the quasi-PR controller applies control to counteract disturbances, and its waveform will correlate with the q-axis current reference signal. The waveforms are the same.

[0083] As shown in Figure 8, Figure 8 is a flowchart of a speed fluctuation suppression method provided in another embodiment of this application; the above step S120 may include, but is not limited to, step S220.

[0084] Step S220: Add the first q-axis voltage reference signal and the second q-axis voltage reference signal to obtain the q-axis voltage reference signal.

[0085] In this embodiment, the first q-axis voltage reference signal and the second q-axis voltage reference signal are combined by adding the first q-axis voltage reference signal and the second q-axis voltage reference signal to calculate the q-axis voltage reference signal. Thus, the q-axis voltage reference signal It includes a first q-axis voltage reference signal for tracking and suppressing the DC component, and a second q-axis voltage reference signal for tracking and suppressing the AC component, such that the q-axis voltage reference signal... It can suppress motor speed fluctuations.

[0086] In another embodiment of the rotational speed fluctuation suppression method provided in this application, the q-axis current reference signal and d-axis current reference signal Based on the speed regulator, the speed regulator obtains the speed feedback signal ω. e and the preset speed reference signal Calculation of q-axis current reference signal for speed difference and d-axis current reference signal Speed ​​feedback signal ω e Obtained through a position sensor.

[0087] In this embodiment, the speed control loop includes a speed regulator and a position sensor. After the position sensor acquires the rotor's estimated speed information, it can calculate the difference between the rotor's estimated position information and the given speed. The speed regulator then uses this difference, i.e., the speed feedback signal ω, to generate the speed feedback signal. e and the preset speed reference signal The speed difference is used to calculate the current command signals for the q-axis and d-axis, i.e., the q-axis current reference signal. and d-axis current reference signal via q-axis current reference signal and d-axis current reference signal This signal is transmitted to the current control loop, which then regulates the motor speed; thus, the q-axis current reference signal... and d-axis current reference signal The position sensor collects the angular velocity of the motor rotor and then processes it.

[0088] In another embodiment of the rotational speed fluctuation suppression method provided in this application, the position sensor is a position observer.

[0089] It is understandable that the position observer is used in sensorless control algorithms to detect the rotor's angular velocity and angle information, thereby obtaining rotor speed estimation information and position estimation information. In permanent magnet synchronous motor control systems, traditional position sensors (such as encoders, Hall sensors, etc.) will increase the cost and installation complexity of the motor. Therefore, in this embodiment, using the position observer as the position sensor can reduce the dependence on physical sensors, thereby reducing cost and system complexity.

[0090] Based on the speed fluctuation suppression methods of the above embodiments, the following presents various embodiments of the operation control device, electronic device, and computer-readable storage medium of this application.

[0091] As shown in Figure 9, which is a schematic diagram of an operation control device for performing a speed fluctuation suppression method for a permanent magnet synchronous motor according to an embodiment of this application, the operation control device 900 implemented in this application includes: a processor 920, a memory 910, and a computer program stored in the memory 910 and executable on the processor 920. In Figure 9, a processor 920 and a memory 910 are used as an example.

[0092] The processor 920 and the memory 910 can be connected via a bus or other means, as shown in Figure 9, which illustrates a connection via a bus.

[0093] 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. Furthermore, the memory 910 may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 910 may optionally include remotely located memories 910 relative to the processor 920, which can be connected to the operation control device 900 via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0094] Those skilled in the art will understand that the device structure shown in FIG9 does not constitute a limitation on the operation control device 900, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0095] In the operation control device 900 shown in Figure 9, the processor 920 can be used to call the control program stored in the memory 910, thereby implementing the speed fluctuation suppression method of the permanent magnet synchronous motor described above. Specifically, the non-transient software program and instructions required to implement the speed fluctuation suppression method of the permanent magnet synchronous motor in the above embodiment are stored in the memory 910. When executed by the processor 920, the speed fluctuation suppression method of the permanent magnet synchronous motor in the above embodiment is executed.

[0096] It is worth noting that, since the operation control device 900 of the embodiments of this application can execute the speed fluctuation suppression method of the permanent magnet synchronous motor in any of the above embodiments, the specific implementation method and technical effects of the operation control device 900 of the embodiments of this application can refer to the specific implementation method and technical effects of the speed fluctuation suppression method of the permanent magnet synchronous motor in any of the above embodiments.

[0097] Furthermore, one embodiment of this application also provides an electronic device that includes the operation control device described in the above embodiment.

[0098] It is worth noting that, since the electronic device of the embodiments of this application includes the operation control device of the above embodiments, and the operation control device of the above embodiments can execute the speed fluctuation suppression method of the permanent magnet synchronous motor of any of the above embodiments, the specific implementation method and technical effects of the electronic device of the embodiments of this application can refer to the specific implementation method and technical effects of the speed fluctuation suppression method of the permanent magnet synchronous motor of any of the above embodiments.

[0099] Furthermore, one embodiment of this application provides a computer-readable storage medium storing computer-executable instructions for performing the aforementioned method for suppressing speed fluctuations in a permanent magnet synchronous motor. Exemplarily, the method steps described in Figures 2 and 8 above are executed.

[0100] It is worth noting that, since the computer-readable storage medium of the embodiments of this application can execute the speed fluctuation suppression method of the permanent magnet synchronous motor in any of the above embodiments, the specific implementation and technical effects of the computer-readable storage medium of the embodiments of this application can be referred to the specific implementation and technical effects of the speed fluctuation suppression method of the permanent magnet synchronous motor in any of the above embodiments.

[0101] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which may include computer storage media or non-transitory media and communication media or transient media. As is known to those skilled in the art, the term computer storage media 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 cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0102] In the several embodiments provided in this application, it should be understood that the disclosed systems, instruments, and methods can be implemented in other ways. For example, the instrument embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the shown or discussed mutual couplings, direct couplings, or communication connections may be through some interfaces; indirect couplings or communication connections between instruments or units may be electrical, mechanical, or other forms. Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, i.e., they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0103] It should also be understood that the various implementation methods provided in the embodiments of this application can be combined arbitrarily to achieve different technical effects.

[0104] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application.

Claims

1. A method for suppressing speed fluctuations in a permanent magnet synchronous motor, comprising: Acquire the q-axis current feedback signal and the d-axis current feedback signal, as well as the q-axis current reference signal and the d-axis current reference signal; A d-axis voltage reference signal is obtained based on the d-axis current reference signal and the d-axis current feedback signal. A first q-axis voltage reference signal and a second q-axis voltage reference signal are obtained based on the q-axis current feedback signal and the q-axis current reference signal. A q-axis voltage reference signal is obtained based on the first q-axis voltage reference signal and the second q-axis voltage reference signal. The first q-axis voltage reference signal and the second q-axis voltage reference signal are obtained through different controllers. A PWM control signal is generated based on the q-axis voltage reference signal and the d-axis voltage reference signal.

2. The method for suppressing rotational speed fluctuations according to claim 1, wherein, The first q-axis voltage reference signal is obtained based on a quasi-PR controller, the second q-axis voltage reference signal is obtained based on a first current regulator, and the d-axis voltage reference signal is obtained based on a second current regulator.

3. The method for suppressing rotational speed fluctuations according to claim 2, wherein, The quasi-PR controller is connected in parallel with the first current regulator.

4. The method for suppressing rotational speed fluctuations according to claim 2 or 3, wherein, The resonant frequency of the quasi-PR controller is set to the fundamental angular frequency of the permanent magnet synchronous motor in order to suppress the speed fluctuation of the permanent magnet synchronous motor.

5. The method for suppressing rotational speed fluctuations according to claim 4, wherein, The fundamental angular frequency is set based on the operating frequency of the permanent magnet synchronous motor.

6. The method for suppressing rotational speed fluctuations according to claim 4 or 5, wherein, The transfer function of the quasi-PR controller is: Among them, K p K is a proportional parameter. i For the resonance parameter, ω c ω0 is the cutoff angular frequency and ω0 is the resonant frequency. ω0 is set as the fundamental angular frequency. By adjusting the proportional parameter, the resonant parameter, and the cutoff angular frequency, the signal at the fundamental angular frequency is tracked.

7. The method for suppressing rotational speed fluctuations according to any one of claims 4 to 6, wherein, The quasi-PR controller suppresses the periodic load pulsation of the permanent magnet synchronous motor by suppressing the speed fluctuation of the permanent magnet synchronous motor.

8. The method for suppressing rotational speed fluctuations according to any one of claims 2 to 7, wherein, The waveform of the output of the quasi-PR controller is the same as the waveform of the q-axis current reference signal.

9. The method for suppressing rotational speed fluctuations according to any one of claims 1 to 8, wherein, The step of obtaining the q-axis voltage reference signal based on the first q-axis voltage reference signal and the second q-axis voltage reference signal includes: The first q-axis voltage reference signal is added to the second q-axis voltage reference signal to obtain the q-axis voltage reference signal.

10. The method for suppressing rotational speed fluctuations according to any one of claims 1 to 9, wherein, The q-axis current reference signal and the d-axis current reference signal are obtained based on a speed regulator. The speed regulator obtains the q-axis current reference signal and the d-axis current reference signal by the speed difference between the speed feedback signal and the preset speed reference signal. The speed feedback signal is obtained by a position sensor.

11. The method for suppressing rotational speed fluctuations according to claim 10, wherein, The position sensor is a position observer.

12. An operation control device, comprising 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 speed fluctuation suppression method as described in any one of claims 1 to 11.

13. An electronic device comprising the operation control device of claim 12.

14. A computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured to cause a computer to perform the speed fluctuation suppression method as described in any one of claims 1 to 11.

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