Active damping resonance suppression method and system based on disturbance observer

Abstract

The application belongs to the technical field of motor drive control, and provides an active damping resonance suppression method and system based on a disturbance observer, which is applied to a motor drive system, the motor drive system comprising a driver, an LC filter and a motor, wherein a filter inductance, a filter capacitance and a motor inductance constitute an LCL circuit; the driver voltage command and the driver output current are taken as the input of the disturbance observer to observe the filter capacitance voltage in real time; the observed filter capacitance voltage is fed back to the input end of the current loop controller after low-pass filtering and proportional link to compensate the driver output voltage command; the resonance suppression of the motor drive system is realized by adjusting the cutoff frequency of the low-pass filter and the feedback coefficient; the filter capacitance voltage is observed and fed back in real time, the system frequency characteristic is accurately corrected, the resonance is effectively suppressed, and the additional power consumption is avoided.

Description

Technical Field

[0001] This invention belongs to the field of motor drive control technology, and particularly relates to an active damped resonance suppression method and system based on a disturbance observer. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] In the field of motor drive systems, pulse width modulation (PWM) technology has become a widely used solution for achieving precise control and smooth speed regulation of AC motors. However, the high-frequency switching voltage waveform output by PWM technology contains abundant harmonic components. When these components are directly applied to the motor, they can cause problems such as increased current ripple, abnormal motor heating, and electromagnetic interference (EMI). This not only seriously affects the operating performance of the motor drive system but also shortens the service life of the motor and related components, thus restricting the long-term stable operation of the system.

[0004] To address the aforementioned issues, introducing an LC filter composed of an inductor (L) and a capacitor (C) between the driver output and the motor has become a key technical approach. This LC filter can effectively attenuate high-order harmonics in the PWM waveform, providing the motor with a near-sinusoidal terminal voltage, thereby significantly reducing current ripple, decreasing torque pulsation, and suppressing EMI, thus greatly improving the operating quality of the motor drive system.

[0005] However, the introduction of LC filters also brings new technical challenges. The filter inductor, filter capacitor, and the motor's own inductance together constitute the LCL circuit structure. Although this structure has excellent high-frequency harmonic attenuation characteristics, it will generate resonance at certain frequencies. This resonance will cause large fluctuations in motor speed, torque, and current, seriously damaging the stability and reliability of the system, becoming a core bottleneck restricting the performance improvement of motor drive systems, and urgently requiring targeted resonance suppression technology solutions.

[0006] Currently, the mainstream resonance suppression technologies in the industry are mainly divided into two categories: passive damping and active damping. Passive damping technology is a direct means of suppressing resonant spikes in LCL circuits. Its core principle is to insert damping resistors at specific locations in the LCL filter network, thereby dissipating resonant energy through the resistors to achieve resonance suppression. Depending on the placement of the damping resistors, passive damping topologies can be divided into various types, such as filter inductor series resistor, filter inductor parallel resistor, motor inductor series resistor, motor inductor parallel resistor, filter capacitor series resistor, filter capacitor parallel resistor, and other derived complex circuit structures.

[0007] Among them, the topology scheme of filter capacitor in parallel with resistor performs best. This scheme only changes the system characteristics near the resonant frequency, and has almost no impact on low-frequency gain and high-frequency harmonic attenuation capability, resulting in the most ideal damping effect. However, passive damping technology has significant drawbacks: the high-frequency harmonic energy output by the driver is dissipated as heat through the damping resistor, causing the damping resistor to heat up severely. This not only reduces the system operating efficiency, but also requires an additional filter heat dissipation system, increasing the system's size, weight, and cost, making it unsuitable for applications with high requirements for size and efficiency.

[0008] To improve the shortcomings of passive damping, researchers have modified the damping network topology by adding bypass inductors, bypass capacitors, or splitting capacitors to reduce the power loss of the damping resistor. However, this does not fundamentally solve the energy loss problem and has limited applicability.

[0009] Active damping technology achieves resonance suppression by modifying system characteristics through control algorithms, avoiding the energy loss problem of passive damping, and has become a research hotspot in current resonance suppression technology. This technology is mainly divided into two categories: filter-based schemes and state feedback-based schemes.

[0010] The core of filter-based active damping schemes is to insert a digital filter with specific functions into the forward path of the current control loop to attenuate the system's resonant peak value. Commonly used digital filters include: Low-pass filters (LPFs), which achieve a balance between control bandwidth and system stability margin by selecting a cutoff frequency, and utilize the phase lag caused by the LPF to provide damping for the system, shifting the phase curve towards the stable frequency range. However, a lower cutoff frequency can severely limit the system bandwidth and reduce the system's dynamic performance. Notch filters (NFs): When the center frequency of the NF coincides with the system's resonant frequency, its anti-resonant peak value can cancel out the resonant peak value of the LC filter, achieving resonance suppression based on the zero-pole cancellation principle. This scheme has good damping effect and is simple to implement, but it is sensitive to changes in the resonant frequency and can easily lead to insufficient low-frequency phase margin of the system. All-pass filters (APFs) work similarly to LPFs, expanding the system's phase margin at the resonant frequency through the phase lag caused by the APF, but simultaneously reducing the system's dynamic performance and robustness.

[0011] To address the issue of notch filters being sensitive to frequency variations, robust notch filters have been proposed, which perform particularly well in dual-resonance scenarios, effectively improving the system's adaptability to parameter changes.

[0012] Active damping schemes based on state feedback correct frequency characteristics and suppress resonance by precisely feeding back system state variables. The core feedback state variables include capacitor voltage and capacitor current. Different state feedback methods correspond to different system control block diagrams: Proportional feedback of capacitor current: effectively suppresses amplitude spikes at the resonant frequency, ensuring system stability. Its effect is equivalent to a passive damping scheme with a filter capacitor and parallel resistor, without energy loss. Differential feedback of capacitor voltage: the principle of damping is the same as with a filter capacitor and parallel resistor, but the differential element is sensitive to noise, easily inducing additional resonance or even causing system instability. It needs to be used in conjunction with a filter or a lead-lag network, increasing system complexity.

[0013] In recent years, new active damping strategies have emerged, such as the scheme based on the combination of linear active disturbance rejection control and fuzzy adaptive control, which further improves the robustness of the system under the scenario of power grid impedance change and provides more technical options for the resonance suppression of motor drive system. However, there are still some areas for optimization in the existing technology, such as stability under complex working conditions and the simplicity of control algorithm. Continuous improvement is needed to meet the application requirements of higher performance. Summary of the Invention

[0014] To overcome the shortcomings of the prior art, this invention provides an active damped resonance suppression method and system based on a disturbance observer. By observing and feeding back the voltage of the filter capacitor in real time, the system frequency characteristics are accurately corrected, effectively suppressing resonance while avoiding additional power consumption.

[0015] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides an active damped resonance suppression method based on a disturbance observer, the method being applied to a motor drive system, the motor drive system including a driver, an LC filter, and a motor, wherein the filter inductor, the filter capacitor, and the motor inductor constitute an LCL circuit; the method includes: The voltage of the filter capacitor is observed in real time using the driver voltage command and the driver output current as inputs to the disturbance observer. The observed filter capacitor voltage is passed through a low-pass filter and a proportional circuit, and then fed back to the input of the current loop controller to compensate for the driver output voltage command. Resonance suppression in the motor drive system can be achieved by adjusting the cutoff frequency and feedback coefficient of the low-pass filter.

[0016] Furthermore, the observed filter capacitor voltage is expressed as: in, oh c This is the cutoff frequency of a first-order low-pass filter; V ref (s () is the driver output voltage command; K c This is the capacitor voltage feedback coefficient; L f This is the filter inductor.

[0017] Furthermore, the frequency and amplitude at the common intersection are calculated based on the transfer function from the driver-side current to the driver output voltage command, and the cutoff frequency of the corresponding low-pass filter is calculated based on the calculated frequency and amplitude at the common intersection.

[0018] Furthermore, the determination of the cutoff frequency of the low-pass filter is specifically as follows: ; ; B =(1- K c ) L / L f ; in, L For motor inductance, L f For filter inductance; K c This is the capacitor voltage feedback coefficient; This is the resonant frequency of the motor drive system.

[0019] Furthermore, the resonant frequency of the motor drive system is calculated based on its transfer function, specifically: ; in, L For motor inductance, L f For filter inductance, C f This is the filter capacitor.

[0020] Furthermore, the observed filter capacitor voltage is fed back to the input of the current loop controller after passing through a low-pass filter and a proportional circuit. The transfer function from the driver-side current to the driver output voltage command can be expressed as follows: in, I i ( s () represents the driver-side current; V ref ( s () is the driver output voltage command; L For motor inductance, L fFor filter inductance, C f This is the filter capacitor.

[0021] Furthermore, a low-pass filter is introduced to process the observed filter capacitor voltage, and then the voltage is fed back to the input of the current loop controller proportionally.

[0022] Secondly, the present invention provides an active damped resonance suppression system based on a disturbance observer, applied to a motor drive system. The motor drive system includes a driver, an LC filter, and a motor, wherein the filter inductor, filter capacitor, and motor inductor constitute an LCL circuit; the active damped resonance suppression system includes: The disturbance observation module is configured to use the driver voltage command and the driver output current as inputs to the disturbance observer to observe the filter capacitor voltage in real time. The feedback module is configured to feed back the observed filter capacitor voltage to the input of the current loop controller after passing it through a low-pass filter and a proportional circuit to compensate for the driver output voltage command. The adjustment module is configured to suppress resonance in the motor drive system by adjusting the cutoff frequency and feedback coefficient of the low-pass filter.

[0023] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0024] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0025] The above one or more technical solutions have the following beneficial effects: In this invention, a virtual active damping is constructed through a disturbance observer and voltage feedback, eliminating the need for physical damping resistors. This avoids the problem of high-frequency harmonic energy being dissipated as heat through resistors in passive damping, completely eliminating additional power loss and improving overall system efficiency. It is particularly suitable for high-power motor drive scenarios, such as industrial servos and new energy vehicle drives, reducing the design pressure on the heat dissipation system and lowering energy consumption. Furthermore, the disturbance observer only relies on existing measurable signals in the system, eliminating the need for additional capacitor voltage sensors and motor-side current sensors, thus reducing hardware procurement costs and wiring complexity.

[0026] In this invention, by optimizing the cutoff frequency of the low-pass filter and the capacitor voltage feedback coefficient, the system amplitude can be suppressed to below 0dB at the resonant frequency, completely solving the problems of speed fluctuation and torque pulsation caused by LCL circuit resonance, and ensuring that the motor can still run smoothly under dynamic conditions such as start-up, stop, and sudden load changes.

[0027] In this invention, the capacitor voltage is observed without hysteresis through a disturbance observer, and the feedback compensation is timely. This avoids the limitation of system bandwidth caused by the phase hysteresis introduced by the filter, and takes into account both resonance suppression and dynamic response speed.

[0028] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0029] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0030] Figure 1 This is a block diagram of the active damped resonance suppression method based on a disturbance observer in an embodiment of the present invention; Figure 2 This is the steady-state waveform without resonance suppression in this embodiment of the invention; Figure 3 This is the steady-state waveform when the resonance suppression method is added in an embodiment of the present invention. Detailed Implementation

[0031] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0032] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0033] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0034] Example 1 This embodiment discloses an active damped resonance suppression method based on a disturbance observer, applied to a motor drive system. The motor drive system includes a driver, an LC filter, and a motor, wherein the filter inductor, filter capacitor, and motor inductor constitute an LCL circuit; including: The voltage of the filter capacitor is observed in real time using the driver voltage command and the driver output current as inputs to the disturbance observer. The observed filter capacitor voltage is passed through a low-pass filter and a proportional circuit, and then fed back to the input of the current loop controller to compensate for the driver output voltage command. Resonance suppression in the motor drive system can be achieved by adjusting the cutoff frequency and feedback coefficient of the low-pass filter.

[0035] This embodiment constructs virtual active damping through a disturbance observer and voltage feedback, eliminating the need for physical damping resistors. This avoids the problem of high-frequency harmonic energy dissipating as heat through resistors in passive damping, completely eliminating additional power loss and improving overall system efficiency. It is particularly suitable for high-power motor drive scenarios, such as industrial servos and new energy vehicle drives, reducing the design pressure on the cooling system and lowering energy consumption. Furthermore, the disturbance observer only relies on existing measurable signals in the system, eliminating the need for additional capacitor voltage sensors and motor-side current sensors, thus reducing hardware procurement costs and wiring complexity.

[0036] like Figure 1 As shown, this method uses the driver voltage command and driver output current as inputs to a disturbance observer to monitor the filter capacitor voltage in real time and feeds it back to the current loop input to compensate for the driver output voltage. The core of the disturbance observer consists of a cutoff frequency of ω. c A low-pass filter with a gain of K c / K P The feedback loop and a gain of K P It consists of a proportional compensation process.

[0037] This embodiment constructs a motor drive system including an LC output filter. The motor drive system includes a driver, an LC filter, and a motor, wherein the filter inductor... L f Filter capacitor C f With motor inductance L An LCL circuit is constructed; the resonant frequency of the system is calculated based on the transfer function of the motor drive system; a disturbance observer is designed to observe the voltage of the filter capacitor in real time, using the driver voltage command and the driver output current as inputs; the observed capacitor voltage is fed back to the input of the current loop controller after passing through a low-pass filter and a proportional circuit to compensate for the driver output voltage command; the system damping effect is optimized by adjusting the cutoff frequency and feedback coefficient of the low-pass filter, so that the amplitude at the resonant frequency is lower than 0dB, ensuring stable system operation.

[0038] The following is combined with Figure 1 The active damped resonance suppression method based on a disturbance observer proposed in this embodiment is described in detail below: Step 1: Construct a motor drive system including an LC output filter. The motor drive system includes a driver, an LC filter, and a motor, wherein the filter inductor...L f Filter capacitor C f With motor inductance L Constructing an LCL circuit, For current command, I ref ( s () is the current reference value. I c ( s ) represents capacitance. e ( s ) represents the back electromotive force of the motor. I q ( s ) is an electric motor q shaft current, R This is the motor resistance.

[0039] The motor drive system in step 1 can be represented as: in, I i ( s ( ) represents the motor current. I inv ( s ) represents the driver output current. L For motor inductance, L f For filter inductance, C f For filter capacitors, oh res It is the resonant frequency.

[0040] Step 2: Calculate the resonant frequency of the motor drive system based on the motor drive system transfer function.

[0041] The resonant frequency in step 2 can be expressed as: in, L For motor inductance, L f For filter inductance; C f This is the filter capacitor.

[0042] Step 3: Design a disturbance observer to observe the filter capacitor voltage in real time using the driver voltage command and driver output current as inputs.

[0043] The capacitor voltage observed in step 3 can be expressed as: in, ohc This is the cutoff frequency of a first-order low-pass filter; This is the capacitor voltage feedback coefficient; For driver voltage command; L f For filter inductance; K P For driver gain.

[0044] Step 4: After the observed capacitor voltage is passed through a low-pass filter and a proportional circuit, it is fed back to the input of the current loop controller to compensate for the driver output voltage command.

[0045] Driver-side current in step 4 I i ( s ) to driver output voltage command V ref ( s The transfer function of ) can be expressed as Step 5: Adjust the cutoff frequency of the low-pass filter. oh c and capacitor voltage feedback coefficient The system damping effect is optimized to ensure that the amplitude at the resonant frequency is below 0dB, thus ensuring stable system operation.

[0046] In step 5, the cutoff frequency of the low-pass filter is... oh c and capacitor voltage feedback coefficient To carry out the design.

[0047] The frequency at the common intersection can be calculated based on the transfer function in step 4. oh 0 and amplitude | G IiV ( oh 0)|: in, The resonant frequency, A = L / L f , B =(1- K c ) L / L f .

[0048] Based on the frequency at the common intersection oh 0 and amplitude | GIiV ( oh 0) | Calculate the corresponding low-pass filter cutoff frequency oh c : in, It is the resonant frequency.

[0049] Based on the driver-side current I i ( s ) to driver output voltage command V ref ( s The transfer function of ) changes with the capacitor voltage feedback coefficient. K c As the capacitance increases, the resonant peak value of the amplitude curve gradually decreases. Increasing the capacitor voltage feedback coefficient... K c At the same time, it is necessary to increase the cutoff frequency of the low-pass filter. oh c This ensures optimal suppression of resonance spikes.

[0050] This embodiment addresses the LCL circuit resonance problem caused by the introduction of an LC output filter in a motor drive system. It constructs a disturbance observer, using the driver voltage command and output current as inputs, to monitor the filter capacitor voltage in real time. The observed value is then low-pass filtered and proportionally controlled before being fed back to the input of the current loop controller. This introduces active damping at the system's resonant frequency, effectively suppressing resonance spikes and restoring system stability. This embodiment eliminates the need for physical damping resistors, avoiding additional power losses. Furthermore, by optimizing the cutoff frequency and feedback coefficient of the low-pass filter, optimal resonance suppression is achieved over a wide operating range. Experiments show that this method significantly improves system performance, transforming the motor terminal voltage from a square wave to a sine wave, and significantly reducing the total harmonic distortion rate of line voltage and phase current, thus achieving efficient and stable sinusoidal drive of the motor.

[0051] This embodiment is particularly suitable for high-switching-frequency motor drive systems, effectively suppressing resonance peaks introduced by the LC output filter. By observing and feeding back the capacitor voltage to the control system in real time, this method reshapes the system's frequency characteristics, successfully suppressing amplitude spikes at the resonance point below 0dB, thus ensuring global system stability. Experimental results show that this method can optimize the motor terminal voltage from a pulse waveform to a sinusoidal waveform, significantly reducing the THD (Total Harmonic Distortion) of line voltage and phase current. Under various dynamic operating conditions, the system's speed and torque fluctuations are also greatly reduced, resulting in a comprehensive improvement in overall performance.

[0052] Example 2 The purpose of this embodiment is to provide an active damped resonance suppression system based on a disturbance observer, applied to a motor drive system. The motor drive system includes a driver, an LC filter, and a motor, wherein the filter inductor, filter capacitor, and motor inductor constitute an LCL circuit. The active damped resonance suppression system includes: The disturbance observation module is configured to use the driver voltage command and the driver output current as inputs to the disturbance observer to observe the filter capacitor voltage in real time. The feedback module is configured to feed back the observed filter capacitor voltage to the input of the current loop controller after passing it through a low-pass filter and a proportional circuit to compensate for the driver output voltage command. The adjustment module is configured to suppress resonance in the motor drive system by adjusting the cutoff frequency and feedback coefficient of the low-pass filter.

[0053] In further embodiments, the following is also provided: A server that can be used to execute the methods provided in the above embodiments. Specifically: A server includes a Central Processing Unit (CPU), system memory comprising Random Access Memory (RAM) and Read Only Memory (ROM), and a system bus connecting the system memory and the CPU. The server also includes a basic input / output system (I / O system) to facilitate information transfer between various components within the computer, and mass storage devices for storing the operating system, applications, and other program modules.

[0054] A basic input / output system includes a display for showing information and input devices such as a mouse and keyboard for user input. Both the display and the input devices are connected to the central processing unit via an input / output controller connected to the system bus. The basic input / output system may also include an input / output controller for receiving and processing input from multiple other devices such as a keyboard, mouse, or electronic stylus. Similarly, the input / output controller also provides output to a display screen, printer, or other types of output devices.

[0055] Mass storage devices are connected to the central processing unit via a mass storage controller (not shown) connected to the system bus. The mass storage devices and their associated computer-readable media provide non-volatile storage for the server. That is, mass storage devices may include computer-readable media (not shown) such as hard disks or CD-ROM (CompactDisc Read-Only Memory) drives.

[0056] Computer-readable media can include computer storage media and communication media. Computer storage media includes volatile and non-volatile, removable and non-removable media implemented using any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media include RAM, ROM, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), flash memory or other solid-state storage technologies, CD-ROM, DVD (Digital Versatile Disc) or other optical storage, magnetic tape cassettes, magnetic tape, disk storage, or other magnetic storage devices. Of course, those skilled in the art will understand that computer storage media are not limited to the above-mentioned types. The aforementioned system memories and mass storage devices can be collectively referred to as memory.

[0057] According to various embodiments of the present invention, the server can also connect to and operate on a remote computer on a network such as the Internet. That is, the server can connect to the network through a network interface unit connected to the system bus, or it can use a network interface unit to connect to other types of networks or remote computer systems (not shown).

[0058] The aforementioned memory also includes one or more programs, which are stored in the memory and configured to be executed by the CPU.

[0059] One embodiment provides a terminal that can be used to perform the methods provided in the above embodiments. The terminal may be a portable mobile terminal, such as a smartphone, tablet computer, MP3 player (Moving Picture Experts Group Audio Layer III), MP4 player (Moving Picture Experts Group Audio Layer IV), laptop computer, or desktop computer. The terminal may also be referred to by other names such as user terminal, portable terminal, laptop terminal, desktop terminal, etc.

[0060] Typically, a terminal includes a processor and memory.

[0061] The processor may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor may be implemented using at least one of the following hardware forms: DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), or PLA (Programmable Logic Array). The processor may also include a main processor and coprocessors. The main processor, also known as the CPU (Central Processing Unit), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, the processor may integrate a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, the processor may also include an AI (Artificial Intelligence) processor, which handles computational operations related to machine learning.

[0062] The memory may include one or more computer-readable storage media, which may be non-transitory. The memory may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In some embodiments, the non-transitory computer-readable storage media in the memory are used to store at least one instruction, which is executed by a processor to implement the sound reverberation method provided in the method embodiments of this application.

[0063] In some embodiments, the terminal may also optionally include: a peripheral device interface and at least one peripheral device. The processor, memory, and peripheral device interface can be connected via a bus or signal line. Each peripheral device can be connected to the peripheral device interface via a bus, signal line, or circuit board. Specifically, the peripheral device includes at least one of: a radio frequency circuit, a display screen, a camera assembly, an audio circuit, a positioning assembly, or a power supply.

[0064] Peripheral device interfaces can be used to connect at least one I / O (Input / Output) related peripheral device to the processor and memory. In some embodiments, the processor, memory, and peripheral device interface are integrated on the same chip or circuit board; in some other embodiments, any one or two of the processor, memory, and peripheral device interface can be implemented on separate chips or circuit boards, which is not limited in this embodiment.

[0065] Radio frequency (RF) circuits are used to receive and transmit RF signals, also known as electromagnetic signals. RF circuits communicate with communication networks and other communication devices via electromagnetic signals. RF circuits convert electrical signals into electromagnetic signals for transmission, or convert received electromagnetic signals back into electrical signals. Optionally, RF circuits include: antenna systems, RF transceivers, one or more amplifiers, tuners, oscillators, digital signal processors, codec chipsets, user identity module cards, etc. RF circuits can communicate with other terminals through at least one wireless communication protocol. These wireless communication protocols include, but are not limited to: the World Wide Web, metropolitan area networks, intranets, various generations of mobile communication networks (2G, 3G, 4G, and 5G), wireless local area networks, and / or WiFi (Wireless Fidelity) networks. In some embodiments, the RF circuit may also include circuitry related to NFC (Near Field Communication), which is not limited in this application.

[0066] The display screen is used to display the UI (User Interface). This UI can include graphics, text, icons, videos, and any combination thereof. When the display screen is a touch screen, it also has the ability to collect touch signals on or above the surface of the display. These touch signals can be input as control signals to a processor for processing. In this case, the display screen can also be used to provide virtual buttons and / or a virtual keyboard, also known as soft buttons and / or a soft keyboard. In some embodiments, there can be one display screen, which serves as the front panel of the terminal; in other embodiments, there can be at least two display screens, respectively disposed on different surfaces of the terminal or in a folded design; in still other embodiments, the display screen can be a flexible display screen, disposed on a curved or folded surface of the terminal. Furthermore, the display screen can be configured as a non-rectangular, irregular shape, i.e., a non-rectangular screen. The display screen can be made of materials such as LCD (Liquid Crystal Display) and OLED (Organic Light-Emitting Diode).

[0067] A camera assembly is used to capture images or videos. Optionally, the camera assembly includes a front-facing camera and a rear-facing camera. Typically, the front-facing camera is located on the front panel of the terminal, and the rear-facing camera is located on the back of the terminal. In some embodiments, there are at least two rear-facing cameras, which are any one of a main camera, a depth-sensing camera, a wide-angle camera, and a telephoto camera, to achieve background blurring by fusion of the main camera and the depth-sensing camera, panoramic shooting by fusion of the main camera and the wide-angle camera, VR (Virtual Reality) shooting, or other fusion shooting functions. In some embodiments, the camera assembly may also include a flash. The flash can be a single-color temperature flash or a dual-color temperature flash. A dual-color temperature flash refers to a combination of a warm-light flash and a cool-light flash, which can be used for light compensation at different color temperatures.

[0068] The audio circuitry may include a microphone and a speaker. The microphone is used to collect sound waves from the user and the environment, converting them into electrical signals that are input to a processor for processing, or to radio frequency (RF) circuitry for voice communication. For stereo sound acquisition or noise reduction purposes, multiple microphones may be used, positioned at different locations on the terminal. The microphone may also be an array microphone or an omnidirectional microphone. The speaker is used to convert electrical signals from the processor or RF circuitry into sound waves. The speaker may be a traditional diaphragm speaker or a piezoelectric ceramic speaker. When the speaker is a piezoelectric ceramic speaker, it can convert electrical signals not only into audible sound waves but also into inaudible sound waves for purposes such as distance measurement. In some embodiments, the audio circuitry may also include a headphone jack.

[0069] The positioning component is used to determine the current geographical location of the terminal to enable navigation or LBS (Location Based Service). The positioning component can be based on the US GPS (Global Positioning System), China's BeiDou system, or Russia's Galileo system.

[0070] The power supply is used to power the various components in the terminal. The power supply can be alternating current (AC), direct current (DC), a disposable battery, or a rechargeable battery. When the power supply includes a rechargeable battery, it can be a wired or wirelessly rechargeable battery. A wired rechargeable battery is charged via a wired connection, while a wirelessly rechargeable battery is charged via a wireless coil. The rechargeable battery can also be used to support fast charging technology.

[0071] In some embodiments, the terminal further includes one or more sensors. These one or more sensors include, but are not limited to, accelerometers, gyroscopes, pressure sensors, fingerprint sensors, optical sensors, and proximity sensors.

[0072] An accelerometer can detect the magnitude of acceleration along the three axes of a coordinate system established by the terminal. For example, an accelerometer can be used to detect the components of gravitational acceleration along the three axes. The processor can then control the touchscreen to display the user interface in either landscape or portrait view based on the gravitational acceleration signals acquired by the accelerometer. Accelerometers can also be used for collecting motion data in games or for other applications.

[0073] The gyroscope sensor can detect the terminal's orientation and rotation angle. It can work in conjunction with an accelerometer to capture the user's 3D movements on the terminal. Based on the data collected by the gyroscope sensor, the processor can perform the following functions: motion sensing (e.g., changing the UI based on the user's tilt), image stabilization during shooting, game control, and inertial navigation.

[0074] The pressure sensor can be located on the side bezel of the terminal and / or under the touchscreen display. When the pressure sensor is located on the side bezel, it can detect the user's grip signal on the terminal, and the processor can perform left / right hand recognition or quick operation based on the grip signal collected by the pressure sensor. When the pressure sensor is located under the touchscreen display, the processor can control the operable controls on the UI interface based on the user's pressure on the touchscreen display. Operable controls include at least one of button controls, scroll bar controls, icon controls, or menu controls.

[0075] A fingerprint sensor is used to collect a user's fingerprint. The processor identifies the user based on the fingerprint collected by the sensor, or vice versa. When the user's identity is verified as trusted, the processor authorizes the user to perform relevant sensitive operations, including unlocking the screen, viewing encrypted information, downloading software, making payments, and changing settings. The fingerprint sensor can be located on the front, back, or side of the terminal. When the terminal has physical buttons or a manufacturer's logo, the fingerprint sensor can be integrated with those buttons or the logo.

[0076] An optical sensor is used to collect ambient light intensity. In one embodiment, the processor can control the display brightness of the touch screen based on the ambient light intensity collected by the optical sensor. Specifically, when the ambient light intensity is high, the display brightness of the touch screen is increased; when the ambient light intensity is low, the display brightness of the touch screen is decreased. In another embodiment, the processor can also dynamically adjust the shooting parameters of the camera assembly based on the ambient light intensity collected by the optical sensor.

[0077] A proximity sensor, also known as a distance sensor, is typically located on the front panel of a terminal. It is used to detect the distance between the user and the front of the terminal. In one embodiment, when the proximity sensor detects that the distance between the user and the front of the terminal is gradually decreasing, the processor controls the touchscreen display to switch from a screen-on state to a screen-off state; conversely, when the proximity sensor detects that the distance between the user and the front of the terminal is gradually increasing, the processor controls the touchscreen display to switch from a screen-off state to a screen-on state.

[0078] Those skilled in the art will understand that the structure shown does not constitute a limitation on the terminal, and may include more or fewer components than shown, or combine certain components, or employ different component arrangements.

[0079] An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When executed by the processor, the computer instructions perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0080] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0081] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0082] A computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in Embodiment 1.

[0083] The method in Embodiment 1 can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method.

[0084] The computer storage medium of this embodiment can be any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. For example, a computer-readable storage medium can be—but is not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of computer-readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0085] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of sending, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device.

[0086] The program code contained on a computer-readable medium may be transmitted using any suitable medium, including—but not limited to—wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0087] Computer program code for performing the operations of this invention can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as "C" or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0088] A computer program product includes a computer program that, when executed by a processor, implements the method described in Embodiment 1.

[0089] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0090] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0091] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0092] Those skilled in the art will recognize that the units and algorithm steps described in conjunction with the embodiments herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0093] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. An active damped resonance suppression method based on a disturbance observer, characterized in that, The method is applied to a motor drive system, which includes a driver, an LC filter, and a motor, wherein the filter inductor, filter capacitor, and motor inductor constitute an LCL circuit; the method includes: The voltage of the filter capacitor is observed in real time using the driver voltage command and the driver output current as inputs to the disturbance observer. The observed filter capacitor voltage is passed through a low-pass filter and a proportional circuit, and then fed back to the input of the current loop controller to compensate for the driver output voltage command. Resonance suppression in the motor drive system can be achieved by adjusting the cutoff frequency and feedback coefficient of the low-pass filter.

2. The active damped resonance suppression method based on a disturbance observer as described in claim 1, characterized in that, The observed filter capacitor voltage is expressed as: in, ω c This is the cutoff frequency of a first-order low-pass filter; V ref ( s () is the driver output voltage command; K c This is the capacitor voltage feedback coefficient; L f This is the filter inductor.

3. The active damped resonance suppression method based on a disturbance observer as described in claim 1, characterized in that, The frequency and amplitude at the common junction are calculated based on the transfer function from the driver-side current to the driver output voltage command. The cutoff frequency of the corresponding low-pass filter is then calculated based on the calculated frequency and amplitude at the common junction.

4. The active damped resonance suppression method based on a disturbance observer as described in claim 3, characterized in that, The cutoff frequency of the low-pass filter is determined as follows: ； ； B =（1- K c ） L / L f ； in, L For motor inductance, L f For filter inductance; K c This is the capacitor voltage feedback coefficient; This is the resonant frequency of the motor drive system.

5. The active damped resonance suppression method based on a disturbance observer as described in claim 4, characterized in that, The resonant frequency of the motor drive system is calculated based on its transfer function. ； in, L For motor inductance, L f For filter inductance, C f This is the filter capacitor.

6. The active damped resonance suppression method based on a disturbance observer as described in claim 3, characterized in that, The observed filter capacitor voltage is fed back to the input of the current loop controller after passing through a low-pass filter and a proportional circuit. The transfer function from the driver-side current to the driver output voltage command can be expressed as follows: in, I i ( s () represents the driver-side current; V ref ( s () is the driver output voltage command; L For motor inductance, L f For filter inductance, C f This is the filter capacitor.

7. The active damped resonance suppression method based on a disturbance observer as described in claim 1, characterized in that, A low-pass filter is introduced to process the observed filter capacitor voltage, and then the voltage is fed back to the input of the current loop controller proportionally.

8. An active damped resonance suppression system based on a disturbance observer, characterized in that, This system is applied to a motor drive system, which includes a driver, an LC filter, and a motor, wherein the filter inductor, filter capacitor, and motor inductor constitute an LCL circuit; the active damping resonance suppression system includes: The disturbance observation module is configured to use the driver voltage command and the driver output current as inputs to the disturbance observer to observe the filter capacitor voltage in real time. The feedback module is configured to feed back the observed filter capacitor voltage to the input of the current loop controller after passing it through a low-pass filter and a proportional circuit to compensate for the driver output voltage command. The adjustment module is configured to suppress resonance in the motor drive system by adjusting the cutoff frequency and feedback coefficient of the low-pass filter.

9. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in any one of claims 1-7.

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