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47results about How to "Increase control frequency" patented technology

A balanced control method for full bridge MMC capacitor voltages

The invention discloses a balanced control method for full bridge MMC capacitor voltages. The method comprises the following steps: (1) a positive input record database, a negative input record database and an abscission record database are established; (2) a sub-module with a maximum capacitor voltage and a minimum capacitor voltage in the record databases and on bridges arms are found out; (3) according to information such as bridge arm levels, bridge arm currents and the capacitor voltages, sub-modules which need to be subjected to switching are selected through logic judgment; and (4) corresponding switching operation is carried out on the selected sub-modules, and data updating is carried out on the record database. According to the invention, under a condition that the capacitor voltages are maintained to be stable, the switching frequency of the sub-modules can be effectively reduced; losses of a transverter can be reduced; and simultaneously, decrease in the system control frequency and system operation performance deterioration, etc., due to ordering problems are avoided.
Owner:ZHEJIANG UNIV

Driving control circuit used for laser tracker precision servo system

The invention provides a driving control circuit used for a laser tracker precision servo system. The driving control circuit comprises a data collection board used for collecting data of a permanent magnetic synchronous motor, a main control board connected with an upper computer and the data collection board and used for acquiring a target state command and reference input signals from the upper computer, acquiring data of the permanent magnetic synchronous motor from the data collection board and processing the target state command, the reference input signals and the data of the permanent magnetic synchronous motor to generate a control signal and a power driving board connected with the main control board and used for conducting power amplifying on the control signal output by the main control board and outputting a control voltage signal to drive the permanent magnetic synchronous motor to work. The circuit is formed by combining three circuit boards of the main control board, the data collection board and the power driving board in terms of hardware, configuration can be conducted according to the specific application requirements, and the flexibility is higher.
Owner:ACAD OF OPTO ELECTRONICS CHINESE ACAD OF SCI

Head positioning method, and disk apparatus using the same

A first estimator 13 estimates the position of a head based on a VCM driving signal u1 and a voltage signal Va output from a VCM 6 to output a first head position estimation signal x1est. The first estimator 13 estimates the disturbance acting on a head supporting mechanism 8 to output a disturbance estimation signal τdest. A second estimator 15 estimates the displacement of the head based on a control signal c2 for a fine adjustment actuator 7 to output a displacement estimation signal x2est. The first head position estimation signal x1est and the displacement estimation signal x2est are added together to obtain a second head position estimation signal xest. A position error signal e is generated using a head position signal x obtained by detecting the servo information and the second head position estimation signal xest. A disturbance compensator 10 synthesizes a VCM control signal c1 with the disturbance estimation signal τdest to generate the VCM driving signal u1.
Owner:PANASONIC CORP

Control system for satellite antenna motion

A satellite antenna kinetic control system comprises a system setting circuit, a main control unit, a drive and power circuit, a current sensing circuit, a angular position sensing circuit, a rotate speed sensing circuit and a actuator. The main control unit mainly includes a DSP chip and a FPGA chip. The utility model effectively improves the pointing accuracy and the dynamic tracking performance and decreases the cubic capacity and the power consumption of the control system, so as to provide the significant value for the application in the field of the satellite antenna pointing control system.
Owner:BEIHANG UNIV

Low switching frequency model prediction power control algorithm of single-phase pulse rectifier

The invention discloses a low switching frequency model prediction power control algorithm of a single-phase pulse rectifier. Under the low switching frequency, power prediction values of active power and reactive power are calculated through a model prediction power algorithm; then the component of the minimal optimal control quantity of an evaluation function is calculated under a rotating coordinating system; regulating waves subjected to volt-second compensation is acquired through the volt-second balancing compensation algorithm; and finally an on-off control signal is generated by combining a pulse width modulating strategy, and the control of the single-phase pulse rectifier is finished. According to the invention, the control precision of the low switching frequency model prediction power control algorithm of the single-phase pulse rectifier is improved with no need to repeatedly calculate the evaluation function, so the complexity of the algorithm is reduced; control and sampling efficiency is improved; the algorithm has good dynamic and stable-state performance, and high in flexibility; and different modulating strategies and control can be adopted to cooperate with the control algorithm so that requirements in different application occasions are met.
Owner:SOUTHWEST JIAOTONG UNIV

Control method and control system of foldable arm rest and engineering machinery

The invention discloses a control method of a foldable arm rest. The control method includes a detection step: detecting whether each arm section is in a completely closed state or not, a calculation step: ensuring that the arm section is in a completely folding state when the arm section is not in a completely closed state, obtaining the folding state of each arm section, working out the maximum distance L between the arm rest portion which is between the predetermined arm section and the tail end of the folding arm rest and a hinge point of the root end of the predetermined arm section according to the folding state of each arm section, and working out the allowable maximum angular velocity w when the predetermined arm section moves according to a predetermined linear velocity V and the maximum distance L, and a control step: controlling an actuating part which drives the predetermined arm section, and enabling the predetermined arm section to move at an angular velocity which is less than or equal to the maximum angular velocity w. The invention correspondingly discloses a control system of the foldable arm rest and engineering machinery. The control method and the control system has the advantages of being capable of improving folding speed of the foldable arm rest and working efficiency, easy to control, low in cost and good in stability.
Owner:ZOOMLION HEAVY IND CO LTD

Doubly-fed wind generator rotor linkage constant-frequency model prediction control method

The invention discloses a doubly-fed wind generator rotor linkage constant-frequency model prediction control method. According to the method, a three-voltage-vector selection method is selected based on the determination of the rotor linkage variation, a voltage vector selection mode requires that two effective vectors and a zero vector adjacent to the sector where a rotor voltage vector is are selected during each switching period, the rotor linkage follows a given value and optimizes the given value in real time to make the given value synchronous with the actual value of the stator linkage, and in order to weaken the fault impact of the stator linkage to the rotor linkage, the acting time of the selected effective vectors and the zero vector is determined based on a value function minimizing principle, and the switching state signals are obtained through the adoption of modulation technology. The method controls the converter by taking the rotor linkage error as the minimum during the switching period, and realizes the rapid tracking control of the rotor linkage. The switching frequency is constant, higher sampling frequency is not needed, control precision is high, and the rotor current can be effectively controlled within the allowed maximum current.
Owner:HENAN NORMAL UNIV

Communication control circuit for laser tracker

ActiveCN104898466AVarious forms of communicationEnhanced operational status monitoringProgramme control in sequence/logic controllersDecompositionTroubleshooting
The invention discloses a communication control circuit for a laser tracker, which comprises a digital signal processor, an acquisition module, a communication module, and a signal driving module. The control part of the digital signal processor of the communication control circuit only shoulders closed-loop control of the outermost layer position, and speed control and current closed-loop control are realized by the communication module in outer servo driving. In addition, the communication control circuit of the invention also adopts a modular design, and a testability design and an extensibility design are introduced. The circuit of the invention has complete integrated functions, the control part only shoulders closed-loop control of the outermost layer position, computational burden and real-time performance are reduced after decomposition, and hardware foundation is laid for adopting advanced control algorithm and improving the control frequency; monitoring on operation states of each module and the overall body is enhanced, and the debugging efficiency and the troubleshooting efficiency are improved; and the servo system which does not have a high real-time performance requirement can be directly used a current, speed and position three-closed loop integrated control and communication unit.
Owner:INST OF MICROELECTRONICS CHINESE ACAD OF SCI

Plasma synthetic jet actuator with low Reynolds number

The invention discloses a plasma synthetic jet actuator with low Reynolds number. The plasma synthetic jet actuator comprises an actuator discharge cavity (4), an actuator buffer cavity (2), a cathodedischarge electrode (6), an anode discharge electrode (5) and heat-resistant silica gel. The actuator discharge cavity (4) is placed inside the actuator buffer cavity (2), and the heat-resistant silica gel is used for fixing and sealing the cathode discharge electrode (6) and the anode discharge electrode (5) at the bottom of the actuator discharge cavity (4). Under the effect of the discharge electrodes, gas inside the actuator discharge cavity (4) becomes high-speed gas, the high-speed gas is ejected into the actuator buffer cavity (2) through high-speed jet holes (3), the high-speed gas becomes low-speed gas through speed reduction, the low-speed gas is ejected to the outside through low-speed jet holes (1), and finally low-speed gas with the Re of no more than 10<-6> are ejected inside the actuator buffer cavity (2). The plasma synthetic jet actuator is simple in structure, high in stability, high in efficiency and small in volume.
Owner:HARBIN INST OF TECH

Doubly-fed wind generator fault ride-through model prediction control method

The invention discloses a doubly-fed wind generator fault ride-through model prediction control method. When power grid voltage drops, by means of a rotor linkage prediction control method, an optimal voltage vector is selected by predicting the rotor linkage to be acted on a rotor side converter, so that the synchronous control of the rotor linkage and the stator linkage is realized, the fault impact of the stator linkage to the rotor linkage is weakened, and the rotor fault overcurrent is reduced. Compared with the model prediction control in the stable state, the control frequency through the adoption of the rotor linkage control method is increased by one time when the power grid has faults, the fault response speed is fast, the rotor current is effectively controlled within 1.5-1.6 times of the rated current, the electromagnetic torque ripple is reduced, and the fault ride-through capability of the doubly-fed wind generator during the failure is improved.
Owner:HENAN NORMAL UNIV

SCR denitration ammonia spraying control method, device, equipment and medium

The invention discloses an SCR denitration ammonia spraying control method, device and equipment and a medium. The SCR denitration ammonia spraying control method comprises the following steps: acquiring first nitrogen oxide content data at an outlet of a waste gas pipeline of an SCR denitration ammonia spraying system at the end moment of a current detection period; generating a first control signal when the first nitrogen oxide content data exceeds a maximum preset concentration threshold value, wherein the first control signal is used for controlling a valve of an ammonia water flow regulating valve of the SCR denitration ammonia spraying system to be increased by a first preset opening degree at the end moment of the current detection period; when the first nitrogen oxide content data does not exceed the minimum preset concentration threshold value, generating a second control signal, wherein the second control signal is used for controlling a valve of the ammonia water flow regulating valve to be reduced by a second preset opening degree at the end moment of the current detection period, and the highest preset concentration threshold value is higher than the lowest preset concentration threshold value. The technical effect of high-efficiency and high-accuracy ammonia gas consumption adjustment is achieved.
Owner:SHOUGANG JINGTANG IRON & STEEL CO LTD

Unmanned aerial vehicle cooperative positioning system and method based on graph neural network

The invention discloses an unmanned aerial vehicle cooperative positioning system and method based on a graph neural network, and the system comprises a plurality of unmanned aerial vehicles, a server, and an unmanned aerial vehicle simulation platform. A graph neural network model carried by the unmanned aerial vehicle is obtained through building a neural network training model on the unmanned aerial vehicle simulation platform, so that the unmanned aerial vehicle can autonomously generate a control instruction, and cooperative positioning of multiple unmanned aerial vehicles is realized. According to the unmanned aerial vehicle cooperative positioning system and method based on the graph neural network, a decentralized control system is adopted, the requirement for a server is low, real-time control over the unmanned aerial vehicle can be achieved, the positioning accuracy is high, and the anti-interference capacity is high.
Owner:BEIJING INSTITUTE OF TECHNOLOGYGY

Double-pulse ignition method for actively suppressing swing of pulse force control missile body

The invention relates to a double-pulse ignition method for actively suppressing swing of a pulse force control missile body. The double-pulse ignition method is characterized by comprising the following steps of starting a control cycle, collecting a strap-down detector output signal and a tachometer output signal by a missile-borne computer; calculating delay time deltat1 by the missile-borne computer according to a pulse engine ignition control algorithm, and igniting a first pulse engine; starting timing by the missile-borne computer after the first pulse engine is ignited, and controlling a second pulse engine to be ignited in the same direction after the delay time deltat2 is delayed, wherein the second pulse engine and the first pulse engine are symmetrical in position about the axle of the missile body; ending the control cycle, judging whether a target is hit or not, ending guidance if the target is hit, otherwise, starting the next control cycle after time interval Td, and returning.
Owner:中国北方工业有限公司 +1

Rapid model prediction control method for air separation unit based on FPAA simulation neural network

The invention discloses a rapid model prediction control method for an air separation unit based on an FPAA simulation neural network. The method comprises two parts: offline calculation and online calculation. The offline calculation comprises the calculation of an MPC control parameter and the construction of an analog circuit QP solver; The online calculation comprises state updating, unconstrained optimization, calculation of translation transformation and scale transformation parameters, and QP solving of the analog circuit. The method employs a continuous neural network for solving a QPproblem, and has the natural parallelism. The method solves a problem that the analog circuit achieves the signal restriction of a continuous neural network through the translation transformation andscale transformation. On the basis, the circuit employs an FPAA for designing the analog circuit, thereby achieving the rapid solving of the QP in the MPC. Compared with an existing technology, the method effectively irons out the defects of a discrete neural network, and solves the problems in a better way that a conventional numerical method is low in MPC solving speed and is poorer in real-timeperformance.
Owner:ZHEJIANG UNIV

DC micro network secondary adjusting control method based on line loss optimization

The invention belongs to the interdisciplinary field of a power distribution network technology and an electric power and electronics technology, and especially relates to a DC micro network secondary adjusting control method based on line loss optimization. First of all, a DC micro network system is constructed, an upper-layer control center, according to sampling information of each converter, calculates the line loss power of the DC micro network system; then a controllable voltage source sagging control intercept common mode and a differential mode adjusting amount are calculated; and output voltage of each controllable power supply in a DC micro network is adjusted through sagging control parameters such that the output of each power supply is controlled, the trend on each distribution branch is adjusted accordingly, and the line loss is reduced. According to the invention, the line loss of the DC micro network is optimized under the condition that line impedance and enormous operation information are measured without reliance on high-sensitivity sensors. Experiment results indicate that compared to a conventional DC micro network control method, the control method provided by the invention can effectively reduce the line loss, and the specific reduction amplitude is determined according to the distribution condition of the line impedance and loads.
Owner:TSINGHUA UNIV

A Modular Capacitor Voltage Equalization Control Method for Modular Multilevel Converter

ActiveCN103532419BIncrease control frequencyOvercome the problem of high communication volumeAc-dc conversionCapacitanceCapacitor voltage
The invention discloses a module capacitor voltage sharing control method for a modular multilevel converter. The method comprises the following steps of sequencing all modules in each group according to the magnitudes of module voltage values, and searching for a maximum module voltage value Umax(i) and a minimum module voltage value Umin(i) in each group, wherein i is 1, 2, ..., N; performing voltage sharing processing on the module voltage value of each module according to the maximum module voltage value and the minimum module voltage value in each group to obtain an estimated module voltage value of each group, extracting M corresponding estimated module voltage values from the estimated module voltage values U(i, j) of all the groups according to current directions of bridge arms, extracting the corresponding modules from each group according to the M extracted estimated module voltage values and the current directions of the bridge arms, and putting the extracted modules in all the groups into use, wherein the number of the M estimated module voltage values in each group is equal to that of the extracted modules in the group. According to the method, the communication traffic of a controller can be effectively reduced, and meanwhile, module voltage can be shared.
Owner:深圳市奥特迅科技有限公司

Space micro-newton-level electric propulsion control system

The invention discloses a space micro-newton-level electric propulsion control system which comprises an instruction analysis module, a remote measurement acquisition module, a thrust conversion module, a thrust control module and a DA control module. The instruction analysis module is used for analyzing an instruction sent by a satellite platform and outputting analyzed parameters to the thrust control module; the remote measurement acquisition module is used for controlling the AD acquisition chip, acquiring voltage and current fed back by the thruster, performing mean value processing on the acquired voltage and current, and sending the processed voltage and current to the thrust conversion module; the thrust conversion module is used for converting the received voltage and current subjected to mean value processing into corresponding thrust values and sending the thrust values to the thrust control module; the thrust control module realizes thrust control by selecting open-loop control or closed-loop control, calculates a voltage value based on the received data, and outputs the voltage value to the DA chip control module; and the DA chip control module is used for converting the received voltage value into an N value and outputting the N value to the DA chip, so that the micronewton thrust is output to the thruster.
Owner:NAT SPACE SCI CENT CAS

Modulation function based SVPWM control method for single-phase open-circuit fault of five-phase permanent magnet synchronous motor

The invention discloses a modulation function based SVPWM control method for a single-phase open-circuit fault of a five-phase permanent magnet synchronous motor, and the method is applied to fault-tolerant control over single-phase open-circuit fault of the five-phase permanent magnet synchronous motor, improves the utilization rate of DC voltage and reduces the operation time. The fault-tolerantcontrol system generates a two-phase static coordinate system modulation voltage instruction and a third harmonic space modulation voltage instruction, and carries out preprocessing to obtain a groupof modulation functions with coefficients as constants. During real-time operation, six sectors are determined, modulation functions of the corresponding sectors are directly called, the modulation functions are directly loaded into a comparison value register of each phase of driving pulse, and the comparison value register is compared with a time base counting register to obtain each phase of SVPWM pulse. By simplifying basic space voltage vector action sequence selection, action time calculation and switching action moment conversion processes, an SVPWM modulation calculation program is simplified, SVPWM modulation link operation time and overall control time are reduced, the control frequency under the same controller is improved, and thus more excellent control performance is obtained.
Owner:TIANJIN UNIV

A method and system for compensating angular momentum and moment of spaceborne large inertia rotating load

The invention belongs to the technical field of space-borne load application, and in particular relates to a method and system for compensating the angular momentum and moment of a space-borne large-inertia rotating load. To solve the problem that the existing compensation method cannot meet the load compensation requirements of large inertia and high speed, the system includes the first speed conversion unit, the balance wheel system, the second speed conversion unit and the turntable system; the method process is as follows: The speed is converted to the target speed of the balance wheel, and the balance wheel starts to accelerate to the target speed. The Hall signal output by the balance wheel is used to calculate the speed of the balance wheel in real time, and the real-time speed of the balance wheel is converted to the given speed of the turntable, and the reverse rotation is performed, thereby Ensure that the rotation speed of the turntable is matched and tracked with the rotation speed of the balance wheel in real time during the processes of acceleration, constant speed and deceleration to ensure the compensation effect of residual angular momentum and residual torque.
Owner:XI'AN INST OF OPTICS & FINE MECHANICS - CHINESE ACAD OF SCI

Piezoelectric ceramic actuator steering engine servo mechanism and steering engine servo method

The invention provides a piezoelectric ceramic actuator steering engine servo mechanism and a steering engine servo method and solves problems of a limited response speed of a traditional motor steering engine and obvious response frequency reduction especially under the load condition. A piezoelectric ceramic actuator is employed to drive a steering engine to work, the response speed is greatly improved, aeroelastic control under high frequency response can be satisfied, a new solution scheme is provided for flutter suppression of steering engine servo, and the piezoelectric ceramic actuator steering engine servo mechanism has great application prospects.
Owner:BEIHANG UNIV

Direct prediction torque control method and system for permanent magnet synchronous motor

The invention discloses a direct prediction torque control method and system for a permanent magnet synchronous motor. A prediction model is used for directly performing prediction calculation on torque and stator flux linkage based on eight groups of actual space voltage vectors; an actual space voltage vector screening evaluation function is constructed based on the absolute value constructed by the switching times of the inverter, the stator flux linkage amplitude and the torque estimation offset during actual space voltage vector conversion; the high-concurrency register conversion level digital circuit design and Verilog coding comprise all functional circuit integration modules. The invention discloses an RTL code digital test platform based on a Verilog language. The functionality and comprehensiveness of RTL codes are detected. According to the control system based on the method and the FPGA, the control frequency of the permanent magnet synchronous motor is effectively improved, small torque pulsation is guaranteed, the switching frequency is reduced, and the service life of a power device is prolonged.
Owner:XI AN JIAOTONG UNIV

Control method and control system of foldable arm rest and engineering machinery

The invention discloses a control method of a foldable arm rest. The control method includes a detection step: detecting whether each arm section is in a completely closed state or not, a calculation step: ensuring that the arm section is in a completely folding state when the arm section is not in a completely closed state, obtaining the folding state of each arm section, working out the maximum distance L between the arm rest portion which is between the predetermined arm section and the tail end of the folding arm rest and a hinge point of the root end of the predetermined arm section according to the folding state of each arm section, and working out the allowable maximum angular velocity w when the predetermined arm section moves according to a predetermined linear velocity V and the maximum distance L, and a control step: controlling an actuating part which drives the predetermined arm section, and enabling the predetermined arm section to move at an angular velocity which is less than or equal to the maximum angular velocity w. The invention correspondingly discloses a control system of the foldable arm rest and engineering machinery. The control method and the control system has the advantages of being capable of improving folding speed of the foldable arm rest and working efficiency, easy to control, low in cost and good in stability.
Owner:ZOOMLION HEAVY IND CO LTD

Secondary regulation control method of DC microgrid based on line loss optimization

The invention belongs to the interdisciplinary field of a power distribution network technology and an electric power and electronics technology, and especially relates to a DC micro network secondary adjusting control method based on line loss optimization. First of all, a DC micro network system is constructed, an upper-layer control center, according to sampling information of each converter, calculates the line loss power of the DC micro network system; then a controllable voltage source sagging control intercept common mode and a differential mode adjusting amount are calculated; and output voltage of each controllable power supply in a DC micro network is adjusted through sagging control parameters such that the output of each power supply is controlled, the trend on each distribution branch is adjusted accordingly, and the line loss is reduced. According to the invention, the line loss of the DC micro network is optimized under the condition that line impedance and enormous operation information are measured without reliance on high-sensitivity sensors. Experiment results indicate that compared to a conventional DC micro network control method, the control method provided by the invention can effectively reduce the line loss, and the specific reduction amplitude is determined according to the distribution condition of the line impedance and loads.
Owner:TSINGHUA UNIV

A switching power supply control circuit

The invention discloses a switching power supply control circuit, which is applied to a current-controlled switching power supply, and is characterized in that it includes a trigger circuit and a current source control circuit, and the trigger circuit samples the state signal of the working state pin of the switching power supply control chip through its input terminal , with reference voltage V REF comparison, when the status signal does not reach the reference voltage V REF , its output terminal provides current for the input terminal of the current source control circuit, and the current source control circuit works under the action of the current source to increase the current value of the current control pin of the switching power supply control chip; when the state signal reaches the reference voltage V REF When , the output terminal of the trigger circuit does not provide a current source for the input terminal of the current source control circuit, and the current source control circuit does not work. The invention not only realizes the purpose of adjusting and controlling the output frequency when the switching power supply is in the start-up stage, but also solves the problems of large ripple noise and poor dynamic characteristics of the switching power supply at no-load or light load.
Owner:MORNSUN GUANGZHOU SCI & TECH

Switching power supply control circuit

The invention discloses a switching power supply control circuit. The method is applied to a current-controlled switching power supply. The switching power supply control circuit is characterized in that the switching power supply control circuit comprises a trigger circuit and a current source control circuit, and the trigger circuit samples a state signal of a working state pin of the switchingpower supply control chip through the input end of the trigger circuit; compared with a reference voltage VREF, when the state signal does not reach the reference voltage VREF, the output end of the trigger circuit provides a current for the input end of the current source control circuit, the current source control circuit works under the action of the current source, and a current value of a current control pin of the switching power supply control chip is increased; and when the state signal reaches the reference voltage VREF, the output end of the trigger circuit does not provide a currentsource for the input end of the current source control circuit, and the current source control circuit does not work. According to the invention, the output frequency can be adjusted and controlled when the switching power supply is in a starting stage, and the problems of large ripple noise and poor dynamic characteristics of the switching power supply in a no-load or light-load state can be solved.
Owner:MORNSUN GUANGZHOU SCI & TECH

Double-tube independent interleaving control method for electromagnetic attraction suspension system

InactiveCN102910085BIncrease the number of adjustmentsAdd control variableMagnetic holding devicesElectric propulsionDouble tubeControl system
The invention discloses a double-tube independent interleaving control method for an electromagnetic attraction suspension system. The method aims at carrying out independent control on the current of the conventional electromagnetic attraction suspension control system by virtue of an upper switch tube and a lower switch tube of an H-shaped chopper in links, and the sampling time, calculating time and implementation time in control are subjected to interleaving. By adopting the independent interleaving control, the control and switching frequency of the system can be equivalently increased without changing the structure of a main circuit and the switching frequency of single tube, so that small pulse and zero level can be naturally generated; and by adopting the method, the static current ripple can be controlled, so that the error in current tracking can be reduced, and the fastest speed in current tracking can be kept, the complexity and safety of the system are maintained, and as a result, the performance of the system is improved.
Owner:SOUTHWEST JIAOTONG UNIV
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