Permanent magnet synchronous motor control method and device, electronic equipment and storage medium

Abstract

The application provides a permanent magnet synchronous motor control method and device, an electronic device and a storage medium. The method comprises the following steps: driving the permanent magnet synchronous motor to operate in a closed loop based on a field-oriented control mode according to a field weakening parameter; determining a voltage vector composed of a target d-axis voltage and a target q-axis voltage; in response to a magnitude of the voltage vector being less than or equal to a predetermined voltage, controlling the permanent magnet synchronous motor by using the target d-axis voltage and the target q-axis voltage; in response to the magnitude of the voltage vector being greater than the predetermined voltage, determining an adjusted q-axis voltage based on the predetermined voltage and the target d-axis voltage, so that the magnitude of the voltage vector composed of the target d-axis voltage and the adjusted q-axis voltage does not exceed the predetermined voltage, and controlling the permanent magnet synchronous motor by using the target d-axis voltage and the adjusted q-axis voltage and performing field weakening control. Therefore, when the magnitude of the voltage vector is greater than the predetermined voltage, deep field weakening can be achieved. Thus, the problem of unstable control of the existing motor is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet synchronous motor technology, and specifically to a permanent magnet synchronous motor control method, device, and electronic equipment. Background Technology

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

[0003] For example, in field-oriented control (FOC) technology, field weakening control is a method used in permanent magnet synchronous motor control to increase the motor speed.

[0004] In the past, some existing technologies have been proposed, such as the advance angle field weakening technology, which requires both d-axis current loop and q-axis current loop. If one of the current loops is saturated, it can easily lead to control errors, resulting in instability in motor control, which still needs to be improved. Summary of the Invention

[0005] This invention provides a control method, device, electronic equipment, and storage medium for a permanent magnet synchronous motor, which solves the problem of unstable control in existing motors.

[0006] To address the aforementioned problems, one aspect of the present invention provides a control method for a permanent magnet synchronous motor, comprising: driving the permanent magnet synchronous motor into closed-loop operation based on a field-oriented control method; determining the current q-axis current and the current d-axis current; determining a d-axis reference current and a q-axis reference current based on field weakening parameters and the current vector output by the speed loop; determining a target d-axis voltage based on the d-axis reference current and the current d-axis current; determining a target q-axis voltage based on the q-axis reference current and the current d-axis current; determining a voltage vector synthesized by the target d-axis voltage and the target q-axis voltage; and responding to the target d-axis voltage and the target q-axis current... If the magnitude of the voltage vector synthesized by the target d-axis voltage is less than or equal to a predetermined voltage, the permanent magnet synchronous motor is controlled by the target d-axis voltage and the target q-axis voltage; and if the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is greater than the predetermined voltage, an adjusted q-axis voltage is determined based on the predetermined voltage and the target d-axis voltage, such that the magnitude of the voltage vector synthesized by the target d-axis voltage and the adjusted q-axis voltage does not exceed the predetermined voltage, the permanent magnet synchronous motor is controlled by the target d-axis voltage and the adjusted q-axis voltage, and field weakening control is performed.

[0007] In one embodiment, the field weakening control further includes: increasing the field weakening parameter in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being greater than the predetermined voltage and the desired rotational speed being greater than the current rotational speed; and decreasing the field weakening parameter in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being less than or equal to the predetermined voltage or the desired rotational speed being less than or equal to the current rotational speed, wherein the field weakening parameter is an angle in the range from the lower angle limit to the upper angle limit.

[0008] In one embodiment, in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being greater than a predetermined voltage and the desired rotational speed being greater than the current rotational speed, the field weakening parameter is gradually increased according to a step step; in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being less than or equal to the predetermined voltage or the desired rotational speed being less than or equal to the current rotational speed, the field weakening parameter is gradually decreased according to a step step.

[0009] In one embodiment, the step size is an angle ranging from 0.05 degrees to 0.2 degrees.

[0010] In one embodiment, the field weakening parameter is the current vector i output by the rotational speed loop. s The angle β between the d-axis and the q-axis, and the reference current i along the d-axis. s sinβ, the q-axis reference current is i s cosβ.

[0011] In one embodiment, the predetermined voltage magnitude is u m The target d-axis voltage magnitude is u d The magnitude of the adjusted q-axis voltage, determined based on the predetermined voltage and the target d-axis voltage, is:

[0012] In one embodiment, the predetermined voltage is the inverter's rated voltage.

[0013] To address the aforementioned problems, another aspect of the present invention provides a storage medium storing computer software instructions configured to be executed by a controller using the permanent magnet synchronous motor control method described above.

[0014] To address the aforementioned problems, another aspect of the present invention provides a permanent magnet synchronous motor control device, including a controller and a memory, wherein the memory stores one or more programs configured to be executed by the controller using the permanent magnet synchronous motor control method described above.

[0015] To address the aforementioned problems, another aspect of the present invention provides an electronic device including a permanent magnet synchronous motor, an inverter, and a permanent magnet synchronous motor control device as described above.

[0016] In one embodiment, the permanent magnet synchronous motor control device outputs a modulated PWM signal to the inverter so that the inverter outputs three-phase current to the stator winding of the permanent magnet synchronous motor.

[0017] The permanent magnet synchronous motor control method, apparatus, electronic device, and storage medium of the present invention drive the permanent magnet synchronous motor to operate in a closed loop based on a field-oriented control method, determining the current q-axis current and the current d-axis current; determining the d-axis reference current and q-axis reference current based on field weakening parameters and the current vector output by the speed loop; determining the target d-axis voltage based on the d-axis reference current and the current d-axis current; determining the target q-axis voltage based on the q-axis reference current and the current q-axis current; determining the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage; and responding to the target d-axis voltage and the target q-axis current... The magnitude of the voltage vector synthesized by the combined voltages is less than or equal to a predetermined voltage, and the permanent magnet synchronous motor is controlled by the target d-axis voltage and the target q-axis voltage; and in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being greater than the predetermined voltage, an adjusted q-axis voltage is determined based on the predetermined voltage and the target d-axis voltage, such that the magnitude of the voltage vector synthesized by the target d-axis voltage and the adjusted q-axis voltage does not exceed the predetermined voltage, and the permanent magnet synchronous motor is controlled by the target d-axis voltage and the adjusted q-axis voltage, and field weakening control is performed. This invention enables the motor to bypass the q-axis current loop by adjusting the q-axis voltage instead of the target q-axis voltage when the voltage vector value is greater than a predetermined voltage. Field weakening control is then performed by adjusting the d-axis current to adjust the speed, ensuring the speed loop remains operational and achieving deep field weakening. This avoids saturation caused by mutual interference between the two current loops. Furthermore, it ensures the speed loop continues to function after entering the field weakening mode. This invention effectively improves upon existing technologies (such as those requiring two current loops simultaneously), which are prone to control errors due to current loop saturation. It is beneficial for enhancing the level and quality of motor control technology. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic block diagram of a permanent magnet synchronous motor control device according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the current vector when the permanent magnet synchronous motor control device enters the field weakening control according to an embodiment of the present invention.

[0021] Figure 3 This is a flowchart illustrating the permanent magnet synchronous motor control method according to an embodiment of the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] In this description, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] This document provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure of the invention, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided herein, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0025] This invention provides a method, apparatus, and storage medium for controlling a permanent magnet synchronous motor. Examples are given below to illustrate the invention; these descriptions are intended to enable those skilled in the art to understand the invention, but are not intended to limit the scope of the invention.

[0026] In one aspect, embodiments of the present invention provide a permanent magnet synchronous motor control device, which can be applied to execute a permanent magnet synchronous motor control method to provide a permanent magnet synchronous motor control scheme for field weakening control, such as a hardware and software collaborative solution.

[0027] For example, in one embodiment, such as Figure 1As shown, the permanent magnet synchronous motor control device may include a controller U and a memory Y. The memory Y may be, for example, various non-volatile memories, but not limited thereto, or other storage hardware or its derivatives, used to store programs, parameters, or data, etc. The controller U may be a microcontroller unit (MCU) or an application-specific integrated circuit (ASIC) containing its functions, but not limited thereto, or other signal processing hardware or its derivatives, used to control and drive the permanent magnet synchronous motor (PMSM) M. For example, the controller U is electrically connected to the memory Y. The controller U and the memory Y may be separate from each other or integrated. The memory Y stores one or more programs, which are configured to be executed by the controller U using the aforementioned permanent magnet synchronous motor control method.

[0028] For example, such as Figure 1 As shown, the controller U can be configured as a software module, hardware module, software-hardware co-processing module, or other corresponding module with its functions to drive the permanent magnet synchronous motor M. For example, the permanent magnet synchronous motor can be started based on vector control, which can be field-oriented control (FOC) and can be achieved by controlling the three-phase voltage u output by the inverter. a u b u c The amplitude and frequency are used to control a three-phase AC motor, such as a permanent magnet synchronous motor.

[0029] In a field-oriented control architecture, the control of motor torque, speed, and position is mainly achieved by controlling the motor's operating current. It typically includes an inner loop for current control (such as a current loop), a middle loop for speed control (such as a speed loop), and an outer loop for angular position control (such as a position loop). However, it is not limited to these; for example, it may only include a current loop and a speed loop, or it may only include a current loop.

[0030] For example, in Figure 1 In this context, the controller U can be configured to perform functions such as control torque current generation, signal switching, difference calculation, proportional-integral (PI) or proportional-integral-derivative (PID) control, Park inverse transform, Clarke inverse transform, Clarke transform, Park transform, position and speed estimation, speed integration, and position generation in a coordinated manner. This is used to control the permanent magnet synchronous motor M to start in an open-loop manner and then drive the permanent magnet synchronous motor M in a closed-loop manner.

[0031] It should be understood that the various functional modules in the controller U perform different functions, such as proportional, integral, differential, difference calculation, transformation, estimation, etc., and are not limited thereto. The parameters required by the functional modules may be the output results from other modules or the output results from different observers (such as tachometers, ammeters, and voltmeters). Their specific features (such as architecture or algorithms) should be understood by those skilled in the art and will not be described in detail here.

[0032] In this embodiment, such as Figure 1 As shown, the controller U drives the permanent magnet synchronous motor M to start and enter closed-loop operation based on the field-oriented control method. First, it determines the current q-axis current i. q and the current d-axis current i d This is so that it can serve as a basis for subsequent control.

[0033] For example, such as Figure 1 As shown, the three-phase current i of the permanent magnet synchronous motor M can be measured using an ammeter and a tachometer. a i b i c and the current rotational speed ω, then based on the three-phase current i a i b i c Further determine the current q-axis current i q and the current d-axis current i d This invention is not limited to this; other methods can also be used to determine the current q-axis current i. q and the current d-axis current i d .

[0034] Then, as Figure 1 As shown, the controller U can be based on the d-axis reference current. (When no field weakening control is performed, the field weakening parameter β = 0, therefore) ) and the current d-axis current i d Determine the target d-axis voltage u d According to the q-axis reference current (When no field weakening control is performed, the field weakening parameter β = 0, therefore) The current vector i output by the speed loop s ) and the current q-axis current i q Determine the target q-axis voltage u q For example, the d-axis reference current. The current d-axis current i output from the Park transformation module U6 d After performing differential calculations, proportional-integral (PI) calculations are performed to generate the target d-axis voltage u. dThe voltage on the d-axis is used to represent the voltage on the (d,q) coordinate system, so as to facilitate the closed-loop operation of the permanent magnet synchronous motor M by the field-oriented control method of the drive motor; the reference current on the q-axis is used to represent the voltage on the d-axis. The current q-axis current i output from the Park transformation module U6 q After performing differential calculations, proportional-integral (PI) calculations are performed to generate the target q-axis voltage u. q This is used to control the permanent magnet synchronous motor M in the subsequent process. It represents the q-axis voltage in the (d,q) coordinate system, so as to drive the permanent magnet synchronous motor M to operate in a closed loop using the field-oriented control method.

[0035] In this embodiment, such as Figure 1 As shown, the target q-axis voltage u q Target d-axis voltage u d A voltage vector (with magnitude and direction) can be synthesized together, wherein the target q-axis voltage u q and the target d-axis voltage u d An adjustment module U1 can be input to generate the adjusted q-axis voltage u. q’ and adjust the d-axis voltage u d’ For example, if the target d-axis voltage u d and target q-axis voltage u q The magnitude of the combined voltage vector is less than or equal to the predetermined voltage (e.g., the inverter's rated voltage V). inv (i.e., the maximum operating voltage of the inverter), the adjustment module U1 can adjust the d-axis voltage u. d’ It can be equal to the target d-axis voltage u d And let the adjusted q-axis voltage u q’ Equal to the target q-axis voltage u q That is, directly using the target d-axis voltage u d and target q-axis voltage u q Control the permanent magnet synchronous motor M to operate in a closed loop. If the adjusted d-axis voltage u is maintained... d’ Less than or equal to a predetermined voltage (e.g., the inverter's rated voltage V) inv Under the condition of the inverter's maximum operating voltage, the adjustment of the d-axis voltage u d’ It can also be appropriately adjusted to be less than the target d-axis voltage u. d Additionally, the adjustment of the q-axis voltage u... q’ Less than or equal to the current q-axis voltage u q For example, in response to the magnitude of the current voltage vector and the inverter's rated voltage v inv The magnitude relationship, for example, the target d-axis voltage u d and the target q-axis voltage u qThe magnitude of the synthesized voltage vector is greater than the predetermined voltage, based on the current q-axis voltage u. q Generate adapted q-axis voltage u q’ For example, based on the predetermined voltage and the target d-axis voltage u d Determine the adjustment of the q-axis voltage u q’ This makes the target d-axis voltage u d and the adjusted q-axis voltage u q’ The magnitude of the jointly synthesized adaptive voltage vector does not exceed the predetermined voltage (e.g., the inverter's rated voltage V). inv For example, the adjustment of the q-axis voltage u q’ The maximum value is less than the rated voltage v of the inverter. inv This is to prevent the motor's workload from exceeding its rated value.

[0036] For example, such as Figure 1 As shown, the voltage is based on the predetermined voltage and the target d-axis voltage u. d Determine the adjustment of the q-axis voltage u q’ This makes the target d-axis voltage u d and the adjusted q-axis voltage u q’ The magnitude of the jointly synthesized voltage vector does not exceed the predetermined voltage, including: maintaining the target d-axis voltage u. d The target q-axis voltage u remains unchanged; and the target q-axis voltage u is reduced. q To obtain the adjusted q-axis voltage u q’ .

[0037] For example, such as Figure 1 As shown, the predetermined voltage can be set to u. m The target d-axis voltage magnitude is u d Based on the predetermined voltage u m and target d-axis voltage u d The q-axis voltage u can be determined using the following formula. q′ :

[0038] For example, such as Figure 1 As shown, the adjustment of the q-axis voltage u q’ The adjustment of the d-axis voltage u d’ It can be input to the Park inverse transform module U2, used to generate voltage u based on the Park inverse transform. α u β , representing the voltage along the α and β axes in the (α,β) coordinate system; the voltage u α u βThe Clarke inverse transform and space vector PWM (SVPWM) module U3 can be used to generate three pulse width modulation (PWM) voltages based on the Clarke inverse transform, and then the driving capability is increased by the inverter bridge module U4 to generate three-phase terminal voltage u. a u b u c This serves as the drive power input to the permanent magnet synchronous motor (PMSM).

[0039] In this embodiment, such as Figure 1 As shown, for example, the three-phase terminal voltage u can be acquired in real time (e.g., via an ADC). a u b u c The corresponding three-phase current i a i b i c Then, through the Clarke transformation module U5, current i is generated based on the Clarke transformation. α i β , representing the α-axis and β-axis currents in the (α,β) coordinate system, the current i α i β It can be used to generate current i in the Park transformation module U6 q i d , representing the current q-axis and d-axis currents in the (q,d) coordinate system.

[0040] In this embodiment, such as Figure 1 As shown, the voltage u α u β With current i α i β The position and speed estimator U7 can estimate the position θ and speed ω. For example, the position θ and speed ω can be estimated using the Sliding Mode Observer (SMO) algorithm, but it is not limited to this. Other algorithms suitable for sensorless motor control, such as the Luenburger algorithm, can also be used to generate the estimated position θ and the current speed ω of the motor rotor, representing the actual position of the motor rotor. The calculation process is understandable to those skilled in the art and will not be elaborated here. In some embodiments, the position θ and current speed ω of the motor rotor can be obtained by sensors, such as encoders or Hall sensors. The current speed ω and the reference speed ω ref The difference (also referred to as the desired speed in this paper) can be subjected to proportional-integral (PI) control to generate a current vector i as the output of the speed loop. s (Also known as reference current, i) ref Furthermore, the field weakening parameter β and the current vector i can be used as a basis for further analysis. sThe d-axis reference current can be determined. and q-axis reference current In one embodiment, the estimated position θ can be used as an input parameter for the Park inverse transform module U2 and the Park transform module U6; furthermore, the reference rotational speed ω ref It can be the estimated position θ and the reference position θ ref The difference is used to perform a proportional-integral (PI) calculation on the output value (which serves as the output of the outer loop's position loop); it is worth noting that, Figure 1 This is an implementation including a position loop; in an embodiment without a position loop, the reference rotational speed ω ref It can also be given directly from the outside.

[0041] Before the permanent magnet synchronous motor M reaches voltage saturation (e.g., the target d-axis voltage u), d and target q-axis voltage u q The magnitude of the combined voltage vector is less than or equal to the predetermined voltage u. m (At this time), various control methods can be used, such as d-axis reference current. Controls include constant zero voltage control (i.e., no field weakening control), maximum torque-to-current ratio control, and maximum output power control. When voltage saturation is reached (e.g., target d-axis voltage u), [the control is applied]. d and target q-axis voltage u q The magnitude of the combined voltage vector is greater than the predetermined voltage u. m After that, the desired rotational speed ω ref If the current is still greater than the current speed ω, and the current speed ω needs to be further increased, then field weakening control can be performed (where the current on the d-axis is greater than 0 for excitation control; and the current on the d-axis is less than 0 for field weakening control). Figure 2 This is a schematic diagram of the current vector after the permanent magnet synchronous motor control device enters field weakening control according to an embodiment of the present invention. For example, if the rotation direction is D1, the included angle β starts from 0° and increases, and can be repeatedly adjusted, but the maximum value does not exceed 90°. The included angle β will affect the current vector i s The current is assigned to the q / d axis as the q / d axis reference current, where the q-axis reference current is... d-axis reference current Angle β equals 0°, current vector i s All currents are allocated to the q-axis; when β equals 90°, all currents are allocated to the d-axis. Therefore, the current vector i output by the speed loop can be determined. s The angle β between the field weakening parameter and the q-axis represents the depth of entry into field weakening control and can be used as a field weakening parameter (but the invention is not limited to this). The field weakening parameter is an angle ranging from a lower limit (e.g., 0 degrees) to an upper limit (e.g., 90 degrees), and the initial value of the field weakening parameter can be set to 0 degrees. In summary, after entering field weakening control, the field weakening parameter β increases from 0, based on the field weakening parameter β (β>0 after entering field weakening) and the current vector i output by the speed loop.s The d-axis reference current can be determined. and q-axis reference current

[0042] Now return to the reference Figure 1 After the field weakening control is started, it will still be based on the d-axis reference current. and the current d-axis current i d Determine the target d-axis voltage u d (Through the d-axis current loop), based on the q-axis reference current and the current q-axis current i q Determine the target q-axis voltage u q (Through the q-axis current loop).

[0043] As mentioned above, the adaptation module U1 of this invention generates the adapted q-axis voltage u. q’ and adjust the d-axis voltage u d’ In response to the target d-axis voltage u d and target q-axis voltage u q The magnitude of the combined voltage vector is less than or equal to the predetermined voltage u. m (For example Then, the target d-axis voltage u d and target q-axis voltage u q Controlling the permanent magnet synchronous motor, i.e., adjusting module U1 to adjust the d-axis voltage u d’ Equal to the target d-axis voltage u d And adjust the q-axis voltage u q’ It is also equal to the target q-axis voltage u q Additionally, in response to the target d-axis voltage u d and target q-axis voltage u q The magnitude of the combined voltage vector is greater than the predetermined voltage u. m (For example The adjustment module U1 is based on a predetermined voltage u m and target d-axis voltage u d Determine the adjustment of the q-axis voltage u q’ This makes the target d-axis voltage u d and adjusting the q-axis voltage u q’ The magnitude of the jointly synthesized adaptive voltage vector does not exceed the predetermined voltage u. m For example, let That is to say, if Then the adjustment module U1 still adjusts the d-axis voltage u. d’ Equal to the target d-axis voltage u d But let With the target d-axis voltage u d and adjusting the q-axis voltage u q’To control the permanent magnet synchronous motor, when the voltage vector reaches saturation, the adjustment module U1 will adjust the q-axis current loop (outputting the target q-axis voltage u). q Bypassing it renders it ineffective in providing rotational energy to the motor, in order to u q′ Replace u q Control the permanent magnet synchronous motor M, but the d-axis current loop (output is the target d-axis voltage u) d You can begin field weakening control (adjusting the field weakening parameter β) and adjust the d-axis reference current. To adjust the rotational speed ω to further increase it.

[0044] like Figure 1 As shown, if the target d-axis voltage u d and the target q-axis voltage u q If the magnitude of the synthesized voltage vector is greater than the predetermined voltage, and if it is necessary to further increase the current rotational speed ω, then a field weakening mode is activated, for example, "the target d-axis voltage u..." d and the target q-axis voltage u q If the magnitude of the synthesized voltage vector is greater than the predetermined voltage and the desired rotational speed is greater than the current rotational speed ω, the field weakening parameter β can be increased. For example, the field weakening parameter β can be gradually increased according to the step Δβ to increase the depth of field weakening control, thereby further increasing the current rotational speed ω. The step Δβ can be an angle in the range of 0.05 degrees to 0.2 degrees, such as 0.05 degrees, 0.1 degrees, 0.15 degrees, or 0.2 degrees, but is not limited thereto. The value of the step Δβ can be increased or decreased as needed. In other cases, such as when the target d-axis voltage u... d and the target q-axis voltage u q If the magnitude of the synthesized voltage vector is less than or equal to the predetermined voltage or the desired rotational speed is less than or equal to the current rotational speed ω, the field weakening parameter β can be reduced. For example, the field weakening parameter β can be gradually reduced according to the step Δβ to reduce the depth of field weakening control, and further reduce the current rotational speed ω to gradually exit field weakening control.

[0045] For example, such as Figure 1 As shown, in the field weakening control mode, the d-axis reference current and the q-axis reference current This serves as the reference current for field weakening control. For example, the target d-axis voltage u... d and target q-axis voltage u q The signal is sent to a field weakening control module Ua, which can perform the following functions: based on the target d-axis voltage u in the (k-1)th iteration. d and target q-axis voltage u qTo generate the magnetic weakening parameter β(k) for the kth iteration, β(k) = f(u q (k-1),u d (k-1)), where k is a positive integer, for example, in the target d-axis voltage u d and the target q-axis voltage u q If the magnitude of the synthesized voltage vector is greater than the predetermined voltage, and the desired rotational speed ω is determined... ref If the rotational speed is greater than the current rotational speed ω, the field weakening parameter β can be gradually increased or decreased according to the step Δβ (e.g., 0.1 degrees) as the source of the reference current for the q-axis and d-axis. For example, a sine wave calculation module Ub can be used to calculate the field weakening parameter β output by the field weakening control module Ua and the current vector i output by the speed loop. s Generate d-axis reference current The cosine operation module Uc calculates the field weakening parameter β output by the field weakening control module Ua and the current vector i output by the velocity loop. s Generate q-axis reference current The voltage u used to generate the q-axis later q u q’ and the voltage u on the d-axis d u d’ This is the basis for driving the motor to rotate based on the field weakening control mode.

[0046] It should be noted that after entering the field weakening control mode, if the field weakening parameter β is gradually increased with the current rotational speed ω, causing the output current vector to shift towards the negative half-axis of the d-axis, when the current loop reaches saturation (for example, when the magnitude of the aforementioned voltage vector is greater than the predetermined voltage u), m (At that time), the present invention adjusts the q-axis voltage u by adjusting the target q-axis voltage. q’ (For example The replacement allows the q-axis current loop to be considered a bypass, while the output current vector i of the speed loop... s As the field weakening parameter β increases, it gradually switches to being generated based on the d-axis current loop. This allows the current rotational speed ω to be adjusted by adjusting the d-axis current even when the voltage vector is greater than a predetermined voltage, ensuring that the rotational speed loop can still operate. This avoids the two current loops from interfering with each other and causing saturation. At the same time, the current rotational speed can be adjusted by adjusting the d-axis current, achieving deep field weakening.

[0047] On the other hand, embodiments of the present invention provide an electronic device, including a permanent magnet synchronous motor, an inverter, and a permanent magnet synchronous motor control device embodiment as described above. The electronic device can be configured into different forms of electric equipment as needed, such as an electric washing machine or an electric vehicle (such as an electric vehicle), but is not limited thereto.

[0048] Optionally, in one embodiment, the permanent magnet synchronous motor control device outputs a modulated PWM signal to the inverter, causing the inverter to output three-phase current to the stator winding of the permanent magnet synchronous motor. Thus, using the aforementioned permanent magnet synchronous motor control mode, the inverter can output three-phase current to the stator winding of the permanent magnet synchronous motor, driving the rotor of the permanent magnet synchronous motor to rotate and provide power.

[0049] On the other hand, embodiments of the present invention provide a permanent magnet synchronous motor control method, which can be applied to the permanent magnet synchronous motor (PMSM) control device described above, for example, the permanent magnet synchronous motor control method embodiment is executed by the permanent magnet synchronous motor control device embodiment.

[0050] Accordingly, such as Figure 3 As shown, the embodiment of the permanent magnet synchronous motor control method includes a current determination step T1, a reference current determination step T2, a target voltage determination step T3, a voltage vector determination step T4, a first motor control step T5, and a second motor control step T6.

[0051] For example, such as Figure 3 As shown, the current current determination step T1 can be based on the closed-loop operation of the permanent magnet synchronous motor driven by the field-oriented control method to determine the current q-axis current and the current d-axis current; the reference current determination step T2 can be based on the field weakening parameters and the current vector i output by the speed loop. s The process involves several steps: First, determining the d-axis reference current and q-axis reference current; second, determining the permanent magnet synchronous motor (PMSM) based on the predetermined voltage and target d-axis voltage; third, determining the target q-axis voltage based on the predetermined voltage and target d-axis voltage; fourth, determining the voltage vector synthesized by the target d-axis voltage and target q-axis voltage; fifth, controlling the PSM based on the target d-axis voltage and target q-axis voltage when the magnitude of the voltage vector synthesized by the target d-axis voltage and target q-axis voltage is less than or equal to a predetermined voltage; sixth, controlling the PSM based on the target d-axis voltage and target d-axis voltage when the magnitude of the voltage vector synthesized by the target d-axis voltage and target q-axis voltage is greater than the predetermined voltage; seventh, determining an adjusted q-axis voltage such that the magnitude of the voltage vector synthesized by the target d-axis voltage and adjusted q-axis voltage does not exceed the predetermined voltage; and finally, controlling the PSM based on the target d-axis voltage and adjusted q-axis voltage, and performing field weakening control.

[0052] In addition, such as Figure 3As shown, the embodiment of the permanent magnet synchronous motor control method may further include a field weakening parameter iteration step T7, used to adjust the field weakening control parameters. For example, the field weakening parameter iteration step T7 may include increasing the field weakening parameter in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being greater than the predetermined voltage and the desired speed being greater than the current speed, and decreasing the field weakening parameter in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being less than or equal to the predetermined voltage or the desired speed being less than or equal to the current speed, wherein the field weakening parameter is an angle in the range from the lower angle limit to the upper angle limit.

[0053] The embodiment of the permanent magnet synchronous motor control method can be executed by the embodiment of the permanent magnet synchronous motor control device described above.

[0054] Accordingly, some embodiments of the permanent magnet synchronous motor control method of the present invention can be described below, but are not limited thereto.

[0055] Optionally, in one embodiment, the field weakening control further includes: increasing the field weakening parameter in response to a voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being greater than a predetermined voltage and a desired rotational speed being greater than the current rotational speed; and decreasing the field weakening parameter in response to a voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being less than or equal to the predetermined voltage or the desired rotational speed being less than or equal to the current rotational speed, wherein the field weakening parameter is an angle within a range from a lower angle limit to an upper angle limit. Thus, the field weakening depth can be fine-tuned using the field weakening parameter increase or decrease mechanism, thereby adjusting the rotational speed using the field weakening depth.

[0056] Optionally, in one embodiment, in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being greater than a predetermined voltage and the desired rotational speed being greater than the current rotational speed, the field weakening parameter is gradually increased according to a step step; in response to the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage being less than or equal to the predetermined voltage or the desired rotational speed being less than or equal to the current rotational speed, the field weakening parameter is gradually decreased according to a step step. Thus, after entering the field weakening operating mode, the reference current can be adjusted through the field weakening parameter, and the rotational speed can be adjusted using the reference current.

[0057] Optionally, in one embodiment, the step size is an angle ranging from 0.05 degrees to 0.2 degrees. Thus, by gradually changing the field weakening parameters in steps within this range (e.g., 0.1 degrees, but not limited to this), the motor speed gradually increases or decreases under reasonable motor operating conditions, avoiding damage to the motor's electrical control components caused by excessively rapid speed adjustments.

[0058] Optionally, in one embodiment, the field weakening parameter is the current vector i output by the rotational speed loop. s The angle β between the d-axis and the q-axis, and the reference current i along the d-axis. s sinβ, the q-axis reference current is i s cosβ. Therefore, the d-axis reference current and q-axis reference current can be adjusted using the aforementioned field weakening parameters, serving as the basis for controlling the motor rotation.

[0059] Optionally, in one embodiment, the predetermined voltage magnitude is u m The target d-axis voltage magnitude is u d The magnitude of the adjusted q-axis voltage, determined based on the predetermined voltage and the target d-axis voltage, is: Therefore, the q-axis voltage can be adjusted through simple calculations to ensure that energy is preferentially reserved for the d-axis voltage.

[0060] Optionally, in one embodiment, the predetermined voltage is the inverter's rated voltage. This ensures that the motor operating voltage does not exceed a load-bearing voltage limit, such as the inverter's rated voltage.

[0061] On the other hand, embodiments of the present invention provide a storage medium storing computer software instructions, such as those implemented in C or other programming languages, which are applicable to being configured to be executed by a controller using the permanent magnet synchronous motor control method described above.

[0062] In summary, the permanent magnet synchronous motor control method, apparatus, electronic device, and storage medium of this invention drive the permanent magnet synchronous motor into closed-loop operation based on a field-oriented control method, determining the current q-axis current and current d-axis current; determining the d-axis reference current and q-axis reference current based on field weakening parameters and the current vector output by the speed loop; determining the target d-axis voltage based on the d-axis reference current and current d-axis current, determining the target q-axis voltage based on the q-axis reference current and current q-axis current; determining the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage; and responding to the target d-axis voltage and the current q-axis reference current... If the magnitude of the voltage vector synthesized by the target q-axis voltage is less than or equal to a predetermined voltage, the permanent magnet synchronous motor is controlled by the target d-axis voltage and the target q-axis voltage; and if the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is greater than the predetermined voltage, an adjusted q-axis voltage is determined based on the predetermined voltage and the target d-axis voltage, such that the magnitude of the voltage vector synthesized by the target d-axis voltage and the adjusted q-axis voltage does not exceed the predetermined voltage, the permanent magnet synchronous motor is controlled by the target d-axis voltage and the adjusted q-axis voltage, and field weakening control is performed.

[0063] The above embodiments of the present invention can, when the magnitude of the voltage vector is greater than the predetermined voltage, use the adjusted q-axis voltage instead of the target q-axis voltage to control the motor to bypass the q-axis current loop, and adjust the speed by adjusting the d-axis current to perform field weakening control. This ensures that the speed loop can still work, achieving deep field weakening. When the q-axis current loop fails, it avoids the two current loops from affecting each other and causing saturation. At the same time, by adjusting the speed by adjusting the d-axis current, it can be ensured that the speed loop can still function after entering the field weakening working mode.

[0064] Therefore, by ensuring that the speed loop can still function after entering the field weakening working mode, the embodiments of the present invention can indeed improve the control error caused by current loop saturation in existing technologies (such as those requiring two current loops at the same time), which is conducive to improving the level and quality of motor control technology.

[0065] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0066] The embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the embodiments above are only for the purpose of helping to understand the technical solutions and core ideas of the present invention. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for a permanent magnet synchronous motor, characterized in that, include: The permanent magnet synchronous motor is driven into closed-loop operation based on the field-oriented control method to determine the current q-axis current and the current d-axis current. The d-axis reference current and q-axis reference current are determined based on the field weakening parameters and the current vector output by the speed loop. The target d-axis voltage is determined based on the d-axis reference current and the current d-axis current, and the target q-axis voltage is determined based on the q-axis reference current and the current q-axis current. Determine the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage; In response to the fact that the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is less than or equal to a predetermined voltage, the permanent magnet synchronous motor is controlled by the target d-axis voltage and the target q-axis voltage; as well as In response to the fact that the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is greater than the predetermined voltage, an adjusted q-axis voltage is determined based on the predetermined voltage and the target d-axis voltage, such that the magnitude of the voltage vector synthesized by the target d-axis voltage and the adjusted q-axis voltage does not exceed the predetermined voltage. The permanent magnet synchronous motor is controlled by the target d-axis voltage and the adjusted q-axis voltage, and field weakening control is performed. When the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is greater than a predetermined voltage and the desired rotational speed is greater than the current rotational speed, the field weakening parameter is gradually increased according to the step step; when the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is less than or equal to the predetermined voltage or the desired rotational speed is less than or equal to the current rotational speed, the field weakening parameter is gradually decreased according to the step step.

2. The permanent magnet synchronous motor control method as described in claim 1, characterized in that, The field weakening control further includes: In response to the fact that the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is greater than the predetermined voltage and the desired rotational speed is greater than the current rotational speed, the field weakening parameter is increased, and In response to the fact that the magnitude of the voltage vector synthesized by the target d-axis voltage and the target q-axis voltage is less than or equal to the predetermined voltage, or the desired rotational speed is less than or equal to the current rotational speed, the field weakening parameter is reduced. The weak magnetic parameter is an angle ranging from the lower limit to the upper limit of the angle.

3. The permanent magnet synchronous motor control method as described in claim 1, characterized in that, The step size is an angle ranging from 0.05 degrees to 0.2 degrees.

4. The permanent magnet synchronous motor control method according to any one of claims 1-3, characterized in that, The field weakening parameter is the angle β between the current vector is output by the rotation speed ring and the q-axis, the d-axis reference current issinβ, and the q-axis reference current iscosβ.

5. The permanent magnet synchronous motor control method according to any one of claims 1-3, characterized in that, The predetermined voltage is μm, the target d-axis voltage is ud, and the adjusted q-axis voltage determined based on the predetermined voltage and the target d-axis voltage is μm². ud2.

6. The permanent magnet synchronous motor control method as described in claim 1, characterized in that, The predetermined voltage is the inverter's rated voltage.

7. A storage medium, characterized in that, The storage medium stores computer software instructions configured for the controller to execute the permanent magnet synchronous motor control method as described in any one of claims 1-6.

8. A control device for a permanent magnet synchronous motor, characterized in that, It includes a controller and a memory, the memory storing one or more programs configured to be executed by the controller as described in any one of claims 1-6.

9. An electronic device, characterized in that, It includes a permanent magnet synchronous motor, an inverter, and a permanent magnet synchronous motor control device as described in claim 8.

10. The electronic device as claimed in claim 9, characterized in that, The permanent magnet synchronous motor control device outputs a modulated PWM signal to the inverter so that the inverter outputs three-phase current to the stator winding of the permanent magnet synchronous motor.

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