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

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 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 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 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 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 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 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 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 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 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, which relates to the digital signal processing technology field, discloses a digital analog converter (DAC) and a digital analog conversion method. The structure of the digital analog converter is a complete binary tree with n+1 layers; a root node of the complete binary tree is connected with an input terminal of digital signal data of (n+1) bits. Besides, the complete binary tree has 2 <n> leaf nodes and each of the leaf node is a one-bit DAC unit; other node except the leaf nodes in the complete binary tree are coding submodules; and output terminals of the 2 <n> leaf nodes are connected with an accumulator. According to the invention, the DAC and a dynamic element matching (DEM) coding conversion scheme based on the DAC in the method are employed; therefore, too much switch jumping during the implementation of the digital analog conversion method can be reduced; and an effect of reduction of dynamic errors is realized; and moreover, outputting of DEM coding has certain randomness, so that distortion caused by mismatching can be converted into noises.