61 results about "Shaft voltage" patented technology

The application discloses a motor control method, a controller, a motor, a refrigerator, a medium and a program product. A direct-current bus voltage and a cross-axis current of a motor are acquired, and a direct-axis voltage and a cross-axis voltage are acquired. An initial direct-axis current is generated through field weakening control according to the direct-axis voltage, the cross-axis voltage and the direct-current bus voltage. A target frequency disturbance component caused by direct-current bus voltage fluctuation and a direct-current component used for field weakening control are separated from the initial direct-axis current. A phase of the target frequency disturbance component is calculated and optimized to obtain a target alternating current component, with minimization of a harmonic component of the target frequency in the cross-axis current as an optimization target. A direct-axis reference current is synthesized according to the target alternating current component and the direct-current component, and the motor is controlled according to the direct-axis reference current. In the working condition of the direct-current bus voltage fluctuation, energy backflow can be effectively inhibited, current harmonics can be reduced, torque pulsation can be reduced, and the running stability of the motor can be improved.

This application discloses a motor harmonic suppression method based on parallel PR controllers. The method includes: acquiring the real-time speed of the motor, the D-axis error current, and the Q-axis error current; determining the switching status of each PR controller based on the real-time speed and the corresponding lower and upper speed limits; inputting the D-axis error current and Q-axis error current into the activated PR controller to obtain the D-axis harmonic compensation voltage and Q-axis harmonic compensation voltage; inputting the D-axis error current and Q-axis error current into the corresponding D-axis current loop controller and Q-axis current loop controller to obtain the D-axis voltage and Q-axis voltage; adding the D-axis harmonic compensation voltage and the D-axis voltage to obtain the D-axis target voltage; adding the Q-axis harmonic compensation voltage and the Q-axis voltage to obtain the Q-axis target voltage; and generating a control signal for driving the motor based on the D-axis target voltage and the Q-axis target voltage. This effectively reduces torque ripple and noise caused by motor current harmonics.

The application belongs to the technical field of motor control, and relates to a kind of air conditioner compressor rotating speed fast observation method and system, the method comprises: three-phase current of motor is transformed into dq axis current actual value;PI is carried out PI adjustment to the difference between motor rotating speed given value and motor rotating speed actual value, and q axis current given value is obtained, and the difference between q axis current given value and q axis current actual value is carried out PI adjustment to obtain q axis voltage given value;The difference between d axis current given value and d axis current actual value is carried out PI adjustment to obtain d axis voltage given value;Dq axis voltage given value is transformed into alpha axis voltage given value;Based on alpha axis voltage given value and the output voltage of frequency as motor rotating speed observation value, the updated motor rotating speed observation value is obtained.The application can realize stable observation of motor rotating speed in full speed range, and the observation result is accurate, especially when motor rotating speed dynamically changes, excellent dynamic tracking effect can be realized.

A transmission characteristic parameter identification method for a ball screw feeding system comprises the following steps: in the normal operation process of the ball screw feeding system, acquiring voltage, current, rotating speed and other signals through a servo motor and a driving system thereof, and realizing online identification of key electromagnetic parameters and mechanical parameters in stages; under the static working condition of the motor, controlled voltage excitation is applied, stator current is measured, and identification of stator winding resistance and stator inductance is completed; under the steady-state operation condition, the flux linkage amplitude of the permanent magnet is calculated based on a q-axis voltage equation; under a dynamic operation condition, a friction torque model is established through segmented constant-speed operation, a rotor motion equation is combined, a recursive least square algorithm with a forgetting factor is introduced, and online identification of the equivalent rotational inertia of the system is realized; according to the method, complete and accurate transmission characteristic parameters can be obtained in the ball screw feeding system, the identification process is stable, the calculation complexity is low, and the method is suitable for being embedded into a servo control system.

This application provides a method, apparatus, and electronic device for suppressing the influence of common-mode voltage and achieving midpoint potential balance. The method includes: acquiring the voltage difference between the positive and negative DC bus, the grid phase, the direct-axis inductor current and the quadrature-axis inductor current, and the direct-axis voltage component and the quadrature-axis voltage component; modulating the direct-axis voltage component and the quadrature-axis voltage component based on the direct-axis inductor current and the quadrature-axis inductor current to obtain a three-phase initial modulation reference voltage; performing compensation analysis on the voltage difference between the positive and negative bus to obtain a target compensation signal; compensating the three-phase initial modulation reference voltage using the target compensation signal to obtain a three-phase target modulation reference voltage; and determining a three-phase switch drive signal based on the three-phase target modulation reference voltage, wherein the three-phase switch drive signal is used to control the midpoint potential. This method aims to improve the reliability of midpoint potential suppression.

Disclosed are a motor parameter identification method and device, comprising: controlling the motor to operate in a speed closed loop and current closed loop mode according to a reference model of the motor, and obtaining direct-axis voltage, cross-axis voltage, direct-axis current, cross-axis current and motor speed; obtaining direct-axis estimated current and cross-axis estimated current according to an adjustable model of the motor, the direct-axis voltage and the cross-axis voltage; obtaining direct-axis error current according to the direct-axis current and the direct-axis estimated current, and obtaining cross-axis error current according to the cross-axis current and the cross-axis estimated current; adjusting the direct-axis estimated inductance and the cross-axis estimated inductance in the adjustable model through feedback of an adaptive rate model, so that the direct-axis error current and the cross-axis error current converge; the adaptive rate model and the adjustable model adopt a salient pole ratio of the motor. The salient pole ratio of the motor is introduced in the application, the direct-axis inductance parameter and the cross-axis inductance parameter are decoupled and processed, direct coupling of the direct-axis inductance estimated value and the cross-axis inductance estimated value is avoided, and the adaptive rate model is simplified.

The application relates to a permanent magnet synchronous motor multi-source nonlinear disturbance suppression method and system, and belongs to the technical field of permanent magnet synchronous motor control. The application comprises the following steps: establishing an electromechanical coupling discrete model of a permanent magnet synchronous motor actuator; designing a linear extended state observer based on a super-local model to observe system total disturbance in real time; decomposing the system total disturbance into multiple nonlinear disturbance factor components based on the electromechanical coupling discrete model, and calculating the contribution degrees of the components; designing a backstepping adaptive controller based on the contribution degrees, and combining the linear extended state observer to perform feedforward compensation; designing a deadbeat predictive current controller, and performing weighted fusion of the backstepping adaptive controller through a dynamic weight optimization strategy to generate a control voltage; and applying the finally generated d-axis and q-axis voltage control quantities to the permanent magnet synchronous motor actuator. The application can precisely suppress multi-source nonlinear disturbance, and improve the tracking accuracy, dynamic response speed and robustness of the system.

The present application relates to the technical field of conductive ring, and provides a conductive ring, a conductive module, a motor and equipment, the conductive ring includes a support part, the support part has a containing space arranged in the axial direction;The inner wall surface of the containing space is provided with a fixed conductive part and a telescopic conductive part in the circumferential direction, and the fixed conductive part and the telescopic conductive part protrude from the inner wall surface of the containing space.The telescopic conductive part can realize the body conduction with the motor shaft at low speed, and realize the release of shaft voltage through the telescopic conductive part.Further, the telescopic conductive part can work together with the fixed conductive part to realize stable conduction at medium speed.Further, it can be separated from the abutment with the motor shaft body at high speed, which avoids the wear of the telescopic conductive part at high speed and improves the service life of the conductive ring.

The application relates to the field of generator set operation and maintenance, and provides a large shaft grounding device, which comprises a fixing tool, a grounding wire, a constant-voltage loading mechanism and a grounding shoe. The grounding shoe comprises a conductive base layer and a low-contact-resistance layer which are sequentially stacked. The conductive base layer is connected with the grounding wire. The constant-voltage loading mechanism is connected between the fixing tool and the conductive base layer. The side surface of the low-contact-resistance layer opposite to the conductive base layer is an arc surface and is used for abutting against the surface of the large shaft. Based on the above structure, the electrostatic charge of the large shaft can be preferentially led away through the path of the low-contact-resistance layer, the conductive base layer and the grounding wire, the grounding effect of the large shaft grounding device on the large shaft can be effectively improved, the charge leading effect of the large shaft grounding device can be effectively improved, the accumulation of electrostatic charge to form a suspended potential can be effectively and reliably hindered, the shaft voltage can be reduced, the risk of the breakdown discharge phenomenon can be reduced, and the risk of the electric corrosion of the bearing caused by the current passing through the bearing can be reduced.

The present application relates to the technical field of motor control, and particularly relates to a motor driving method and system for suppressing current fluctuation, which comprises the following steps: receiving a frequency instruction, and generating a forced rotation angle and an instruction input voltage corresponding to the frequency instruction according to a preset V / f relationship; collecting two-phase stator phase currents on the output side of an inverter driving system, and performing synchronous rotation coordinate transformation on the two-phase stator phase currents with the forced rotation angle as a transformation angle to obtain a d-axis feedback current; comparing the d-axis feedback current with a preset d-axis current reference value to obtain a current deviation, and inputting the current deviation into a proportional integral regulator to output a d-axis voltage instruction; determining a q-axis voltage instruction according to the instruction input voltage and the d-axis voltage instruction, so that the amplitude of a voltage vector obtained by combining the d-axis voltage instruction and the q-axis voltage instruction is equal to the amplitude of the instruction input voltage; performing synchronous rotation coordinate inverse transformation on the d-axis voltage instruction and the q-axis voltage instruction with the forced rotation angle as a transformation angle to obtain a three-phase voltage instruction; generating a switching driving signal of the inverter driving system according to the three-phase voltage instruction, and using the switching driving signal to control the inverter driving system to output a three-phase driving voltage to an induction motor. The present application aims to solve the problems that the existing open-loop V / f control of the induction motor is prone to current fluctuation, torque pulsation and decline in running stability, and the existing suppression scheme is greatly dependent on motor parameters, has a complex algorithm and a high implementation cost.

The application provides a LMS-SOGI three-phase phase-locked loop design method and system suitable for a non-ideal power grid, and the method comprises the following steps: sampling three-phase grid-connected voltages of a grid-connected inverter to obtain voltage components through Clark transformation; the voltage components are respectively sent into two SOGI structures to extract positive sequence components of the grid-connected voltages; a least mean square LMS filter link mathematical model is constructed to design a least mean square LMS filter link step parameter; then, the positive sequence components of the grid-connected voltages are subjected to LMS filtering to obtain d-axis and q-axis positive sequence components of a fundamental frequency grid-connected voltage, the q-axis component of the fundamental frequency grid-connected voltage is subtracted by 0 to obtain a q-axis voltage phase-locked error signal, an output signal angular frequency adjustment amount ω is obtained through a PI controller, and a phase θ is obtained through integration. Finally, a three-phase grid voltage LMS-SOGI phase-locked model is built in MATLAB / Simulink simulation software, and different grid voltages are selected for comparative analysis of the filtering effect. The application solves the technical problem that the phase-locked technology of the grid-connected inverter is difficult to accurately lock the voltage frequency and phase in a specific scene.

The application discloses a single-phase control system and method based on d-q rotating coordinate transformation, adopts a double-loop architecture of a voltage outer loop and a current inner loop, the voltage outer loop filters a sampling voltage through a second-order generalized integrator, obtains d-q axis voltage components through Park transformation, and generates a d-axis current reference value by using a PI regulator; the current inner loop also filters and transforms the sampling current, inputs a current error into a PI regulator to obtain a current compensation component, eliminates the coupling influence between d-q axes through decoupling operation, and finally generates a duty cycle signal for driving an inverter through inverse coordinate transformation. Through the double-loop cooperative control and decoupling algorithm, the application realizes high-precision voltage stabilization of the inverter output voltage and fast dynamic response of the current, effectively suppresses harmonics and load disturbance, and improves the output power quality.

The application discloses a high-speed permanent magnet synchronous motor Delta-Sigma modulation and parallel implementation method, and belongs to the field of power electronics. The method applies the Delta-Sigma modulation technology to high-speed permanent magnet synchronous motor control and is realized through a field programmable gate array. The system adopts a cooperative architecture of a controller and the FPGA: the controller is responsible for double closed-loop control and non-inductive algorithm, and outputs d-q axis voltage; in order to adapt to FPGA fixed-point operation, the voltage is first converted to a 60° g-h coordinate system to strip off irrational number operation. The FPGA utilizes a parallel pipeline structure to synchronously judge reference voltage vector sector n and deviation vector area m. Finally, a switch vector output is selected according to the setting rules of n and m. The method optimizes voltage spectrum, suppresses current high-frequency harmonics and significantly improves the real-time performance and engineering realizability of the modulation link without increasing the burden of the controller.

The application discloses an online identification method and system for parameters of a permanent magnet synchronous motor, and relates to the technical field of data processing. The method comprises the following steps: loading real-time operation data of the motor; performing coordinate transformation and inverter nonlinear compensation on the real-time operation data to obtain d-q axis voltage observation values and d-q axis current observation values; inputting the d-q axis voltage observation values, the d-q axis current observation values and the rotation speed of a plurality of continuous control cycles into a time sequence input tensor, and inputting the time sequence input tensor into a lightweight gated recurrent physical unit network to obtain a parameter set to be identified at the current time; correcting the parameter set to be identified according to a motor voltage equation residual error at the current time through an online recursive formula to obtain final identification parameter values; and outputting the final identification parameter values to a motor controller for current loop decoupling or model predictive control. The application effectively improves the real-time performance of online identification of parameters of the permanent magnet synchronous motor and the dynamic tracking capability of the parameter time variation.

This invention discloses a traction control method, device, equipment, and storage medium for a permanent magnet synchronous motor, belonging to the field of traction control. It determines the q-axis voltage control law based on a direct speed loop model and the d-axis voltage control law based on a hyperlocal model of the d-axis current. The d-axis voltage control quantity is determined based on the detected d-axis current value, the reference d-axis current value, and the preset d-axis voltage control law. Simultaneously, the q-axis voltage control quantity is determined based on the detected speed value, the reference speed value, and the preset q-axis voltage control law. Finally, traction control of the permanent magnet synchronous motor is achieved based on the d-axis and q-axis voltage control quantities. This eliminates the control delay inherent in the series-connected outer speed loop and inner q-axis current loop. Furthermore, the application of the hyperlocal model significantly reduces the dependence on motor parameters, thereby meeting the high-precision, fast-response, and stable speed control requirements of the traction system.

The present application relates to the technical field of permanent magnet synchronous motor control, and particularly relates to an adaptive method for actively feeding forward and compensating cogging torque of super-multipole permanent magnet synchronous motor, which is as follows: a cogging torque feedforward compensation model is established, and the amplitude-phase nonlinear parameters are converted into linear weight coefficient form through triangular orthogonal decomposition; secondly, the AC component of the q-axis voltage output by the current PI regulator is extracted as a compensation residual error signal, the weight coefficient is updated on-line and iteratively using the normalized least mean square algorithm, and adaptive tracking of the cogging torque change caused by temperature drift and mechanical wear is realized; finally, combined with a dual-redundant position feedback system, a double-channel independent weight coefficient maintenance, cross-checking and seamless fault switching mechanism is established. The present application can reduce torque ripple under low-speed working conditions, improve the low-speed stability and control accuracy of super-multipole permanent magnet synchronous motor, and meet the functional safety requirements of aviation-grade electric drive systems.

The application belongs to the technical field of motor control, and relates to a kind of air conditioner compressor rotating speed fast observation method and system, the method comprises: three-phase current of motor is transformed into dq axis current actual value;PI is carried out PI adjustment to the difference between motor rotating speed given value and motor rotating speed actual value, and q axis current given value is obtained, and the difference between q axis current given value and q axis current actual value is carried out PI adjustment to obtain q axis voltage given value;The difference between d axis current given value and d axis current actual value is carried out PI adjustment to obtain d axis voltage given value;Dq axis voltage given value is transformed into alpha axis voltage given value;Based on alpha axis voltage given value and the output voltage of frequency as motor rotating speed observation value, the updated motor rotating speed observation value is obtained.The application can realize stable observation of motor rotating speed in full speed range, and the observation result is accurate, especially when motor rotating speed dynamically changes, excellent dynamic tracking effect can be realized.

This application relates to the field of motor control technology, and in particular to a method, system, device, and medium for switching motor operating modes. The method includes: after system initialization, controlling the motor to enter a first operating mode; detecting the duty cycle of the inverter module, and controlling the motor to switch to a second operating mode when the switching conditions are met; while the motor is in the second operating mode, detecting the direct-axis voltage, quadrature-axis voltage, and bus voltage and executing a field-weakening control algorithm, and controlling the motor to switch back to the first operating mode when the reverse switching conditions are met. By adopting this application, dynamic adaptive switching between two motor operating modes can be achieved, adapting to different operating conditions of low-to-medium speed conventional operation and high-speed high-performance operation, taking into account the stability of the system during startup and conventional operation, as well as the output capacity and efficiency during high-speed operation, achieving performance optimization management across the entire operating range, and improving system robustness and overall operating performance.

This application provides a method and apparatus for suppressing current harmonics in an electrolytic capacitor-free drive system, relating to the field of permanent magnet synchronous motor drive control, and used to improve grid-side current quality. The method includes: acquiring a sawtooth wave of the same frequency, which is generated based on the LC resonant frequency; comparing the sawtooth wave with a given value to obtain a rectangular wave, and amplifying the rectangular wave to obtain a given damping pulse; shifting the phase of the given damping pulse according to the three-phase grid-side current to obtain an applied damping pulse; obtaining an α-axis voltage compensation component and a β-axis voltage compensation component based on the applied damping pulse; superimposing the α-axis voltage compensation component onto the α-axis voltage to obtain an α-axis voltage command; superimposing the β-axis voltage compensation component onto the β-axis voltage to obtain a β-axis voltage command; and applying the α-axis voltage command and the β-axis voltage command to a space vector pulse width modulation (SVPWM) inverter.

An electrical machine with at least one electrical resistor (24) for deriving shaft voltages occurring on the rotor shaft (2) of a rotor (1), characterized in that the electrical resistor (24) is located in a contact ring (13) mounted on the rotor shaft (2) between contact surfaces (17, 23, 25, 28, 29) attached to the contact ring (13), and that the resistor (24) is electrically connected via the contact surfaces (17, 23, 25, 28, 29) on the one hand to the rotor shaft (2) and on the other hand to the excitation winding (14) of the rotor (1).

This invention relates to the field of automatic control technology, and more specifically, to a constant-speed output control method for a magnetic drilling motor based on dynamic current feedback. The magnetic drilling motor is an embedded permanent magnet synchronous motor driven by a three-phase inverter. The method includes the following steps: Step 1: Simultaneously setting a tunnel reluctance current sensor and a PCB-embedded Rogowski coil on each power bridge arm of the three-phase inverter; Step 2: Constructing a fractional-order extended state observer based on the reconstructed quadrature-axis voltage value reconstructed according to the DC bus voltage and the space vector pulse width modulation duty cycle, and outputting a speed feedback signal and an equivalent disturbance voltage compensation signal; Step 3: The speed control loop generates a quadrature-axis current reference value based on the difference between the speed setpoint and the speed feedback signal, thereby achieving constant-speed output control of the magnetic drilling motor. This invention reduces unnecessary heat generation and energy loss, and extends the continuous operation time of the equipment.

The application discloses a kind of fast automatic calibration method, system and controller based on automated test stand. By test stand, a fixed rotating speed is given under given base speed, direct-axis current and quadrature-axis current instruction is input according to set step, controller end collects direct-axis voltage, quadrature-axis voltage and motor temperature and the like signal, and the collected data and current point data are sent to test stand end by CAN. Test stand end collects the torque of the motor to be measured, and the data sent back by controller are stored in database. The calibration data of test stand database are extracted for data processing, and the global current table is obtained by voltage-torque compensation method and composite flux method, so as to reduce the influence caused by flux linkage change. The method, system and controller only need to determine the data under one rotating speed, and the calibration process is automated, so the calibration efficiency of permanent magnet synchronous motor is greatly improved.

This invention discloses a positive-sequence and negative-sequence phase-locked loop (PLL) control method, medium, and system under asymmetric faults. The method includes the following steps: acquiring the three-phase AC voltage signal at the grid connection point of the renewable energy grid-connected system, extracting the positive-sequence q-axis voltage and the negative-sequence q-axis voltage at the generator terminal; then inputting them into the positive-sequence PLL and negative-sequence PLL respectively to construct the positive-sequence and negative-sequence PLL control structure; calculating the intermediate variable matrix based on the sequence domain circuit according to the asymmetric fault type; during the asymmetric fault, introducing the intermediate variable matrix into the positive-sequence and negative-sequence PLL control structure to form an improved positive-sequence PLL control model and an improved negative-sequence PLL control model, so as to adaptively adjust the output angular frequency of the PLL. This invention can effectively reduce the risk of transient synchronization instability in renewable energy systems during faults, ensure that renewable energy grid-connected systems can maintain synchronous operation with the grid when asymmetric faults occur, and significantly improve the transient synchronization stability of the system.

This application provides a motor control method and a motor control circuit. The motor control method includes: acquiring the d-axis voltage and q-axis voltage of the motor in a two-phase rotating coordinate system; if the motor rotor is in a low modulation region and the q-axis voltage is within a set prohibited range of the q-axis region, optimizing the q-axis voltage to generate an optimized q-axis voltage, the optimized q-axis voltage being equal to the boundary value of the prohibited range of the q-axis region with the same positive and negative sign as the q-axis voltage, the boundary value including an upper boundary value and a lower boundary value; and generating a PWM pulse signal for controlling the motor based on the d-axis voltage and the optimized q-axis voltage. By increasing the absolute value of the q-axis voltage, which is relatively small when the motor rotor is in the low modulation region, the width of the generated PWM pulse signal can be increased, thereby satisfying the minimum time window for current sampling, avoiding motor start-up failure or abnormal stop, and improving the stability of motor operation.

The application discloses a kind of detection methods, systems, equipment and storage medium of short-time surge impact voltage resistance of insulating bearing, wherein the method comprises: at least one bearing voltage data of the measured bearing is obtained by the measuring device;Simulate short-time surge impact voltage data in the shaft voltage data, and the test device is tested to each measured bearing in the at least one measured bearing, and the voltage waveform corresponding to each measured bearing is obtained;The safety impact voltage corresponding to each measured bearing is determined based on the voltage waveform and the thickness parameter of the insulating layer corresponding to each measured bearing;According to the thickness parameter and the safety impact voltage, first curve relationship is determined;The first curve relationship is used to design the thickness of the insulating layer corresponding to different bearings in the motor.

This invention discloses a generator shaft current harmonic filtering and shaft voltage precise suppression device, belonging to the technical field of generator protection devices. During generator operation, the device, through the cooperation of a detection module, filtering module, active compensation module, control module, and discharge component, precisely offsets shaft voltage fluctuations on the shaft. Simultaneously, the grounding brush on the discharge component provides a low-resistance grounding path for the shaft, discharging residual shaft voltage and harmonic current, stabilizing the shaft potential within a safe range. Furthermore, during grounding brush operation, the cooperation of a pressure component, elastic component, drive component, and linkage component maintains a relatively stable compressive force on the grounding brush during wear, ensuring good contact between the grounding brush and the shaft, further guaranteeing the normal discharge of shaft voltage, shaft current, and high-frequency harmonic current to the ground.

The application discloses a three-stage synchronous motor based on a third-order phase-locked loop and a simplified demodulation method of a rotor position at zero and low speed, and single-phase AC excitation is applied to a main excitation machine of the three-stage synchronous motor to make dq-axis voltage with position error information generated on a stator side of a main generator; a process processing signal with a low-frequency position error signal is constructed through band-pass filtering and product operation; a middle signal is obtained by adopting a wave trap to suppress a second harmonic component of the process processing signal; the middle signal is input into a third-order phase-locked loop to calculate an estimated position of a rotor, sector correction is carried out according to a stator current sign, an initial position angle is obtained, and high-precision rotor position estimation under a zero and low speed working condition of the three-stage synchronous motor is realized. In the demodulation process of the application, the harmonic analysis frequency is clear, the structure of the wave trap cascaded with the third-order phase-locked loop is adopted, low-frequency position error signals and high-frequency harmonics are effectively isolated, and the rotor position estimation precision in the acceleration process of the motor is significantly improved.