Permanent magnet synchronous motor position sensorless control method and device, vehicle and medium

Abstract

This application relates to a sensorless control method, device, vehicle, and medium for a permanent magnet synchronous motor (PMSM). The method includes: acquiring a reference value of a high-frequency voltage signal injected via a high-frequency injection method when the motor enters a transition speed range; generating a virtual cancellation signal based on the reference value of the high-frequency voltage signal; canceling the virtual cancellation signal with a high-frequency interference signal generated by a model-based position observer; calculating a target rotor position and target rotor speed based on a first rotor position estimate and a first rotor speed estimate output by the model-based position observer after interference cancellation; and controlling the motor based on the target rotor position and target rotor speed. This solves the problems of single position estimation methods for PMSMs being unable to adapt to full-speed-range operation and the lack of smooth transition in traditional switching strategies, achieving high-precision, high-robustness, and smooth and stable operation of PMSMs across the entire speed range.

Description

Technical Field

[0001] This application relates to the field of permanent magnet synchronous motor control technology, and in particular to a sensorless control method, device, vehicle, and medium for a permanent magnet synchronous motor. Background Technology

[0002] Sensorless control technology for permanent magnet synchronous motors typically employs a composite control strategy to achieve full-speed-range operation: in the low-speed and zero-speed regions, a high-frequency signal injection method is used to estimate the rotor position using the salient pole effect of the motor; in the medium- and high-speed regions, a model-based position observer is used to estimate the rotor position based on the back electromotive force.

[0003] However, the two methods employed in the composite control strategy suffer from mutual interference when they coexist in the transition speed range. The high-frequency voltage signal injected into the motor windings by the high-frequency injection method can couple to the input of the model-based position observer through the electrical path, forming a high-frequency interference component inside the observer. This affects the accuracy of its position estimation, leading to an unsmooth transition process or even loss of synchronization. Summary of the Invention

[0004] This application provides a sensorless control method, device, vehicle, and medium for permanent magnet synchronous motors to solve the problems that single position estimation methods for permanent magnet synchronous motors cannot adapt to full-speed-range operation and that traditional switching strategies have unsmooth transitions. It achieves high-precision, high-robustness, and smooth and stable operation of permanent magnet synchronous motors across the entire speed range.

[0005] The first aspect of this application provides a sensorless control method for a permanent magnet synchronous motor, comprising the following steps: when the motor enters a preset transition speed range, acquiring a reference value of a high-frequency voltage signal injected by a high-frequency injection method, and generating a virtual cancellation signal based on the reference value of the high-frequency voltage signal; cancelling the virtual cancellation signal with a high-frequency interference signal generated by the high-frequency voltage signal in a model-based position observer; calculating a target rotor position and a target rotor speed based on a first rotor position estimate and a first rotor speed estimate output by the model-based position observer after interference cancellation, so as to control the motor according to the target rotor position and the target rotor speed.

[0006] Optionally, the calculation of the target rotor position and target rotor speed based on the first rotor position estimate and the first rotor speed estimate output by the model-based position observer after interference cancellation includes: acquiring the second rotor position estimate and the second rotor speed estimate output by the high-frequency injection method; in response to the motor speed being less than the lower limit speed threshold of the preset transition speed range, the target rotor position and target rotor speed are respectively the second rotor position estimate and the second rotor speed estimate; in response to the motor speed being greater than or equal to the lower limit speed threshold of the preset transition speed range and less than or equal to the upper limit speed threshold of the preset transition speed range, the target rotor position and target rotor speed are respectively the first rotor position estimate and the first rotor speed estimate.

[0007] Optionally, the virtual cancellation signal Represented as: ; in, For discrete sampling times, Let be the weight coefficient vector of the adaptive filter. The input high-frequency voltage signal vector.

[0008] Optionally, when cancelling the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal in the model-based position observer, the method includes: extracting the error signal of the internal phase-locked loop of the model-based position observer if there is an uncancelled high-frequency interference signal; performing narrowband bandpass filtering on the error signal at the angular frequency of the high-frequency voltage signal injected by the high-frequency injection method, retaining residual interference components with the same frequency as the high-frequency voltage signal injected by the high-frequency injection method; and updating the weight coefficients of the adaptive filter based on the residual interference components using the least mean square algorithm.

[0009] Optionally, the updated weight coefficients of the adaptive filter are: ; in, Step size factor This represents residual interference components.

[0010] Optionally, it further includes: when the target rotor position and the target rotor speed are switched from the first rotor position estimate and the first rotor speed estimate to the second rotor position estimate and the second rotor speed estimate, error compensation is performed on the first rotor position estimate output by the model method position observer.

[0011] Optionally, the error compensation method is as follows: ; in, This is the time elapsed since the switch. The decay time constant, This is the estimated first rotor position after error compensation. This is the second rotor position estimate output by the high-frequency injection method. The first rotor position estimate is output by the model-based position observer.

[0012] A second aspect of this application provides a sensorless control device for a permanent magnet synchronous motor, comprising: a signal generation module, configured to acquire a reference value of a high-frequency voltage signal injected by a high-frequency injection method when the motor enters a preset transition speed range, and generate a virtual cancellation signal based on the reference value of the high-frequency voltage signal; a cancellation module, configured to cancel the virtual cancellation signal with a high-frequency interference signal generated by the high-frequency voltage signal in a model-based position observer; and a control module, configured to calculate a target rotor position and a target rotor speed based on a first rotor position estimate and a first rotor speed estimate output by the model-based position observer after interference cancellation, so as to control the motor according to the target rotor position and the target rotor speed.

[0013] Optionally, the control module is further configured to: acquire the second rotor position estimate and the second rotor speed estimate output by the high-frequency injection method; in response to the motor speed being less than the lower limit speed threshold of the preset transition speed range, the target rotor position and the target rotor speed are respectively the second rotor position estimate and the second rotor speed estimate; in response to the motor speed being greater than or equal to the lower limit speed threshold of the preset transition speed range and less than or equal to the upper limit speed threshold of the preset transition speed range, the target rotor position and the target rotor speed are respectively the first rotor position estimate and the first rotor speed estimate.

[0014] Optionally, the virtual cancellation signal Represented as: ; in, For discrete sampling times, Let be the weight coefficient vector of the adaptive filter. The input high-frequency voltage signal vector.

[0015] Optionally, when cancelling the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal in the model-based position observer, the cancellation module is further configured to: extract the error signal of the phase-locked loop inside the model-based position observer if there is an uncancelled high-frequency interference signal; perform narrowband bandpass filtering on the error signal at the angular frequency of the high-frequency voltage signal injected by the high-frequency injection method, retaining residual interference components with the same frequency as the high-frequency voltage signal injected by the high-frequency injection method; and update the weight coefficients of the adaptive filter based on the residual interference components using the least mean square algorithm.

[0016] Optionally, the updated weight coefficients of the adaptive filter are: ; in, Step size factor This represents residual interference components.

[0017] Optionally, the permanent magnet synchronous motor sensorless control device further includes: when the target rotor position and the target rotor speed are switched from the first rotor position estimate and the first rotor speed estimate to the second rotor position estimate and the second rotor speed estimate, error compensation is performed on the first rotor position estimate output by the model method position observer.

[0018] Optionally, the error compensation method is as follows: ; in, This is the time elapsed since the switch. The decay time constant, This is the estimated first rotor position after error compensation. This is the second rotor position estimate output by the high-frequency injection method. The first rotor position estimate is output by the model-based position observer.

[0019] A third aspect of this application provides a vehicle, including: a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the program to implement the sensorless control method for a permanent magnet synchronous motor as described in the above embodiments.

[0020] A fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the sensorless control method for a permanent magnet synchronous motor as described in the above embodiments.

[0021] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0022] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart of a sensorless control method for a permanent magnet synchronous motor according to an embodiment of this application; Figure 2 This is a schematic diagram of the adaptive filter weight coefficient initialization process according to an embodiment of this application; Figure 3 This is a flowchart of a sensorless control method for a permanent magnet synchronous motor according to an embodiment of this application; Figure 4 This is an example diagram of a sensorless control device for a permanent magnet synchronous motor according to an embodiment of this application; Figure 5 This is a schematic diagram of a vehicle structure according to an embodiment of this application. Detailed Implementation

[0023] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0024] The following describes a sensorless control method, apparatus, vehicle, and medium for permanent magnet synchronous motors (PMSMs) according to embodiments of this application, with reference to the accompanying drawings. Addressing the issues mentioned in the background art, such as the inability of single-position estimation methods for PMSMs to adapt to full-speed-range operation and the lack of smooth transitions in traditional switching strategies, this application provides a sensorless control method for PMSMs. In this method, when the motor enters a preset transition speed range, a reference value of a high-frequency voltage signal injected using a high-frequency injection method is acquired, and a virtual cancellation signal is generated based on the reference value of the high-frequency voltage signal. The virtual cancellation signal is then used to cancel out the high-frequency interference signal generated by the high-frequency voltage signal in a model-based position observer. Based on the first rotor position estimate and the first rotor speed estimate output by the model-based position observer after interference cancellation, the target rotor position and target rotor speed are calculated, and the motor is controlled according to the target rotor position and target rotor speed. This solves the problems of the inability of single-position estimation methods for PMSMs to adapt to full-speed-range operation and the lack of smooth transitions in traditional switching strategies, achieving high-precision, high-robustness, and smooth and stable operation of PMSMs across the entire speed range.

[0025] Specifically, Figure 1 This is a schematic flowchart illustrating a sensorless control method for a permanent magnet synchronous motor provided in an embodiment of this application.

[0026] like Figure 1 As shown, the sensorless control method for the permanent magnet synchronous motor includes the following steps: In step S101, when the motor enters the preset transition speed range, a reference value of the high-frequency voltage signal injected by the high-frequency injection method is obtained, and a virtual cancellation signal is generated based on the reference value of the high-frequency voltage signal.

[0027] Optionally, in some embodiments, a virtual cancellation signal Represented as: ; in, For discrete sampling times, Let be the weight coefficient vector of the adaptive filter. The input high-frequency voltage signal vector.

[0028] The motor control system involved in this embodiment includes a permanent magnet synchronous motor, a current sensor, a controller (such as a DSP chip), and an inverter. The controller has an embedded sensorless control algorithm program.

[0029] Before starting the motor, first set the lower limit speed threshold of the transition speed range in the controller. and upper speed threshold Both are based on the actual speed of the motor. For reference, units are consistent. For example, for a motor with a rated speed of 3000 rpm, the following can be set: 300rpm The speed is 600 rpm. As the motor speed increases from zero, the rotor position is obtained and the motor operation is controlled using a high-frequency injection method. When the motor speed is detected... Entering this transition speed range (i.e.) and When the high-frequency voltage signal injected by the high-frequency injection method is obtained, a reference value is acquired, and a virtual cancellation signal is generated based on the reference value of the high-frequency voltage signal. Within the transition speed range, the original high-frequency injection method continues to operate, meaning the controller remains in the estimated rotating coordinate system. A high-frequency voltage signal is injected onto the shaft. Simultaneously, a model-based position observer (e.g., a sliding mode observer or a model reference adaptive system) is activated, enabling it to run in parallel and output rotor position estimates. and rotor speed estimate The high-frequency injection method continues to output its rotor position estimate. and rotor speed estimate .

[0030] First, a reference value for the high-frequency voltage signal is obtained. Inside the controller, the high-frequency injection module generates a known, clean reference value for the high-frequency voltage signal. This signal is typically a sine wave with known amplitude and frequency, and its expression is: ; in, For the injected voltage amplitude, The angular frequency of the injected signal, For time.

[0031] Secondly, the reference value of the high-frequency voltage signal Input to the adaptive filter.

[0032] This application sets up an adaptive filter. Its input is The output is a virtual cancellation signal. Adaptive filter Using a finite impulse response structure, its input-output relationship can be expressed as: ; in, For discrete sampling times, Let be the weight coefficient vector of the adaptive filter. The input signal vector (composed of the current and historical time points) (Composition). The order of the filter can be selected according to actual needs, such as 2nd or 4th order.

[0033] Adaptive Filter The goal is to make its output High-frequency interference signals actually generated at the input of the model method position observer, compared with high-frequency voltage signals. They are equal in amplitude but opposite in phase, that is... When this condition is met, the two can cancel each other out when superimposed at the observer input.

[0034] To achieve the above goals, the filter weight coefficients need to be adjusted in real time. This application employs the least mean square algorithm to adaptively update the weight coefficients. Therefore, an error signal reflecting the offsetting effect is needed.

[0035] In step S102, the virtual cancellation signal is canceled out with the high-frequency interference signal generated by the high-frequency voltage signal at the model method position observer.

[0036] Optionally, in some embodiments, when cancelling the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal in the model-based position observer, the method includes: extracting the error signal of the phase-locked loop inside the model-based position observer if there is an uncancelled high-frequency interference signal; performing narrowband bandpass filtering on the error signal at the angular frequency of the high-frequency voltage signal injected by the high-frequency injection method, retaining the residual interference component with the same frequency as the high-frequency voltage signal injected by the high-frequency injection method; and updating the weight coefficients of the adaptive filter based on the residual interference component using the least mean square algorithm.

[0037] Optionally, in some embodiments, the updated adaptive filter weights are: ; in, Step size factor This represents residual interference components.

[0038] Specifically, such as Figure 2 As shown, an error signal containing residual high-frequency interference is extracted from within the model-based position observer. A typical model-based position observer usually includes a phase-locked loop (PLL) for extracting rotor position information from the back electromotive force. The input error signal of this PLL is... (For example, based on back electromotive force in a synchronously rotating coordinate system) In the error signal constructed from the axis components, if there are uncancelled high-frequency interferences, it will contain interferences related to the injection frequency. The same ripple component.

[0039] Therefore, the input error signal of the phase-locked loop The signal is extracted and fed into a bandpass filter (BPF) for narrowband bandpass filtering. The center frequency of the BPF is set to the angular frequency of the high-frequency injected signal. The bandwidth setting is relatively narrow (e.g.) (Hz), to extract only the component with the same frequency as the injection frequency, the output of the BPF is the residual interference component. Its expression is: .

[0040] in, The magnitude directly reflects the virtual cancellation signal With actual interference The difference between them. If A value of zero indicates that the two have completely canceled each other out; if The non-zero value indicates the presence of uncancelled high-frequency interference signals, requiring further adjustment. .

[0041] Residual interference components The desired response of the adaptive filter is considered (ideally, its minimization). The least mean square algorithm is used to weight the coefficients of the adaptive filter. Perform iterative updates, such as: .in, The speed and stability of the weighting coefficient adjustment are controlled, thereby adjusting the virtual cancellation signal. .

[0042] To balance convergence speed and steady-state accuracy, this application adjusts the step size factor. Dynamic adjustments are made. Specifically, error signals are calculated in real time. The gradient vector can be approximated as . Its norm This is the magnitude of the vector. Step factor. Dynamically update the gradient norm using the following formula: ; in, and These are the preset maximum and minimum step sizes, This is a normalization constant. When the residual disturbance is large, the gradient norm is also large. The gradient norm is automatically increased to accelerate convergence; when residual disturbances are small, the gradient norm is small. Automatic reduction is used to ensure steady-state accuracy and avoid fluctuations in weighting coefficients.

[0043] Through the above adaptive process, the filter weight coefficients Continuous adjustments to improve output Gradually approaching the ideal value Ultimately, this results in residual interference components. Approaching zero.

[0044] The virtual cancellation signal generated by the adaptive filter Feedforward injection is performed at the input of the model-based position observer. The injection point is selected at a position in the observer that has not yet passed through a low-pass or integral stage. For example, for a sliding mode observer, the injection point can be... This is directly superimposed onto the current error term or back EMF term in the back EMF estimation equation. Thus, With actual interference The signals are directly added inside the observer to achieve cancellation. The virtual cancellation signal is injected and withdrawn in a gradual amplitude change manner, gradually increasing from zero to the target value or gradually decreasing to zero.

[0045] In step S103, the target rotor position and target rotor speed are calculated based on the first rotor position estimate and the first rotor speed estimate output by the model method position observer after interference cancellation, so as to control the motor according to the target rotor position and target rotor speed.

[0046] Optionally, in some embodiments, calculating the target rotor position and target rotor speed based on the first rotor position estimate and the first rotor speed estimate output by the model-based position observer after interference cancellation includes: acquiring the second rotor position estimate and the second rotor speed estimate output by the high-frequency injection method; responding to the motor speed being less than the lower limit speed threshold of a preset transition speed range, the target rotor position and target rotor speed are respectively the second rotor position estimate and the second rotor speed estimate; responding to the motor speed being greater than or equal to the lower limit speed threshold of the preset transition speed range and less than or equal to the upper limit speed threshold of the preset transition speed range, the target rotor position and target rotor speed are respectively the first rotor position estimate and the first rotor speed estimate.

[0047] After the above cancellation, the first rotor position estimate output by the model-based position observer is... and the estimated speed of the first rotor It is now almost unaffected by the high-frequency injection signal, and its accuracy is comparable to that during pure medium-to-high-speed operation. Meanwhile, the high-frequency injection method continues to output its second rotor position estimate. Second rotor speed estimate .

[0048] Within the transition speed range, the two are merged using a direct switching method: When the motor speed At that time, only the results of the high-frequency injection method, i.e., the target rotor position, were used. Target rotor speed .

[0049] When the motor speed and At that time, the model method position observer results, i.e., the target rotor position, are used. Target rotor speed .

[0050] The final target rotor position and target rotor speed It is used for coordinate transformation and speed loop feedback in motor vector control, generates drive signals for the inverter, and realizes closed-loop control of the motor.

[0051] Optionally, in some embodiments, the method further includes: when the target rotor position and target rotor speed are switched from a first rotor position estimate and a second rotor position estimate and a second rotor speed estimate, error compensation is performed on the first rotor position estimate output by the model-based position observer.

[0052] In some embodiments, the error compensation method is as follows: ; in, The decay time constant, This is the estimated first rotor position after error compensation. This is the second rotor position estimate output by the high-frequency injection method. This is the first rotor position estimate output by the model-based position observer. This is the time elapsed since the switch. This is the decay time constant (e.g., 0.01 seconds).

[0053] To eliminate the minute jumps that may occur at the moment of switching due to the inconsistency between the two estimates, a certain method is adopted in the first control cycle after the switching occurs. The first rotor position estimate output by the model-based position observer A one-time error compensation is performed, which causes the initial position error during switching to decay naturally according to an exponential law, achieving a smooth transition.

[0054] To enable those skilled in the art to further understand the sensorless control method for permanent magnet synchronous motors according to the embodiments of this application, the following detailed description is provided in conjunction with specific embodiments, such as... Figure 3 As shown.

[0055] S1. When the motor is operating in the transition speed range from low speed to high speed, continue to inject a high-frequency voltage signal into the motor windings; S2. Obtain a reference value for the high-frequency voltage signal, and generate a virtual cancellation signal based on the reference value to cancel the high-frequency interference signal generated by the high-frequency voltage signal at the input of the model method position observer. S3. Feed the virtual cancellation signal forward to the input of the model method position observer so that it cancels out the high-frequency interference signal inside the observer; S4. The rotor position estimate output by the canceled model method position observer is fused with the rotor position estimate output by the high frequency injection method to obtain the final target rotor position and target rotor speed. S5. Based on the final target rotor position and target rotor speed, obtain the inverter's drive control signal, and then control the motor.

[0056] In summary, the technical effects of this application are as follows: 1. During the transition speed range when the motor switches from low speed to high speed, the high-frequency injection signal remains unchanged. By generating a virtual cancellation signal, the high-frequency interference is actively canceled inside the model-based position observer, thus fundamentally solving the interference problem without sacrificing the estimation accuracy of the low-speed segment.

[0057] 2. Using the pure reference value of the high-frequency voltage signal as input, an adaptive filter generates a virtual cancellation signal with the same amplitude but opposite phase as the high-frequency interference signal in real time, thereby achieving active suppression of interference.

[0058] 3. Extract the phase-locked loop input error signal from the model-based position observer, and after bandpass filtering, obtain the residual interference component with the same frequency as the injection frequency. Use this component as the desired response of the adaptive filter to make the virtual cancellation signal continuously approximate the actual interference signal.

[0059] 4. The least mean square algorithm is used to update the weight coefficients of the adaptive filter, and the step size factor is dynamically adjusted according to the gradient vector norm of the residual interference component. When the residual interference is large, the step size is increased to speed up convergence, and when the residual interference is small, the step size is decreased to ensure steady-state accuracy, thus achieving a balance between convergence speed and steady-state accuracy.

[0060] 5. The virtual cancellation signal is injected and withdrawn in a gradual amplitude change manner, gradually increasing from zero to the target value or gradually decreasing to zero, to avoid disturbance to the observer caused by signal abrupt changes and to ensure the smoothness of the transition process.

[0061] 6. A direct switching method is adopted to fuse the two position estimation results, and the position error is compensated exponentially at the moment of switching to achieve a smooth transition between intervals.

[0062] According to the sensorless control method for permanent magnet synchronous motors proposed in this application, when the motor enters a preset transition speed range, a reference value of the high-frequency voltage signal injected by the high-frequency injection method is obtained, and a virtual cancellation signal is generated based on the reference value of the high-frequency voltage signal. The virtual cancellation signal is then canceled out with the high-frequency interference signal generated by the model-based position observer. Based on the first rotor position estimate and the first rotor speed estimate output by the model-based position observer after interference cancellation, the target rotor position and target rotor speed are calculated, and the motor is controlled according to the target rotor position and target rotor speed. This solves the problems that the single position estimation method for permanent magnet synchronous motors cannot adapt to full-speed-range operation and that traditional switching strategies have unsmooth transitions, achieving high-precision, high-robustness, and smooth and stable operation of permanent magnet synchronous motors across the entire speed range.

[0063] Next, with reference to the accompanying drawings, a sensorless control device for a permanent magnet synchronous motor according to an embodiment of this application is described.

[0064] Figure 4 This is a block diagram of a sensorless control device for a permanent magnet synchronous motor according to an embodiment of this application.

[0065] like Figure 4As shown, the sensorless control device 10 for the permanent magnet synchronous motor includes: a signal generation module 100, a cancellation module 200, and a control module 300.

[0066] The signal generation module 100 is used to acquire the reference value of the high-frequency voltage signal injected by the high-frequency injection method when the motor enters the preset transition speed range, and generate a virtual cancellation signal based on the reference value of the high-frequency voltage signal; the cancellation module 200 is used to cancel the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal in the model method position observer; the control module 300 is used to calculate the target rotor position and target rotor speed based on the first rotor position estimate and the first rotor speed estimate output by the model method position observer after interference cancellation, so as to control the motor according to the target rotor position and target rotor speed.

[0067] Optionally, in some embodiments, the control module 300 is further configured to: acquire the second rotor position estimate and the second rotor speed estimate output by the high-frequency injection method; in response to the motor speed being less than the lower limit speed threshold of a preset transition speed range, the target rotor position and the target rotor speed are respectively the second rotor position estimate and the second rotor speed estimate; in response to the motor speed being greater than or equal to the lower limit speed threshold of the preset transition speed range and less than or equal to the upper limit speed threshold of the preset transition speed range, the target rotor position and the target rotor speed are respectively the first rotor position estimate and the first rotor speed estimate.

[0068] Optionally, in some embodiments, a virtual cancellation signal Represented as: ; in, For discrete sampling times, Let be the weight coefficient vector of the adaptive filter. The input high-frequency voltage signal vector.

[0069] Optionally, in some embodiments, when cancelling the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal in the model-based position observer, the cancellation module is further configured to: extract the error signal of the phase-locked loop inside the model-based position observer if there is an uncancelled high-frequency interference signal; perform narrowband bandpass filtering on the angular frequency of the high-frequency voltage signal injected by the high-frequency injection method on the error signal, retaining the residual interference component with the same frequency as the high-frequency voltage signal injected by the high-frequency injection method; and update the weight coefficients of the adaptive filter based on the residual interference component using the least mean square algorithm.

[0070] Optionally, in some embodiments, the updated adaptive filter weights are: ; in, Step size factor This represents residual interference components.

[0071] Optionally, the permanent magnet synchronous motor sensorless control device 10 further includes: when the target rotor position and target rotor speed are switched from the first rotor position estimate and the first rotor speed estimate to the second rotor position estimate and the second rotor speed estimate, error compensation is performed on the first rotor position estimate output by the model method position observer.

[0072] Optionally, in some embodiments, the error compensation method is as follows: ; in, This is the time elapsed since the switch. The decay time constant, This is the estimated first rotor position after error compensation. This is the second rotor position estimate output by the high-frequency injection method. This is the first rotor position estimate output by the model-based position observer.

[0073] It should be noted that the foregoing explanation of the sensorless control method for permanent magnet synchronous motors also applies to the sensorless control device for permanent magnet synchronous motors in this embodiment, and will not be repeated here.

[0074] According to the sensorless control device for permanent magnet synchronous motors proposed in this application, when the motor enters a preset transition speed range, a reference value of the high-frequency voltage signal injected by the high-frequency injection method is acquired, and a virtual cancellation signal is generated based on the reference value of the high-frequency voltage signal. The virtual cancellation signal is then canceled out with the high-frequency interference signal generated by the model-based position observer. Based on the first rotor position estimate and the first rotor speed estimate output by the model-based position observer after interference cancellation, the target rotor position and target rotor speed are calculated, and the motor is controlled according to the target rotor position and target rotor speed. This solves the problems that the single position estimation method for permanent magnet synchronous motors cannot adapt to full-speed-range operation, and that traditional switching strategies suffer from unsmooth transitions, achieving high-precision, high-robustness, and smooth and stable operation of permanent magnet synchronous motors across the entire speed range.

[0075] Figure 5 A schematic diagram of the structure of a vehicle provided in an embodiment of this application. The vehicle may include: The memory 501, the processor 502, and the computer program stored in the memory 501 and capable of running on the processor 502.

[0076] When the processor 502 executes the program, it implements the sensorless control device for permanent magnet synchronous motors provided in the above embodiments.

[0077] Furthermore, the vehicle also includes: Communication interface 503 is used for communication between memory 501 and processor 502.

[0078] The memory 501 is used to store computer programs that can run on the processor 502.

[0079] Memory 501 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0080] If the memory 501, processor 502, and communication interface 503 are implemented independently, then the communication interface 503, memory 501, and processor 502 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 5 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0081] Optionally, in a specific implementation, if the memory 501, processor 502, and communication interface 503 are integrated on a single chip, then the memory 501, processor 502, and communication interface 503 can communicate with each other through an internal interface.

[0082] Processor 502 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0083] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described sensorless control method for a permanent magnet synchronous motor.

[0084] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0085] Furthermore, 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 at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0086] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0087] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable storage medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable storage medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable storage medium could be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0088] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0089] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0090] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0091] The computer-readable storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A position sensorless control method of a permanent magnet synchronous motor, characterized by, Includes the following steps: When the motor enters the preset transition speed range, a reference value of the high-frequency voltage signal injected by the high-frequency injection method is obtained, and a virtual cancellation signal is generated based on the reference value of the high-frequency voltage signal. The virtual cancellation signal is canceled out with the high-frequency interference signal generated by the high-frequency voltage signal at the model-based position observer. The target rotor position and target rotor speed are calculated based on the first rotor position estimate and the first rotor speed estimate output by the model method position observer after interference cancellation, so as to control the motor according to the target rotor position and the target rotor speed.

2. The method of claim 1, wherein, The calculation of the target rotor position and target rotor velocity based on the first rotor position estimate and the first rotor velocity estimate output by the model-based position observer after interference cancellation includes: The estimated second rotor position and estimated second rotor speed output by the high-frequency injection method are collected. In response to the motor speed being less than the lower limit speed threshold of the preset transition speed range, the target rotor position and the target rotor speed are respectively the estimated value of the second rotor position and the estimated value of the second rotor speed; In response to the motor speed being greater than or equal to the lower limit speed threshold of the preset transition speed range and less than or equal to the upper limit speed threshold of the preset transition speed range, the target rotor position and the target rotor speed are respectively the first rotor position estimate and the first rotor speed estimate.

3. The method of claim 1, wherein, The virtual cancellation signal is represented as: ； wherein, is a discrete sampling instant, is a weight vector of the adaptive filter, is a vector of input high frequency voltage signals.

4. The method of claim 3, wherein, When cancelling the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal at the model-based position observer, the process includes: In the presence of uncancelled high-frequency interference signals, the error signal of the internal phase-locked loop of the model-based position observer is extracted; The error signal is subjected to narrowband bandpass filtering at the angular frequency of the high-frequency voltage signal injected by the high-frequency injection method, retaining residual interference components with the same frequency as the high-frequency voltage signal injected by the high-frequency injection method; The weight coefficients of the adaptive filter are updated using the least mean square algorithm based on the residual interference components.

5. The method of claim 4, wherein, The updated adaptive filter weights are: ； in, Step size factor This represents residual interference components.

6. The method of claim 2, wherein, Also includes: When the target rotor position and the target rotor speed are switched from the first rotor position estimate and the first rotor speed estimate to the second rotor position estimate and the second rotor speed estimate, error compensation is performed on the first rotor position estimate output by the model method position observer.

7. The method of claim 6, wherein, The error compensation method is as follows: ； in, This is the time elapsed since the switch. The decay time constant, This is the estimated first rotor position after error compensation. This is the second rotor position estimate output by the high-frequency injection method. This is the first rotor position estimate output by the model-based position observer.

8. A position sensorless control device for a permanent magnet synchronous motor, characterized by, include: The signal generation module is used to obtain a reference value of the high-frequency voltage signal injected by the high-frequency injection method when the motor enters the preset transition speed range, and generate a virtual cancellation signal based on the reference value of the high-frequency voltage signal. The cancellation module is used to cancel the virtual cancellation signal with the high-frequency interference signal generated by the high-frequency voltage signal at the model method position observer; The control module is used to calculate the target rotor position and target rotor speed based on the first rotor position estimate and the first rotor speed estimate output by the model method position observer after interference cancellation, so as to control the motor according to the target rotor position and the target rotor speed.

9. A vehicle, characterized in that, The method includes 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 sensorless control method for a permanent magnet synchronous motor as described in any one of claims 1-7.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the sensorless control method for a permanent magnet synchronous motor as described in any one of claims 1-7.

Images