Motor control method, system and electric power-assisted vehicle

Abstract

The present application relates to the field of motor control, and discloses a motor control method, system and electric power-assisted vehicle, the motor control method comprising: obtaining a sensor signal in the vehicle; obtaining an initial power-assisted torque acting on the motor based on the input voltage of the built-in torque sensor of the motor; filtering the initial power-assisted torque through a first filter to obtain an optimized power-assisted torque; calculating the corresponding electric angular velocity according to the electric angle, inputting the electric angular velocity into an active damper for processing and outputting a corresponding damping torque; adjusting the optimized power-assisted torque using the damping torque to obtain an adjusted power-assisted torque; distributing the adjusted power-assisted torque using a closed-loop control strategy to obtain a three-phase voltage control signal for inputting into the motor to drive the motor to rotate. The motor control method can solve the resonance problem caused by vehicle acceleration and deceleration, reduce motor speed fluctuations, suppress motor startup acceleration, and effectively improve riding smoothness and reduce the abrupt feeling of starting.

Description

Technical Field

[0001] The present application relates to the field of motor control technology, and in particular to a motor control method, system and electric power-assisted vehicle. Background Art

[0002] Since the beginning of the 21st century, the process of urbanization has accelerated, and traffic congestion and environmental pollution have become increasingly serious. Electric power-assisted vehicles have gradually become popular because of their environmental protection and convenience. The mid-mounted motor is an electric motor installed in the middle of the vehicle body. Due to its excellent handling and power performance, the mid-mounted motor has become an ideal choice for many high-performance electric power-assisted vehicles. The chain drive commonly used in electric power-assisted vehicles is a typical flexible connection, and the moment of inertia of the mid-mounted motor is much smaller than the moment of inertia of the whole vehicle, so resonance problems often occur during acceleration and deceleration, causing large speed fluctuations and affecting the riding experience. Moreover, during the production process, the resonant frequency of each vehicle will be different. If a notch filter is used to attenuate the specified frequency, each vehicle needs to be debugged separately, which is too much work. In addition, the mid-mounted motor is decelerated through multi-stage gears to increase the torque. Since there will be gap problems in the multi-stage gear transmission, the motor will accelerate quickly before it actually contacts the load, so there will be a strong sense of impact. Summary of the invention

[0003] In view of this, in order to solve at least one of the above problems, the embodiments of the present application provide a motor control method, system and electric power-assisted vehicle.

[0004] In a first aspect, an embodiment of the present application provides a motor control method, comprising:

[0005] Acquire sensor signals in the vehicle, including the motor built-in torque sensor input voltage and the motor electrical angle sampled in real time when the user acts on the vehicle;

[0006] Obtaining an initial assist torque acting on the motor based on an input voltage of a torque sensor built into the motor;

[0007] Filtering the initial assist torque through a first filter to obtain an optimized assist torque;

[0008] Calculate the corresponding electrical angular velocity according to the electrical angle, input the electrical angular velocity into the active damper for processing and output the corresponding damping torque;

[0009] Using the damping torque to adjust the optimized assist torque to obtain an adjusted assist torque;

[0010] The regulated assist torque is distributed using a closed-loop control strategy to obtain a three-phase voltage control signal for inputting into the motor to drive the motor to rotate.

[0011] In a first possible embodiment of the first aspect, inputting the electrical angular velocity into an active damper for processing and outputting a corresponding damping torque includes:

[0012] filtering the electrical angular velocity through a second filter to obtain electrical angular velocity fluctuation;

[0013] The damping torque is calculated according to the electrical angular velocity fluctuation and a preset damping coefficient.

[0014] In a second possible embodiment of the first aspect, the sensor signal further includes a pedal torque and a pedal revolution number, and the method further includes:

[0015] judging the vehicle state according to the pedal torque and the pedal revolutions;

[0016] determining a filter coefficient of the first filter according to the judgment result of the whole vehicle state, so that the first filter filters the initial assist torque based on the determined filter coefficient;

[0017] A filter coefficient of the second filter is determined according to the vehicle state and the pedal rotation number, so that the second filter filters the electrical angular velocity based on the determined filter coefficient.

[0018] In a third possible embodiment of the first aspect, the motor control method further includes:

[0019] It is determined whether the control system of the motor is faulty, so that when it is determined that the control system is working normally and the pedal torque or the pedal revolution number changes, the state of the whole vehicle is re-determined.

[0020] In a fourth possible embodiment of the first aspect, judging the vehicle state according to the pedal torque and the pedal revolutions includes:

[0021] When the pedal torque is greater than the preset torque and the pedal rotation number is greater than the first preset frequency, the vehicle state is determined to be a riding state, wherein the riding state includes a continuous riding state and a starting state;

[0022] When it is determined that the vehicle state is the riding state, and the pedal rotation number is greater than a second preset frequency, the vehicle state is determined to be the continuous riding state;

[0023] When it is determined that the vehicle state is the riding state, and the pedal revolution number is less than or equal to a second preset frequency, the vehicle state is determined to be the starting state;

[0024] When the pedal torque is less than or equal to the preset torque, or the pedal rotation number is less than or equal to the first preset frequency, it is determined that the vehicle state is a non-riding state.

[0025] In a fifth possible embodiment of the first aspect, determining a filter coefficient of the first filter according to a result of judging the state of the entire vehicle includes:

[0026] When the vehicle is in a starting state, setting the first filter to include a first cutoff frequency and a first filter factor;

[0027] When the vehicle state is a continuous riding state, the first filter is set to include a second cutoff frequency and a second filter factor; wherein the first cutoff frequency is less than the second cutoff frequency, and the first filter factor is less than the second filter factor.

[0028] In a sixth possible embodiment of the first aspect, determining a filter coefficient of the second filter according to the vehicle state and the pedal revolutions includes:

[0029] When the vehicle is in the starting state, the filter coefficients of the second filter corresponding to different pedal revolutions are determined by linear interpolation according to the first preset filter coefficient when the pedal revolutions are equal to the first preset frequency and the second preset filter coefficient when the pedal revolutions are equal to the second preset frequency;

[0030] Among them, the first preset filter coefficient includes a first preset cutoff frequency and a first preset filter factor, the second preset filter coefficient includes a second preset cutoff frequency and a second preset filter factor, the first preset cutoff frequency is less than the second preset cutoff frequency, and the first preset filter factor is greater than the second preset cutoff frequency.

[0031] In a seventh possible embodiment of the first aspect, the first filter is a low-pass filter, and the second filter is a high-pass filter.

[0032] In a second aspect, an embodiment of the present application provides a motor control system, including:

[0033] The vehicle main control module is used to obtain sensor signals in the vehicle, including the input voltage of the motor built-in torque sensor and the real-time sampled motor electrical angle when the user acts on the vehicle, and obtain the initial assist torque acting on the motor based on the input voltage of the motor built-in torque sensor;

[0034] A filtering module, configured to filter the initial assist torque through a first filter to obtain an optimized assist torque;

[0035] a damping module, configured to calculate a corresponding electrical angular velocity according to the electrical angle, input the electrical angular velocity into an active damper for processing and output a corresponding damping torque, and use the damping torque to adjust the optimized assist torque to obtain an adjusted assist torque;

[0036] The closed-loop control module is used to distribute the regulated assist torque using a closed-loop control strategy to obtain a three-phase voltage control signal for inputting into the motor to drive the motor to rotate.

[0037] In a third aspect, an embodiment of the present application provides an electric power-assisted vehicle, including a motor control system, wherein the motor control system is used to execute the above-mentioned motor control method.

[0038] The embodiments of the present application have the following beneficial effects:

[0039] A motor control method of this embodiment includes: obtaining sensor signals in the vehicle, including the input voltage of the motor built-in torque sensor when the user acts on the vehicle and the real-time sampled motor electrical angle; obtaining the initial power-assist torque acting on the motor based on the input voltage of the motor built-in torque sensor; filtering the initial power-assist torque through a first filter to obtain an optimized power-assist torque; calculating the corresponding electrical angular velocity according to the electrical angle, inputting the electrical angular velocity into the active damper for processing and outputting the corresponding damping torque; adjusting the optimized power-assist torque using the damping torque to obtain an adjusted power-assist torque; allocating the adjusted power-assist torque using a closed-loop control strategy to obtain a three-phase voltage control signal for input to the motor to drive the motor to rotate. This motor control method can solve the resonance problem caused by vehicle acceleration and deceleration, reduce motor speed fluctuations, suppress motor startup acceleration, and effectively improve riding smoothness and reduce the abrupt feeling of starting. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] 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 certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A schematic diagram of the structure of an electric power-assisted vehicle according to an embodiment of the present application is shown;

[0042] Figure 2 A first flow chart of the motor control method according to an embodiment of the present application is shown;

[0043] Figure 3 A second flow chart of the motor control method according to an embodiment of the present application is shown;

[0044] Figure 4 A schematic diagram showing the motor speed during vehicle acceleration in an embodiment of the present application;

[0045] Figure 5 A schematic diagram of a frequency spectrum of the motor speed during the acceleration of a vehicle in an embodiment of the present application is shown;

[0046] Figure 6 A schematic diagram showing the motor speed and motor speed fluctuation after being filtered by the first filter according to an embodiment of the present application;

[0047] Figure 7 A third flow chart of the motor control method according to an embodiment of the present application is shown;

[0048] Figure 8 A first structural schematic diagram of a motor control system according to an embodiment of the present application is shown;

[0049] Fig. 9 A second structural schematic diagram of the motor control system according to an embodiment of the present application is shown.

[0050] Description of main component symbols:

[0051] 200-motor control system; 210-vehicle main control module; 220-filter module; 230-damping module; 240-closed-loop control module; 250-nonlinear decoupling module. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0053] The components of the embodiments of the present application generally described and shown in the drawings herein may be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0054] Hereinafter, the terms "including", "having" and their cognates that can be used in various embodiments of the present application are intended only to indicate specific features, numbers, steps, operations, elements, components or a combination of the foregoing items, and should not be understood as first excluding the existence of one or more other features, numbers, steps, operations, elements, components or a combination of the foregoing items or increasing the possibility of one or more features, numbers, steps, operations, elements, components or a combination of the foregoing items. In addition, the terms "first", "second", "third" and the like are only used to distinguish descriptions and cannot be understood as indicating or implying relative importance.

[0055] Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meanings as those generally understood by those skilled in the art to which the various embodiments of the present application belong. The terms (such as those defined in generally used dictionaries) will be interpreted as having the same meanings as the contextual meanings in the relevant technical field and will not be interpreted as having idealized meanings or overly formal meanings unless clearly defined in the various embodiments of the present application.

[0056] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0057] In response to the problems of abrupt starting of current electric power-assisted vehicles and large speed fluctuations during acceleration and deceleration, the present application provides a motor control method, which filters the initial power-assisted torque through a first filter with a variable filter coefficient, and smoothly acts on the initial power-assisted torque of the motor, which not only weakens the acceleration impact caused by the gear gap in the starting stage, but also ensures the power-assisted torque response during continuous operation. The power-assisted torque is further adjusted in combination with an active damper to stabilize the speed of the motor system, eliminate the impact of starting power assistance, and improve the riding experience of the electric power-assisted vehicle.

[0058] Before describing the motor control method of the present application, the structure of the electric power-assisted vehicle is first introduced accordingly.

[0059] Figure 1A schematic diagram of the structure of an electric power-assisted vehicle proposed in an embodiment of the present application is shown. The electric power-assisted vehicle may be an electric bicycle, an electric motorcycle, an electric tricycle, and the like. Exemplarily, the main structure of the electric power-assisted vehicle includes a frame, a motor, a battery, a controller, a charger, a dashboard, a braking system, a shock absorption system, wheels, tires, and the like. The electric power-assisted vehicle also includes a motor control system, wherein a voltage control system is used to execute a motor control method, drive the motor to rotate, provide auxiliary power, reduce the driver's physical exertion, improve controllability and driving comfort, and enhance the overall driving experience. The motor control system includes a processor and a memory, wherein 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.

[0060] Among them, the processor can be an integrated circuit chip with signal processing capabilities. The processor can be a general-purpose processor, including 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 at least one of other programmable logic devices, discrete gates 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., which can implement or execute the methods, steps and logic block diagrams disclosed in the embodiments of the present application.

[0061] The memory may 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 electric erasable programmable read-only memory (EEPROM), etc. The memory is used to store a computer program, and the processor may execute the computer program accordingly after receiving an execution instruction.

[0062] The motor control method is described below in conjunction with some specific embodiments.

[0063] Figure 2A flow chart of a motor control method according to an embodiment of the present application is shown. Exemplarily, the motor control method comprises the following steps:

[0064] S110, acquiring sensor signals in the vehicle, including the input voltage of the motor's built-in torque sensor and the real-time sampled motor electrical angle when the user acts on the vehicle.

[0065] In the embodiment of the present application, the corresponding sensor signal can be obtained by multiple sensors arranged on the electric power-assisted vehicle. For example, the sensor may include but is not limited to a cadence sensor, a wheel speed sensor, a temperature sensor, an electronic brake handle, an inertial sensor, a motor built-in torque sensor and a pedal torque sensor, a magnetic encoder and an electronic throttle sensor. Among them, the cadence sensor usually collects the cadence pulse signal 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 motor built-in torque sensor is used to measure the torque output by the motor in real time to monitor and control the running state 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 convert it into the input voltage (V_sensor) of the motor built-in torque sensor. Alternatively, the position or angle change of the throttle can also be detected by the electronic throttle sensor, and converted into the input voltage (V_sensor) of the motor built-in torque sensor.

[0066] S120, obtaining an initial assist torque acting on the motor based on an input voltage of a torque sensor built into the motor.

[0067] In one embodiment, the present application analyzes and processes the input voltage of the motor's built-in torque sensor according to all the received information, including the electronic gear position and each sensor signal, through the vehicle control strategy, and outputs the corresponding initial power-assist torque (Te). Among them, the input voltage of the motor's built-in torque sensor is used to provide a working power supply for the motor's built-in torque sensor, so that it can operate normally and output an electrical signal related to the torque. The initial power-assist torque is based on the rider's manpower and provides appropriate power through the motor. Among them, different input voltages represent different electronic gear positions, and different electronic gear positions correspond to different transmission ratios or motor output characteristics. For example, in a high gear, the motor may output at a higher speed and greater torque to meet the needs of high-speed riding; in a low gear, the motor may provide a greater starting torque, which is suitable for climbing or low-speed high torque requirements.

[0068] S130, filtering the initial power assist torque through a first filter to obtain an optimized power assist torque.

[0069] For example, in view of the impact problem of acceleration and deceleration caused by gear clearance of electric power-assisted vehicles, the initial power-assisted torque is smoothed by the first filter, and the filter coefficient of the first filter is determined according to the judgment result of the vehicle state, so that the first filter filters the initial power-assisted torque based on the determined filter coefficient. Among them, the first filter is a first-order low-pass filter, which can smooth the signal, remove high-frequency noise and improve control accuracy.

[0070] In one embodiment, if Figure 3 As shown, the determination of the vehicle status includes the following steps:

[0071] S131, judging the vehicle state according to the pedal torque and the pedal revolutions.

[0072] Exemplarily, the sensor signal also includes pedal torque and pedal revolutions, wherein the pedal revolutions are the number of revolutions of the pedal per unit time, which can be determined according to the number of pedal frequency pulse signals, and the pedal frequency pulse signals can be used to monitor and control the power output of the electric power-assisted vehicle. The present application determines the vehicle state according to the pedal torque and pedal revolutions of the current electric power-assisted vehicle.

[0073] For example, in one embodiment, when the pedal torque is greater than the preset torque and the pedal revolutions are greater than the first preset frequency, the vehicle state is judged to be a riding state, wherein the riding state includes a continuous riding state and a starting state. When the vehicle state is judged to be a riding state and the pedal revolutions are greater than the second preset frequency, the vehicle state is judged to be a continuous riding state; when the vehicle state is judged to be a riding state and the pedal revolutions are less than or equal to the second preset frequency, the vehicle state is judged to be a starting state. When the pedal torque is less than or equal to the preset torque, or the pedal revolutions are less than or equal to the first preset frequency, the vehicle state is judged to be a non-riding state.

[0074] S132, judging whether the control system of the motor is faulty, so as to re-judge the state of the whole vehicle when judging that the control system is working normally and the pedal torque or the pedal revolution number changes.

[0075] In one embodiment, after the state of the whole vehicle is judged, it is judged whether the control system of the motor is in a normal working state. If the control system of the motor is in a normal working state, the state of the whole vehicle is continuously judged when the motor torque or the pedal speed changes; if the control system of the motor is in a faulty working state, the judgment of the state of the whole vehicle is terminated.

[0076] In another embodiment, when the vehicle is in the starting state, the first filter is set to include a first cutoff frequency and a first filter factor; when the vehicle is in the continuous riding state, the first filter is set to include a second cutoff frequency and a second filter factor; wherein the first cutoff frequency is less than the second cutoff frequency, and the first filter factor is less than the second filter factor. For example, the preset torque can be set to 0.5 N*m, the first preset frequency is 1, and the second preset frequency is 72. When the motor torque is greater than 1N*m and the pedaling frequency pulse signal is less than or equal to 72 counts, the vehicle is identified as in the starting state, and the first cutoff frequency of the first-order low-pass filter is set. , the first filter factor When the motor torque is greater than 1 and the pedaling frequency pulse signal is greater than 72 counts, the vehicle is identified as in continuous operation and the second cutoff frequency of the first-order low-pass filter is set. , the second filter factor It can be understood that the first-order low-pass filter with a variable filter coefficient reduces the acceleration impact caused by the gear gap during the starting phase, while ensuring the power assist torque response during continuous operation.

[0077] S140, calculating the corresponding electrical angular velocity according to the electrical angle, inputting the electrical angular velocity into the active damper for processing and outputting the corresponding damping torque.

[0078] In the embodiment of the present application, the motor speed during the acceleration of the grab vehicle is as follows: Figure 4 As shown in the figure, the motor speed fluctuates violently during acceleration, causing the rider to feel that the power assist is not smooth. The motor speed is analyzed by fast Fourier transform (FFT). Figure 5 It can be seen that the amplitude of the harmonic components within 13~20 Hz is significantly larger than the amplitude of other nearby frequency components, which indicates that there is a resonance problem in the vehicle system.

[0079] In one embodiment, in order to address the resonance problem that occurs when the vehicle system accelerates or decelerates, the present application samples the electrical angle (e_angle) of the motor through a magnetic encoder. After the magnetic encoder samples the electrical angle, it uses a frequency measurement method (M method) to count the number of pulses of the magnetic encoder within a unit time, thereby calculating the electrical angular velocity value (e_omega). The low-frequency component and the DC component are eliminated by the second filter to extract the effective electrical angular velocity fluctuation (e_omega_ac). 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. According to the conversion formula between the motor electrical angular velocity and the motor speed, the motor speed and the motor speed fluctuation can be obtained. The motor speed after filtering by the first filter is as follows: Figure 6As shown, it can be seen that the motor speed fluctuation is completely filtered out, but the original normal acceleration signal is not affected.

[0080] In another embodiment, the present application filters the electrical angular velocity through a second filter to obtain electrical angular velocity fluctuations, and determines the filter coefficient of the second filter according to the vehicle state and the number of pedal revolutions, so that the second filter filters the electrical angular velocity based on the determined filter coefficient. When the vehicle is identified as a starting state, the cutoff frequency of the second filter is gradually increased with the number of pedal revolutions to suppress the rapid acceleration action caused by the gear gap and reduce the impact caused by excessive speed changes.

[0081] In one embodiment, when the vehicle state is the starting state, the filter coefficient of the second filter corresponding to different pedal revolutions is determined by linear interpolation according to the first preset filter coefficient when the pedal revolutions are equal to the first preset frequency, and the second preset filter coefficient when the pedal revolutions are equal to the second preset frequency. Wherein, the first preset filter coefficient includes a first preset cutoff frequency and a first preset filter factor, the second preset filter coefficient includes a second preset cutoff frequency and a second preset filter factor, the first preset cutoff frequency is less than the second preset cutoff frequency, and the first preset filter factor is greater than the second preset cutoff frequency. For example, when the vehicle state is identified as the starting state, the first preset frequency is set to 1, the second preset frequency is set to 72, when the number of pedaling pulse signals is 1, the first preset cutoff frequency of the high-pass filter is set to 2 Hz, and the first preset filter factor is 0.9992; when the number of pedaling pulse signals is 72, the second preset cutoff frequency of the high-pass filter is set to 13Hz, and the second preset filter factor is 0.995; the cutoff frequencies of the high-pass filters corresponding to the remaining pedaling pulse signals can be obtained by performing linear interpolation filling.

[0082] S150, using the damping torque to adjust the optimized power-assisting torque to obtain an adjusted power-assisting torque.

[0083] In one embodiment, the motor control method determines the damping torque according to the product of the speed fluctuation obtained by filtering the second filter and the preset damping coefficient, wherein the damping torque Te_resist (N*m) = damping coefficient c (N*m*min / r) * motor speed fluctuation (r / min, revolutions per minute). The filtered power-assist torque is negatively feedback-regulated according to the damping torque to obtain the regulated power-assist torque. When the whole vehicle accelerates, the power-assist torque is appropriately reduced and optimized based on the damping torque. When the whole vehicle decelerates, the power-assist torque is appropriately increased and optimized based on the damping torque, thereby avoiding drastic fluctuations in speed during acceleration and deceleration, which causes people to perceive the power-assistance as being uneven during riding.

[0084] In an optional embodiment, the preset damping coefficient can be set to an optimal value range of [-130, -100], that is, the assist torque of the motor is reduced when the vehicle speed increases, and the input torque of the motor is increased when the vehicle speed decreases, so as to stabilize the motor speed.

[0085] S160, using a closed-loop control strategy to distribute the regulated assist torque, and obtaining a three-phase voltage control signal for inputting into the motor to drive the motor to rotate.

[0086] In one embodiment, if Figure 7 As shown in the figure, the closed-loop control strategy can use the d-axis current control strategy (Id=0) or the MTPA control strategy to determine the d-axis current reference value (Id_ref) and the q-axis current reference value (Iq_ref). The d-axis current control strategy is: according to the adjustment of the assist torque, the d-axis current reference value (Id_ref) is set to zero. The torque of the motor is completely generated by the q-axis current (Iq), so the q-axis current reference value (Iq_ref) will be set according to the required adjustment of the assist torque. The MTPA control strategy is: under a given current amplitude, by optimizing the distribution of the d-axis current reference value (Id_ref) and the q-axis current reference value (Iq_ref), the output of the assist torque can be adjusted.

[0087] In another embodiment, the d / q axis current reference value passes through the current loop PI (Proportional Integral) controller to converge the d / q axis voltage value (Vd / Vq). Vd / Vq is converted back to the voltage value in the three-phase stationary coordinate system through the Park inverse transformation, and then output as the duty cycle value (Va / Vb / Vc) of the three-phase PWM (Pulse Width Modulation) signal through the two-level space vector modulation algorithm (Space Vector Pulse Width Modulation, SVPWM), and the calculated duty cycle value is sent to the inverter to generate a three-phase PWM signal to control the operation of the motor.

[0088] Figure 8 A schematic diagram of the structure of a motor control system 200 according to an embodiment of the present application is shown. Exemplarily, the motor control system 200 includes:

[0089] The vehicle main control module 210 is used to obtain sensor signals in the vehicle, including the input voltage of the motor's built-in torque sensor and the real-time sampled motor electrical angle when the user acts on the vehicle, as well as the initial assist torque acting on the motor based on the input voltage of the motor's built-in torque sensor.

[0090] The filtering module 220 is used to filter the initial assist torque through a first filter to obtain an optimized assist torque.

[0091] The damping module 230 is used to calculate the corresponding electrical angular velocity according to the electrical angle, input the electrical angular velocity into the active damper for processing and output the corresponding damping torque, and use the damping torque to adjust the optimized assist torque to obtain the adjusted assist torque.

[0092] The closed-loop control module 240 is used to distribute the regulated assist torque using a closed-loop control strategy to obtain a three-phase voltage control signal for inputting into the motor to drive the motor to rotate.

[0093] In one embodiment, if Fig. 9 As shown, the motor control system 200 further includes: a nonlinear decoupling module 250, which is used to calculate a voltage decoupling term and compensate the voltage control signal based on the voltage decoupling term.

[0094] In one embodiment, a sampling resistor is placed at the lower end of the bridge arm to sample the three-phase current (Ia_fdk / Ib_fdk / Ic_fdk), and the Id feedback value (Id_fdk) and the Iq feedback value (Iq_fdk) are obtained through Clark transformation and Park transformation, wherein the Clark transformation is to convert the current in the three-phase coordinate system into the current in the two-phase stationary coordinate system; the Park transformation is to convert the current in the two-phase stationary coordinate system into the current in the two-phase rotating coordinate system, i.e., the Id feedback value (Id_fdk) and the Iq feedback value (Iq_fdk). Id_fdk and Iq_fdk are first given to the current loop PI controller for input error calculation; secondly, they are output to the nonlinear decoupling module 250 to calculate the voltage coupling term of the decoupling compensation, so as to solve the problem of reduced current loop bandwidth at high speed.

[0095] It can be understood that the motor control system 200 of this embodiment corresponds to the motor control method of the above embodiment, and the options in the above embodiment are also applicable to this embodiment, so they will not be described repeatedly here.

[0096] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and structure diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a 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 box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the structure diagram and / or the flow diagram, and the combination of boxes in the structure diagram and / or the flow diagram, can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0097] In addition, the functional modules or units in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0098] If the 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 the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a computer device (which can 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 the various embodiments of the present application.

[0099] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A motor control method, characterized in that: include: Acquire sensor signals in the vehicle, including the motor's built-in torque sensor input voltage, real-time sampled motor electrical angle, pedal torque, and pedal revolutions; Obtaining an initial assist torque acting on the motor based on an input voltage of a torque sensor built into the motor; judging the vehicle state according to the pedal torque and the pedal revolutions; The initial assist torque is filtered by a first filter to obtain an optimized assist torque; wherein a filter coefficient of the first filter is determined according to a result of judging the state of the whole vehicle, so that the first filter filters the initial assist torque based on the determined filter coefficient; The corresponding electrical angular velocity is calculated according to the electrical angle, and the electrical angular velocity is input into the active damper for processing and outputting the corresponding damping torque; wherein the filter coefficient of the second filter is determined according to the vehicle state and the pedal revolution number, so that the second filter filters the electrical angular velocity based on the determined filter coefficient; the electrical angular velocity is filtered by the second filter to obtain the electrical angular velocity fluctuation; the damping torque is calculated according to the electrical angular velocity fluctuation and the preset damping coefficient; Using the damping torque to adjust the optimized assist torque to obtain an adjusted assist torque; The regulated assist torque is distributed using a closed-loop control strategy to obtain a three-phase voltage control signal for inputting into the motor to drive the motor to rotate.

2. The motor control method according to claim 1, characterized in that: Also includes: It is determined whether the control system of the motor is faulty, so that when it is determined that the control system is working normally and the pedal torque or the pedal revolution number changes, the state of the whole vehicle is re-determined.

3. The motor control method according to claim 1, characterized in that: The judging of the vehicle state according to the pedal torque and the pedal revolutions includes: When the pedal torque is greater than the preset torque and the pedal rotation number is greater than the first preset frequency, the vehicle state is determined to be a riding state, wherein the riding state includes a continuous riding state and a starting state; When it is determined that the vehicle state is the riding state, and the pedal rotation number is greater than a second preset frequency, the vehicle state is determined to be the continuous riding state; When it is determined that the vehicle state is the riding state, and the pedal revolution number is less than or equal to a second preset frequency, the vehicle state is determined to be the starting state; When the pedal torque is less than or equal to the preset torque, or the pedal rotation number is less than or equal to the first preset frequency, it is determined that the vehicle state is a non-riding state.

4. The motor control method according to claim 1, characterized in that: The determining of the filter coefficient of the first filter according to the judgment result of the whole vehicle state includes: When the vehicle is in a starting state, setting the first filter to include a first cutoff frequency and a first filter factor; When the vehicle state is a continuous riding state, the first filter is set to include a second cutoff frequency and a second filter factor; wherein the first cutoff frequency is less than the second cutoff frequency, and the first filter factor is less than the second filter factor.

5. The motor control method according to claim 1, characterized in that: The determining the filter coefficient of the second filter according to the vehicle state and the pedal revolution number includes: When the vehicle is in the starting state, the filter coefficients of the second filter corresponding to different pedal revolutions are determined by linear interpolation according to the first preset filter coefficient when the pedal revolutions are equal to the first preset frequency and the second preset filter coefficient when the pedal revolutions are equal to the second preset frequency; Among them, the first preset filter coefficient includes a first preset cutoff frequency and a first preset filter factor, the second preset filter coefficient includes a second preset cutoff frequency and a second preset filter factor, the first preset cutoff frequency is less than the second preset cutoff frequency, and the first preset filter factor is greater than the second preset cutoff frequency.

6. The motor control method according to claim 1, characterized in that: The first filter is a low-pass filter, and the second filter is a high-pass filter.

7. A motor control system, characterized in that: include: The vehicle main control module is used to obtain sensor signals in the vehicle, including the input voltage of the motor built-in torque sensor when the user acts on the vehicle, the motor electrical angle, pedal torque and pedal revolutions sampled in real time; and to obtain the initial assist torque acting on the motor based on the input voltage of the motor built-in torque sensor, and to judge the vehicle state according to the pedal torque and the pedal revolutions; A filtering module, configured to filter the initial power-assist torque through a first filter to obtain an optimized power-assist torque; wherein a filter coefficient of the first filter is determined according to a result of judging the state of the entire vehicle, so that the first filter filters the initial power-assist torque based on the determined filter coefficient; A damping module, configured to calculate a corresponding electrical angular velocity according to the electrical angle, input the electrical angular velocity into an active damper for processing and output a corresponding damping torque, and use the damping torque to adjust the optimized power-assisting torque to obtain an adjusted power-assisting torque; wherein a filter coefficient of a second filter is determined according to the vehicle state and the pedal revolutions, so that the second filter filters the electrical angular velocity based on the determined filter coefficient; the electrical angular velocity is filtered by the second filter to obtain an electrical angular velocity fluctuation; and the damping torque is calculated according to the electrical angular velocity fluctuation and a preset damping coefficient; The closed-loop control module is used to distribute the regulated assist torque using a closed-loop control strategy to obtain a three-phase voltage control signal for inputting into the motor to drive the motor to rotate.

8. An electric power-assisted vehicle, characterized in that: It comprises a motor control system, and the motor control system is used to execute the motor control method according to any one of claims 1 to 6.

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