70 results about "Position error signal" patented technology

The invention discloses a permanent magnet synchronous motor sensorless control method based on a dynamic position error. A transition stage is provided, per-unit estimation position errors between a first position error signal obtained based on a high-frequency signal injection method and a second position error signal obtained based on a sliding mode observer are compared, an optimal switching speed point is dynamically determined, smooth fusion is carried out on the two position errors by using a nonlinear weighting function, and the optimal switching speed point is obtained. And finally, the estimated position and rotating speed are obtained through a phase-locked loop. And finally, position tracking is carried out by adopting different error signals according to the estimated rotating speed. According to the method, the problem of estimation value pulsation and jump caused by the fact that a traditional method depends on fixed experience switching points is solved, smooth and self-adaptive switching of the two estimation methods in the full-speed domain range is achieved, the control precision and operation stability of the system are remarkably improved, the structure is simple, and engineering implementation is easy.

The invention provides a control method and device of an optical anti-vibration motor, and relates to the technical field of optical anti-vibration. The method comprises the following steps: acquiring a position error signal of a motor, wherein the position error signal is a signal determined according to a difference relationship between a current position and an expected position of the motor; performing feature extraction according to the position error signal to obtain an amplitude feature value representing the oscillation degree of the system; the current state of the system is determined according to the amplitude characteristic value, an error absolute value and the matching relation between the state of the system at the previous moment and a preset skipping condition, the error absolute value is the absolute value of the position error signal, and the preset skipping condition is the condition needing to be met by the amplitude characteristic value and the error absolute value when the system state is switched; and determining an adjustment coefficient according to the current state of the system and the amplitude characteristic value, thereby determining the current gain control output of the system by using the adjustment coefficient. According to the scheme, the self-oscillation of the optical anti-vibration system can be suppressed accurately and effectively.

The invention relates to a sensorless high-performance control method for an oil pump motor in a low-speed domain. The sensorless high-performance control method comprises the following steps: step 1, building a high-frequency signal injection model; based on a traditional permanent magnet synchronous motor model, a high-frequency mathematical model of the oil pump under a d-q axis system is derived, and the relation between q-axis high-frequency response current and the angle error is obtained; step 2, random amplitude and frequency signal injection; obtaining q-axis high-frequency response current based on a high-frequency response current equation and the injected voltage signal with random amplitude and frequency; 3, performing signal demodulation based on an adaptive filtering algorithm to obtain an angle error signal; and step 4, after the rotor position error signal is extracted in the step 3, realizing rotor position observation through a PI observer. The noise caused by fixed frequency injection can be greatly reduced in the low-speed domain state of the oil pump motor; and secondly, a target signal can be accurately extracted to participate in closed-loop control or rotor position observation, so that the control performance is improved.

The invention discloses a permanent magnet synchronous motor position and speed estimation method of a phase-locked loop based on a complementary sliding mode observer and an augmented sliding mode, and the method comprises the following steps: 1, sampling the three-phase current of a permanent magnet synchronous motor, and obtaining the current under a two-phase static coordinate system through coordinate transformation; 2, an estimated current value is calculated according to the estimated current value mathematical model of the permanent magnet synchronous motor, a current error is obtained through calculation, and the current error serves as input of a follow-up observer; 3, calculating a feedback law according to the complementary sliding mode observer mathematical model, and calculating to obtain a back electromotive force; and step 4, performing integral calculation on the position error signal by utilizing the designed improved phase-locked loop based on augmented sliding mode control based on the back electromotive force to obtain the rotating speed of the motor and the position of the rotor. The dynamic performance of the sensorless control system of the permanent magnet synchronous motor can be effectively improved.

The invention discloses a position-sensorless heavy-load starting method for a permanent magnet synchronous motor. The method comprises the following steps: establishing a discrete current model of the permanent magnet synchronous motor in a two-phase static coordinate system under the excitation of a high-frequency square wave signal; injecting the six-pulse voltage into the permanent magnet synchronous motor based on a three-phase static coordinate system to carry out rotor magnetic pole identification so as to correct the initial electrical angle of the rotor, and further obtaining a rotor position error signal in combination with a discrete current model; a rotor position error signal is processed through an improved phase-locked loop control system based on model reference self-adaption, and then the finally estimated rotating speed and electrical angle of the rotor are obtained; and then inputting the signal as a feedback signal into a magnetic field orientation control system to realize position-sensorless closed-loop starting control of the permanent magnet synchronous motor under a heavy load condition. By means of the method, the reliability of the starting process and the stability of a control system can be remarkably improved, and therefore reliable position-free closed-loop control under the low-speed large-load working condition and even within the full-speed domain range is achieved.

The application discloses a kind of permanent magnet synchronous motor position sensorless control demodulation methods based on three-branch external tangent demodulation, belong to permanent magnet synchronous motor control field.This method injects random half-cycle square wave high-frequency voltage signal in the estimation synchronous rotating coordinate system, collects three-phase current and extracts high-frequency current component under stationary αβ coordinate system;According to the estimated electrical angle, construct three sets of three-branch external combined current variables, obtain the demodulation quantity corresponding to the position error sine and cosine components by algebraic combination, then obtain the position error signal by external tangent relationship, and estimate rotor position and speed by phase-locked loop.This method does not depend on the strict synchronization multiplication of random square wave demodulation carrier and sampled current, can weaken or avoid the equivalent delay influence of about 1.5Ts caused by digital sampling, improve the position estimation accuracy and robustness under random half-cycle switching condition.

The invention discloses a position and speed nonlinear estimation method and device based on disturbance observation of a wind generating set. The method comprises the following steps: 1, measuring rotor position information of a motor through an encoder; step 2, subtracting the rotor position information obtained in the step 1 from a rotor position estimation value to obtain a rotor position error signal; the rotor position estimation value is the rotor position information estimated by the nonlinear extended state observer in the step 4; 3, designing a proper nonlinear function for the nonlinear expansion state observer; and 4, constructing a third-order nonlinear extended state observer based on the error signal in the step 2 and the nonlinear function in the step 3, and estimating the position and the speed of the fan. Compensation of internal and external disturbances of the system is realized, and the position and speed of the wind driven generator are estimated.

Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: obtain a first value of a first servo burst signal and a second value of a second servo burst signal associated with a servo pattern in a track of the disk; calculate an adjusted first value and an adjusted second value by adjusting one or both of the first value and the second value based on a measure of servo pattern distortion associated with the track; generate a position error signal (PES) using the adjusted first value and the adjusted second value; and control a position of the head over the track using the PES.

According to one embodiment, multiple first positions are set in a radial direction of a magnetic disk. The multiple first positions include multiple second positions and a third position different from the multiple second positions. A controller of a magnetic disk apparatus executes a first process in which an RRO correction value is measured at each of the multiple second positions and measurement of an RRO correction value at the third position is skipped. After the first process, the controller executes a second process of performing write or read access to multiple tracks. The second process includes acquiring a position error signal by a read head during the write or read access, and calculating an RRO correction value for the third position based on the position error signal.

Various illustrative appearances relate to a data storage device, a method, and one or more processing devices configured to: open a servo gate in the selected head during a read operation to read the first servo bursts, the sync mark, and the second servo bursts in one of the servo sectors; and determine a position error signal for the selected head based on reading the first servo bursts and the second servo bursts.

The invention discloses an online monitoring system and method for the vibration of a power transformer winding, and the invention relates to the field of transformer winding vibration monitoring. The system comprises a parameter setting module, an error signal detection module, an error signal verification module and a signal data latching module; the parameter setting module sets a plurality of vibration sensors on a transformer and a reference plane, obtains vibration signals, establishes a two-dimensional plane model, and obtains the positions of the vibration sensors on the transformer; the error signal detection module analyzes the state of the transformer winding according to the difference of the vibration signals set on the transformer and the reference plane; the error signal verification module compares the difference of the vibration signal with the vibration signal in the historical data, and analyzes whether the vibration signal will cause the winding to generate an early warning situation; the signal data latching module moves the vibration sensor set on the transformer, obtains the characteristics of the vibration signal when the vibration sensor moves to the optimal position, and encrypts and saves the characteristics of the vibration signal.

A voice coil motor assembly (VCMA), such as for a hard disk drive, includes a low-density voice coil and a high-density coil stiffener disposed inside the coil of wire. The low-density voice coil, utilizing copper-clad aluminum or aluminum wire, is configured to increase the second coil torsion mode frequency of the VCMA, thereby bringing it closer to the second torsion mode frequency of the actuator arms. In conjunction, the high-density stiffener, utilizing steel or copper or zinc, is configured to increase the mass of the VCMA to compensate for the lower-density wire in regard to the center of mass of the VCMA about its axis of rotation. In viewing under customer box vibration conditions and in terms of position error signals (PES), a non-trivial peak in the PES spectrum due to the second coil torsion mode is largely eliminated, and the power of PES is reduced to about half.

Controlling a shingled magnetic recording (SMR) hard drive involves writing, to a first track of a zone pre-sized based on a nominal track width based on an expected mean track width across an entire zone, a portion of a write operation according to the nominal track width. Then, based on the positional accuracy of the first track writing, determining a second track position for an adjacent second track, and writing the second track another portion of the write operation according to the determined second track position. Thus, the determination and position of a given track is determined by the positional accuracy of a previously written track, considering for example the position error signal corresponding to the writing of the previously written track. Thus, the track pitch is effectively defined by the average positional error across a zone rather than by a worst-case scenario positional error across the zone.

The present invention belongs to the field of electric motor control technology, and particularly relates to a real-time method for estimating the rotor position of a permanent magnet synchronous motor. The method extracts the effective flux phase information of the motor and performs differential processing on the effective flux phases of two adjacent samples to obtain a feedforward estimated speed component. A position error signal is constructed and sent to a phase-locked loop for proportional-integral closed-loop regulation. After low-pass filtering, a closed-loop estimated speed component is obtained. The two speed components are added and low-pass filtered to obtain an estimated speed #imgabs0#. This is then integrated to obtain the estimated rotor position #imgabs2# of the permanent magnet motor. This method optimizes speed estimation and is highly portable. It is applicable to various implementations of back-electromotive force models in position sensorless control methods for permanent magnet synchronous motors, significantly improving the dynamic response of traditional position sensorless control methods. The present invention also provides a non-transitory readable recording medium storing a program for the method and a system containing the medium. The program can be called through a processing circuit to execute the method.

Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: during a read operation, open a servo gate in the selected head in order to read the first servo bursts, the sync mark, and the second servo bursts in one of the servo sectors; and determine a position error signal for the selected head based on reading the first servo bursts and the second servo bursts.

The invention discloses a five-phase hybrid excitation motor rotor position detection method based on excitation winding high-frequency pulsating injection, and the method comprises the steps: injecting a high-frequency pulsating voltage signal to an excitation winding, extracting a current signal containing rotor position information in a q axis of a third harmonic space, and inputting the current signal to a cascade phase-locked loop; the high-frequency carrier frequency is locked through the first-stage phase-locked loop, noise is filtered out, a pure high-frequency component is extracted, the high-frequency component is demodulated through the second-stage phase-locked loop, position error signals are extracted through low-pass filtering, proportional-integral control is combined, the rotor position and rotating speed information of the five-phase hybrid excitation motor is obtained, and operation without a position sensor is achieved. According to the excitation winding injection method provided by the invention, the influence of the salient pole effect of the rotor is fully considered, the characteristic of uniform distribution of an excitation magnetic field is utilized, and the position of the rotor can be accurately detected under the condition that the salient pole ratio of the rotor is low; moreover, the method is high in position detection precision, is high in anti-interference capability, is simple and convenient, and is easy to achieve.

The present application discloses a motor control device, including: a forward path including a position reference unit for generating a motor rotation position reference signal, a position control unit for controlling the motor rotation position, a speed control unit for controlling the motor speed, and a current control unit for controlling the motor current, which are connected in sequence; and a feedback path including a first feedback unit for feedbacking the current rotation position and current rotation speed of the motor, a second feedback unit for feedbacking the current motor current, and a feedforward unit for selectively compensating the motor current. The feedforward unit outputs a selectively compensating current signal according to the position error signal from the position control unit. The current control unit outputs a control signal for controlling the motor according to the selectively compensating current signal, a first current reference signal from the speed control unit, and a current feedback signal from the second feedback unit. The present application is beneficial to improving the stability and anti-interference ability of reaching the position.

The invention relates to a data storage device with auxiliary pulse trains in servo sectors. Various illustrative aspects relate to a data storage device, a method, and one or more processing devices configured to open a servo gate in a selected head during a read operation, the first servo pulse train, the synchronization mark and the second servo pulse train in one of the servo sectors are read; and determining a position error signal of the selected head based on reading the first servo pulse train and the second servo pulse train.

This invention provides a data storage device that controls the torsional mode of a coil and reduces the power consumption of an actuator. [Solution] A voice coil motor assembly (VCMA) 400 for hard disk drives and the like includes a low-density voice coil 407 and a high-density coil reinforcement 408 positioned inside the wire coil. The low-density voice coil, utilizing copper-clad aluminum or aluminum wire, increases the second coil torsion mode frequency of the VCMA, thereby bringing it closer to the second torsion mode frequency of the actuator arm 402. In addition, the high-density reinforcement, utilizing steel, copper, or zinc, increases the mass of the VCMA with respect to the center of mass of the VCMA around the rotation axis of the VCMA, compensating for the lower-density wire. With respect to the position error signal (PES) under customer box vibration conditions, significant peaks in the PES spectrum are largely eliminated, and the power of the PES is reduced by approximately half.

This invention discloses a sensorless permanent magnet synchronous motor (PMSM) control method based on an adaptive phase-locked loop (PLL) and an anti-saturation controller, comprising the following steps: S1, injecting a high-frequency square wave voltage signal into the estimated synchronous rotating coordinate system; acquiring the stator current of the PMSM to obtain a high-frequency current deviation signal in a two-phase stationary coordinate system; S2, using an improved anti-integral saturation controller as the speed loop controller to receive the speed command and feedback speed error signal; simultaneously, calculating the rotor position error signal based on the high-frequency current signal; S3, inputting the rotor position error signal to the adaptive PLL, which adaptively adjusts its undamped oscillation frequency according to the motor's operating state to achieve dynamic adjustment of the observation bandwidth, and outputs rotor position and speed estimates; sensorless vector control of the PMSM is achieved through the estimates. This invention exhibits excellent stability and adaptability during low-speed motor operation.

The invention relates to the technical field of motion control, and discloses a positioning method for a high-precision servo linear motor, and the method comprises the steps: carrying out the signal mapping of a positioning instruction inputted into the servo linear motor, and obtaining a control signal; performing driving control on the servo linear motor based on the control signal to obtain a preliminary motion state; detecting the initial motion state in real time to obtain a position feedback signal; performing error identification on the target position information and the position feedback signal to obtain an initial position error signal; performing fusion compensation on the initial position error signal and the multi-source sensing data to obtain a high-precision position error signal; the motion parameters of the servo linear motor are subjected to real-time compensation control based on the high-precision position error signal, a high-precision positioning result is obtained, and the positioning precision and efficiency of the servo linear motor can be improved.

The invention discloses a permanent magnet synchronous motor high-frequency square wave injection method based on parameter autonomous optimization, and the method comprises the steps: building a mathematical model of a permanent magnet synchronous motor under high-frequency excitation, and injecting a high-frequency square wave voltage signal into an estimated axis of a two-phase rotating coordinate system; the high-frequency current response signal is processed under the measurement shafting, and a rotor position error signal is decoupled; processing the rotor position error signal by using a phase-locked loop to obtain the rotating speed and rotor position information of the motor; and carrying out autonomous optimization setting on PI controller parameters of the phase-locked loop by adopting a dogvessel squirt algorithm of a mixed double-leader and vanquish elimination mechanism. The problems that a high-frequency voltage signal injection method is low in detection precision and is greatly influenced by non-ideal factors, and phase-locked loop parameters are difficult to set are solved, and the rotor position observation precision and robustness of the permanent magnet synchronous motor without sensor control under the zero-low-speed working condition are improved.

Example control circuitry, data storage devices, and methods for parallel self-servo write in a data storage device are described. The data storage device may include multiple heads actuated over different surfaces of a data storage device and receive read signals from two different heads over two different surfaces in parallel. Position error signals may be determined from each read signal and corresponding position compensation values may be determined for their respective microactuators. Application of these compensation values may maintain their relative positions for parallel writing of servo tracks based on their respective spiral reference patterns and TPI settings.

The present disclosure describes example circuits, data storage devices, and methods to provide parallel self-servo writes in a data storage device. The data storage device may include a plurality of heads actuated over respective surfaces of a storage medium, and at least two preamplifiers and a read path to a channel circuit. The control circuit can select the magnetic heads connected through different preamplifiers to perform parallel self-servo writing and receive read signals from the selected magnetic heads in parallel. The read signals, which may be based on a self-servo write reference spiral previously written to the storage medium, may be used to determine respective position error signals for the two heads and to control their respective positions with respective control signals to respective micro and / or milliactuators on shared voice control motors and arms supporting the heads.

Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: obtain a first value of a first servo burst signal and a second value of a second servo burst signal associated with a servo pattern in a track of the disk; calculate an adjusted first value and an adjusted second value by adjusting one or both of the first value and the second value based on a measure of servo pattern distortion associated with the track; generate a position error signal (PES) using the adjusted first value and the adjusted second value; and control a position of the head over the track using the PES.

The present disclosure describes example circuits, data storage devices, and methods for parallel self-servo writes in a data storage device. The data storage device may include a plurality of heads that actuate over different surfaces of the data storage device and receive read signals in parallel from two different heads over two different surfaces. A position error signal may be determined from each read signal, and a corresponding position compensation value may be determined for a respective microactuator of the position error signal. Applications of these compensation values may maintain their relative position based on their respective helical reference patterns and TPI settings for parallel writing of servo tracks.

The present application provides an active noise reduction method, including: determining a target noise reduction area error signal corresponding to the monitoring position error signal based on the monitoring position error signal collected by a monitoring microphone disposed at a monitoring position corresponding to a target noise reduction area, where the target noise reduction area is an area that needs to be noise-reduced; determining a noise reduction parameter based on the target noise reduction area error signal; generating a noise reduction signal based on the noise reduction parameter to perform noise reduction on the target noise reduction area. Based on the monitoring position error signal, a target noise reduction area error signal that can fully represent the remaining noise signal after noise reduction in the target noise reduction area is obtained. The noise reduction parameter for the target noise reduction area is determined based on the target noise reduction area error signal, and a noise reduction signal is generated based on the noise reduction parameter for the target noise reduction area to perform noise reduction on the target noise reduction area, so as to minimize the noise in the target noise reduction area.

Example control circuitry, data storage devices, and methods to use dual servo channels for burst gain switching are described. The data storage device may include two servo channels, such as the dual channels in a two-dimensional magnetic recording channel, that receive read signals for the same servo sector in parallel. One channel is calibrated to use a gain value for a first portion of the servo pattern, such as the preamble and Gray code for the servo address mark, and the other channel is calibrated to use a different gain value for a second portion of the servo pattern, such as the burst pattern. The resulting signal values may then be combined to determine the position error signal. Both channels may be configured to use different gain values for different portions of the read signal with corresponding gain switching and combining them may use the most reliable portions of each signal.

A controller calculates, based on a positional error signal, an evaluation amount of damage on data of an adjacent track caused by a write operation, and compares a first amount being the evaluation amount with a first threshold value corresponding to a correction limit of an error correction in units of tracks. The controller interrupts the write operation in response to determining that the first amount is greater than the first threshold value. The controller executes a read operation on the adjacent track, acquires a metric representing a signal quality of the data of the adjacent track read by the read operation, calculates the evaluation amount based on the metric, and compares a second amount being the evaluation amount with the first threshold value. The controller continues the write operation in response to determining that the second amount is smaller than a first threshold value.

Example circuits, data storage devices, and methods to provide parallel self-servo write in a data storage device are described. The data storage device may include multiple heads actuated over respective surfaces of storage media and at least two preamplifiers and read paths to a channel circuit. Control circuitry may select heads connected through different preamplifiers for parallel self-servo write and receive read signals from the selected heads in parallel. These read signals, which may be based on self-servo write reference spirals previously written to the storage media, may be used to determine respective position error signals for the two heads and control their respective positions with corresponding control signals to a shared voice control motor and respective micro and / or milli actuators on the arms supporting the heads.