46results about How to "Reduce dynamic error" patented technology

The invention provides a method for controlling a servo system of an active disturbance rejection control technology, and aims to provide a method which has a simple algorithm, wide parameter adaptability and small servo system tracking dynamic error, and keeps the disturbance rejection capability of an automatic disturbance rejection controller (ADRC) control system. The method is realized through the following technical scheme that: firstly, a command differentiator ComD is substituted for a tracking differentiator TD which is arranged for a transition process of a standard active disturbance rejection control algorithm, and extracts a new location command value w1, a new speed command value w2 and a new acceleration command value w3; an extended state observer ESO in the standard active disturbance rejection control algorithm is continuously adopted, and calculates a system location observation value z1, a speed observation value z2 and an acceleration observation value z3; and w1 and z1 form a location error e1, w2 and z2 form a speed error e2, e1 and e2 are sent to a nonlinear state error feedback regulator (NLSEF), w3 and the output u0 of the NLSEF are added, w3 is taken as a feedback value, so the servo system of the improved active disturbance rejection control technology is formed.

The invention relates to a method for follow-up testing of temperature of a steel billet in a furnace, which comprises the steps of primary preparation and the steps of follow-up testing in the furnace. The primary preparation comprises the following concrete steps: (1) drilling a hole on the steel billet to be tested; (2) inserting the hot end part of a thermocouple into the hole drilled in the step (1), and enabling the hot end of the thermocouple to be in contact with the bottom of the hole; filling and compressing the residual space in the hole by the iron powder of which the material is the same as the material of the steel billet to be tested; and (3) connecting the measuring end of the thermocouple to a temperature recorder, enabling the temperature recorder and the steel billet to together enter the furnace, and then, carrying out the steps of follow-up testing in the furnace. The method of the invention can improve the accuracy and the reliability of temperature testing of the steel billet.

The embodiment of the invention relates to a power-supply apparatus and control method, a power amplifying device. The device includes a includes linear branch and a first switch power supply group, the first switch power supply group includes a first current detector and at least two switch power supply branches, the switch power supply branch includes a hysteresis controller and a switch power supply drive and power circuit, the input end of the first electrical current detector is connected with the output end of the linear power supply branch, the input end of the hysteresis controller is connected with the output end of the first electrical current detector, the input end of the switch power supply drive and power circuit is connected with the output end of the hysteresis controller, the output end thereof is in parallel connection with the output end of the linear power supply branch. The embodiment of the invention can improve the band width and the tracking accuracy of the switch power supply, further improve the integral efficiency of the ET power amplifier.

The invention discloses an alternating current synchronous motor controller based on FPGA and a control method thereof. The feedback digital processing of a coder and a current sensor and the controlof the current operation of a motor are simultaneously carried out by FPGA; simultaneously, dynamic errors caused by the system error of the feedback current value and a common mode rejection ratio are reduced in the digital filtering of the current feedback sensor; in the feedback process, a polar duty ratio after digital filtering replaces the feedback current value for converting linear data, thereby avoiding the nonlinear processing in the converting process of the current value and the data errors due to multiplication computation; in the processes of the data logic computation and the processing of a current ring and a speed ring, the absolute value and the symbol bit of the data are used as a data combination, thereby simplifying the data processing of programming design; and in addition, a uniform synchronous clock is supplied in the control and renovating process of the speed ring and the current ring, thereby eliminating the errors caused by a time sequence problem in the data transmission process in the computation and the control of the current ring and the speed ring.

The invention discloses a solar photovoltaic maximum power tracking control method. The solar photovoltaic maximum power tracking control method comprises the following steps that step 1, maximum power tracking is carried out by adopting a variable step perturbation observation method; step 2, after entering a parabola fitting region R, a maximum power point is tracked and determined according toa parabola approximation method; step 3, according to the change of the external environment, the step length is adjusted in real time, the size of the step length is changed dynamically, and maximumpower tracking control is carried out. The solar photovoltaic maximum power tracking control method has the advantages that the position of a working point of a solar photovoltaic system is judged byadopting the perturbation observation method; firstly, it is judged whether or not fitting voltage enters the fitting region R and satisfies fitting conditions, finally, a parabola curve equation is obtained, the voltage and maximum power of the maximum power point are solved, the method eliminates the occurrence of oscillation and misjudgment of a traditional algorithm near the maximum power point, so that a system can accurately track the maximum power, the response time is short, the oscillation is small, and the dynamic error is also smaller.

The invention relates to a soft sensing method for SO2 emission of a power plant based on variable compression BP neural network, comprising the steps of S1, collecting sample data about time variation in a wet flue gas desulfurization system, and determining neurons of an input layer and an output layer of the dynamic neural network according to the collected sample data; 2, performing correlation analysis on that sample data, compressing the original sample variable to remove sample data whose correlation with SO2 in the flue gas at the outlet of the wet flue gas desulfurization system is less than 0.2; Step S3: Compressing by using the variable-BP neural network model wet flue gas desulfurization system, establish wet flue gas desulfurization system prediction model; Step S4, calculating the predicted value of SO2 concentration at the flue gas outlet of the wet flue gas desulfurization system by using the wet flue gas desulfurization prediction model established in the step S3; StepS5: controlling The slurry spraying amount of the wet flue gas desulfurization system by using the predicted value of step S4.

The invention discloses a three-beam all fiber coherent frequency-modulated continuous-wave laser radar. The transmitting and receiving portions of the laser radar use all fiber light paths, the fibers are used as transmitting and receiving light paths of laser, and therefore a light source and a detector can be arranged away from a harsh ambient detection environment. The laser radar also has the advantages of simple structure, light weight and the like. Through utilizing three beams to irradiate a target, the three-dimensional velocity and the distance information can be simultaneously demodulated, and the dynamic error brought by swing is eliminated. A light beam emitted by the light source is divided into two light beams by a first coupler to be transmitted, and then the two light beams are divided into light beams in an X-axis, a Y-axis and a Z-axis for transmission by a second coupler and a circulator, so that the light beams irradiated on the target have three-axis light beam characteristics in a space coordinate system. The laser radar adopts a coherent detection method and a triangular wave frequency-modulated continuous wave system, the distance and speed information can be simultaneously detected, the problems that the distance velocity resolutions of a pulse system are mutually restricted are solved, and the non-blind-spot high-precision measurement is realized. Under the condition that the frequency error is introduced without the difference of lasers, the three-dimensional velocity and distance can be simultaneously measured to obtain the detector posture, and the dynamic error is reduced by 2 to 3 orders of magnitude.

The invention provides a high-sensitivity fiber grating acceleration sensor, which belongs to the technical field of vibration monitoring. The high-sensitivity fiber grating acceleration sensor comprises a measurement substrate A or a measurement substrate B, a rigid beam and a balance spring, wherein the balance position of the rigid beam is basically parallel with the measurement substrate A orbasically vertical to the measurement substrate B; one end of the rigid beam is hinged with a frame body fixedly connected with the measurement substrate A or the measurement substrate B through a rotating shaft, and the other end of the rigid beam is fixed with a mass block; one side of the rigid beam or the mass block is provided with the balance spring for enabling the rigid beam to be in a balance position; one side or two sides of the rigid beam is or re provided with one or two fiber gratings; and when the measurement substrate A or the measurement substrate B vibrates along with a monitored piece, the fiber grating can directly sense the vibration information of the rigid beam. The sensor sensitivity is improved obviously, the transverse sensitivity of the acceleration sensor can beeffectively suppressed, and the high-sensitivity fiber grating acceleration sensor has the advantages of simple structure, durability, not easy damage, small dynamic errors, accurate measurement, high sensitivity, high accuracy and high efficiency.

The invention discloses an in-situ measurement planning method for a high-steepness complex curved surface and belongs to the field of curved surface measurement. According to the method, the non-equidistant transverse section contour lines of a complex curved surface are generated with equiluminous angles adopted as constraint conditions; a full-surface latticed scanning measurement path is obtained based on the longitudinal section contour lines and non-equidistant transverse section contour lines of the complex curved surface; the concave-convex characteristics of the surface are extractedaccording to average curvature changes in two parameter directions, and local encryption scanning contour lines are generated; multi-section splicing measurement motion planning is carried out according to the equiluminous angles and the obtained scanning path, so that the movement trajectory of the reference point of a sensor is obtained; and finally, the measurement deflection angle of an optical measuring head is detected, so that the in-situ measurement planning of the complex curved surface is completed. With the method adopted, the in-place scanning path generation and measurement motionplanning of the high-steepness complex curved surface are achieved; the measurement precision of a characteristic area is guaranteed; and dynamic measurement errors caused by the multi-axis linkage of a machine tool are reduced. The method is reliable and high in universality.

The invention relates to a response time calibration technology of a temperature sensor, and specifically relates to a response time calibration device of a temperature sensor. The response time calibration device of the temperature sensor solves the problems that calibration precision is low when an existing response time calibration method of a temperature sensor calibrates a small-response-time temperature sensor, reliable response time cannot be obtained, and accuracy of response time obtained in a flame temperature field environment is low. The response time calibration device of the temperature sensor comprises a longitudinal linear guide rail, a slide block with a pulley, a vertical small baffle plate, a vertical big baffle plate, a rapid adsorption sheet, a rapid ejection device, a temperature sensor, a compensation lead, a signal acquisition and processing integration circuit, a data transmission line, a data display device and a flame temperature source. The response time calibration device is suitable for performing response time calibrations of the temperature sensor in various environments, and is especially suitable for performing the response time calibration of the temperature sensor in the flame temperature field environment.

The invention discloses a decoupling servo control loop system and method for a two-axis integrated gyro accelerometer. The decoupled servo control loop is a servo control loop for the two-axis integrated gyro accelerometer. The decoupling servo control loop system and method for the two-axis integrated gyro accelerometer comprises a two-input / output decoupler, a gain compensator, two identical second-order integral modules and two identical lead lag modules, which can realize decoupling of two interlinking loops; the second-order integral modules can eliminate errors associated with the change rate of the constant angular velocity, thereby improving the steady-state accuracy of the servo loop system; and the lag lead can link can improve the dynamic gain of the low-frequency band of the system, which is beneficial to reducing dynamic errors. The output decoupling link is added in the servo control loop, which can overcome the interlinking problem between the two current output valuesof the servo loop and the angular velocity, and improve the output precision of the gyro accelerometer system.

The invention discloses a DEM (Dynamic Element Matching) encoding method for a current rudder DAC (digital to analog converter), relating to the field of DEM encoding. The method comprises the following steps of: judging the size relation between the digital Input (n) of the current period of the current rudder DAC and the digital Input (n-1) of the last period of the current rudder DAC; if the digital Input (n) is equal to the digital Input (n-1), keeping output of a DEM module unchanged, and keeping Pstart and Pend values of a printer unchanged; if the digital Input (n) is more than the digital Input (n-1), carrying out first setting operation on the output of the DEM module, and correcting the Pstart and Pend values; and if the digital Input (n) is less than the digital Input (n-1), carrying out second setting operation, and correcting the Pstart and Pend values. According to the method disclosed by the invention, the hop switching number of each period is effectively reduced, and therefore dynamic errors caused by switch hop is reduced.

The invention discloses a vehicle pull line type displacement measuring device. The device comprises a pull line type displacement sensor, a first moving component, a second moving component and a locking mechanism. The first moving component includes a first guiding component and a first moving component which moves along the first guiding component. The second moving component comprises a second guiding component and a second moving component which moves along the second guiding component. The pull line type displacement sensor is installed on the second moving component. The second guiding component is installed on the first moving component. Moving directions of the first moving component and the second moving component are vertical. The first guiding component is installed on a locking mechanism. In the invention, through mutual slide between a rolling bearing and a bearing guide rail, and between a guide rail slide block and a linear optical axis, vertical and transverse degrees of freedom are possessed; during a dynamic displacement test process, a sensor pull line can be ensured to be basically consistent with a vertical direction of a vehicle so as to reduce a dynamic error caused by vehicle pitch and roll to the maximum extent, and improve displacement test accuracy.

The invention relates to an elastic wave pick-up device for reducing phase difference interference. The device is composed of a metal support, a limit cassette, a rubber blanket, an elastic spring and a sensor screw. The limit cassette is painted with a special coupling agent and is inserted into the metal support. A sensor is inserted into the limit cassette. The rubber blanket and the elastic spring are put between the sensor and a cover body of the metal support. The metal support, the limit cassette, the elastic spring and the rubber blanket are successively installed in order and maintained to be concentric and parallel to each other. The part where the limit cassette and the metal support are contacted is filled with a coupling agent. The part where the sensor and the limit cassette are contacted is filled with a coupling agent. The sensor screw and the sensor are fixed as a whole, and the sensor screw's tip is ground to be arc-shaped. The invention has the following beneficial effects: through reducing contact area between the sensor and the test surface, phase difference interference generated by the sensor when the sensor picks-up elastic waves is reduced, and impact-echo pick-up precision is enhanced.

The invention relates to a combined type spherical frame for an inertial stabilization platform, which is composed of an integrated body structure, 2N cambered structures and two spherical structures, wherein a shaft end assembly is mounted on the integrated body structure, and no splicing on the mounting surface of the shaft end assembly is ensured by adopting the integrated structure type, thereby being favorable for ensuring the mounting accuracy of the shaft end assembly and reducing the form and position error; the 2N cambered structures can be disassembled relative to the body structure so as to facilitate mounting or disassembly of effective loads in the spherical frame, thereby realizing the miniaturization of the inertial stabilization platform structure; and the two spherical structures realize the equal stiffness design of the spherical frame, thereby reducing the second-order disturbance torque caused by the non-equal stiffness design. The spherical frame provided by the invention can ensure the mounting accuracy of the shaft end assembly to the maximum limit and reduce the dynamic error, thereby increasing the torque disturbance resisting capability of the frame, effectively reducing the rotary volume occupied by the frame, and realizing high accuracy, high stability and miniaturization of the inertial stabilization platform.

The invention discloses an in-situ measurement planning method for a high-steepness complex curved surface and belongs to the field of curved surface measurement. According to the method, the non-equidistant transverse section contour lines of a complex curved surface are generated with equiluminous angles adopted as constraint conditions; a full-surface latticed scanning measurement path is obtained based on the longitudinal section contour lines and non-equidistant transverse section contour lines of the complex curved surface; the concave-convex characteristics of the surface are extractedaccording to average curvature changes in two parameter directions, and local encryption scanning contour lines are generated; multi-section splicing measurement motion planning is carried out according to the equiluminous angles and the obtained scanning path, so that the movement trajectory of the reference point of a sensor is obtained; and finally, the measurement deflection angle of an optical measuring head is detected, so that the in-situ measurement planning of the complex curved surface is completed. With the method adopted, the in-place scanning path generation and measurement motionplanning of the high-steepness complex curved surface are achieved; the measurement precision of a characteristic area is guaranteed; and dynamic measurement errors caused by the multi-axis linkage of a machine tool are reduced. The method is reliable and high in universality.

The invention discloses a semi-active control method of an energy reclaiming type semi-active suspension system. The semi-active control method is characterized by obtaining an ideal electromagnetic damping force Fref required to be output by a linear motor through a skyhook and groudhook suspension damping semi-active control strategy; dividing the ideal electromagnetic damping force Fref by an electromagnetic damping coefficient ki, thus obtaining a needed reference current iref; collecting a real current value ireal in a motor winding through a current sensor; inputting a difference value e of the reference current iref and the real current value ireal and a difference value change rate ec into a fuzzy-PI (Proportion Integration) mixed controller; outputting two paths of pulse signals by the fuzzy-PI mixed controller to control the switching on and off of an MOS (Metal Oxide Semiconductor) transistor in a semi-active control circuit, thus realizing semi-active control.

The invention discloses a dynamic position and attitude synchronization measurement method fused with inertial measurement information, which comprises the following steps: rigidly connecting an IMU (Inertial Measurement Unit) with a pose measurement target formed by a wMPS photoelectric receiver, respectively measuring the spherical center coordinates of the photoelectric receiver by using a three-coordinate measuring machine, fitting the coordinate system of the IMU, and unifying the observation objects of the wMPS and the IMU; placing the rigidly connected pose measurement target on a measured target and moving along with the target, measuring the scanning angle of each receiver by using the laser emission station, and constructing a light plane geometric constraint relationship; the wMPS pose observation at the initial position is used as an IMU state updating initial value, and the IMU state is updated successively by using the angular velocity and the acceleration output by the IMU; and if a new wMPS measurement result exists in two adjacent IMU state updating processes, performing wMPS and IMU pose measurement data fusion to obtain a fused system state quantity, and outputting a final pose in combination with IMU self updating.

The invention relates to a double hydraulic cylinder flow compensation synchronous erection device and a control method thereof. The double hydraulic cylinder flow compensation synchronous erection device is mainly composed of hydraulic cylinders, piston rods, an oil pump, servo valves, an oil tank, displacement sensors, controllers, an overflow valve, a computer and the like. The first displacement sensor and the second displacement sensor detect the displacement of the first piston rod and the second piston rod, a detection result is converted through an AD converter, data are transmitted tothe computer, the difference between the displacement of the first displacement sensor and the displacement of the second displacement sensor is calculated by the computer, and the result is sent tothe first controller and the second controller through a DA converter; according to the displacement difference of the first piston rod and the second piston rod, the size of valve elements of the first servo valve and the second servo valve is adjusted many times, so that the flow of the valve elements of the first servo valve and the second servo valve can be changed till the displacement difference of the first piston rod and the second piston rod is zero. The double hydraulic cylinder flow compensation synchronous erection device and the control method thereof solve the problems that a flow dividing synchronous device is poor in eccentric load resisting capacity, low in synchronizing precision and poor in reliability, improve the synchronizing precision and the responding speed, and improve safety and stability.

The invention relates to a method for follow-up testing of temperature of a steel billet in a furnace, which comprises the steps of primary preparation and the steps of follow-up testing in the furnace. The primary preparation comprises the following concrete steps: (1) drilling a hole on the steel billet to be tested; (2) inserting the hot end part of a thermocouple into the hole drilled in the step (1), and enabling the hot end of the thermocouple to be in contact with the bottom of the hole; filling and compressing the residual space in the hole by the iron powder of which the material is the same as the material of the steel billet to be tested; and (3) connecting the measuring end of the thermocouple to a temperature recorder, enabling the temperature recorder and the steel billet to together enter the furnace, and then, carrying out the steps of follow-up testing in the furnace. The method of the invention can improve the accuracy and the reliability of temperature testing of the steel billet.

The invention discloses a triaxial movement platform, comprising a base, a Y axis movement system assembled at two ends of the base, an X axis movement system erected in the middle of the base and a Z axis movement system fixed on the X axis movement system, wherein, the X movement system, the Y movement system and the Z axis movement system respectively comprise a linear motor and a sliding device, which comprises a lead rail and a sliding block; the X axis movement system also comprises a cross beam, on which the linear motor used for driving the X axis movement system and the lead rail arefixed; the Z axis movement system also comprises a fixed bracket, on which the linear motor used for the Z axis movement system and the lead rail are installed. The triaxial movement platform not only can improve the system operation stability and accuracy but also can realize the high speed and accurate positioning of load.

The invention relates to a charging and weighing system for a cream production line. The system comprises a powder material charging and weighing device and a liquid material charging and weighing device; the powder material charging and weighing device comprises powder material storage tanks, a spiral propelling mechanism, a weighing trolley and a variable-frequency motor; the initial end of the spiral propelling mechanism is horizontally and fixedly arranged at the lower part of the powder material storage tank, the variable-frequency motor is used for driving the spiral propelling mechanism; the lower part of the tail end of the spiral propelling mechanism is in butt joint with a feeding hole of the weighing trolley; the weighing trolley is in matched butt joint with a row of corresponding powder material storage tanks above a horizontal track; the weighing trolley is in signal connection with a PLC of the variable-frequency motor, the variable-frequency motor gradually decelerates according to a weighing signal, and the weighing trolley stops rotation after reaching a target weight; the liquid material charging and weighing device comprises liquid material storage tanks and pipeline type mass flowmeters which are connected with each other; and an electromagnetic stop valve is arranged at the tail end of the pipeline of each pipeline type mass flowmeter, and the opening and closing of the electromagnetic stop valve respectively control the operation and stop of liquid material charging.

The invention discloses a three-beam all fiber coherent frequency-modulated continuous-wave laser radar. The transmitting and receiving portions of the laser radar use all fiber light paths, the fibers are used as transmitting and receiving light paths of laser, and therefore a light source and a detector can be arranged away from a harsh ambient detection environment. The laser radar also has the advantages of simple structure, light weight and the like. Through utilizing three beams to irradiate a target, the three-dimensional velocity and the distance information can be simultaneously demodulated, and the dynamic error brought by swing is eliminated. A light beam emitted by the light source is divided into two light beams by a first coupler to be transmitted, and then the two light beams are divided into light beams in an X-axis, a Y-axis and a Z-axis for transmission by a second coupler and a circulator, so that the light beams irradiated on the target have three-axis light beam characteristics in a space coordinate system. The laser radar adopts a coherent detection method and a triangular wave frequency-modulated continuous wave system, the distance and speed information can be simultaneously detected, the problems that the distance velocity resolutions of a pulse system are mutually restricted are solved, and the non-blind-spot high-precision measurement is realized. Under the condition that the frequency error is introduced without the difference of lasers, the three-dimensional velocity and distance can be simultaneously measured to obtain the detector posture, and the dynamic error is reduced by 2 to 3 orders of magnitude.

The invention discloses a two-axis integrated gyro accelerometer decoupling servo control loop system and method. The decoupling servo control loop is a servo control loop for a two-axis integrated gyro accelerometer. A two-axis integrated gyro accelerometer decoupling servo control loop system designed by the present invention includes a two-input-output decoupler, a gain compensator, two identical second-order integral modules and two identical lead-lag modules, which can realize For the decoupling of the two interlinkage loops, the second-order integral module can eliminate errors related to the rate of change of constant angular velocity, thereby improving the steady-state accuracy of the servo loop system; the lag-lead link can improve the dynamic gain of the system in the low-frequency band, which is beneficial to Reduce dynamic errors. Adding an output decoupling link in the servo control loop can overcome the cross-linking problem between the two current output values ​​of the servo loop and the angular velocity, and improve the output accuracy of the gyro accelerometer system.

The invention relates to a fixing method for a sheathed thermocouple, comprising the following steps of 1) self-checking a welding seam to be qualified after finishing the welding construction of base metal; 2) cutting out a section of welding wire made of a material same as that of the welding seam of the base metal; 3) spot welding one end of the welding wire cut in the step 2) on the surface, of which the temperature is to be measured, of the welding seam, wherein the welding wire used when a welding machine is used for spot welding is made of a material same as that of the cut welding wire; placing the hot end of the sheathed thermocouple on the middle position of the welding wire, and spot welding the other end of the welding wire on the surface of which the temperature is to be measured so as to ensure that the hot end of the thermocouple is pressed by the welding wire; 4) carrying out thermal treatment on the welding wire; and 5) polishing the spot welding part of the welding wire by using a polishing machine after finishing thermal treatment to flatten the surface of the welding seam. By using the method disclosed by the invention, the phenomenon that the material on the surface of the welding seam is nonuniform because the surface of the welding seam can generate a dissimilar material is overcome, and the problem of temperature measurement inaccuracy caused by the infirm contact between the hot end of the thermocouple and the part of which the temperature is to be measured is solved.

The invention describes a sensor coupling device and a damping debugging method suitable for vibration / fluctuation testing, including a headgear, a card holder arranged in the headgear, and a base fixed at the lower end of the headgear. Both the headgear and the holder are cavity structures, and the lower end of the headgear is open The upper and lower surfaces of the deck are open, and the deck is clamped in the inner cavity of the headgear; the inner wall of the deck is coated with a couplant connected with the sensor; the upper surface of the base is provided with a hole for the lower end of the sensor to pass through. It also includes a coupling agent arranged between the outer wall of the card seat and the inner wall of the headgear. In the present invention, the setting of the card seat provides a lateral damping for the sensor and limits the lateral displacement of the sensor, and the couplant filled between the inner wall of the base and the sensor and the outer wall of the card seat and the inner wall of the headgear does not reduce the sensor and sensor. The viscosity of the test system is increased under the premise of rigid contact of the measured object, the frequency response range of the test system is improved, and the dynamic error is reduced.