162results about How to "Reduce the frequency of movements" patented technology

The invention discloses a controlling method and device for a wind generating set. Under the conduction that the measuring rotational speed of generators is larger than a rated rotational speed, and measuring power surpasses rated power, torque is converted into a constant power control mode from a variable parameter PI control mode; under the condition that a variable pitch angle is smaller than an optimal variable pitch angle, and the measuring rotational speed decreases under the rated rotational speed, the torque is converted into the variable parameter PI control mode from the constant power control mode; the variable pitch angle is controlled by adopting a PI control parameter nonlinear adjusting mode; variable pitch control is in activation state within whole normal work speed range. The scheme can realize flexible switch of control states, ensures the stability of generator set operation and power output, adopts variable parameter PI control on the torque, can efficiently enhance torque controlling force in transition section, reduces action frequency and spectrum of the variable pitch in the section, and reduces generating capacity loss and system loading caused by the advanced action of the variable pitch before the wind generating set is in fully loaded running.

The invention provides a novel resonant DC-link soft switching inverter and a modulation method thereof, and relates to the technical field of inverters. The inverter comprises an auxiliary resonant circuit, an inverter bridge, a load circuit and a DC power supply, wherein the auxiliary resonant circuit comprises a bus switch tube, two auxiliary switch tubes, two auxiliary resonant inductors, a primary resonant capacitor, two auxiliary resonant capacitors, an anti-parallel diode of the bus switch tube and four auxiliary diodes; the inverter bridge is of a three-phase bridge structure; the load circuit is a three-phase resistor-inductance load; and various main power switch tubes of the inverter bridge work in manners of sine pulse width modulation and complementary turn-on at a phase difference of 180 degrees. According to the novel resonant DC-link soft switching inverter, a zero-crossing reverse process of current of each auxiliary resonant inductor is avoided, the service life of the inverter is prolonged, and the current stress of the auxiliary switch tubes of the inverter, the conduction loss of the auxiliary resonant circuit and the switching losses of the bus switch tube and the auxiliary switch tubes are effectively reduced.

The invention mainly provides an auto-disturbance rejection control method with disturbance compensation and finite time convergence, which includes two parts such as disturbance compensation and finite time convergence, wherein the disturbance compensation is to introduce a dead zone and an anti-saturation link into the control rate design and compensate the error disturbance through an observerso as to suppress load disturbance; and the finite time convergence is to design an auto-disturbance rejection error feedback control rate based on finite time convergence.

The invention discloses a dual-active full-bridge converter-based hybrid energy storage system and a control method therefor. The hybrid energy storage system comprises a supercapacitor, a lithium battery, a dual-active full-bridge converter, a Buck/Boost bidirectional converter and a direct current bus; and two kinds of energy storage equipment form a cascading type hybrid energy storage system. The supercapacitor is connected with the direct current bus through the dual-active full-bridge converter; by adoption of phase-shifting closed-loop control and by collecting the voltage information of the direct current bus, the output power of the hybrid energy storage system can be automatically regulated so as to stabilize the voltage of the direct current bus; the lithium battery is connected with the supercapacitor through the Buck/Boost bidirectional converter; and by adoption of voltage and current dual-closed-loop control, and by collecting the voltage of the supercapacitor, automatic charging and discharging of the lithium battery can be controlled, so that the voltage of the supercapacitor can be maintained within a working voltage range, so as to perform indirect compensation to power fluctuation of a direct current microgrid, reduce action frequency of the lithium battery, and effectively prolong the service life.

The invention discloses a wind alignment method of a wind generator yaw system. The method comprises the steps that a current yaw starting angle parameter is obtained through current wind speed according to the functional relationship between the wind speed and a yaw starting angle by a yaw system; and when a deviation angle between a wind generator bin and the wind direction is judged to be larger than the current yaw starting angle by the yaw system, the yaw system controls the wind generator bin to yaw. According to the wind alignment method, the yaw starting angle is set according to the current wind speed, so that yaw starting control is more precise; the action frequency of the yaw system is effectively lowered; abrasion of yaw gears is reduced; yaw fatigue is alleviated; and the generation capacity of the wind generator is improved.

The invention discloses a mixed SVPWM control method used for a three-phase grid-connected inverter. Based on a three-phase PWM wave controller, control is carried out according to the following three-phase PWM wave: in an alpha beta voltage vector distribution coordinate system, dividing twelve 30-degree sectors, and naming each sector with a number sequentially; defining first, fourth, fifth, eighth, ninth and twelfth sectors as a three-section type modulation sector, and commanding that a reference vector Vref which generates the three-phase PWM wave is synthesized by two basic vectors in the above six sectors; defining second, third, sixth, seventh, tenth and eleventh sectors as a five-section type modulation sector, and commanding that the reference vector Vref which generates the three-phase PWM wave is synthesized by three basic vectors in the above six sectors. According to the invention, without increasing hardware cost, through controlling a pulse width generating mode, power device switching loss can be decreased by 50% based on a present SVPWM control method.

The invention relates to a road and bridge dotting device for municipal construction. The road and bridge dotting device includes a housing, a traveling wheel, a drive wheel, a transmission roller, a driven wheel, and a dotting device; the housing is of a hollow rectangular structure; a traveling hole is formed in a lower end surface of the housing; a dotting hole is formed in the lower end surface of the housing and positioned on the right side of the travelling hole; the travelling wheel includes a travelling wheel shaft, a travelling wheel body and a first gear; the drive wheel includes a drive wheel shaft, a drive wheel body, and a second gear; the transmission roller includes an inclined slide rail, a first clamping head, a primary threaded rod, a primary nut, a secondary nut, an a secondary threaded rod; the driven wheel includes a driven wheel shaft, a drive wheel body, and a stirring inserting rod; and the dotting device includes a dotting rotation shaft, a dotting horizontal rod, and a dotting probe. The dot distance-adjustable dotting device is easy to operate; the dotting device is pushed lightly so as to allow the travelling wheel to rotate, and a dotting operation is executed; the dotting distance can be adjusted by rotating the primary nut and the secondary nut.

The invention provides a model-based variable-preview-distance and speed-constrained path tracking method. In order to make path tracking have more characteristic of manned driving under the use of model control while meeting the tracking precision requirement of unmanned driving, the path tracking method provided by the invention comprises transverse steering control and longitudinal speed constraint. The transverse steering control is solved according to a control reference quantity generated by a changing preview distance, and the changing preview distance is calculated according to a current transverse error and the curvature of a preview point. The longitudinal velocity constraint is the maximum longitudinal velocity determined by the road curvature of the preview point at a specifiedmaximum lateral acceleration. The method can be applied to the tracking of complex paths, makes path tracking have more characteristic of manned driving while meeting the tracking precision, reducesthe action frequency of the actuator, and improves the riding comfort.

The invention discloses a tumor radiotherapy positioning device and belongs to the technical field of medical device auxiliary devices. The positioning device comprises a radiotherapy bed, a protection device and a positioning device. The radiotherapy bed comprises a first bed body and a second bed body. A headrest and two holding rods are arranged on the first bed body. The protection device comprises two protection plates, a radiotherapy window and two vertical plates. The protection plates are slidably connected with the radiotherapy window. The radiotherapy window is slidably connected with the two vertical plates and the radiotherapy bed. The positioning device comprises at least four positioning pots, an air extracting pump and a positing plate. The lower end of each positioning potis opened. A thread column and a nozzle are arranged on the upper top face of each positioning pot. A thread hole is arranged in the positioning plate. The positioning plate is in threaded connectionwith the thread columns. The air extracting pump is connected with the nozzle. A through hole with adjustable size is arranged in the positioning plate and is formed by multiple connected annular pieces. Adjacent annular pieces are in threaded connection with each other. According to the invention, the positioning device is accurate in positioning and damage to body of a patient is small.

The invention discloses an ammonia-process desulfurization optimum control method based on multi-variable constraint zone predicting control. The ammonia-process desulfurization optimum control methodhas the advantages that by adopting the multi-variable constraint zone predicting control method, the intake flow rate of ammonia water between the absorption section and oxidization section of a desulfurization tower can be well coordinated; at the premises of ensuring the desulfurization efficiency, the control quality of the system is improved, the running cost of the system is reduced, and the economic and environment-friendly running of the system is accelerated.

The invention belongs to the field of thermotechnical automatic control, and particularly discloses a power station SCR (selective catalytic reduction) ammonia spraying control method based on a denitration reaction kinetic equation. The method specifically comprises the following steps: equally dividing an SCR system to n reaction areas and building a model, determining an unknown parameter of the model, so as to obtain a practical reaction model, forecasting for p moments in future according to a working condition parameter at a current moment, and through optimizing a performance index, acquiring an optimal ammonia spraying quantity change rate, after executing an ammonia spraying quantity in the next moment, repeatedly performing the above steps, so as to realize rolling optimization.According to the method, through building the reaction model and optimizing the performance index, the on-line rolling optimization to an ammonia spraying flow is realized, thereby the problems of great inertia and uncertainty of the SCR system are solved, the precision, speed and stable capacity of SCR ammonia spraying control are improved, and the problems that NOx discharge exceeds a standard or ammonia escapes are effectively avoided, and the method is particularly suitable for a set with frequently fluctuant load.

The present invention discloses a social contact information display method, a social contact information display system and a server. The social contact information display method includes the following steps that: the sorting score of social contact information is calculated out according to a receiving time weight corresponding to the social contact information and a classification label weight corresponding to the information classification label of the social contact information; and the social contact information requested by a client is sent to the client, wherein the social contact information carries the sorting score, so that the client can sort and display the social contact information according to the sorting score of the received social contact information. According to the social contact information display method, the social contact information display system and the server of the invention, the sorting score of the social contact information is calculated out according to the receiving time weight and the classification label weight, and the social contact information is sorted and displayed by the client according to the sorting score, and therefore, a condition that the social contact information is sorted according to the issuing order of the social contact information can be avoided, and the action frequency of a user can be decreased, and user experience can be improved.

The invention relates to a multifunctional working hanging basket for a railway tunnel. The multifunctional working hanging basket comprises a rail flat car and further comprises a base, a rotation table, a lifting device, a hydraulic system, an electric control operation device, a main control oil cylinder, a working machine large arm, a working main arm, a secondary arm oil cylinder, a secondary arm, a working hanging basket body and a working arm oil cylinder. According to the multifunctional working hanging basket for the railway tunnel, the existing rail flat car is used as a carrier, the hanging basket body can retract in the transportation state and does not exceed the railway transportation limit, the hanging basket body can conduct work rapidly when reaching a working point position, the rotation table of the multifunctional working hanging basket enables the hanging basket body to rotate and move at will in the working area, the moving frequency of the flat car is reduced, meanwhile, the lifting device of the multifunctional working hanging basket can lift and move goods and materials in the working area, and therefore the labor intensity is relieved; the working efficiency and the construction safety are improved, cost is saved, and inspection and treatment construction of damage of the railway tunnel can be completed rapidly.

The invention discloses a working roll bending device of a plate band rolling mill. The device is fixedly arranged on a rolling mill stand, and roll bending devices are arranged on two end parts of an upper working roll and a lower working roll so as to carry out supporting, balancing and roll bending control on the upper working roll and the lower working roll to improve the convexity of a loaded roll gap between the upper working roll and the lower working roll and control the plate shape. The roll bending device comprises a memorial archway, upper roll bending devices and lower roll bending devices, wherein the memorial archway is a framework body, and upright posts at the left side and the right side of the memorial archway are respectively inwards and convexly provided with a waist bump; the upper roll bending devices can be slidably arranged in the memorial archway, positioned above the waist bump and assembled at two ends of the upper working roll; and the lower roll bending devices can be slidably arranged in the memorial archway, positioned below the upper roll bending device and assembled at two ends of the lower working roll. The working roll bending device of the plate band rolling mill can meet the working requirement of a large large-openness plate band rolling mill and has the advantages of reliable rolling quality and long service life.

The invention relates to the technical field of natural gas remote regulation and control, in particular to a device and method for remote regulation and control of petroleum and natural gas wellhead yield. The device comprises remote terminal equipment and a PLC control unit which is in communication with the the remote terminal equipment. The device is characterized by further comprising an electric actuating mechanism which is in electric connection with the PLC control unit, a throttle valve connected with the electric actuating mechanism and a data acquisition unit and a data processor which are arranged between the throttle valve and the PLC control unit; a fixing seat is arranged on the upper portion of the throttle valve, the electric actuating mechanism is fixedly connected to the upper end face of the fixing seat, a through hole is formed in the middle of the fixing seat in the vertical direction, a connecting shaft penetrates through the through hole, the upper portion of the connecting shaft is connected with the electric actuating mechanism, and the lower portion of the connecting shaft is connected with a valve rod of the throttle valve. By mean of the device and method for the remote regulation and control of the petroleum and natural gas wellhead yield, remote safe regulation and control of the natural gas yield of a well with high pressure and high production ratecan be achieved, and therefore gas well unattended operation can be achieved.

The invention provides a frequency control method for a multi-energy complement power supply system. The method comprises the following steps: controlling the power frequency partition of a photovoltaic grid inverter; controlling the power frequency partition of a mixed energy storing system; controlling the power frequency partition of a multi-energy complement power supply system. The frequency control method for the multi-energy complement power supply system, provided by the invention, can be applied to the multi-energy complement power supply system, and can realize the purpose that a generator unit and an electric and electronic electricity generation unit are rotated synchronously to jointly control the system frequency, so that the influence of high amplitude power fluctuation on the system frequency is effectively restrained, and the power supply quality of the system is improved.

The invention discloses an arc-shaped motion platform for insulator laser cleaning. The arc-shaped motion platform comprises an arc-shaped track, a first moving device, a second moving device, a mounting table and a first detection piece. The mounting table is mounted on the second moving device and is used for fixing a laser sweeper; the second moving device is mounted on the first moving device and used for driving the mounting table to move in the radial direction of the arc-shaped track; the first moving device is mounted on the arc-shaped track and used for driving the second moving device to move in the circumferential direction of the arc-shaped track; and the first detection piece is used for detecting the distance between the laser sweeper and the surface of the insulator to be swept. The cleaning range is expanded, the cleaning efficiency is improved, accurate movement adjustment of the mounting table in the radial direction of the arc-shaped track can be achieved, the distance between a laser head of the laser cleaner and the surface of the insulator to be cleaned can be conveniently adjusted, focusing is guaranteed to improve the cleaning effect, and the applicability is good.

The invention discloses a hovercraft slew rate maintaining control method adopting a guide module. The hovercraft slew rate maintaining control method comprises steps as follows: a slew rate control guide module reads a set slew rate and a current actual course angle, and a current expected course angle is obtained and transmitted to a comparator; the comparator compares the received expected course angle with the current actual course angle, and course deviation is obtained and transmitted to a controller; the controller obtains a rudder angle control command according to the received course deviation, the rudder angle control command is sent to an air rudder, and the air rudder executes the command until the set slew rate is met. With adoption of the method, a hovercraft can be automatically controlled to slew, and the control level and the navigation stability can be improved.

The invention discloses an alignment element vectorization operating method based on virtual driving, belonging to an image information extraction technology. The method comprises the following steps of: 1) taking an image to be vectorized as a roaming object to generate a two-dimensional or three-dimensional scene; creating a virtual rover, arranging the virtual rover on the image and setting a cruising route of the virtual rover; 2) encapsulating an automatic tracking module to bring the automatic tracking module into roaming operation software; interacting an operation system with the encapsulated automatic tracking module; 3) cruising by the virtual rover along the cruising route, verifying the cruising route; when the cruising route is missed, or the virtual rover is arranged at the terminal of the cruising route, or manual direction adjusting information is produced in an automatic cruising process, switching the virtual rover into a manual driving state to generate or edit the cruising route; and 4) respectively carrying out statistics on path lengths of the virtual rover in the automatic cruising state and the manual driving state, and verifying accuracy of the cruising route. The method disclosed by the invention improves operating efficiency and has strong adaptability.

The invention discloses a powder material metering and conveying device of a mixing plant and a control method of the powder material metering and conveying device. The powder material metering and conveying device of the mixing plant comprises a material storage bin, a screw conveyer, a feed regulating valve, a metering hopper and a control part, wherein the screw conveyer is provided with a material inlet and a material outlet and the material inlet is connected with the material storage bin; the feed regulating valve is provided with an input end and an output end and the input end is connected with the material outlet; the metering hopper is connected with the output end; and the control part is connected with the feed regulating valve and the metering hopper and is used for receiving the metering signal of the metering hopper and controlling the feed regulating valve to adjust feed caliber. The powder material metering and conveying device of the mixing plant and the control method of the powder material metering and conveying device have the advantages that the powder materials can be rapidly conveyed, the working efficiency is high and the metering accuracy is high.

The invention provides a group dialog box sorting method and a terminal. The method comprises the steps of obtaining a friendly degree weight and a communication time weight of each group dialog box, wherein the friendly degree weight indicates the weight of number proportion that group members and local members are mutual friends in each group dialog box; and sorting the group dialog boxes based on the friendly degree weight and the communication time weight of each group dialog box, and generating a chat list according to a sorting result. According to the technical scheme of the group dialog box sorting method and the terminal provided by the invention, the action frequency of the user can be reduced, and the user experience is improved.

The invention provides an optical signal acquisition method used for visual endoscope devices; in the method, a reflecting device is arranged in the front end area of lens, which is used for reflecting the optical signals in the observed area and the reflected light of the reflector surface is applied so the operation is simple and the collected image is sharp; the invention also provides a visual endoscope device which comprises a top module and an installed reflecting device and a pair of automatically focusing mechanisms and image processing device. Through the installation of the reflecting device in a hemispherical nose module, the range and the strength of exposure of the light source and the field of view of the lens are enlarged and the travel frequency of the top module is reduced; the automatically focusing mechanism can be used for automatically adjusting the relative position of the lens to the reflecting device so as to obtain the sharp images; the image processing devicecan be used for processing image signals collected by CMOS module and reflected by the reflecting device so that the image can truly reflect the size and shape of real objects; the device has a reasonable structure, which can be used for pedestrian flow, the detection of intestines and stomach etc.

The invention relates to a sodium hypochlorite preparation system capable of being controlled and debugged remotely based on an ARM single chip microcomputer and a working method thereof. The sodium hypochlorite preparation system comprises an ARM single chip microcomputer, a first drive circuit, a second drive circuit, an analog signal processing circuit, an electrolysis power supply, a concentrated salt pump, a softened water regulating valve, a softened water flow module, an operation indication module, an electrical conductivity meter, an alarm indication module, a 4G module, an HMI moduleand a wireless data transmission module. The sodium hypochlorite preparation system has a remote diagnosing and debugging function. Warning and alarm can be issued for the key parameters of system operation, so that users can find safety risks early to avoid loss caused by system device aging. Users can be remotely notified of corresponding alarm and handle the alarm, and the parameters of fieldoperation can also be modified and optimized remotely. By using the Internet-of-things technology, manufacturers and users can have a real-time understanding of the field operation situation and dealwith an abnormal situation in time.