A motor control method, system and electric power assisted vehicle

Abstract

The present application relates to the field of motor control technology, and discloses a motor control method, a system and an electric power-assisted vehicle. The motor control method includes: obtaining sensor signals and three-phase currents; obtaining an initial assistance torque based on the input voltage of an in-motor torque sensor, and performing active damping on the initial assistance torque to obtain an adjusted assistance torque; inputting the error between the adjusted current and the feedback current into a current loop to output an initial direct and quadrature axis control voltage; calculating the electrical angular velocity, and determining a voltage coupling term based on the feedback current and the electrical angular velocity; using the voltage coupling term to perform feedback compensation on the initial direct and quadrature axis control voltage to obtain a target direct and quadrature axis control voltage; obtaining three-phase voltage control signals according to the target direct and quadrature axis control voltage to drive the motor to rotate. This motor control method can solve the resonance problem that occurs during the acceleration and deceleration of the vehicle, eliminate the influence of the slow convergence of the current loop on the voltage term, and ensure that the assistance response speed is not affected by various operating conditions.

Description

Technical Field

[0001] This application relates to the technical field of motor control, and particularly to a motor control method, system, and electric assist vehicle. Background Art

[0002] With the popularity of electric assist vehicles globally, people's expectations for their performance and riding experience are constantly increasing. A mid-mounted motor is an electric motor installed in the middle of the vehicle body. Due to its excellent controllability and power performance, the mid-mounted motor has become an ideal choice for many high-performance electric assist vehicles. However, in actual use, the mid-mounted motor also faces some technical challenges, which affect its performance under different riding conditions. The mid-mounted motor is a permanent magnet synchronous motor. When performing vector control (field-oriented control, FOC) on the motor and the operating conditions of the motor change, the bandwidth of the current loop will decay, and the motor assist response speed is greatly affected by the rotational speed, which affects the dynamic performance of the motor. Summary of the Invention

[0003] In view of this, embodiments of this application provide a motor control method, system, and electric assist vehicle, aiming to solve the problem that the motor assist response speed is greatly affected by the rotational speed.

[0004] In a first aspect, embodiments of this application provide a motor control method, including:

[0005] Obtain sensor signals in the vehicle and three-phase currents of the motor, where the sensor signals include the input voltage of the motor built-in torque sensor when the user acts on the vehicle and the motor electrical angle sampled in real time;

[0006] Obtain the initial assist torque acting on the motor based on the input voltage of the motor built-in torque sensor, and perform active damping on the initial assist torque to obtain an adjusted assist torque;

[0007] Determine the adjusted current of the motor according to the adjusted assist torque, and calculate the feedback current of the motor according to the three-phase currents;

[0008] Input the error between the adjusted current and the feedback current into the current loop, and output the initial direct and quadrature axis control voltages of the motor;

[0009] Calculate the corresponding electrical angular velocity according to the electrical angle, and determine the voltage coupling term based on the feedback current and the electrical angular velocity;

[0010] Use the voltage coupling term to perform feedback compensation on the initial direct and quadrature axis control voltages to obtain the target direct and quadrature axis control voltages;

[0011] Based on the target direct-axis and quadrature-axis control voltages, three-phase voltage control signals for input to the motor are obtained to drive the motor to rotate.

[0012] In the first possible embodiment of the first aspect, the regulating current includes a direct-axis regulating current and a quadrature-axis regulating current, the feedback current includes a direct-axis feedback current and a quadrature-axis feedback current, and inputting the error between the regulating current and the feedback current into a current loop to output the initial direct-axis and quadrature-axis control voltages of the motor includes:

[0013] Taking the error between the direct-axis regulating current and the direct-axis feedback current as the first input quantity of the current loop;

[0014] Taking the error between the quadrature-axis regulating current and the quadrature-axis feedback current as the second input quantity of the current loop.

[0015] In the second possible embodiment of the first aspect, inputting the error between the regulating current and the feedback current into a current loop to output the initial direct-axis and quadrature-axis control voltages of the motor further includes:

[0016] Converging the first input quantity through a direct-axis current loop to obtain an initial direct-axis control voltage;

[0017] Converging the second input quantity through a quadrature-axis current loop to obtain an initial quadrature-axis control voltage.

[0018] In the third possible embodiment of the first aspect, determining the voltage coupling term based on the feedback current and the electrical angular velocity includes:

[0019] Calculating a direct-axis voltage coupling term according to the electrical angular velocity, quadrature-axis inductance, and quadrature-axis feedback current;

[0020] Calculating a quadrature-axis voltage coupling term according to the electrical angular velocity, direct-axis inductance, magnetic flux, and direct-axis feedback current.

[0021] In the fourth possible embodiment of the first aspect, the calculation formula for the direct-axis voltage coupling term is:

[0022] (1)

[0023] In formula (1), represents the direct-axis voltage coupling term, represents the electrical angular velocity, represents the quadrature-axis inductance, represents the quadrature-axis feedback current;

[0024] The calculation formula for the quadrature-axis voltage coupling term is:

[0025] (2)

[0026] In Equation (2), represents the quadrature-axis voltage coupling term, represents the direct-axis inductance, represents the magnetic flux linkage, represents the direct-axis feedback current.

[0027] In a fifth possible embodiment of the first aspect, before obtaining the adjusted assist torque by actively damping the initial assist torque, the method further includes:

[0028] Filtering the initial assist torque through a first filter to obtain an optimized assist torque.

[0029] In a sixth possible embodiment of the first aspect, obtaining the adjusted assist torque by actively damping the initial assist torque includes:

[0030] Inputting the electrical angular velocity into an active damper for processing and outputting a corresponding damping torque, and using the damping torque to adjust the optimized assist torque to obtain the adjusted assist torque.

[0031] In a seventh possible embodiment of the first aspect, inputting the electrical angular velocity into an active damper for processing and outputting a corresponding damping torque includes:

[0032] Filtering the electrical angular velocity through a second filter to obtain electrical angular velocity fluctuations;

[0033] Calculating the damping torque according to the electrical angular velocity fluctuations and a preset damping coefficient.

[0034] In a second aspect, an embodiment of the present application provides a motor control system, including:

[0035] A vehicle main control module for obtaining sensor signals in the vehicle and three-phase currents of the motor, wherein the sensor signals include the input voltage of the motor built-in torque sensor when the user acts on the vehicle and the motor electrical angle sampled in real time, and the initial assist torque acting on the motor obtained based on the input voltage of the motor built-in torque sensor;

[0036] An active damping module for actively damping the initial assist torque to obtain an adjusted assist torque;

[0037] A current distribution module for determining the adjusted current of the motor according to the adjusted assist torque;

[0038] A calculation module for calculating the feedback current of the motor according to the three-phase currents, and calculating the corresponding electrical angular velocity according to the electrical angle;

[0039] A current loop module, configured to input the error between the regulated current and the feedback current into the current loop and output the initial direct and quadrature axis control voltages of the motor;

[0040] A decoupling module, configured to determine a voltage coupling term based on the feedback current and the electrical angular velocity, and perform feedback compensation on the initial direct and quadrature axis control voltages by using the voltage coupling term to obtain target direct and quadrature axis control voltages;

[0041] A motor drive module, configured to obtain three-phase voltage control signals for input to the motor according to the target direct and quadrature axis control voltages to drive the motor to rotate.

[0042] In a third aspect, an embodiment of the present application provides an electric power-assisted vehicle, including a motor control system, and the motor control system is configured to execute the above-mentioned motor control method.

[0043] The embodiments of the present application have the following beneficial effects:

[0044] A motor control method according to this embodiment includes: acquiring sensor signals in the vehicle and three-phase currents of the motor; obtaining an initial assist torque based on the input voltage of an in-motor torque sensor, and performing active damping on the initial assist torque to obtain a regulated assist torque; inputting the error between the regulated current and the feedback current into the current loop and outputting initial direct and quadrature axis control voltages; calculating the electrical angular velocity, and determining a voltage coupling term based on the feedback current and the electrical angular velocity; performing feedback compensation on the initial direct and quadrature axis control voltages by using the voltage coupling term to obtain target direct and quadrature axis control voltages; obtaining three-phase voltage control signals according to the target direct and quadrature axis control voltages to drive the motor to rotate. This motor control method reduces the speed fluctuation through active damping, solves the resonance problem that occurs during the acceleration and deceleration of the vehicle, and then performs feedback compensation on the direct and quadrature axis control voltages according to the voltage coupling term, eliminating the influence of the slow convergence of the voltage coupling term when the current loop calculates the direct and quadrature axis control voltages, ensuring that the bandwidth of the current loop does not decay during the acceleration, deceleration, and high-speed operation processes, that is, the assist response speed is not affected by various operating conditions. Description of the Drawings

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0046] Figure 1 Shows a schematic structural diagram of an electric power-assisted vehicle according to an embodiment of the present application;

[0047] Figure 2Shows a first flow schematic diagram of the motor control method according to an embodiment of the present application;

[0048] Figure 3 Shows a schematic diagram of the motor speed during the vehicle acceleration process according to an embodiment of the present application;

[0049] Figure 4 Shows a spectral schematic diagram of the motor speed during the vehicle acceleration process according to an embodiment of the present application;

[0050] Figure 5 Shows a schematic diagram of the motor speed and motor speed fluctuation after being filtered by a second filter according to an embodiment of the present application;

[0051] Figure 6 Shows a second flow schematic diagram of the motor control method according to an embodiment of the present application;

[0052] Figure 7 Shows a schematic structural diagram of a motor control system according to an embodiment of the present application.

[0053] Main element symbol description:

[0054] 200 - Motor control system; 210 - Vehicle main control module; 220 - Active damping module; 230 - Current distribution module; 240 - Calculation module; 250 - Current loop module; 260 - Decoupling module; 270 - Motor drive module. Detailed implementation manners

[0055] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments.

[0056] Generally, the components of the embodiments of the present application described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application to be protected, but only represents the selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.

[0057] As used hereinafter, the terms "comprising", "having" and their cognates that may be used in various embodiments of the present application are only intended to indicate specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be construed as precluding the existence or adding the possibility of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance.

[0058] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the various embodiments of the present application belong. The terms (such as those defined in a commonly used dictionary) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and will not be interpreted as having an idealized meaning or an overly formal meaning unless clearly defined in the various embodiments of the present application.

[0059] The following will describe in detail some embodiments of the present application with reference to the accompanying drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0060] In view of the problems of large speed fluctuations and low motor boost response speed in the current motor control system, the present application provides a motor control method. By actively damping the boost torque of the motor, the problem of acceleration and deceleration resonance is effectively solved. On the basis of solving the acceleration and deceleration resonance problem, the voltage coupling term is compensated to the output end of the current loop to eliminate the problem that the current loop fails to converge the voltage coupling term in time, resulting in a slow boost response speed.

[0061] Before describing the motor control method of the present application, the structure of the electric assist vehicle will be introduced accordingly.

[0062] Figure 1 FIG. shows a schematic structural diagram of an electric assist vehicle proposed in an embodiment of the present application. The electric assist vehicle can be an electric bicycle, an electric motorcycle, an electric tricycle, etc. Exemplarily, the main structure of the electric assist vehicle includes a frame, a motor, a battery, a controller, a charger, a dashboard, a braking system, a shock absorption system, wheels and tires, etc. The electric assist vehicle also includes a motor control system. Among them, the voltage control system is used to execute the motor control method, drive the motor to rotate, provide auxiliary power, reduce the physical consumption of the driver, improve the controllability and driving comfort, and enhance the overall driving experience. The motor control system includes a processor and a memory. The memory stores a computer program, and the processor runs the computer program to enable the motor control system to execute the motor control method.

[0063] Among them, the processor can be an integrated circuit chip with signal processing capabilities. The processor can be a general-purpose processor, including at least one of a central processing unit (CPU), a graphics processing unit (GPU), a network processor (NP), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc., and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application.

[0064] The memory can be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc. Among them, the memory is used to store a computer program, and after receiving an execution instruction, the processor can execute the computer program accordingly.

[0065] The following will illustrate the motor control method in conjunction with some specific embodiments.

[0066] Figure 2 A flowchart of the motor control method according to an embodiment of the present application is shown. Exemplarily, the motor control method includes the following steps:

[0067] S110, obtain the sensor signals in the vehicle and the three-phase current of the motor. Among them, the sensor signals include the input voltage of the motor built-in torque sensor when the user acts on the vehicle and the motor electrical angle sampled in real time.

[0068] In the embodiments of the present application, corresponding sensor signals can be obtained through multiple sensors provided on an electric assist vehicle. For example, the sensors can include, but are not limited to, a cadence sensor, a wheel speed sensor, a temperature sensor, an electronic brake lever, an inertial sensor, a pedal torque sensor, a magnetic encoder, an electronic throttle sensor, etc. Among them, the cadence sensor usually collects cadence pulse signals, and measures the cadence of the vehicle according to the number of cadence pulse signals. The magnetic encoder is used to measure the electrical angle of the motor. The pedal torque sensor is used to measure the force and position applied by the rider when stepping on the pedal, and converts it into the input voltage (V_sensor) of the built-in torque sensor of the motor. Alternatively, the position or angle change of the throttle can also be detected through the electronic throttle sensor, and converted into the input voltage (V_sensor) of the built-in torque sensor of the motor. In the present application, the three-phase current (Ia_fdk / Ib_fdk / Ic_fdk) of the motor can be obtained by setting a sampling resistor at the low end of each lower bridge arm.

[0069] S120. Obtain an initial assist torque acting on the motor based on the input voltage of the built-in torque sensor of the motor, and perform active damping on the initial assist torque to obtain an adjusted assist torque.

[0070] In one embodiment, the present application analyzes and processes all the received information, including the electronic gear and other sensor signals, through a vehicle control strategy, and converts it into the input voltage of the built-in torque sensor of the motor, and outputs a corresponding initial assist torque (Te). The initial assist torque provides appropriate assistance through the motor on the basis of the rider's human power. Among them, different input voltages represent different electronic gears, and different electronic gears correspond to different transmission ratios or preset motor output characteristics. For example, in a high gear, the motor may output at a higher speed and a larger torque to meet the needs of high-speed riding; while in a low gear, the motor may provide a larger starting torque, which is suitable for climbing or low-speed high-torque requirements.

[0071] In one embodiment, in view of the impact problem existing in acceleration and deceleration caused by the gear clearance of the electric assist vehicle, the present application filters the initial assist torque through a first filter to obtain an optimized assist torque (Te_flt). Among them, the first filter can be a first-order low-pass filter, which can smooth the signal, remove high-frequency noise and improve the control accuracy.

[0072] In the embodiments of the present application, the motor speed during the vehicle acceleration process is captured, such as Figure 3 As shown, there are violent fluctuations in the motor speed during the acceleration process, resulting in uneven assistance perceived by the rider during the riding process. The motor speed is analyzed through fast Fourier transform (FFT), and by Figure 4It can be seen that the amplitude of the harmonic components within 13~20 Hz is significantly greater than that of other nearby frequency components, indicating that there is a resonance problem in the vehicle system.

[0073] In one embodiment, to address the resonance problem that occurs during the acceleration and deceleration of the vehicle system, the present application samples the electrical angle of the motor (e_angle) through a magnetic encoder. After the magnetic encoder samples the electrical angle, the frequency measurement method (M method) is used to count the number of pulses of the magnetic encoder within a unit time, thereby calculating the electrical angular velocity value (e_omega). The present application removes the low-frequency components and DC components through a second filter to extract the effective electrical angular velocity fluctuation (e_omega_ac). Among them, the second filter is a first-order high-pass filter, which can remove low-frequency interference and DC offset caused by mechanical structure, sensor deviation, or other environmental factors, thereby obtaining a more accurate electrical angular velocity fluctuation signal. According to the conversion formula between the electrical angular velocity of the motor and the motor speed, the motor speed and the motor speed fluctuation can be obtained. The motor speed after being filtered by the first filter is as Figure 5 shown, and it can be seen that the motor speed fluctuation is completely filtered out, while the original normal acceleration signal remains unaffected.

[0074] In one embodiment, the motor control method determines the damping torque based on the product of the speed fluctuation filtered by the second filter and a preset damping coefficient. Among them, the damping torque Te_resist (N*m) = damping coefficient c (N*m*min / r) * motor speed fluctuation (r / min, revolutions per minute). The filtered assist torque is adjusted through negative feedback based on the damping torque to obtain the adjusted assist torque. When the vehicle accelerates, the optimized assist torque is appropriately reduced based on the damping torque. When the vehicle decelerates, the optimized assist torque is appropriately increased based on the damping torque, thereby avoiding large fluctuations in speed during the acceleration and deceleration processes, which may cause an uneven perception of assistance during the rider's journey.

[0075] In an alternative embodiment, the optimal value range of the preset damping coefficient can be set to [-130, -100], that is, when the vehicle speed increases, the assist torque of the motor is reduced, and when the vehicle speed decreases, the input torque of the motor is increased to stabilize the motor speed.

[0076] S130, determine the adjustment current of the motor based on the adjusted assist torque, and calculate the feedback current of the motor according to the three-phase current;

[0077] In one embodiment, the regulated current of the motor includes a direct-axis regulated current and a quadrature-axis regulated current. The direct-axis current control strategy (Id = 0) or the MTPA control strategy can be used to determine the direct-axis regulated current (Id_ref) and the quadrature-axis regulated current (Iq_ref). The direct-axis current control strategy is as follows: according to the regulated assist torque, the direct-axis regulated current is set to zero, and the torque of the motor is completely generated by the quadrature-axis current (Iq). Therefore, the quadrature-axis regulated current will be set according to the required regulated assist torque. The MTPA control strategy is as follows: at a given current amplitude, by optimizing the distribution of the direct-axis regulated current and the quadrature-axis regulated current, the output of the regulated assist torque is achieved.

[0078] In another embodiment, the feedback current of the motor includes a direct-axis feedback current (Id_fdk) and a quadrature-axis feedback current (Iq_fdk). The three-phase current is transformed into the direct-axis feedback current and the quadrature-axis feedback current through Clark transformation and Park transformation. Among them, the Clark transformation is to transform the three-phase current in the three-phase coordinate system into the current in the two-phase stationary coordinate system; the Park transformation is to transform the current in the two-phase stationary coordinate system into the current in the two-phase rotating coordinate system, that is, the direct-axis feedback current and the quadrature-axis feedback current.

[0079] S140, input the error between the regulated current and the feedback current into the current loop, and output the initial direct and quadrature-axis control voltages.

[0080] In one embodiment, the present application converts the control of the direct and quadrature-axis control voltages through the current loop into a single-loop control system with two independent control channels, including a direct-axis current loop and a quadrature-axis current loop, which can accurately process the independent control of the two-axis current to achieve accurate torque control. The current loop realizes the accurate control of the output of the motor system through the adjustment of two parameters, proportional and integral. The proportional control function is to adjust the direct and quadrature-axis control voltages according to the difference between the direct-axis regulated current and the direct-axis feedback current, and the integral control function adjusts the direct and quadrature-axis control voltages through the integral deviation, which can eliminate the steady-state error.

[0081] In one embodiment, the error between the direct-axis regulated current and the direct-axis feedback current is used as the first input quantity of the current loop, and the first input quantity is converged through the direct-axis current loop to obtain the initial direct-axis control voltage. The direct-axis current loop forms a control deviation according to the direct-axis regulated current and the direct-axis feedback current, and linearly combines the proportional and integral of the deviation to form the initial direct-axis control voltage to control the motor speed. The transfer function of the direct-axis current loop is: , where is the proportional gain of the direct-axis current loop, is the integral gain of the direct-axis current loop, is the complex variable.

[0082] In another embodiment, the error between the quadrature-axis regulating current and the quadrature-axis feedback current is used as the second input of the current loop, and the second input is converged through the quadrature-axis current loop to obtain the initial quadrature-axis control voltage. The quadrature-axis current loop forms a control deviation based on the quadrature-axis regulating current and the quadrature-axis feedback current, and forms the initial direct-axis control voltage through a linear combination of the proportional and integral parts of the deviation to control the motor speed. The transfer function of the quadrature-axis current loop is: , where is the proportional gain of the quadrature-axis current loop, is the integral gain of the quadrature-axis current loop.

[0083] S150. Calculate the corresponding electrical angular velocity according to the electrical angle, and determine the voltage coupling term based on the feedback current and the electrical angular velocity.

[0084] In the embodiment of the present application, a decoupling module is added after the active damping of the assist torque. This is because if the decoupling module is added before the resonance problem is solved, the speed fluctuation will cause the compensated voltage fluctuation, and the speed fluctuation will be further amplified. Therefore, the decoupling function can only be enabled when the speed fluctuation is small. The motor voltage equation is:

[0085] (1)

[0086] In formula (1), represents the direct-axis (d-axis) voltage of the motor, represents the quadrature-axis (q-axis) voltage of the motor, represents the d-axis current value, is the q-axis current value, is the electrical angular velocity of the motor, is the d-axis inductance, is the q-axis inductance, is the phase resistance, is the permanent magnet flux linkage. It can be seen from the motor voltage equation that there is a voltage coupling term between the d / q-axis voltages. The d-axis voltage equation couples the q-axis parameters ( ), and the q-axis voltage equation couples the d-axis parameters . And when the electrical angular velocity increases, the voltage ratio of the coupling term will become larger, and it is difficult for the current loop to converge quickly at this time. Therefore, the current loop bandwidth will be affected. To solve the problem of slow response speed of the motor system during acceleration, deceleration and high-speed operation, the present application adds a decoupling module to the current loop.

[0087] In one embodiment, the present application calculates the direct-axis voltage coupling term according to the electrical angular velocity, the quadrature-axis inductance and the quadrature-axis feedback current. The calculation formula of the direct-axis voltage coupling term is: . Calculate the quadrature-axis voltage coupling term according to the electrical angular velocity, the direct-axis inductance, the flux linkage and the direct-axis feedback current. The calculation formula of the quadrature-axis voltage coupling term is: 。

[0088] S160. Use the voltage coupling term to perform feedback compensation on the initial direct and quadrature axis control voltages to obtain the target direct and quadrature axis control voltages.

[0089] In one embodiment, the present application performs feedback compensation on the initial direct axis control voltage with the direct axis voltage coupling term to obtain the target direct axis control voltage; and performs feedback compensation on the initial quadrature axis control voltage with the quadrature axis voltage coupling term to obtain the target quadrature axis control voltage. Among them, the present application uses positive feedback compensation. By adding the direct axis voltage coupling term to the initial direct axis control voltage input to the motor and adding the quadrature axis voltage coupling term to the initial quadrature axis control voltage, the influence that the AC loop is too late to converge the voltage coupling term can be eliminated, and the motor achieves decoupling.

[0090] S170. Obtain the three-phase voltage control signal for input to the motor according to the target direct and quadrature axis control voltages to drive the motor to rotate.

[0091] In one embodiment, as Figure 6 shown, the target direct axis control voltage and the target quadrature axis control voltage are respectively converted back to the voltage values in the three-phase stationary coordinate system through Park inverse transformation, and then the duty ratios (Va / Vb / Vc) of the three-phase PWM (Pulse Width Modulation) signals are output through the two-level space vector modulation algorithm (Space Vector Pulse Width Modulation, SVPWM). The calculated duty ratios are sent to the inverter to generate the three-phase voltage control signal to control the operation of the motor.

[0092] Figure 7 FIG. shows a schematic structural diagram of a motor control system 200 according to an embodiment of the present application. Exemplarily, the motor control system 200 includes:

[0093] The vehicle main control module 210 is used to obtain the sensor signals in the vehicle and the three-phase current of the motor. Among them, the sensor signals include the input voltage of the motor built-in torque sensor and the real-time sampled electrical angle of the motor when the user acts on the vehicle, and the initial assist torque acting on the motor obtained based on the input voltage of the motor built-in torque sensor.

[0094] The active damping module 220 is used to perform active damping on the initial assist torque to obtain the adjusted assist torque.

[0095] The current distribution module 230 is used to determine the adjusted current of the motor according to the adjusted assist torque.

[0096] The calculation module 240 is used to calculate the feedback current of the motor according to the three-phase current and calculate the corresponding electrical angular velocity according to the electrical angle.

[0097] The current loop module 250 is configured to input the error between the regulated current and the feedback current into the current loop and output the initial direct and quadrature axis control voltages of the motor.

[0098] The decoupling module 260 is configured to determine a voltage coupling term based on the feedback current and the electrical angular velocity, and perform feedback compensation on the initial direct and quadrature axis control voltages by using the voltage coupling term to obtain the target direct and quadrature axis control voltages.

[0099] The motor drive module 270 is configured to obtain a three-phase voltage control signal for input to the motor according to the target direct and quadrature axis control voltages to drive the motor to rotate.

[0100] It can be understood that the motor control system 200 in this embodiment corresponds to the motor control method in the above embodiment. The optional items in the above embodiment are equally applicable to this embodiment, so they will not be described repeatedly here.

[0101] In several embodiments provided by the present application, it should be understood that the disclosed apparatus and method can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions, and operations of the apparatus, method, and computer program product according to multiple embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in an alternative implementation, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0102] In addition, in each embodiment of the present application, the various functional modules or units may be integrated together to form an independent part, or each module may exist alone, or two or more modules may be integrated to form an independent part.

[0103] When the above-described functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art or a part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a smart phone, a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application.

[0104] As described above, the above are only specific embodiments of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application.

Claims

1. A motor control method, characterized in that, Including: Obtaining the sensor signals in the vehicle and the three-phase current of the motor, wherein the sensor signals include the input voltage of the built-in torque sensor of the motor when the user acts on the vehicle and the motor electrical angle sampled in real time; Obtaining the initial assist torque acting on the motor based on the input voltage of the built-in torque sensor of the motor, and actively damping the initial assist torque to obtain an adjusted assist torque; wherein, before actively damping the initial assist torque to obtain the adjusted assist torque, filtering the initial assist torque through a first filter to obtain an optimized assist torque; the first filter is a first-order low-pass filter; Determining the adjusted current of the motor according to the adjusted assist torque, and calculating the feedback current of the motor according to the three-phase current; Wherein, the adjusted current of the motor includes a direct-axis adjusted current and a quadrature-axis adjusted current, and a direct-axis current control strategy or an MTPA control strategy is used to determine the direct-axis adjusted current and the quadrature-axis adjusted current; Inputting the error between the adjusted current and the feedback current into a current loop, and outputting the initial direct-axis and quadrature-axis control voltages of the motor; Calculating the corresponding electrical angular velocity according to the electrical angle, and determining a voltage coupling term based on the feedback current and the electrical angular velocity; Performing feedback compensation on the initial direct-axis and quadrature-axis control voltages by using the voltage coupling term to obtain the target direct-axis and quadrature-axis control voltages; Obtaining a three-phase voltage control signal for input to the motor according to the target direct-axis and quadrature-axis control voltages to drive the motor to rotate.

2. The motor control method according to claim 1, wherein The adjusted current includes a direct-axis adjusted current and a quadrature-axis adjusted current, the feedback current includes a direct-axis feedback current and a quadrature-axis feedback current, and inputting the error between the adjusted current and the feedback current into a current loop and outputting the initial direct-axis and quadrature-axis control voltages of the motor includes: Taking the error between the direct-axis adjusted current and the direct-axis feedback current as the first input quantity of the current loop; Taking the error between the quadrature-axis adjusted current and the quadrature-axis feedback current as the second input quantity of the current loop.

3. The motor control method according to claim 2, characterized in that, Inputting the error between the adjusted current and the feedback current into a current loop and outputting the initial direct-axis and quadrature-axis control voltages of the motor further includes: Converging the first input quantity through a direct-axis current loop to obtain an initial direct-axis control voltage; Converging the second input quantity through a quadrature-axis current loop to obtain an initial quadrature-axis control voltage.

4. The motor control method according to claim 2, wherein, Determining the voltage coupling term based on the feedback current and the electrical angular velocity includes: Calculating a direct-axis voltage coupling term according to the electrical angular velocity, the quadrature-axis inductance, and the quadrature-axis feedback current; Calculating a quadrature-axis voltage coupling term according to the electrical angular velocity, the direct-axis inductance, the magnetic flux, and the direct-axis feedback current.

5. The motor control method according to claim 4, wherein, The calculation formula for the direct-axis voltage coupling term is: （1） In Equation (1), represents the direct-axis voltage coupling term, represents the electrical angular velocity, represents the quadrature-axis inductance, represents the quadrature-axis feedback current; The calculation formula for the quadrature-axis voltage coupling term is: （2） In formula (2), represents the quadrature-axis voltage coupling term, represents the direct-axis inductance, represents the magnetic flux linkage, represents the direct-axis feedback current.

6. The motor control method according to claim 1, wherein, Actively damping the initial assist torque to obtain an adjusted assist torque includes: Inputting the electrical angular velocity into an active damper for processing and outputting a corresponding damping torque, and adjusting the optimized assist torque by using the damping torque to obtain an adjusted assist torque.

7. The motor control method according to claim 1, wherein Inputting the electrical angular velocity into the active damper for processing and outputting a corresponding damping torque includes: Filtering the electrical angular velocity through a second filter to obtain electrical angular velocity fluctuations; Calculating the damping torque according to the electrical angular velocity fluctuations and a preset damping coefficient.

8. A motor control system, characterized in that, Including: A vehicle main control module for obtaining sensor signals in the vehicle and three-phase currents of the motor, where the sensor signals include the input voltage of the motor built-in torque sensor when the user acts on the vehicle and the motor electrical angle sampled in real time, and an initial assist torque acting on the motor obtained based on the input voltage of the motor built-in torque sensor; An active damping module for actively damping the initial assist torque to obtain an adjusted assist torque; where, before actively damping the initial assist torque to obtain the adjusted assist torque, filtering the initial assist torque through a first filter to obtain an optimized assist torque; the first filter is a first-order low-pass filter; A current distribution module for determining the adjusted current of the motor according to the adjusted assist torque; where the adjusted current of the motor includes a direct-axis adjusted current and a quadrature-axis adjusted current, and a direct-axis current control strategy or an MTPA control strategy is used to determine the direct-axis adjusted current and the quadrature-axis adjusted current; A calculation module for calculating the feedback current of the motor according to the three-phase currents and calculating the corresponding electrical angular velocity according to the electrical angle; A current loop module for inputting the error between the adjusted current and the feedback current into the current loop and outputting the initial direct-axis and quadrature-axis control voltages of the motor; A decoupling module for determining a voltage coupling term based on the feedback current and the electrical angular velocity and using the voltage coupling term to perform feedback compensation on the initial direct-axis and quadrature-axis control voltages to obtain target direct-axis and quadrature-axis control voltages; A motor drive module for obtaining three-phase voltage control signals for input to the motor according to the target direct-axis and quadrature-axis control voltages to drive the motor to rotate.

9. An electric power-assisted vehicle, characterized in that, Including a motor control system, and the motor control system is used to execute the motor control method according to any one of claims 1-7.

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