Motor state estimation method, motor controller and electric drive assembly

Abstract

The application provides a motor state estimation method, a motor controller and an electric drive assembly, and relates to the technical field of motors.The motor state estimation method comprises the following steps: determining a current error according to a current observation value and a current feedback value of a motor, performing closed-loop control according to the current error to determine a back electromotive force deviation, and performing closed-loop control according to the back electromotive force deviation to determine a rotor speed and a position angle of the motor.Through the establishment of a current error feedback adjustment mechanism, the back electromotive force observation is more robust, the rotor speed and the angle are further controlled by using the back electromotive force deviation, the system state is indirectly deduced through the system output error, the closed-loop estimation mechanism is formed, the estimation value can be continuously corrected through the error negative feedback mechanism, the field orientation is more accurate, the high-speed control without a position sensor is realized, and the control performance, stability and dynamic response capability of the motor under high-speed or variable load conditions are improved.

Description

Technical Field

[0001] This invention relates to the field of electric drive technology for new energy vehicles, and more specifically, to a method for estimating motor status, a motor controller, and an electric drive assembly. Background Technology

[0002] With the rapid development of the automotive industry, the performance requirements for drive motor control systems are increasing. These systems not only need high efficiency, high responsiveness, and high stability, but also must adapt to complex operating conditions such as high speed and high load. Traditional permanent magnet synchronous motor control systems typically rely on position sensors to obtain rotor position and speed information. However, position sensors not only increase system cost and size, but their installation and use are also susceptible to environmental interference, especially under conditions of high temperature and high vibration, where stability is poor. Furthermore, sensor accuracy errors can lead to inaccurate motor torque control, affecting overall vehicle performance.

[0003] In related technologies, sensorless motor control methods are commonly used. For example, sensorless control methods in the high-speed range typically employ open-loop flux estimation and model reference adaptive methods. Open-loop flux estimation is greatly affected by motor parameters, and the system is prone to zero-drift interference of the signal, which affects the accuracy of speed estimation. On the other hand, the model reference adaptive method has weak load-carrying capacity and is difficult to adapt to the external characteristic requirements of the high-speed range. Summary of the Invention

[0004] The problem solved by this invention is how to achieve high-speed control of a motor.

[0005] To address the above problems, the present invention provides a method for estimating motor state, a motor controller, and an electric drive assembly.

[0006] In a first aspect, the present invention provides a method for estimating the state of a motor, comprising: The current error is determined based on the observed current value and current feedback value of the motor, and closed-loop control is performed based on the current error to determine the back electromotive force deviation. Closed-loop control is performed based on the back electromotive force deviation to determine the rotor speed and position angle of the motor.

[0007] Optionally, determining the current error based on the observed current value and the current feedback value of the motor includes: The observed current value is determined based on the stator dynamic voltage and stator static voltage; The current feedback value is determined based on the stator current during motor operation; The current error is determined based on the difference between the observed current value and the current feedback value.

[0008] Optionally, the step of performing closed-loop control based on the current error to determine the back electromotive force deviation includes: Construct an observer, wherein the observer adopts a PI control structure; The current error is input into the observer for closed-loop control. When the current error is zero, the back electromotive force deviation is output through the observer.

[0009] Optionally, inputting the current error into the observer for closed-loop control includes: The back EMF deviation is determined based on the current error. The ratio of the back EMF deviation to the inductance is integrated. The current observation value is updated based on the integration result. The current error is re-determined based on the updated current observation value and input into the observer for closed-loop control until the current error is zero.

[0010] Optionally, the step of determining the rotor speed and position angle of the motor by performing closed-loop control based on the back electromotive force deviation includes: Construct an angle estimation regulator, wherein the angle estimation regulator adopts a PI control structure; The back EMF deviation is input into the angle estimation regulator for closed-loop control. When the back EMF deviation is zero, the rotor speed and the position angle are output through the angle estimation regulator.

[0011] Optionally, inputting the back electromotive force deviation into the angle estimation regulator for closed-loop control includes: The rotor speed is determined based on the back EMF deviation. The rotor speed is integrated, and the position angle is determined based on the integration result. The back EMF deviation is re-determined based on the position angle and input into the angle estimation regulator for closed-loop control until the back EMF deviation is zero.

[0012] Optionally, the closed-loop control of the back EMF deviation is executed in the controller interrupt procedure before the closed-loop control of the rotor speed and the position angle.

[0013] In a second aspect, the present invention provides a motor controller, comprising: The first module is used to determine the current error based on the observed current value and the current feedback value of the motor, and to perform closed-loop control based on the current error to determine the back electromotive force deviation. The second module is used to perform closed-loop control based on the back electromotive force deviation to determine the rotor speed and position angle of the motor.

[0014] Thirdly, the present invention provides an electric drive assembly including a motor and a motor controller as described in the third aspect.

[0015] Fourthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the motor state estimation method as described in the first aspect.

[0016] The beneficial effects of the motor state estimation method of the present invention are as follows: by establishing a current error feedback adjustment mechanism, the back EMF observation becomes more robust, and the back EMF deviation is further used to control the speed and angle. The system state is indirectly derived through the system output error, forming a closed-loop estimation mechanism. The estimated value can be continuously corrected through the error negative feedback mechanism, making the magnetic field orientation more accurate. This achieves high-speed control without position sensors and improves the control performance, stability and dynamic response capability of the motor under high speed or variable load conditions. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the motor state estimation method according to an embodiment of the present invention; Figure 2 For the purposes of embodiments of the present invention to indicate The motor system control block diagram; Figure 3 The input for this embodiment of the invention is The output is The system control block diagram; Figure 4 This is a block diagram of the observer control according to an embodiment of the present invention; Figure 5 Embodiments of the present invention Control block diagram of the shaft back EMF observer; Figure 6 After ignoring the effect of the delay element in the embodiments of the present invention Control block diagram of the shaft back EMF observer; Figure 7 Based on the embodiments of the present invention Complete block diagram of sensorless angle estimation closed-loop control for shaft back EMF deviation; Figure 8 Based on the embodiments of the present invention Sensorless angle estimation closed-loop control block diagram for shaft back electromotive force deviation; Figure 9 This is a schematic diagram of the process for determining current error according to an embodiment of the present invention; Figure 10 This is a schematic diagram of the process for determining the back electromotive force deviation according to an embodiment of the present invention; Figure 11 This is a flowchart illustrating the process of determining the rotor speed and position angle of a motor according to an embodiment of the present invention. Figure 12This is a system architecture diagram of the motor controller according to an embodiment of the present invention; Figure 13 This is a system architecture diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0018] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the accompanying drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0019] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0020] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to"; the term "based on" means "at least partially based on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; and the term "optionally" means "optional embodiments". Definitions of other terms will be given in the following description. It should be noted that the concepts of "first," "second," etc., mentioned in this invention are used only to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0021] It should be noted that the terms "one" and "more" used in this invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0022] The names of the messages or information exchanged between the multiple devices in the embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of these messages or information.

[0023] like Figure 1 As shown in the figure, an embodiment of the present invention provides a motor state estimation method, including: S100: Determine the current error based on the observed current value and current feedback value of the motor, and perform closed-loop control based on the current error to determine the back electromotive force deviation.

[0024] Specifically, in combination Figure 5 , 6 As shown, based on the observed current values ​​of the motor (Estimated current) and current feedback value (Actual current) Determine current error According to the current error Closed-loop control can be implemented, for example, by adjusting a PI controller based on the current error, thereby determining the back electromotive force deviation. .

[0025] S200: Closed-loop control is performed based on the back electromotive force deviation to determine the rotor speed and position angle of the motor.

[0026] Specifically, in combination Figure 7 , 8 As shown, based on the back electromotive force deviation Closed-loop control is performed to determine the motor's rotor speed (rotor electrical angular frequency). ) and position angle (rotor electrical angle) ).

[0027] The principle of this invention is as follows: Under rotor magnetic field-oriented vector control conditions, the stator phase voltage equation of a permanent magnet synchronous motor can be expressed as: ; ; in, Stator phase voltage Axial components, Stator phase voltage Axial components, Stator current Axial components, Stator current Axial components, for Shaft inductor, for Shaft inductor, For stator resistance, It is a permanent magnet flux linkage. To synchronize the rotational angular frequency, It is a differential operator; Combination Figure 2 As shown, based on The axis voltage equation is expressed using Laplace's equation. The shaft stator current can be obtained as follows: ; in, For the Laplace operator.

[0028] Under steady-state conditions, with a differential term of 0, the stator phase voltage equation of the permanent magnet synchronous motor can be expressed as: ; ; Define the stator phase voltage under steady-state conditions as the static voltage, and let: ; ; in, For stator Shaft static voltage, For stator Shaft static voltage: ; When the rotor magnetic field orientation has an angular deviation At that time, the stator phase voltage equation of the permanent magnet synchronous motor can be characterized as: ; ; in, There is an angular deviation in the orientation of the rotor magnetic field. time Shaft back electromotive force deviation, There is an angular deviation in the orientation of the rotor magnetic field. time Shaft back electromotive force deviation; Define the stator phase voltage under the condition of angular deviation in rotor magnetic field orientation as the dynamic voltage, let: ; ; in, For stator Shaft dynamic voltage, For stator Shaft dynamic voltage; The difference between the dynamic and static phase voltages of the stator of a permanent magnet synchronous motor can be expressed as: ; ; This can be achieved through the stator phase voltage. Shaft dynamic voltage and Estimate the stator voltage by the difference in shaft static voltage shaft current, i.e.: ; in, Stator current Shaft component estimation values; Combination Figure 3 As shown, assuming the rotor magnetic field is accurately oriented, Shaft back electromotive force deviation Then estimate the stator The shaft current is: ; in, Stator current The estimated value of the shaft component, i.e. the current observation value; The observer method can be used to... Shaft back electromotive force deviation Observations are performed. Observers typically use adjustable models and reference models to approximate state variables; in this case, a motor is used. The shaft current detection model is the reference model, and the motor... The shaft current estimation model is an adjustable model, and the design... Regulator to achieve Shaft back electromotive force deviation Observations.

[0029] Combination Figure 4 As shown (the diagonal arrow points from below to the adjustable model box, indicating that the model parameters are adjustable, and the direction is correct), ignore. Shaft back electromotive force deviation The feedforward term in the observer control block diagram, considering system delay, yields the following: Figure 5 shown Quantitative control block diagram of the shaft back EMF observer, in Figure 5 middle, For observer The transfer function of the regulator, Due to sampling delay and The transfer function of the delay element that causes the delay. For the transfer function of the control object, For observer The proportional element parameters of the regulator, For observer Integral time parameter of the integral element of the regulator.

[0030] Among them, delay time and Cycle time Basically the same, that is Therefore, the delay element can be approximated as a first-order inertial element, that is: ; in, For the delay time, for Cycle time.

[0031] Combination Figure 6 As shown, to simplify the design of control parameters, the effect of the delay element can be ignored for the time being.

[0032] The open-loop transfer function of the observer is: ; The observer's closed-loop transfer function is: ; For now, we will disregard the zeros of the closed-loop transfer function and only consider its poles, that is, treat the numerator of the transfer function as... Then, the transfer function of the closed-loop transfer function can be written as the standard second-order system transfer function as follows: ; in, The overshoot-related variables are the overshoot of the standard second-order system transfer function of the observer. For the cutoff frequency related variables of the standard second-order system transfer function of the observer; Using the principle that the coefficients of corresponding terms are equal, we get: ; ; Design and You can design Figure 6 middle Regulator control parameters and .

[0033] To achieve a balance between fast response and stability in the observer control system, the mid-frequency bandwidth is... ,but: ; To ensure that the overshoot of the control system does not exceed the limit, the overshoot-related variables of the standard second-order system transfer function are set to... ,but: ; in, for Cycle time, for Periodic frequency; for The deviation of the shaft back electromotive force, and the deviation angle of the magnetic field orientation. The quantitative relationship can be represented as follows:

[0034] When the rotor magnetic field orientation deviation is small, that is hour, .then, The shaft back electromotive force deviation can be characterized as: ; Combination Figure 7 As shown, it can be controlled The position of the permanent magnet in the magnetic field is estimated by the back electromotive force deviation of the shaft being 0, that is, the angle estimation without position sensor is realized.

[0035] Due to the lack of position sensor angle estimation delay time and back EMF observer time The results are basically the same, so the loop delay time is estimated using the angle without position sensors. Similarly, this delay element can be approximated as a first-order inertial element, that is: ; Combination Figure 8 As shown, to simplify the design of control parameters, the effect of the delay element is not considered for the time being.

[0036] The transfer function of the feedforward channel of the sensorless angle estimation closed-loop control loop is: ; in, For angle estimation loop The transfer function of the regulator, Let be the transfer function of the integral element. For angle estimation loop The proportional element parameters of the regulator, For angle estimation loop Integral time parameter of the integral element of the regulator.

[0037] The transfer function of the feedback channel of the sensorless angle estimation closed-loop control circuit is: ; The closed-loop transfer function of the sensorless angle estimation closed-loop control loop is: ; make Then the closed-loop transfer function can be expressed as: ; in, Equivalent gain of the feedback channel in the closed-loop control loop for angle estimation without position sensors; For now, we will disregard the zeros of the closed-loop transfer function and only consider its poles, that is, treat the numerator of the transfer function as... Then, the transfer function of the denominator of the closed-loop transfer function can be written as the transfer function of a standard second-order system as follows: ; in, To estimate the overshoot related variables of the transfer function of a closed-loop standard second-order system from an angle perspective, The cutoff frequency related variables are used to estimate the transfer function of a closed-loop standard second-order system from an angle perspective; Using the principle that the coefficients of corresponding terms are equal, we get: ; ; Design and You can design Figure 7 , 8 In Regulator control parameters and .

[0038] To achieve a balance between fast response and stability in the sensorless angle estimation control system, the mid-bandwidth of the sensorless angle estimation system should be optimized. ,but: ; in, To estimate the cutoff frequency related variables of the transfer function of a closed-loop standard second-order system from an angle perspective, For the cutoff frequency related variables of the standard second-order system transfer function of the observer; To ensure that the overshoot of the control system does not exceed the limit, the coefficients of the quadratic term of the standard second-order system are set... ,but: ; because Therefore, the angle estimation system without position sensors The regulator parameters are designed as follows: ; ; In the software implementation, both the back EMF observer closed-loop control program and the sensorless angle closed-loop control program need to be set in... In the interrupt routine, the interrupt frequency is set to The generation frequency is typically 10. ,Right now , Furthermore, the back EMF observer closed-loop control needs to be executed first in the interrupt routine, while the sensorless angle closed-loop control is executed later.

[0039] In this embodiment, by establishing a current error feedback adjustment mechanism, the back EMF observation becomes more robust. The back EMF deviation is further used to control the speed and angle. The system state is indirectly derived through the system output error, forming a closed-loop estimation mechanism. The estimated value can be continuously corrected through the error negative feedback mechanism, making the magnetic field orientation more accurate. This achieves high-speed control without position sensors and improves the control performance, stability, and dynamic response capability of the motor under high-speed or variable load conditions.

[0040] Optionally, determining the current error based on the observed current value and the current feedback value of the motor includes: S110: Determine the current observation value based on the stator dynamic voltage and stator static voltage.

[0041] Specifically, in combination Figure 9 As shown, the stator phase voltage can be... Axial components Input to such Figure 3 The system control block diagram shown indicates that the stator phase voltage can be determined. Shaft dynamic voltage and Difference in shaft static voltage Determine current observations .

[0042] S120: Determine the current feedback value based on the stator current during motor operation.

[0043] Specifically, in combination Figure 9 As shown, the three-phase stator current signal is collected during motor operation and transformed into a stationary coordinate system to determine the current feedback value. .

[0044] S130: Determine the current error based on the difference between the observed current value and the current feedback value.

[0045] Specifically, in combination Figure 9 As shown, the current observation values and current feedback value Input to such Figure 5 The current error is obtained from the control block diagram shown.

[0046] In this optional embodiment, by clearly distinguishing the acquisition methods of "current observation value" and "current feedback value"—which come from the stator voltage model and actual current sampling respectively—a more accurate current error criterion is established, improving the accuracy and robustness of the observer control and providing a more accurate input basis for subsequent adjustment of back EMF deviation.

[0047] Optionally, the step of performing closed-loop control based on the current error to determine the back electromotive force deviation includes: S140: Construct an observer, wherein the observer adopts a PI control structure.

[0048] Specifically, in combination Figure 10 As shown, an observer is constructed, which adopts a PI control structure, that is, a proportional-integral closed-loop control.

[0049] S150: Input the current error into the observer for closed-loop control. When the current error is zero, output the back electromotive force deviation through the observer.

[0050] Specifically, in combination Figure 10 As shown, the current error is input into the observer for closed-loop control. When the current error converges to zero, the output back electromotive force deviation can accurately characterize the degree of deviation of the rotor magnetic field direction, providing a core basis for subsequent angle estimation.

[0051] In this optional embodiment, the current error adjustment process is normalized into a PI control structure, so that the back EMF deviation can be dynamically adjusted under closed-loop conditions and approach a stable value, taking into account both fast response and steady-state error suppression.

[0052] Optionally, inputting the current error into the observer for closed-loop control includes: The back EMF deviation is determined based on the current error. The ratio of the back EMF deviation to the inductance is integrated. The current observation value is updated based on the integration result. The current error is re-determined based on the updated current observation value and input into the observer for closed-loop control until the current error is zero.

[0053] Specifically, based on the control law expression of the observer, the back EMF deviation can be determined according to the current error. The back EMF deviation is used to correct the observer model. For example, the back EMF deviation is divided by the inductance constant of the motor stator to obtain its influence on the current change per unit time. The result is integrated, and the current observation value is updated according to the integration result. The current error is re-determined according to the updated current observation value and input into the observer for closed-loop control. The above process is repeated until the current error is zero, so that the estimated current gradually approaches the real current, thereby improving the estimation accuracy of the observer.

[0054] In this optional embodiment, the current observation is updated by integrating the back EMF deviation with the inductance ratio, and the current error is reconstructed, thereby achieving feedback-based dynamic convergence. This effectively resists parameter disturbances and model uncertainties, enabling the observer to maintain high-precision tracking throughout the operation.

[0055] Optionally, the step of determining the rotor speed and position angle of the motor by performing closed-loop control based on the back electromotive force deviation includes: S210: Construct an angle estimation regulator, wherein the angle estimation regulator adopts a PI control structure.

[0056] Specifically, in combination Figure 11 As shown, an angle estimation regulator is constructed. The angle estimation regulator adopts a PI control structure, that is, it uses proportional-integral closed-loop control.

[0057] S220: The back EMF deviation is input to the angle estimation regulator for closed-loop control. When the back EMF deviation is zero, the rotor speed and the position angle are output through the angle estimation regulator.

[0058] Specifically, in combination Figure 11 As shown, the back electromotive force deviation (representing the error in the current magnetic field direction estimation) is input into the angle estimation regulator for closed-loop control. When the back electromotive force deviation is zero, it indicates that the magnetic field orientation is accurate, and automatic correction of the magnetic field direction can be achieved. The rotor speed and position angle are output through the angle estimation regulator, achieving high-precision position and speed estimation without the need for position sensors.

[0059] In this optional embodiment, by establishing an angle estimation closed-loop controller and using PI control to adjust the back EMF deviation, dynamic estimation of rotor speed and position angle is achieved. It does not rely on mechanical position sensors. The angle adjuster is driven by the back EMF error, which can quickly converge to the actual magnetic field direction, and has the advantages of high precision and high response.

[0060] Optionally, inputting the back electromotive force deviation into the angle estimation regulator for closed-loop control includes: The rotor speed is determined based on the back EMF deviation. The rotor speed is integrated, and the position angle is determined based on the integration result. The back EMF deviation is re-determined based on the position angle and input into the angle estimation regulator for closed-loop control until the back EMF deviation is zero.

[0061] Specifically, in combination Figure 7 , 8 As shown, the control law expression of the angle estimation regulator can determine the rotor speed (rotor electrical angular frequency) based on the back electromotive force deviation. The rotor electrical angular frequency is processed by an integrator to obtain the motor's position angle (rotor electrical angle). The electric angle feedback is used for coordinate transformation and control of the next cycle. It affects the orientation of the magnetic field, which reduces the back electromotive force deviation in the next cycle. The system iterates continuously until it stabilizes.

[0062] In this optional embodiment, the entire angle estimation process is refined. The electric angular frequency is generated from the back electromotive force deviation, then the electric angle is generated by integration, and the deviation is corrected in reverse. This realizes a complete closed-loop iterative process, effectively avoiding angle drift and cumulative error problems. Even without position sensors, the angle estimation stability and accuracy can be maintained for long-term operation.

[0063] Optionally, the closed-loop control of the back EMF deviation is executed in the controller interrupt procedure before the closed-loop control of the rotor speed and the position angle.

[0064] Specifically, in each interruption cycle, closed-loop control of the current error is executed first to determine the back EMF deviation, and then closed-loop control of the back EMF deviation is executed to determine the rotor speed and position angle.

[0065] In this optional embodiment, by setting the observer control to take precedence over the angle control in the interrupt routine, the execution order of the controller is clarified, which effectively ensures the timeliness and stability of the data dependency chain, improves system stability, and prevents estimation errors caused by misalignment of control links.

[0066] like Figure 12 As shown, an embodiment of the present invention provides a motor controller 1200, comprising: The first module 1210 is used to determine the current error based on the observed current value and the current feedback value of the motor, and to perform closed-loop control based on the current error to determine the back electromotive force deviation. The second module 1220 is used to perform closed-loop control based on the back electromotive force deviation to determine the rotor speed and position angle of the motor.

[0067] like Figure 13 As shown, an electronic device 1300 provided in this embodiment of the invention includes a memory 1320 and a processor 1310; the memory 1320 is used to store a computer program; the processor 1310 is used to implement the motor state estimation method as described above when the computer program is executed.

[0068] Alternatively, an electronic device 1300 includes a memory 1320 and a processor 1310 coupled to the memory 1320; the memory 1320 is configured to store a computer program; and the processor 1310 is configured to perform the following operations when the computer program is executed: The current error is determined based on the observed current value and current feedback value of the motor, and closed-loop control is performed based on the current error to determine the back electromotive force deviation. Closed-loop control is performed based on the back electromotive force deviation to determine the rotor speed and position angle of the motor.

[0069] An electric drive assembly provided in this embodiment of the invention includes a motor and a motor controller as described above.

[0070] This invention provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the motor state estimation method described above.

[0071] Alternatively, a non-volatile computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to perform the following operations: The current error is determined based on the observed current value and current feedback value of the motor, and closed-loop control is performed based on the current error to determine the back electromotive force deviation. Closed-loop control is performed based on the back electromotive force deviation to determine the rotor speed and position angle of the motor.

[0072] Electronic device 1300, which can serve as a server or client of the present invention, is described below as an example of a hardware device applicable to various aspects of the present invention. Electronic device 1300 is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic device 1300 can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0073] Electronic device 1300 includes a computing unit that can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) or a computer program loaded from a storage unit into random access memory (RAM). The RAM may also store various programs and data required for device operation. The computing unit, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0074] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc. In this application, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments of the present invention according to actual needs. Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units can be implemented in hardware or as software functional units.

[0075] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A method for estimating the state of a motor, characterized in that, include: The current error is determined based on the observed current value and the current feedback value of the motor, and the current error is input into the PI control structure for closed-loop control to determine the back electromotive force deviation. The back EMF deviation is input into a PI control structure for closed-loop control to determine the rotor speed and position angle of the motor. The determination of current error based on the observed current value and current feedback value of the motor includes: The observed current value is determined based on the stator dynamic voltage and the stator static voltage. The stator dynamic voltage is the stator phase voltage under the condition that the rotor magnetic field orientation has an angular deviation, and the stator static voltage is the stator phase voltage under the steady-state condition. The current feedback value is determined based on the stator current during motor operation; The current error is determined based on the difference between the observed current value and the current feedback value.

2. The motor state estimation method according to claim 1, characterized in that, The step of inputting the current error into the PI control structure for closed-loop control to determine the back electromotive force deviation includes: Construct an observer, wherein the observer adopts a PI control structure; The current error is input into the observer for closed-loop control. When the current error is zero, the back electromotive force deviation is output through the observer.

3. The motor state estimation method according to claim 2, characterized in that, The step of inputting the current error into the observer for closed-loop control includes: The back EMF deviation is determined based on the current error. The ratio of the back EMF deviation to the inductance is integrated. The current observation value is updated based on the integration result. The current error is re-determined based on the updated current observation value and input into the observer for closed-loop control until the current error is zero.

4. The motor state estimation method according to claim 1, characterized in that, The step of inputting the back EMF deviation into the PI control structure for closed-loop control to determine the rotor speed and position angle of the motor includes: Construct an angle estimation regulator, wherein the angle estimation regulator adopts a PI control structure; The back EMF deviation is input into the angle estimation regulator for closed-loop control. When the back EMF deviation is zero, the rotor speed and the position angle are output through the angle estimation regulator.

5. The motor state estimation method according to claim 4, characterized in that, The step of inputting the back electromotive force deviation into the angle estimation regulator for closed-loop control includes: The rotor speed is determined based on the back EMF deviation. The rotor speed is integrated, and the position angle is determined based on the integration result. The back EMF deviation is re-determined based on the position angle and input into the angle estimation regulator for closed-loop control until the back EMF deviation is zero.

6. The motor state estimation method according to any one of claims 1 to 5, characterized in that, The closed-loop control of the back EMF deviation is executed in the controller interrupt procedure with priority over the closed-loop control of the rotor speed and the position angle.

7. A motor controller, characterized in that, include: The first module is used to determine the current error based on the observed current value and the current feedback value of the motor, and input the current error into the PI control structure for closed-loop control to determine the back electromotive force deviation. The second module is used to input the back EMF deviation into the PI control structure for closed-loop control to determine the rotor speed and position angle of the motor. The determination of current error based on the observed current value and current feedback value of the motor includes: The observed current value is determined based on the stator dynamic voltage and the stator static voltage. The stator dynamic voltage is the stator phase voltage under the condition that the rotor magnetic field orientation has an angular deviation, and the stator static voltage is the stator phase voltage under the steady-state condition. The current feedback value is determined based on the stator current during motor operation; The current error is determined based on the difference between the observed current value and the current feedback value.

8. An electric drive assembly, characterized in that, Includes an electric motor and the motor controller as described in claim 7.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the motor state estimation method as described in any one of claims 1 to 6.

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