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57results about How to "Simple control technology" patented technology

Method for multi-frequency hybrid calibration of vibration measuring sensor

A method for multi-frequency hybrid calibration of a vibration measuring sensor comprises the following steps that a standard sensor and a measured sensor are fixed on a vibration table, and the axial direction of the two sensors is consistent with the main vibration direction of the vibration table; a signal producing module generates multi-frequency signals; the multi-frequency signals pass through a power amplifier and drive the vibration table; output signals of the standard sensor and the corrected sensor are collected, and the output signal of the standard sensor is converted to obtain an amplitude spectrum of the vibration table; the output signal of the corrected sensor is converted to obtain a corresponding amplitude spectrum; the amplitude spectrum of the vibration table is divided by the amplitude spectrum of the corrected sensor, and the obtained set of quotients is the sensitivity of the corrected sensor at frequency points synthesizing the multi-frequency signals. The method has the advantage of being capable of achieving rapid and accurate calibration of the vibration measuring sensor.
Owner:ZHEJIANG UNIV

Comprehensive method for vector or direct torque control of doubly-fed wind generator

The invention relates to a comprehensive method for vector or direct torque control of a doubly-fed wind generator and belongs to a comprehensive method which uses the vector control when the doubly-fed wind generator is in a stable operation state and uses the direct torque control when the doubly-fed wind generator is in a wind power generating transient state. The comprehensive method mainly solves the technical problems existing in the prior wind generator control method that the transient swing is hard to control due to the sudden change of wind force. The technical proposal comprises the following steps: a) establishing a conventional vector control mathematical model of the doubly-fed wind generator in the stable operation state, due to the control of component voltage and current on the d and q axes by pulse width modulation(PWM), controlling the AC exciting current frequency of the wind generator by a grid electrode of a bipolar triode switch of a corresponding isolated gate in an adjusting converter, and realizing the super-synchronous and sub-synchronous variable speed constant frequency power generation of the wind generator; and b) in the wind power generating transient process, using the doubly-fed wind generator controlled by the method of the direct torque control of the wind generator.
Owner:山西合创电力科技有限公司

Method for producing bio-coal

The invention discloses a preparation method of biomass coal, which equably mixes the mud of sewage treatment factory, paper mill and alcohol plant and biomass powder, such as active carbon, charcoal or coal in proportion with 10:0.5 to 2:0.5 to 2 and ferments for 3 to 5 days in heap mode. The preparation method of biomass coal can be eventually obtained after molding and insolation or drying, the heat of which can reach 4000 kilocalorie. The preparation method of biomass coal can be easy to learn the control technique, can not only resolve the mud treatment of sewage treatment plants but also make full use of waste biomass. The biomass coal provides flammable renewable sources and also has the advantages of simple production technique, good environmental protection performance, good energy-saving performance, high social benefit, low cost and high economic benefit.
Owner:丁恩德

Comprehensive method for vector or direct torque control of permanent magnetism type wind generator

The invention relates to a comprehensive method for vector or direct torque control of a permanent magnetism type wind generator, and belongs to a comprehensive method which uses the vector control when the permanent magnetism type wind generator is at a stable operation state and uses the direct torque control when the permanent magnetism type wind generator is in a wind power generating transient state. The comprehensive method mainly solves the technical problems existing in the prior wind generator vector method that the transient swing is hard to control due to the sudden change of wind force. The technical proposal comprises the following steps: a) establishing a vector control mathematical model of the permanent magnetism type wind generator in the stable operation state, due to the control of component voltage and current on the d and q axes by pulse width modulation(PWM), controlling the AC exciting current frequency of the permanent magnetism type wind generator by a grid electrode of a bipolar triode switch of a corresponding isolated gate in an adjusting converter, and realizing the control of the permanent magnetism type wind generator in a stable wind state; and b) in the wind power generating transient process, using the permanent magnetism type wind generator controlled by the method of the direct torque control of the permanent magnetism type wind generator(WGDTC).
Owner:山西合创电力科技有限公司

Excitation control method of doubly-fed wind-driven generator

InactiveCN102522942ALow control sensitivityActive power decoupling controlElectronic commutation motor controlVector control systemsWind drivenTime delays
The invention relates to an excitation control method of a doubly-fed wind-driven generator. The doubly-fed wind-driven generator has a doubly-fed motor. The motor includes: a stator, which supplies power for a power grid having a voltage with a rated value; and a driving rotor, which is coupled with the stator. One end of the rotor is connected with a wind turbine by a change-speed gear. A rotor winding is a three-phase wound rotor winding. The power grid supplies power for the rotor by a current transformer; and a stator voltage and a stator linkage are deposed on an xsynchronization rotation dq coordinate axis; therefore, it can be realized that power output by the generator stator is controlled by adjusting the rotor current. According to the method provided in the invention, there is no need to carry out complex conversion and calculation like vector rotation changing and the like; active and reactive decoupling control can be realized; a current control module has low control sensitivity; a circuit parameter and measurement time delay of a current transformer system has a little influence on current control; and the control technology is simple and thus cost of the controller is reduced.
Owner:CHINA AGRI UNIV

Control method of reactive power of doubly fed wind power generator

The invention relates to a control method of reactive power of a doubly fed wind power generator. The doubly fed wind power generator comprises a doubly fed motor, wherein the motor comprises a stator and a driving rotor, and the stator supplies power to a grid; the grid has rated voltage, and the driving rotor is coupled with the stator; one end of the rotor is connected to a wind turbine through a transmission gear, and a rotor winding is a three-phase wound rotor winding; and the grid supplies power to the rotor through a converter, and stator voltage and stator flux are decomposed onto a synchronously rotary dq coordinate axis to control the reactive power output by the generator stator by adjusting the current of the rotor. In the method, no complex transformation and calculation of vector rotation change and the like are needed, the control sensitivity of a current control module is lower, the circuit parameters and the measurement delay of a converter system have smaller impacton current control, and the control technology is simple, and thereby the cost of a controller is also reduced. The control method is suitable for application of a low-power wind power generator.
Owner:CHINA AGRI UNIV

Process and device for manufacturing printed products composed of a block of sheets and a cover

The method involves supplying a block of sheets (2) and covers (3, 3`, 3``) on a separate path by a processing device (4). The covers are connected with the block of sheets in a rear area in the processing device. The covers are fed to a storage (S) that includes a set of blowers on the path for the processing device, where the covers are fed to the blowers. The covers are identified by an identification device (18). The blowers are moved between an inlet transport device and an outlet transport device, and are tilted around an axis. An independent claim is also included for a device for executing a method of manufacturing printed products composed of a block of sheets and a cover.
Owner:MULLER MARTINI HLDG

Flight device control system and control method

The invention provides a flight device control system, which comprises a first instruction input system and a second instruction input system. The first instruction input system comprises a camera subsystem and an image processing subsystem. The camera subsystem is arranged on a flight device main body and is used for obtaining image and / or video information; the image processing subsystem is used for processing the image and / or video information to obtain position information of one or more main bodies in images and / or videos; and the image processing subsystem is connected with an instruction processing unit and is used for transmitting the position information, serving as an instruction, to the instruction processing unit. The flight device control system and control method combine two control modes, thereby simplifying control technique of a flight device, enhancing system shooting stability, and meanwhile, preventing the defect that an existing full-automatic following control mode is monotonous and unattractive, providing more interest for flight shooting and meeting special functions, such as self-shooting of an operator.
Owner:成都第二记忆科技有限公司

Mobile robot chassis and mobile robot

The invention relates to a mobile robot chassis and a mobile robot. The mobile robot chassis comprises a chassis frame provided with a rotating frame, a first driving device arranged on the rotating frame and a traveling mechanism connected with the driving device and driven to move by the driving device. The traveling mechanism comprises a first driving wheel, a second driving wheel and a drivenwheel, wherein the first driving wheel and the second driving wheel are differential wheels, and the driven wheel is a universal wheel; the first driving wheel and the second driving wheel are arranged on opposite sides of the lower end of the rotary frame, and the driven wheel is arranged on the bottom of the chassis frame. The chassis of the mobile robot of the invention adopts the differentialwheels as the driving wheels and the universal wheel as the driven wheel, thus the manufacturing cost is low and the control technology is simple; at the same time, the origin locking mechanism is designed. When the origin locking mechanism locks the rotating frame, the mobile robot chassis becomes the differential chassis. When the lock is unlocked, the mobile robot chassis becomes the omni-directional moving chassis, which realizes the switching of different motion modes and has higher flexibility.
Owner:SHENZHEN UROVO TECH CO LTD

Indicating method and system for scanning area

The invention discloses an indicating method and system for a scanning area. The method comprises steps as follows: according to a predetermined scanning mode of a current patient, the scanning area corresponding to the patient is estimated, and a table board position corresponding to the scanning area is determined; the scanning area comprises a scanning starting position; according to the correspondence between the table board position and LED indicating lamps arranged on at least one side of a table board, the LED indicating lamps corresponding to the scanning area are controlled to be lit in the set manner; an indicating interval of the lit LED indicating lamps is used for indicating the position, located on the table board, of a to-be-scanned part of the current patient; when the position, located on the table board, of the to-be-scanned part of the current patient is determined to be consistent with the indicating interval of the lit LED indicating lamps, the table board position, corresponding to the scanning starting position, of the table board of a examining table is controlled to move to an exposure starting position of a CT (computed tomography) machine. According to the technical scheme, the use efficiency of the CT machine can be improved.
Owner:SIEMENS SHANGHAI MEDICAL EQUIP LTD

Wind driven engine with combined wind cups and blades

The present invention discloses one kind of wind driven engine with combined wind cups and blades, and aims at improving the operation mode of wind driven engine. The wind driven engine has one main shaft with one or several sections, and one set of arms mounted on the main shaft and with at least one wind cup-blade capable of changing upwind angle each. The wind driven engine may be driven with wind in any direction and has high efficiency, simple structure and easy control. The present invention may be used in various kinds of energy converter.
Owner:王跃

Seabed underwater vehicle

The invention discloses a seabed underwater vehicle. The seabed underwater vehicle comprises a mother underwater vehicle and multiple sub underwater vehicles; the mother underwater vehicle comprises apropulsion system, a course control system, a weapon release system, multiple sub underwater vehicle storage, charging and repairing units, a mother body master control system, a sonar transmitting,receiving and processing system, a mother body gas storage chamber, a nuclear power conversion system and a motor power system; the multiple sub underwater vehicle storage, charging and repairing units cover the whole body of the mother underwater vehicle to be fixedly connected with the mother underwater vehicle; and each sub underwater vehicle storage, charging and repairing unit comprises a subunderwater vehicle. The seabed underwater vehicle can very well replace human beings to execute a series of military missions in the deep sea field; the seabed underwater vehicle can be divided intomultiple small-sized underwater vehicles to realize omnibearing three-dimensional reconnaissance; multiple functions such as intelligence reconnaissance, information transmission and attacking enemy forces are also realized; and activities such as territorial sea cruising, deep sea reconnaissance and deep sea scientific research can be finished.
Owner:NANJING UNIV OF SCI & TECH

Method for controlling active power of double-fed wind power generator

The invention discloses a method for controlling the active power of a double-fed wind power generator. The double-fed wind power generator has a double-fed motor, wherein the double-fed motor has a stator and a driving rotor; the stator supplies power to a power grid; the power grid has a voltage with a rated value; the driving rotor is coupled with the stator; one end of the driving rotor is connected to a wind turbine through a speed-changing gear; rotor windings are three-phase coiling type rotor windings; the power grid supplies power to the driving rotor through a converter; and by decomposing a stator voltage and a rotor flux linkage on a synchronously rotary dq coordinate axis, the active power which is output by the stator of the generator can be controlled by regulating a rotor current. The method has the advantages that: the complicated conversion and calculation of vector rotation change and the like are not required; a current control module is relatively lower in controlsensitivity; current control is less influenced by circuit parameters of a converter system and measurement delay; a control technology is simple; the cost of a controller is reduced; and the method is applicable to a low-power wind power generator.
Owner:CHINA AGRI UNIV

Aircraft emergency control device and control method thereof

The invention discloses an aircraft emergency control device and a control method. The aircraft emergency control device includes a communication signal receiving and feedback module (1) and an aircraft control system processor (2); the communication signal receiving and feedback module (1) receives instruction signals sent by a ground base station or instruction signals sent by a satellite, and transmits the received signals to the aircraft control system processor (2); the aircraft control processor system comprises a microprocessor module (3) and an emergency control module (4); and the output end of the microprocessor module (3) is connected with the input end of the emergency control module (4), so that an aircraft can enter a preset emergency flight mode. According to the aircraft emergency control device and the control method of the invention, the communication signal receiving and feedback module is just additionally adopted, and the combinations of various kinds of communication signals or key combinations which are simple in logic are adopted in cooperation, and therefore, flight control can be performed on the aircraft losing remote control signals, and the crash of the aircraft due to being out of control can be avoided.
Owner:至简天蕴智控科技(苏州)有限公司

Integrated method of vector and direct torque control of induction wind generator

The invention relates to an integrated method of vector and direct torque control of an induction wind generator, which belongs to the integrated method of using vector control under the stable operation state of the induction wind generator and adopting direct torque control during the transient process of wind power generation. The integrated method is mainly used for solving the technical difficult problem that the transient process of the existing wind generator set which shows sudden unstable operation due to the change of wind power is difficult to control. The technical scheme of the invention is as follows: the integrated method of the vector and direct torque control of the induction wind generator comprises the following steps: a controller on the side of the induction wind generator detects the rotational speed of a rotor and a wheel paddle fan of the induction wind generator through a rotational speed measuring device in a real time manner, if the rotational speed measuringdevice measures that the induction wind generator is in the stable operation state, the vector control method is adopted for controlling the operation of the induction wind generator, if the rotational speed measuring device measures that the induction wind generator is in the transient operation state, the direct torque control method is adopted for controlling the operation of the induction wind generator.
Owner:山西合创电力科技有限公司

Adaptive internal model vibration control method for intelligent fan blades based on gray information optimization

The invention discloses an adaptive internal model vibration control method based on gray information optimization for intelligent fan blades. The method aims at various uncertain factors existing in the vibration system of intelligent fan blades in a complex operating environment, and adopts a method based on gray information theory optimization. The self-adaptive internal model vibration control method uses the differential evolution identification method of gray relational optimization to accurately identify the blade vibration system under the influence of uncertainty, making the identification of the internal model vibration process more ideal and accurate; The parameters of the modal vibration controller are adaptively optimized and adjusted, which is conducive to improving the dynamic characteristics and robustness of the control system, so that the closed-loop system can achieve high-performance adaptive vibration control of intelligent fan blades while overcoming the influence of uncertain factors. Through the present invention, the gray optimization self-adaptive internal model vibration control method provided can overcome the influence of multiple uncertain factors of intelligent fan blades in a complex working environment.
Owner:YANGZHOU UNIV

Actuating unit for a constant mesh transmission and constant mesh transmission comprising such an actuating unit

InactiveCN101910686APeriodic uniform decreaseShort maintenance periodGearing controlNeutral positionVariator
The invention relates to an actuating unit for a constant mesh transmission, particularly of a motor vehicle, comprising a selector fork that can be axially displaced at least between a first position associated with a first gear step of the constant mesh transmission and a neutral position. A positioning shaft is provided, on which two positioning elements for the selector fork are supported axially displaceably, but non-rotatably. The positioning elements comprise each a contact section for the temporary contact with the selector fork. The positioning shaft can be rotated together with the positioning elements for setting predetermined different angular positions of the positioning elements. Each positioning element is associated with an actuating element, by which the positioning element can be displaced as a function of the set angular position thereof axially along the positioning shaft. Furthermore, the invention relates to a constant mesh transmission comprising such an actuating device.
Owner:MAGNA POWERTRAIN AG & CO KG

Method for regulating rhopilema esculentum kishinouye scyphistoma multi-crop strobilation

The invention discloses a method for regulating rhopilema esculentum kishinouye scyphistoma multi-crop strobilation, and belongs to the technical field of aquatic animal breeding. By controlling the water temperature at 15-19 DEG C and the feed amount, rhopilema esculentum kishinouye scyphistoma is subjected to repeated strobilation so that the total number of ephyrae released by the same amount of scyphistoma is increased by 2-5 times. The method can effectively increase the utilization rate of rhopilema esculentum kishinouye scyphistoma fry, that is, the number of the rhopilema esculentum kishinouye scyphistoma fry can be increased in a short period, the problem that the fry are out of season in a multi-crop breeding mode and accordingly the fry are insufficient in supply is also solved,the production cost is reduced, rhopilema esculentum kishinouye fry breeding efficiency and economic benefits of rhopilema esculentum kishinouye breeding are greatly improved, the control technologyis simple, and the method is suitable for wide popularization.
Owner:LIAONING OCEAN & FISHERIES SCI RES INST

Comprehensive method for vector and direct torque control on doubly-fed wind generator

The invention relates to a comprehensive method for vector and direct torque control on a doubly-fed wind generator, and belongs to a comprehensive method which uses vector control when the doubly-fed wind generator is in a stable operation state and uses direct torque control when the doubly-fed wind generator is in a wind power generation transient state. The invention mainly aims to solve the technical problem existing in the prior wind generator control method that the transient swing is hard to control due to the sudden change of wind force. According to the technical scheme, the method comprises the following steps: a) establishing a conventional vector control mathematical model of the doubly-fed wind generator in the stable operation state, and adjusting the gate of a corresponding insulated gate bipolar triode switch in a converter through control on component voltage and current of the d and q axes by pulse width modulation (PWM) so as to control the AC exciting current frequency of the wind generator and to further realize super-synchronous and sub-synchronous variable-speed constant-frequency power generation of the wind generator; and b) controlling the doubly-fed wind generator by a wind generator direct torque control method in the wind power generation transient state. The drawing shows the principle control diagram of the invention.
Owner:上海迅微信息科技有限公司

High-rigidity two-plate die locking mechanism

The invention relates to a high-rigidity two-plate die locking mechanism which comprises a fixed die plate, a moving die plate and four pull rods, wherein after correspondingly penetrating through four through holes I formed in four corners of the fixed die plate, the fixed ends of the four pull rods are spirally connected with four pull rod nuts correspondingly, and then connected onto the fixeddie plate; after correspondingly penetrating through four through holes II formed in four corners of the moving die plate, the moving ends of the four pull rods are fixedly connected onto four brake mechanisms arranged on the outer side of the moving die plate correspondingly, and then the moving die plate is connected to the fixed die plate along the reciprocating motion of the four pull rods relative to the fixed die plate; the four pull rod nuts are all connected to one and the same driving mechanism through one and the same transmission mechanism; and under the drive of the driving mechanism, the positions of the four pull rods on the fixed die plate are synchronously adjusted. According to the high-rigidity two-plate die locking mechanism provided by the invention, the brake positiondifference which needs to be compensated for due to the different die thicknesses can be automatically compensated for by slightly adjusting the relative position between the four pull rods and the fixed die plate, and then the influence of the compressibility of hydraulic oil on the rigidity of the high-rigidity two-plate die locking mechanism can be reduced to the minimum.
Owner:欧任伍

Integrated method of vector and direct torque control for doubly-fed wind turbines

The invention relates to a comprehensive method for vector or direct torque control of a doubly-fed wind generator and belongs to a comprehensive method which uses the vector control when the doubly-fed wind generator is in a stable operation state and uses the direct torque control when the doubly-fed wind generator is in a wind power generating transient state. The comprehensive method mainly solves the technical problems existing in the prior wind generator control method that the transient swing is hard to control due to the sudden change of wind force. The technical proposal comprises the following steps: a) establishing a conventional vector control mathematical model of the doubly-fed wind generator in the stable operation state, due to the control of component voltage and current on the d and q axes by pulse width modulation(PWM), controlling the AC exciting current frequency of the wind generator by a grid electrode of a bipolar triode switch of a corresponding isolated gate in an adjusting converter, and realizing the super-synchronous and sub-synchronous variable speed constant frequency power generation of the wind generator; and b) in the wind power generating transient process, using the doubly-fed wind generator controlled by the method of the direct torque control of the wind generator.
Owner:山西合创电力科技有限公司

Temperature control method of hydrogen catalysis combustor

The invention relates to a temperature control method of a hydrogen catalysis combustor, and belongs to the technical field of hydrogen catalysis combustion. The control process of the temperature control method of the hydrogen catalysis combustor includes the steps that firstly, a data processor collects the outlet temperature of the hydrogen catalysis combustor through a temperature sensor; secondly, the data processor records the temperature change of the hydrogen catalysis combustor and compares the temperature change with a set value; and thirdly, the data processor conducts carries out feedback regulation on the fuel-air ratio of hydrogen and air according to the comparison result of the temperature of the catalysis combustor and the set value. The temperature control method has the beneficial effects of being simple in control technology, convenient to use, stable, reliable, economical, affordable, low in cost, wide in application range and the like, and can be widely used for temperature control of the hydrogen catalysis combustor.
Owner:CHINA JILIANG UNIV

Comprehensive method for vector and direct torque control of permanent-magnetic wind generator

The invention relates to a comprehensive method for vector and direct torque control of a permanent-magnetic wind generator, and belongs to a comprehensive method which uses vector control when the permanent-magnetic wind generator is in a stable operation state and uses direct torque control when the permanent-magnetic wind generator is in a wind power generation transient state. The invention mainly aims to solve the technical problem existing in the prior wind generator control method that the transient swing is hard to control due to the sudden change of wind force. According to the technical scheme, the method comprises the following steps: a) establishing a vector control mathematical model of a permanent-magnetic wind generator in the stable operation state, and adjusting the gate of a corresponding insulated gate bipolar triode switch in a converter through control on component voltage and current of the d and q axes by pulse width modulation (PWM) so as to control the AC exciting current frequency of the permanent-magnetic wind generator and to further realize the control on the permanent-magnetic wind generator in a stable wind state; and b) controlling the permanent-magnetic wind generator by a wind generator direct torque control (WGDTC) method in the wind power generation transient state. The drawing shows the principle control diagram of the invention.
Owner:上海迅微信息科技有限公司

Comprehensive method for vector or direct torque control of permanent magnetism type wind generator

The present invention relates to a comprehensive method for vector or direct torque control of a permanent magnetism type wind generator, and belongs to a comprehensive method which uses the vector control when the permanent magnetism type wind generator is at a stable operation state and uses the direct torque control when the permanent magnetism type wind generator is in a wind power generating transient state. The comprehensive method mainly solves the technical problems existing in the prior wind generator vector method that the transient swing is hard to control due to the sudden change of wind force. The technical proposal comprises the following steps: a) establishing a vector control mathematical model of the permanent magnetism type wind generator in the stable operation state, due to the control of component voltage and current on the d and q axes by pulse width modulation (PWM), controlling the AC exciting current frequency of the permanent magnetism type wind generator by a grid electrode of a bipolar triode switch of a corresponding isolated gate in an adjusting converter, and realizing the control of the permanent magnetism type wind generator in a stable wind state; and b) in the wind power generating transient process, using the permanent magnetism type wind generator controlled by the method of the direct torque control of the permanent magnetism type wind generator (WGDTC).
Owner:山西合创电力科技有限公司

Front-rotating rear-driving robot chassis and moving robot

The invention discloses a front-rotating rear-driving robot chassis and a moving robot, belongs to the technical field of mobile robots, and aims to solve the technical problem of how to widely apply the robot to complex road condition environments such as outdoor roads and parks. The robot chassis comprises a front-drive steering system and a rear-drive system, wherein the front-drive steering system and the rear-drive system are connected with wheels to achieve movement and steering of the robot chassis; a suspension system, wherein the front-drive steering system and the rear-drive system are respectively connected with the suspension system, and are used for bearing the load of the robot and absorbing shock, so that tires can uniformly touch the ground when the robot passes through a bumpy road surface; a frame system, which is in supporting connection with the front-drive steering system, the rear-drive steering system and the suspension system and bears a chassis load and an external load; and a wheel system, which is used for bearing a chassis load and an external load, realizing steering of the robot according to action requirements of the front-drive steering system and driving the robot to run according to control of the rear-drive system.
Owner:山东新一代信息产业技术研究院有限公司

Deployment or utility vehicle for limited access area of operation

An application or utility vehicle for a spatially limited area of use comprises at least one electric motor (26) for driving the vehicle, at least one accumulator (30) for providing electrical energyfor the electric motor (26) and at least one internal combustion engine (32), in particular a diesel engine for driving at least one working machine (34) associated with the utility or commercial vehicle. The internal combustion engine (32) is also set up to charge the accumulator (30).
Owner:FRAPORT AG
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