200results about How to "Accurate control precision" patented technology

The invention relates to a current predictive control method of a permanent magnet synchronous motor, which belongs to the electric control field. The dynamic response speed and the control accuracy for the stator current control of the permanent magnet synchronous motor are improved through stator current prediction and deadbeat control, and the system delaying is compensated, so that the noise and the torque ripple of the motor in operation are reduced. The method comprises the steps as follows: obtaining a three phase stator current signal, and the electrical angle and the electrical angular speed of the motor rotor through the technologies of sensor sampling and a photoelectric coded disc or position sensorless detection; carrying out Clarke transformation and Park transformation on the stator current signal to obtain the stator current in a synchronous revolution dq coordinate system; substituting the obtained stator current signal in the dq coordinate system into a control equation of a current predictive controller of the permanent magnet synchronous motor, carrying out deadbeat control according to the given value of the obtained stator current in the dq coordinate system in an outer ring controller to obtain a stator voltage vector in the dq coordinate system; carrying out Park inverse transformation on the obtained stator voltage vector in the dq coordinate system, to obtain a pulse-width modulation (PWM) control signal of an inverter by a space vector pulse width modulation (SVPWM) method, controlling the stator current through the inverter, and then implementing the current predictive control over the permanent magnet synchronous motor.

The invention provides a portable hip joint assisting mechanism. A left waist support and a right waist support are the same in structure, i.e., both of an L-shaped structure. One ends of the left waist support and the right waist support are fixedly connected to two sides of a waist adjusting mechanism by means of connecting flanges. Two back support plates are fastened and connected to side surfaces of the left waist support and the right waist support by means of screws, and both perpendicular to the waist supports. Two support connecting rods arranged in parallel up and down are in threaded connection with the back support plates. A control box is suspended to the support connecting rods. A waist belt passes through sleeve holes in the middle portions of the back support plates. Hip driving mechanisms are located at lower sides of the waist supports and in threaded connection with the other ends of the left waist support and the right waist support by means of connecting shafts. A joint execution mechanism is formed by a first thigh connecting rod, a second thigh connecting rod, a first thigh binding band and a second thigh binding band. The portable hip joint assisting mechanism provides a motor-driven hip joint assisting mechanism for providing extra torque with the requirements of simple structure, low weight, safety and controllability and high practical and economical values on the mechanism.

The invention discloses a central air conditioning fuzzy PID control system based on load prediction control. The system comprises a load prediction module, a fuzzy PID control module, an executor, acontrolled object and a sensor. The load prediction module is composed of three load prediction units including the medium-term load prediction unit, the short-term load prediction unit and the flow prediction unit. A load prediction controller calculates the required chilled water flow of a current chilled water system according to history operating data and an outdoor temperature, then the required frequency of a chilled water pump is calculated by means of the intelligent fuzzy PID control system, finally, the rotating speed of the water pump is changed through a water pump frequency changer, variable flow control of central air conditioning chilled water is completed, and therefore, the system has the energy-saving benefit. By means of the refrigeration house temperature feedforward-fuzzy control system based on dynamic load variation and the control method, the phenomena that temperature control through a traditional central air conditioning system chilled water control scheme lags, and the control precision is not high are avoided, early response of a flow control system is achieved, and the performance of a central air conditioning system is guaranteed.

The invention discloses a control method of a driving system of a permanent magnet synchronous motor of an electrical automobile considering iron loss, and provides a control method of a driving system of a permanent magnetic synchronous motor considering iron loss based on a self-adaptive fuzzy backstepping method, which solves the non-linear problem of the power driving and control system of the motor of the electrical automobile, enables the motor to quickly reach the stable running state and is more suitable for the control objects requiring quick dynamic response, such as the driving system of the electrical automobile. The control rules u[d] and u[q] only adopt one self-adaptive parameter theta, so as to reduce the calculation amount. The method has the advantages that the problem of position tracking and control of the permanent magnet synchronous motor considering the iron loss under the conditions of orienting to the site and having undetermined parameter and load torque disturbance is solved; the fuzzy logic system is used for approximating to the unknown non-linear item, and the self-adaptive fuzzy backstepping method is used for enabling the tracking error to approximate to 0; the more accurate control precision is reached, and the ideal position tracking and control effect is ensured.

The invention relates to a coater scraper apparatus. The apparatus comprises a scraper rack connected to a coater frame, a scarper having a cutting edge corresponding the coating roller of a coater is press-fitted on the scraper rack through a scraper press plate, a scraper rack adjusting shaft paralleling to the scraper rack is movably arranged on the coater frame in a penetrating mode, the scraper rack is connected with the scraper rack adjusting shaft and rotate around the scraper rack adjusting shaft, an adjusting worm gear is fixedly connected with the scraper rack adjusting shaft in a penetrating mode, the coater frame supports an adjusting worm having a driving cooperation with the adjusting worm gear, and the adjusting worm is connected with a hand wheel. The coater scraper apparatus accurately controls the adjustment between the scraper and the coating roller by adopting the scraper rack rotatablely far from or close to the coating roller and combining the scraper adjusting seat and a trimming cylinder, so the apparatus has the advantages of simple and compact structure, convenient and accurate adjustment, and effective ensure of the thickness of a glue solution on the coating roller for the uniform adjustment, and is suitable for the use of various different specification coating rollers and coating thicknesses.

The invention discloses a glass heating graphite mold and a production method thereof. The mold comprises a front mold and a rear mold, wherein the front mold comprises a front mold base and a front mold core made of a graphite material; the rear mold comprises a rear mold base and a rear mold core made of the graphite material; a cavity matched with the front mold core is formed in the front mold base; the front mold core is arranged in the cavity of the front mold base; a cavity matched with the rear mold core is formed in the rear mold base; the rear mold core is arranged in the cavity of the rear mold base; intermediate areas of opposite surfaces of the front mold core and the rear mold core are three dimensional curved surfaces suitable for processing to obtain hot bending glass during mold closing; edge areas of the opposite surfaces of the front mold core and the rear mold core are respectively provided with a plurality of supporting insert via holes; supporting inserts are arranged in the supporting insert via holes; when the mold is closed, the supporting inserts, which are oppositely arranged, on the front mold core and the rear mold core, make contact with one another, so that the effects of positioning and supporting the mold cores are realized, and the pressures of the mold cores are borne. According to the glass heating graphite mold disclosed by the invention, large-scale mass production is easily realized while the molding quality of the graphite mold is improved.

The invention discloses a control method of full-life periodical processing precision of a mould, and relates to a processing control method of the mould. The control method comprises the following steps of: S1, designing a three-dimensional CAD (Computer-Aided Design) mode of the mould; S2, manufacturing a Styrofoam mode; S3, acquiring the curved surface data of the Styrofoam mode; S4, comparing with the three-dimensional CAD mode of the mould cast piece to judge whether the size is out of tolerance; S5, acquiring the curved surface data of the cast piece; S6, comparing with the three-dimensional CAD mode of the mould to judge whether the size is out of tolerance; S7, acquiring the mechanical processing curved surface data; S8, comparing with the three-dimensional CAD mode of the mould to determine the processing position and the processing quantity of a tongman; S9, acquiring the curved surface data of the mould; S10, comparing with the three-dimensional CAD mode of the mould to provide the design experience for the mould designers; S11, acquiring the actual used curved surface data; and S12, comparing with the curved surface digifax E of the mould to determine the time for modifying the mould. The control method can improve the manufacture precision of the mould and can reduce the manufacturing time of the mould, so that the control method is especially applied to the mould by which the metal plates are directly manufactured as covers.

The invention discloses an electrolyte-plasma polishing technique for a stainless steel precise structural part. The electrolyte-plasma polishing technique for the stainless steel precise structural part comprises the following steps that (1) 0.01-0.03 mm technological allowance is set before the stainless steel precise structural part is polished; (2) the stainless steel precise structural part is installed on a special polishing tool, the tool comprises an insertion plate and steel sheets, a plurality of sliding grooves are formed in the insertion plate, one steel sheet is installed in each sliding groove, the steel sheets can slide horizontally along the sliding grooves, the structural part to be polished is fixedly arranged at the lower ends of the steel sheets, the clamping surface of the tool makes close contact with the surface of the structural part, and ablation of the surface of the part caused by abnormal discharging is prevented; (3) ammonium sulfate polishing liquid with the concentration being 2%-4% is added into an electrolytic bath, and the temperature of the polishing liquid is controlled between 80 DEG C and 95 DEG C; and (4) the structural part which is clamped through the tool in the step (2) is placed in the polishing liquid in the step (3), and polishing is conducted through direct currents for 2-10 min.

The invention discloses a command filtering-based synchronous motor neural network back-stepping discrete control method. In order to solve the problem that a permanent magnet synchronous motor has many variables and strong coupling, and is easily affected by external load and motor related parameter changes, a neural network adaptive controller is designed based on a command filtering technologyand the principle of a back-stepping method; the neural network technology is used to approximate unknown nonlinear terms; the adaptive back-stepping method is applied to the design of the controller;and the command filtering technology is used to solve the problem of computation explosion. According to the method of the invention, complete controller design which is absent in a traditional method is supplemented, so that Lyapunov stability analysis is improved; after being subjected to the control and adjustment of the controller, the operation of a motor can quickly reach a steady state, sothat the motor is more suitable for a control object requiring fast dynamic response; and simulation results show that the novel controller overcomes the influence of parameter inaccuracy, ensures anideal control effect, and achieves the fast and stable tracking of a position.

The invention relates to a seamless switching system and a seamless switching method for ensuring normal broadcast of audio. The seamless switching system for ensuring the normal broadcast of audio comprises two video and audio broadcast servers, wherein the video and audio broadcast server comprises a video and audio I/O (Input/Output) board card, a board card drive program, a fault detecting device, an operating system and a video and audio broadcast application program; the video and audio I/O board card comprises a board card hardware buffer cache, a board card hardware register, a board card hardware control module, a signal input interface, a signal main output port and a signal spare output port. According to the seamless switching system and the seamless switching method for ensuring normal broadcast of audio, the switching is performed in video frames, the accuracy of switching frame can be accurately controlled, when in switching period, the signal is broadcasted without appearance of green screen and flickering, repeated frames or frame skipping does not appear, and thus the seamless switching of the spare broadcast signal when a fault appears is achieved.

The invention provides a method for estimating an error in numerical control processing, and the method can be used for solving the problems in an existing error estimation method. On the basis of the original method, the method provided by the invention comprises the following steps of: firstly determining a unit tangent vector of each point according to a cutter center track obtained by an NC code guided out from CAM (Computer Aided Manufacturing) software; then combining the cutter radius, cutter center coordinates and the determined tangent vector of each point to perform back calculation, thus obtaining a practicable curvilinear path of processing; and finally calculating an arch height error according to the practical curvilinear path obtained through calculation. According to the method provided by the invention, the error is estimated according to the practicable curvilinear path, thus the processing precision can be judged more accurately, the processing quality is improved, and a visual and effective reference basis is provided for selection of technological parameters of a complex curved surface finishing process.

The invention provides a testing device and testing method for measuring the road surface friction attenuation rate of a snow-melting agent under the low-temperature environment .The testing device is composed of a testing box and a road surface friction coefficient measuring device .The road surface friction attenuation rate of the snow-melting agent under the low-temperature environment is measured by building a road surface testing table and controlling the temperature in the testing box .The testing device is used in the testing method .The method includes the three steps of test preparation, measurement and result sorting .Testing results obtained through the testing device and the testing method are accurate, stable and reliable and can truly reflect changes of anti-slip performance of a road surface after the snow-melting agent is used, advantages are remarkable, and the preferential road snow-melting agent plays an important role in improving road driving safety and reducing traffic accidents.

The invention discloses a control device for a solar heat-collecting project, which comprises a plurality of solar heat-collecting devices, wherein each solar heat-collecting device is respectively configured with a single chip controller and further comprises a master monitor-management server and a user access platform; the master monitor-management server is in series connection with a network exchanger, and the network exchanger is in communication connection with each single chip controller through the Internet network; the user access platform is in series connection with a gateway router, and the gateway router is interacted with the master monitor-management server through the Internet network; the master monitor-management server comprises a network controller, a webpage information publisher and a water heater parameter monitor; and therefore, the internet is used by the control device to perform centralized single-wire remote monitor on the solar heat-collecting device installed in large area through the webpage, the degree of automation is high and the operation is convenient.

The embodiment of the invention discloses a parcel sorting method and system. Parcels are positioned based on a visual imaging system to obtain imaging information of the parcels, then the coordinaterange correspondingly to each parcel is obtained through the data processing of a control device, according to the location distribution of each parcel on a separator, an appropriate scheduling strategy is used combined with the performance of the separator, and finally the scheduling strategy is sent to the control device to separate the parcels. The method is more accurate in control accuracy and processing throughout than a traditional way through the visual system, and it is not necessary to control the position situation of the parcels flowing into a first conveyor belt in advance by human intervention; and meanwhile the distribution labor cost of a current logistics company in the sorting process can be saved, after the integration of the whole device, the maintenance and improvementin the later stage are also convenient, and the degree of automation of the logistics can be improved.

The invention discloses an automatic exposure method for an LED white-light source. The method includes the steps that first, the brightness of a current video is acquired, and the difference value between the brightness of the current video and preset video brightness is calculated; second, whether the difference value is within a preset range is judged, and if not, the f-number and the shutter speed are adjusted according to the difference value so that automatic exposure can be performed; third, the first step and the second step are executed again, whether the f-number and the shutter speed are adjusted to preset threshold values is judged, if yes, the driving current and an automatic gain value of the LED white-light source are adjusted alternately till the next threshold value is achieved, automatic exposure is performed after the driving current or the automatic gain value of the LED white-light source is adjusted every time, and the third step is continued till the video ends. The invention further discloses an automatic exposure device for the LED white-light source. Due to the method and devoice, the control accuracy of automatic exposure is more accurate, and the quality effect of the video is effectively guaranteed.

The invention relates to a motor torque ripple test bench and a test method, a synchronous belt transmission structure is arranged, and the precision of the rotation position of a rotor is accuratelycontrolled through a large belt wheel. Through multi-position stalling, the torque ripple condition of the rotor in one cycle can be obtained; a torque sensor is used in a low-frequency region, and anangular acceleration sensor is used in a high-frequency region, so the measurement range of cogging torque is expanded; the method is suitable for measuring the cogging torque of the full-frequency region of the motor. According to the test bench, the locked-rotor and inertia loading are combined, the torque ripple condition of the motor in a rotation period can be represented through a locked-rotor method on one test bench, and the cogging torque ripple condition of the motor can also be directly tested. And the torque ripple influence of the dynamometer can be reduced as much as possible through the large-inertia flywheel. In addition, the elastic coupling is adopted to eliminate the influence of coaxiality, the eccentricity and vibration in the transmission chain on the sensor side, and the sensor is prevented from being damaged due to vibration.

The invention is a diffusion welding multilayer structure diaphragm capsule, belonging to the field of diaphragm capsule manufacturing. By adopting the methods of diffusion welding, machining and shaping, the manufacturing of diaphragm capsule in the invention can be realized. The main procedures include thin wall blank preparation, surface cleaning, surface modified treatment, welding-stopping treatment, diffusion welding, machining, shaping and the like. Compared with the multilayer structure diaphragm capsule manufactured by other methods, the multilayer structure diaphragm capsule manufactured by the invention has the advantages of fine fatigue property (above 1 million times), strong pressurization performance, adjustable rigidity, high compression ratio (higher than 80%), capability of micromation of inner holes, high precision of geometric dimensions, strong destabilization resistance, precise and controllable weldingline profile, adjustable width of weldingline and the like. By using the invention, the diaphragm capsule in the shape of circle, square and other shapes can be manufactured, and can serve as a compensation element of displacement and angle in hydraulic, barometric, transferring pipeline installation, an elastic compensation element and a pore damping element as well as a measuring element for a manometer and an altimeter; besides, the diaphragm capsule can be also used as a heat transferring finned tube for air conditioning, refrigeration and other devices as well as a metal capsule of separating gas or liquid for an accumulator and a storage box. The invention can provide multilayer structure diaphragm capsule products with fine performance for related industries.

The invention discloses a process design method for milling precision consistency, and belongs to the technical field of milling cutters. Due to the fact that in the prior art, design indexes are incomplete, targets are unclear, accurate control over error distribution of the machined surface cannot be achieved, and the milling process design method is improved aiming at the problems. According tothe method, evaluation indexes of processing precision evaluation are increased, and precise control of processing error distribution is realized. The method comprises: designing a milling vibrationtest, extracting vibration test data, carrying out whole-process dynamic detection on milling vibration, and analyzing the milling vibration and the machining precision by using an improved grey correlation analysis algorithm; and analyzing the dynamic change of each parameter of the precision of the machined surface along with the cutting stroke through a grey correlation algorithm. According tothe process design method, the optimization design, the dynamic design and the collaborative design are comprehensively applied, the original process design method is optimized through the evaluationmethod for the precision consistency of the machined surface, and the machining precision and the consistency level of the machining precision are improved.

The invention relates to a true triaxial multifunctional large deep mine laneway model testing machine, which comprises a doughnut shape-like framework system, a hydraulic loading and pressure preserving system, a control system, a pressure water system, an equipment base system and a model dismounting system. The true triaxial multifunctional large deep mine laneway model testing machine is characterized in that the doughnut shape-like framework system is a full sealing structure and can perform the true triaxial five-face and three-directional loading, provide higher model surface stress, preserve high pressure for a long time and carry out the water-yield pressure preserving test. The true triaxial multifunctional large deep mine laneway model testing machine is applicable to multiple scientific studies of the deep mine laneway, and achieve the simulation tests of mutual influences of excavation, supporting, tunneling, water inrush, and high floor pressure, and others of the underground laneway project; the testing machine has the advantages of being compact and simple in structure, convenient to operate, and environment-friendly and energy-saving.