Rotor zero deviation determination method, motor current loop control method and electronic equipment

Abstract

The invention relates to the technical field of electric power steering, and provides a rotor zero deviation determination method, a motor current loop control method and electronic equipment. The rotor zero deviation determination method comprises the steps of outputting d-axis current and a target positive rotation speed to a motor, tracking an actual positive rotation speed of a rotor by using a PI controller, and obtaining a first deviation angle of the rotor according to proportional term output and integral term output of the PI controller when the rotor reaches a stable positive rotation speed; d-axis current and the target negative rotating speed are output to the motor, the actual negative rotating speed of the rotor is tracked through the PI controller, and a second deviation angle of the rotor is obtained according to proportional term output and integral term output of the PI controller when the rotor reaches the stable negative rotating speed; and obtaining an actual deviation angle of the rotor according to the first deviation angle and the second deviation angle. The method does not depend on a hardware circuit, the high-precision rotor zero deviation is obtained through the efficient and low-cost software self-adaptive adjustment process, the algorithm accuracy is high, and the robustness is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of motor power steering, in particular to a rotor zero deviation determination method, a motor current loop control method and an electronic device. BACKGROUND

[0002] In an electric power steering (EPS) system, the torque of the motor is usually small. To accurately control the torque of the motor, the accurate tracking of the motor position is indispensable. In engineering, the rotor position is obtained by an encoder or resolver installed on the motor shaft. In theory, the zero position of the encoder / resolver should coincide with the rotor zero position, but due to the current installation process, the rotor zero position deviates.

[0003] At present, most schemes rely on manual calibration of the rotor zero position, and the given d-axis current is used to determine whether the motor outputs torque. This method not only needs to drag the motor to the test bench, but also the accuracy of the zero position depends largely on the experience of the engineer and the accuracy of the torque sensor of the test bench.

[0004] In addition, some schemes realize zero position self-learning through back electromotive force zero crossing or high frequency injection. However, the back electromotive force zero crossing method requires specific hardware and acquisition circuit, which increases the cost; the high frequency injection method is greatly affected by parameters, and high frequency loss is easy to occur.

[0005] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the present application, and therefore can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0006] Therefore, the present application provides a rotor zero deviation determination method, a motor current loop control method and an electronic device, which do not depend on hardware circuits, can obtain high-precision rotor zero deviation through an efficient and low-cost software adaptive adjustment process, and have high algorithm accuracy and good robustness.

[0007] According to one aspect of the present application, a rotor zero deviation determination method is provided, comprising: outputting a d-axis current and a target positive speed to a motor, tracking an actual positive speed of a rotor by using a PI controller, and obtaining a first deviation angle of the rotor according to the proportional term output and the integral term output of the PI controller when the rotor reaches a stable positive speed; outputting the d-axis current and a target negative speed to the motor, tracking an actual negative speed of the rotor by using the PI controller, and obtaining a second deviation angle of the rotor according to the proportional term output and the integral term output of the PI controller when the rotor reaches a stable negative speed; and obtaining an actual deviation angle of the rotor according to the first deviation angle and the second deviation angle.

[0008] In some embodiments, tracking the actual positive speed of the rotor using the PI controller includes: outputting a motor positive speed control signal based on the speed difference between the actual positive speed of the rotor and the target positive speed, so that the actual positive speed of the rotor tends towards the target positive speed until the rotor reaches the stable positive speed; tracking the actual negative speed of the rotor using the PI controller includes: outputting a motor negative speed control signal based on the speed difference between the actual negative speed of the rotor and the target negative speed, so that the actual negative speed of the rotor tends towards the target negative speed until the rotor reaches the stable negative speed.

[0009] In some embodiments, the PI controller is used to track the actual positive rotational speed of the rotor, which includes the following process of obtaining the proportional term output of the PI controller at the current moment: obtaining the product of the rotational speed difference of the rotor at the current moment and the proportional term parameter of the PI controller at the current moment, as the proportional term output of the PI controller at the current moment; wherein, the proportional term parameter of the PI controller at the current moment is determined based on the rotational speed difference of the rotor at the current moment.

[0010] In some embodiments, tracking the actual positive rotational speed of the rotor using the PI controller includes the following process for obtaining the integral term output of the PI controller at the current moment: obtaining the product of the rotor speed difference at the current moment, the integral term parameter of the PI controller at the current moment, and the control period, as the integral term input of the PI controller at the current moment; wherein, the integral term parameter of the PI controller at the current moment is determined based on the rotor speed difference at the current moment; obtaining the sum of the integral term output of the PI controller at the previous moment, the integral term input of the PI controller at the current moment, and the integral term deviation of the PI controller at the previous moment, as the integral value of the PI controller at the current moment; obtaining the integral value of the PI controller at the current moment and the limiting operation output of the limiter, as the integral term output of the PI controller at the current moment; wherein, the upper limit value and the lower limit value of the limiter are determined based on the proportional term output of the PI controller at the current moment; and obtaining the difference between the integral value of the PI controller at the current moment and the limiting operation output at the current moment, as the integral term deviation of the PI controller at the current moment.

[0011] In some embodiments, the PI controller is used to track the actual negative speed of the rotor, including the process of obtaining the proportional term output of the PI controller at the current moment and the process of obtaining the integral term output of the PI controller at the current moment.

[0012] In some embodiments, obtaining the first deviation angle of the rotor includes: obtaining the sum of the proportional term output and the integral term output of the PI controller when the rotor reaches a stable positive speed, as the first deviation angle; obtaining the second deviation angle of the rotor includes: obtaining the sum of the proportional term output and the integral term output of the PI controller when the rotor reaches a stable negative speed, as the second deviation angle.

[0013] In some embodiments, obtaining the actual deviation angle of the rotor includes averaging the first deviation angle and the second deviation angle as the actual deviation angle.

[0014] According to another aspect of the present invention, a motor current loop control method is provided, the motor current loop control method being implemented based on the rotor zero-position deviation determination method as described in any of the above embodiments, comprising: obtaining a rotor control angle based on a collected rotor angle and the actual deviation angle; obtaining a feedback current of the motor based on a DQ coordinate system using Clark transform and Park transform based on a collected motor current and the rotor control angle; obtaining a control voltage based on a DQ coordinate system based on a received command current based on the DQ coordinate system and the feedback current; obtaining a control voltage based on an α-β coordinate system using iPark transform based on the control voltage based on the DQ coordinate system and the rotor control angle; and modulating the control voltage based on the α-β coordinate system to generate a pulse control signal output to the motor.

[0015] In some embodiments, a control voltage based on the DQ coordinate system is obtained based on one or more control algorithms among internal model control, PI control, and feedforward compensation control; and the control voltage based on the α-β coordinate system is modulated based on the FOC modulation algorithm and the SVPWM modulation algorithm.

[0016] According to another aspect of the present invention, an electronic device is provided for implementing the method as described in any of the above embodiments.

[0017] The beneficial effects of this invention compared to the prior art include at least the following:

[0018] The rotor zero-position deviation determination method of this invention drives the rotor to rotate via d-axis current, and uses a PI controller to track the rotor speed, making the rotor speed approach the target speed. When the rotor speed stabilizes, the rotor deviation angle is obtained based on the proportional and integral terms of the PI controller. To eliminate the influence of friction and improve the learning accuracy, this invention drives the rotor to rotate in both forward and reverse directions, and uses a PI controller to track the deviation angles of the rotor in both directions to ensure high-precision rotor zero-position deviation.

[0019] Therefore, the rotor zero-position deviation determination method of the present invention does not rely on hardware circuits and can obtain high-precision rotor zero-position deviation through an efficient and low-cost software adaptive adjustment process. The algorithm has high accuracy and good robustness.

[0020] Furthermore, this invention constructs a special speed closed loop through a rotor zero-position deviation determination method, and utilizes a motor current loop control method to enable the output of the speed closed loop to directly participate in the control of the current closed loop, thereby achieving precise control of the motor.

[0021] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0022] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0023] Figure 1 This diagram illustrates the steps of the rotor zero-position deviation determination method in an embodiment of the present invention.

[0024] Figure 2 This invention illustrates an algorithm block diagram for obtaining the proportional and integral outputs of a PI controller in an embodiment of the present invention.

[0025] Figure 3 This diagram illustrates the angular relationship between the first deviation angle and the second deviation angle in an embodiment of the present invention.

[0026] Figure 4 The algorithm block diagram of the motor current loop control method in an embodiment of the present invention is shown. Detailed Implementation

[0027] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to those described herein. Rather, these embodiments are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0028] The accompanying drawings are merely illustrative of the invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0029] Furthermore, the process illustrated in the accompanying drawings is merely illustrative and does not necessarily include all steps. For example, some steps may be broken down, some steps may be combined or partially combined, and the actual order of execution may change depending on the actual situation. The use of terms such as "first," "second," and similar terms in the specific description does not indicate any order, quantity, or importance, but is merely used to distinguish different components.

[0030] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features in different embodiments can be combined with each other.

[0031] Figure 1 The main steps of the rotor zero-position deviation determination method in this embodiment of the invention are illustrated. (Refer to...) Figure 1 As shown, the rotor zero-position deviation determination method provided in this embodiment of the invention includes:

[0032] S110 outputs the d-axis current and target positive speed to the motor, uses the PI controller to track the actual positive speed of the rotor, and obtains the first deviation angle of the rotor based on the proportional and integral terms of the PI controller when the rotor reaches a stable positive speed.

[0033] The d-axis current serves as the excitation source. Since the encoder / resolver's zero position does not perfectly coincide with the rotor's zero position, a given d-axis current will produce a q-axis current component. This q-axis current component generates torque, driving the rotor to rotate. The specific value of the d-axis current can be set as needed. The target positive speed is used to drive the rotor to rotate in the forward direction. The specific value of the target positive speed can be set as needed.

[0034] Tracking the actual positive rotational speed of a rotor using a PI controller includes: outputting a motor positive rotational speed control signal based on the speed difference between the actual and target positive rotational speeds, causing the actual positive rotational speed of the rotor to approach the target positive rotational speed until the rotor reaches a stable positive rotational speed. The PI (Proportion-Integral) controller is used for precise control of the motor speed, and its output motor positive rotational speed control signal is used to regulate the actual positive rotational speed of the rotor, continuously bringing it closer to the target positive rotational speed. The technique of using a PI controller to calculate a control signal based on the rotor's speed difference to control the rotor speed to approach the target speed is existing, and this invention does not limit it. This invention mainly utilizes the proportional and integral term outputs of the PI controller during the tracking of the rotor's actual positive rotational speed, and obtains the rotor's first deviation angle based on the proportional and integral term outputs of the PI controller when the rotor reaches a stable positive rotational speed.

[0035] The stable positive speed can be equal to the target positive speed, or the difference between the stable positive speed and the target positive speed can be less than a preset threshold.

[0036] S120 outputs d-axis current and target negative speed to the motor, uses a PI controller to track the actual negative speed of the rotor, and obtains the second deviation angle of the rotor based on the proportional and integral terms of the PI controller when the rotor reaches a stable negative speed.

[0037] The target negative speed is used to drive the rotor to rotate in the opposite direction. The target negative speed is equal in value to the target positive speed but in the opposite direction.

[0038] The method of tracking the actual negative speed of the rotor using a PI controller includes: outputting a motor negative speed control signal based on the speed difference between the actual negative speed and the target negative speed, causing the actual negative speed of the rotor to tend towards the target negative speed until the rotor reaches a stable negative speed. As explained above, the PI controller is used for precise control of the motor speed, and its output motor negative speed control signal is used to regulate the actual negative speed of the rotor, causing the actual negative speed of the rotor to continuously approach the target negative speed. This invention utilizes the proportional and integral terms of the PI controller during the tracking of the actual negative speed of the rotor, and obtains the rotor's second deviation angle based on the proportional and integral terms of the PI controller when the rotor reaches a stable negative speed.

[0039] The stable negative speed can be equal to the target negative speed, or the difference between the stable negative speed and the target negative speed can be less than a preset threshold.

[0040] S130, based on the first deviation angle and the second deviation angle, obtain the actual deviation angle of the rotor.

[0041] The rotor zero-position deviation determination method of this invention drives the rotor to rotate via d-axis current, and uses a PI controller to track the rotor speed, making the rotor speed approach the target speed. When the rotor speed stabilizes, the rotor deviation angle is obtained based on the proportional and integral terms of the PI controller. To eliminate the influence of friction and improve the learning accuracy, this invention drives the rotor to rotate in both forward and reverse directions, and uses a PI controller to track the deviation angles of the rotor in both directions to ensure high-precision rotor zero-position deviation.

[0042] Therefore, the rotor zero-position deviation determination method of the present invention does not rely on hardware circuits and can obtain high-precision rotor zero-position deviation through an efficient and low-cost software adaptive adjustment process. The algorithm has high accuracy and good robustness.

[0043] Figure 2 This diagram illustrates the algorithm block diagram for obtaining the proportional and integral outputs of the PI controller, combined with... Figure 1 and Figure 2 As shown, in some embodiments, the PI controller is used to track the actual positive rotational speed of the rotor, including the following process for obtaining the proportional term output of the PI controller at the current moment:

[0044] The product of the rotor speed difference at the current moment and the proportional term parameter of the PI controller at the current moment is obtained and used as the proportional term output of the PI controller at the current moment.

[0045] The proportional term parameter (Kp) of the PI controller at the current moment is determined based on the rotor speed difference at the current moment. For example, a mapping table between any rotor parameter such as speed difference and speed change rate and the proportional term parameter can be pre-stored. When determining the proportional term parameter of the PI controller at the current moment based on the rotor speed difference, the corresponding proportional term parameter of the PI controller at the current moment can be obtained by looking up the table. Alternatively, the proportional term parameter of the PI controller can be adjusted according to other feasible methods to make the actual positive speed of the rotor follow and approach the target positive speed.

[0046] Continue to combine Figure 1 and Figure 2 As shown, in some embodiments, the PI controller is used to track the actual positive rotational speed of the rotor, including the following process for obtaining the integral term output of the PI controller at the current moment:

[0047] The product of the rotor speed difference at the current moment, the integral term parameter of the PI controller at the current moment, and the control period is obtained and used as the integral term input of the PI controller at the current moment.

[0048] The integral term parameter (Ki) of the PI controller at the current moment is determined based on the rotor speed difference at the current moment. For example, a mapping table between any rotor parameter such as speed difference and speed change rate and the integral term parameter can be pre-stored. When determining the integral term parameter of the PI controller at the current moment based on the rotor speed difference, the corresponding integral term parameter of the PI controller at the current moment can be obtained by looking up the table. Alternatively, the integral term parameter of the PI controller can be adjusted according to other feasible methods to make the actual positive speed of the rotor follow and approach the target positive speed.

[0049] The control cycle depends on the configuration of the PI controller. The current time differs from the previous time by one control cycle.

[0050] The integral term output of the PI controller at the previous moment, the integral term input of the PI controller at the current moment, and the integral term deviation of the PI controller at the previous moment are obtained as the integral value of the PI controller at the current moment.

[0051] Among them, the integral term deviation of the PI controller is the integral anti-saturation value of the PI controller.

[0052] Obtain the integral value of the PI controller at the current moment and the amplitude limiting operation output of the limiter, and use them as the integral term output of the PI controller at the current moment.

[0053] The inputs to the limiter include the integral value, upper limit, and lower limit of the PI controller at the current moment. The upper and lower limits are determined based on the proportional term output of the PI controller at the current moment. Specifically, the upper limit is obtained by subtracting the absolute value of the proportional term output of the PI controller at the current moment from the calibrated value (theoretical maximum value); the lower limit is obtained by inverting the upper limit. The limiting operation of the limiter is, for example, to subtract instantaneous values ​​of the PI controller's integral value at the current moment that exceed the upper and lower limits, while retaining other instantaneous values ​​of the PI controller's integral value at the current moment. Alternatively, other existing limiting operation methods can be used to obtain the limiting operation output based on the integral value of the PI controller at the current moment.

[0054] The difference between the integral value of the PI controller at the current moment and the output of the current limiting operation is obtained as the integral term deviation of the PI controller at the current moment.

[0055] Specifically, the current limiting operation output can be subtracted from the current integral value of the PI controller to obtain the current integral term deviation of the PI controller.

[0056] In summary, by using the above method to track the actual positive speed of the rotor using a PI controller, the proportional and integral terms of the PI controller at the current moment are obtained. By repeating this process, the proportional and integral terms of the PI controller at the moment when the rotor reaches a stable positive speed can be obtained.

[0057] Similarly, in the process of using a PI controller to track the actual negative speed of the rotor, the proportional and integral outputs of the PI controller at the current moment can be obtained by following the above method; furthermore, the proportional and integral outputs of the PI controller at the moment when the rotor reaches a stable negative speed can be obtained.

[0058] Furthermore, in some embodiments, obtaining the first deviation angle of the rotor includes: obtaining the sum of the proportional term output and the integral term output of the PI controller when the rotor reaches a stable positive speed, as the first deviation angle; obtaining the second deviation angle of the rotor includes: obtaining the sum of the proportional term output and the integral term output of the PI controller when the rotor reaches a stable negative speed, as the second deviation angle.

[0059] In calculating the first deviation angle, after obtaining the sum of the proportional and integral outputs of the PI controller when the rotor reaches a stable positive speed, the maximum and minimum angle values ​​(which can be set as needed) can be used to limit the sum of the proportional and integral outputs of the PI controller when the rotor reaches a stable positive speed. The angle value after limiting is used as the first deviation angle. Similarly, in calculating the second deviation angle, after obtaining the sum of the proportional and integral outputs of the PI controller when the rotor reaches a stable negative speed, the maximum and minimum angle values ​​can be used to limit the sum of the proportional and integral outputs of the PI controller when the rotor reaches a stable negative speed. The angle value after limiting is used as the second deviation angle.

[0060] Finally, the actual deviation angle of the rotor is obtained by averaging the first deviation angle and the second deviation angle as the actual deviation angle.

[0061] For example, Figure 3 The angular relationship between the first deviation angle and the second deviation angle is illustrated; combined with Figures 1 to 3 As shown, the ABC coordinate system is the three-phase coordinate system of the motor, and the DQ coordinate system is related to the direction of the motor's magnetic field. By controlling the motor to rotate forward and using a PI controller to track the rotor, the first deviation angle θ of the rotor is obtained. P By controlling the motor to reverse and using a PI controller to track the rotor, the second deviation angle θ of the rotor was obtained. N Furthermore, based on the first deviation angle θ P With the second deviation angle θ N The average value can be used to obtain the actual deviation angle θ of the rotor. off =(θP +θ N ) / 2.

[0062] This invention also provides a motor current loop control method based on the rotor zero-position deviation determination method described in any of the above embodiments. Figure 4 The algorithm block diagram of the motor current loop control method is shown, combined with... Figures 1 to 4 As shown, the motor current loop control method provided in this embodiment of the invention includes:

[0063] The rotor control angle is obtained based on the acquired rotor angle and the actual deviation angle. The rotor position is acquired via an encoder / resolver mounted on the motor shaft, and the rotor angle θ is calculated from this position using a rotary transformer. Furthermore, the actual deviation angle θ is calculated using a rotor zero-position deviation determination module (used to implement the aforementioned rotor zero-position deviation determination method). off To obtain the rotor control angle θ1 = θ + θ off .

[0064] Based on the acquired motor current and rotor control angle, the feedback current of the motor in the DQ coordinate system is obtained using Clark and Park transformations. The acquired motor currents (Ia, Ib, Ic) are the phase currents of the motor. The Clark transformation is used to transform the acquired motor currents (Ia, Ib, Ic) to the α-β coordinate system, and the Park transformation is used to realize the conversion from the α-β coordinate system to the DQ coordinate system. The rotor control angle θ1 is used to ensure the accuracy of the feedback currents (Idfdb, Iqfdb) obtained by the conversion.

[0065] The control voltage based on the received command current and feedback current in the DQ coordinate system is obtained. Specifically, the control voltage (Ud, Uq) can be calculated based on the command current (Idref, Iqref) and feedback current (Idfdb, Iqfdb) using one or more control algorithms, including internal model control, PI control, and feedforward compensation control. Internal model control, PI control, and feedforward compensation control are all common current loop control algorithms in the field of motor control, and this invention does not limit the application of these algorithms.

[0066] Based on the control voltage and rotor control angle in the DQ coordinate system, the control voltage in the α-β coordinate system is obtained using the iPark transformation. The iPark transformation is the inverse of the Park transformation, and it can be used to obtain the control voltage (Uα, Uβ) based on the control voltage (Ud, Uq) and rotor control angle θ1.

[0067] The control voltage based on the α-β coordinate system is modulated to generate a pulse control signal output to the motor. Specifically, based on the FOC (Field Oriented Control) modulation algorithm and the SVPWM (Space Vector Pulse Width Modulation) modulation algorithm, a pulse control signal (Duty) is generated from the control voltage (Uα, Uβ) based on the α-β coordinate system and output to the motor to control the motor rotation.

[0068] This invention constructs a special speed closed loop through a rotor zero-position deviation determination method, and utilizes a motor current loop control method to enable the output of the speed closed loop to directly participate in the control of the current closed loop, thereby achieving precise control of the motor.

[0069] This invention also provides an electronic device that can be used to implement the rotor zero-position deviation determination method and / or motor current loop control method described in any of the above embodiments. The electronic device can be independently configured in a vehicle, integrated into the vehicle's controller (e.g., motor controller, inverter), or remotely deployed and communicatively connected to the vehicle's controller. The electronic device can take the following forms:

[0070] Presented in the form of a functional (program) module architecture, it may include modules that respectively implement each step of the rotor zero position deviation determination method / motor current loop control method described above, such as a first deviation angle acquisition module for implementing step S110, a second deviation angle acquisition module for implementing step S120, and an actual deviation angle acquisition module for implementing step S130.

[0071] In the form of a general-purpose computing device, it may include a processing unit and a storage unit. The storage unit stores executable instructions. When the executable instructions are executed by the processing unit, they implement the rotor zero-position deviation determination method / motor current loop control method described in any of the above embodiments.

[0072] The storage unit may include programs / utilities with one or more program modules, including but not limited to: an operating system, one or more application programs, other program modules, and program data. The general-purpose computing device also includes a bus connecting the processing unit and the storage unit, as well as other platform components. This bus may include a storage unit bus, a peripheral bus, a graphics acceleration port, a processing unit bus, and other local area buses. The general-purpose computing device can also communicate with one or more external devices, other computing devices in the vehicle, networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks such as the Internet).

[0073] It is represented in the form of a storage medium, which stores a program that, when executed, implements the rotor zero-position deviation determination method / motor current loop control method described in any of the above embodiments.

[0074] The storage medium can be any tangible medium that contains or stores a program, specifically any combination of one or more readable media, which can be a readable signal medium or a readable storage medium. The program can be used by or in conjunction with an instruction execution system, apparatus, or device. The program can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device, for example, via the Internet using an Internet service provider.

[0075] It is manifested in the form of a computer program product, which includes a computer program that, when executed by the vehicle's controller, implements the rotor zero-position deviation determination method / motor current loop control method described in any of the above embodiments.

[0076] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for determining rotor zero-position deviation, characterized in that, include: The motor outputs d-axis current and target positive speed, uses a PI controller to track the actual positive speed of the rotor, and obtains the first deviation angle of the rotor based on the proportional and integral terms of the PI controller when the rotor reaches a stable positive speed. The d-axis current and target negative speed are output to the motor. The actual negative speed of the rotor is tracked by the PI controller. The second deviation angle of the rotor is obtained based on the proportional and integral terms of the PI controller when the rotor reaches a stable negative speed. The actual deviation angle of the rotor is obtained based on the first deviation angle and the second deviation angle.

2. The rotor zero-position deviation determination method as described in claim 1, characterized in that: Tracking the actual positive speed of the rotor using the PI controller includes: outputting a motor positive speed control signal based on the speed difference between the actual positive speed of the rotor and the target positive speed, so that the actual positive speed of the rotor tends to the target positive speed until the rotor reaches the stable positive speed; Tracking the actual negative speed of the rotor using the PI controller includes: outputting a motor negative speed control signal based on the speed difference between the actual negative speed of the rotor and the target negative speed, so that the actual negative speed of the rotor tends to the target negative speed until the rotor reaches the stable negative speed.

3. The rotor zero-position deviation determination method as described in claim 1, characterized in that, Tracking the actual positive rotational speed of the rotor using the PI controller includes the following process for obtaining the proportional term output of the PI controller at the current moment: The product of the rotor speed difference at the current moment and the proportional term parameter of the PI controller at the current moment is obtained and used as the proportional term output of the PI controller at the current moment; The proportional term parameter of the PI controller at the current moment is determined based on the rotor speed difference at the current moment.

4. The rotor zero-position deviation determination method as described in claim 3, characterized in that, Tracking the actual positive rotational speed of the rotor using the PI controller includes the following process for obtaining the integral term output of the PI controller at the current moment: The product of the rotor speed difference at the current moment, the integral term parameter of the PI controller at the current moment, and the control period is obtained and used as the integral term input of the PI controller at the current moment. Wherein, the integral term parameter of the PI controller at the current moment is determined based on the rotor speed difference at the current moment; The integral term output of the PI controller at the previous moment, the integral term input of the PI controller at the current moment, and the integral term deviation of the PI controller at the previous moment are obtained as the integral value of the PI controller at the current moment. Obtain the integral value of the PI controller and the limiting operation output of the limiter at the current moment, and use them as the integral term output of the PI controller at the current moment; The upper and lower limits of the limiter are determined based on the proportional term output of the PI controller at the current moment; and The difference between the integral value of the PI controller at the current moment and the amplitude limiting operation output at the current moment is obtained as the integral term deviation of the PI controller at the current moment.

5. The rotor zero-position deviation determination method as described in claim 3 or 4, characterized in that, Tracking the actual negative speed of the rotor using the PI controller includes the process of obtaining the proportional term output of the PI controller at the current moment and the process of obtaining the integral term output of the PI controller at the current moment.

6. The rotor zero-position deviation determination method as described in claim 1, characterized in that: Obtaining the first deviation angle of the rotor includes: obtaining the sum of the proportional term output and the integral term output of the PI controller when the rotor reaches a stable positive speed, as the first deviation angle; Obtaining the second deviation angle of the rotor includes: obtaining the sum of the proportional and integral outputs of the PI controller when the rotor reaches a stable negative speed, as the second deviation angle.

7. The rotor zero-position deviation determination method as described in claim 1, characterized in that, Obtaining the actual deviation angle of the rotor includes: The average of the first deviation angle and the second deviation angle is taken as the actual deviation angle.

8. A motor current loop control method, characterized in that, Based on the rotor zero-position deviation determination method as described in any one of claims 1-7, including: The rotor control angle is obtained based on the collected rotor angle and the actual deviation angle; Based on the collected motor current and the rotor control angle, the feedback current of the motor based on the DQ coordinate system is obtained using Clark transformation and Park transformation. Based on the received command current and feedback current based on the DQ coordinate system, a control voltage based on the DQ coordinate system is obtained; Based on the control voltage in the DQ coordinate system and the rotor control angle, the control voltage in the α-β coordinate system is obtained using the iPark transformation; The control voltage based on the α-β coordinate system is modulated to generate a pulse control signal, which is then output to the motor.

9. The current loop control method as described in claim 8, characterized in that, Based on one or more control algorithms such as internal model control, PI control, and feedforward compensation control, the control voltage based on the DQ coordinate system is obtained. The control voltage based on the α-β coordinate system is modulated using the FOC modulation algorithm and the SVPWM modulation algorithm.

10. An electronic device, characterized in that, Used to implement the method as described in any one of claims 1-9.

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