Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

94results about How to "Reduce the amount of online calculations" patented technology

KNN-based text classification method

The invention discloses a KNN-based text classification method which is suitable for nuclear safety software verification and reliability verification. The KNN-based text classification method comprises a training process processing step and a test process processing step: representing training sample data sets by information of original texts and all the titles in the texts; and constructing two DBM models according to characteristic hierarchical structures in the texts from shallow to deep, extracting and storing deep characteristics with low dimensionality and high discrimination, and determining the categories of to-be-tested texts through considering the contribute brought from text titles to the similarity calculation via proper weights in the test process. According to the method disclosed in the invention, information of the text titles are fully utilized, the classification performance, relative to the condition of taking the shallow characteristic vectors as training sets, is remarkably improved, and meanwhile, the storage demand and online calculation amount are reduced at the same time, so that the problem of characteristic vector high-dimensionality disaster is solved and the classification correctness is improved; and the method can be used for the matching of rules in safety level software reliability evaluation analysis and the establishment of a failure mode library.
Owner:CHINA TECHENERGY +1

Method for intelligently calculating, predicting and controlling steam temperature of power station boiler

InactiveCN106765052AImproved dynamic tuning performance and stabilityEasy to programSuperheating controlTime delaysSteam temperature
The invention discloses a method for intelligently calculating, predicting and controlling steam temperature of a power station boiler. The method comprises the following steps: step one, determining a sampling time interval Ts of prediction and control; step two, identifying local models Gm described by an input-output difference equation form of a steam temperature system of a unit operating under M typical load conditions; step three, tacking, simulating tracking control of square-wave signals of all the local models Gm by using model prediction control; step four, training an intelligent calculation model by using control simulation data of all the local models GM to form an intelligent prediction controller IPC; step five, identifying a nonlinear inverse model of a regulation valve; and step six, taking the trained intelligent prediction controller IPC as a real-time controller to obtain a temperature-reducing water valve opening degree actual command u(t) which can be implemented at current sampling time. The method has the advantage that the problem of low control performance of steam temperature caused by the change of steam temperature object with long time delay, great inertia and time-variant characteristic along with the loads of the unit can be avoided.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

Energy management method of hybrid electric vehicle based on power spectrum self-learning prediction

The invention provides an energy management method of a hybrid electric vehicle based on power spectrum self-learning prediction. The energy management method comprises the following steps: step 1, calculating current driving demands of the vehicle, and identifying current calendar time, moment and the like; step 2, receiving the information about a future running route and a future running direction of the vehicle, climatic information and the information about whether the current day is a workday or not; step 3, making similarity judgment on future running conditions and corresponding records in a self-learning power-spectrum database; step 4, executing an energy management strategy based on rules; step 5, performing power-spectrum prediction, and power control and energy management of the hybrid electric vehicle based on a self-learning power spectrum; step 6, establishing a power-spectrum database based on self-learning; and step 7, outputting a control-instruction rotating speed or torque to a power supply module so as to realize power control and optimal energy management. The energy management method overcomes the defects existing in a conventional energy management strategy of a hybrid electric vehicle, realizes the self-adaption optimal energy control for the working conditions of the hybrid electric vehicle, and is liable to be applied to a real vehicle.
Owner:SHANGHAI JIAO TONG UNIV +1

Multivariable non-linear system prediction function control method based on Hammerstein model

The present invention provides a controlling method of a multivariate nonlinear system prediction function based on the hammerstein model, characterized in that the method includes following steps: (1) establishing the hammerstein model according to the process characteristic and the input output data; (2) solving the prediction function control rate of the multivariate linear subsystem according to the hammerstein model linear part model parameters, set values and practical process output of; (3) solving the equation V(k)=F(U(k)) to obtain optimal control law U(k) according to the hammerstein model nonlinear part model parameters and the multivariate linear multivariate nonlinear system prediction function control rate; (4) solving and implementing the optimal control law according to multivariate nonlinear system prediction function controller. The invention realizes one prediction function control of multivariate nonlinear system, realizing that the control problem of the nonlinear system is transformed to the linear system control problem and the solving problem of the nonlinear equation, improving the solving speed of the optimal control law, reducing the on-line computational complexity, ensuring the real-time requirement of the control system.
Owner:ZHEJIANG UNIV

Intelligent calculating prediction control method of thermal power generating unit coordination control system

InactiveCN106406101AImproved dynamic tuning performance and stabilityEasy to programAdaptive controlInput/outputGenerating unit
The invention discloses an intelligent calculating prediction control method of a thermal power generating unit coordination control system. The method comprises the following steps of step1, determining a sampling time interval Ts of prediction control; step2, through an unit characteristic test, acquiring a local model Gm described by an input-output difference equation form of a boiler steam turbine system under M typical load conditions; step3, using model prediction control to carry out square wave signal control simulation on all the local models Gms in the step2; step4, using control simulation data of all the local models Gms to train an intelligent calculating model so as to form an intelligent prediction controller IPC; step5, taking the intelligent prediction controller IPC acquired from the step4 through training as a real-time controller, collecting needed input signals and sending into the intelligent prediction controller IPC, wherein the intelligent prediction controller IPC automatically calculates and acquires a control increment instruction delta u (t) needed for adjusting the boiler steam turbine under any conditions. In the invention, accuracy is high, a reaction speed is fast and an on-line calculated amount is small.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

Prediction-function-based variable-domain fuzzy PI control method of alternating current servo motor

The invention discloses a prediction-function-based variable-domain fuzzy PI control method of an alternating current servo motor. A PI controller, a variable-domain fuzzy controller and a predictionfunction controller are arranged. The PI controller is used as a main controller to adjust the rotating speed of the servo motor; the prediction function controller predicts the future state of the system according to a current input instruction, a control signal and a feedback output of the system; the variable-domain fuzzy controller uses prediction information as input to adjust the gain of the PI controller in an on line manner. Meanwhile, a variable-domain telescopic factor is designed, the discourse domain of the fuzzy controller is adjusted online in advance by utilizing prediction information, and fuzzy rules for adjusting PI control gain are indirectly increased. Compared with traditional PI control and fuzzy PI control, the variable-domain fuzzy control method inherits the advantage of high precision of variable-domain fuzzy control and the dynamic response performance and disturbance resistance are enhanced; and the method has more outstanding advantages for application occasions with uncertain disturbance and large nonlinearity.
Owner:HUAZHONG UNIV OF SCI & TECH

Method for optimizing ignition position of free piston engine control system based on extremum searching

The invention discloses a method for optimizing an ignition position of a free piston engine control system based on extremum searching and belongs to the technical field of engines. The invention aims to provide a method for optimizing an ignition position of a free piston engine control system based on extremum searching. The method is characterized by enabling the free piston engine to stably operate at each operating point by controlling a management system, finding an optimal ignition position of the free piston engine by using an extremum searching strategy and completing map calibration. Two free piston components are meshed with each other via a gear and two racks; two pairs of pistons are subjected to four-stroke operation through mirror movement; an electromagnetically-driven variable-valve timing mechanism is mounted at the top of each cylinder; a geometric midpoint between a left cylinder and a right cylinder is an original point of a piston movement position; the extreme position which the pistons and connection rods reach during moving right is a lower stop point; the extreme position which the pistons and connection rods reach during moving left is an upper stop point. Through the method, the stability and the economy of operation of the free piston engine can be improved; the resources and the time consumed in the map calibration process of the ignition position can be reduced.
Owner:JILIN UNIV

Double-layer control system for load tracking for supercritical thermal power unit turbine-boiler system

The invention discloses a double-layer control system for load tracking for a supercritical thermal power unit turbine-boiler system. The double-layer control system comprises an upper-layer controller and a lower-layer controller, and is characterized in that the upper-layer controller is an economic linear model predictive controller (ELMPC), the lower-layer controller is an L1 adaptive controller; the ELMPC builds a local linearized model with disturbing items of the turbine-boiler system, plans an optimal state and an output track of the system in a future period of time by taking the optimal economy in the future period of time as a target, acquires a corresponding optimal control variable, and transmits the optimal control variable, the corresponding optimal state of the system and the output track to the lower-layer controller; and the lower-layer controller is an L1 adaptive controller, and the L1 adaptive controller adds an adaptive correction value on the basis of the control variable planned by the upper-layer controller according to the optimal state and the output track which are transmitted by the upper-layer controller and an actual unit state and an output measurement value so as to be used for updating a prediction model of the upper layer.
Owner:SOUTHEAST UNIV

Inversion range migration method for synthetic aperture radar large-scale scene deception jamming

Provided is an inversion range migration method for a synthetic aperture radar (SAR) large-scale scene deception jamming. The method comprises steps of: 1, constructing a jammer deception template according to a false electromagnetic characteristic which is planned to be generated by a jamming party in a radar image; 2, computing equidistant sampling values of a complementary focusing filter HHdiff (k, kx) on a two-dimension frequency domain (k, kx) plane; 3, computing equidistant sampling values of a consistent focusing filter HHbulk (k, kx) on a two-dimension frequency domain (k, kx) plane, and multiplying the equidistant sampling values of the consistent focusing filter HHbulk (k, kx) on the two-dimension frequency domain (k, kx) plane by the equidistant sampling values of the complementary focusing filter HHdiff (k, kx) on the two-dimension frequency domain (k, kx) plane acquired in the step 2; and 4, performing azimuth inverse Fourier transformation on a result acquired in the step 3 and multiplying a transformed result by the equidistant sampling values of a jammer blanking filter Hhelim (k, x) on a distance frequency domain (k, x) plane. The invention provides the SAR large-scale scene deception jamming method for overcoming defects in the prior art. The method computes jammer system frequency response accurately and high efficiently in order that a radar, when having high resolution, a large squint angle, and a long synthetic aperture, may satisfy computational complexity and focusing effects.
Owner:NAT UNIV OF DEFENSE TECH

Online planning method for reentry trajectory of aircraft based on particle swarm optimization algorithm

InactiveCN107590297AAvoid Converging to Local OptimaAvoid problems such as large amount of calculationForecastingBiological modelsTechnical standardInversion Time
The invention provides an online planning method for reentry trajectory of an aircraft based on a particle swarm optimization algorithm. The method comprises the following steps of 1, determining an envelop range of an initial condition of reentry according to an reentry task requirement of the aircraft; 2, determining the sizes of piecewise constants of a heeling angle and the maximum number of inversion times of a heeling angle symbol according to the envelop range of the initial condition of reentry; 3, dividing the envelop range of the initial condition of reentry into grids, and ensuringthat an original envelop peak is a sub-envelop peak; 4, using each sub-envelop peak as the initial condition of reentry, and using the particle swarm optimization algorithm to design an reentry standard trajectory of the aircraft offline; 5, verifying validity of envelopment range division and the reentry standard trajectory via offline digital simulation; and 6, statistically analyzing a simulation result, and if the result does not meet an expected design requirement, returning to the step 3 to redivide sub-envelops; and if the result meets the expected design requirement, ending design. Themethod provided by the invention has the advantages of being small in online computing amount and high in placement accuracy of standard trajectory generated online.
Owner:BEIJING SPACE TECH RES & TEST CENT

Incremental direct prediction speed control method suitable for permanent magnet motor system

The invention discloses an incremental direct prediction speed control method suitable for a permanent magnet motor system. The incremental direct prediction speed control method mainly comprises an incremental speed prediction model, two-stage exhaustion optimization and a boundary vector synthesis method. The incremental speed prediction model established by adopting an incremental modeling method can greatly reduce the multi-step prediction calculation amount while meeting the speed prediction precision. According to two-stage exhaustion optimization, the determination of a system output vector from an expansion control set is completed by two steps, so that an exhaustion optimization method corresponding to the expansion control set is designed. According to the boundary vector synthesis method, the amplitudes and phase angles of all virtual vectors in a control set can be determined on the basis of only utilizing a basic voltage vector without complex trigonometric function operation. According to the invention, the excellent rotating speed dynamic control performance in the prior art can be kept, the online calculation amount for achieving multi-step speed prediction can be greatly reduced, and the stability of prediction speed control is effectively guaranteed.
Owner:TIANJIN POLYTECHNIC UNIV

Constraint condition-containing motor control method and constraint condition-containing motor control system

The invention discloses a constraint condition-containing motor control method and a constraint condition-containing motor control system. The constraint condition-containing motor control method is characterized by setting a voltage constraint condition and a current constraint condition of a motor by considering a safe working range of the motor; firstly, collecting the current and the rotating speed of the motor at the current time k, and solving the control voltage of a dead-beat control algorithm at the time k; then, when the control voltage of the dead-beat control algorithm at the time k is positioned in a voltage vector space determined by the voltage constraint condition and is also positioned in a voltage vector space determined by the current constraint condition, processing a constraint problem that the motor faces by adopting the dead-beat control algorithm, otherwise, processing the constraint problem that the motor faces by adopting a finite set model prediction control algorithm. Since the finite set model prediction control algorithm is capable of conveniently processing and controlling the existing constraint problem, and the dead-beat control algorithm has good dynamic tracking performance, by combining the advantages of the finite set model prediction control algorithm and the dead-beat control algorithm, the motor is enabled to always have good running performance within a safe running region.
Owner:HUAZHONG UNIV OF SCI & TECH

Dynamic matrix control (DMC) engineering method based on model simplification and prediction error correction

The invention discloses a dynamic matrix control (DMC) engineering method based on model simplification and prediction error correction, which relates to the DMC engineering method and solves the existing problems as follows: (I) DMC cannot be applied in certain rapid control processes; (II) the indexes of the DMC for instant error correction lag are influenced in predictive control; (III) although the real-time performance is improved by the model simplification, but the precision and the robustness of the system are reduced; and (IV) bottom control is hard to realize. The DMC engineering method based on the model simplification and the prediction error correction comprises the following concrete steps: (I) acquiring the step response curve of the system, and establishing a model of which the order is N; (II) simplifying the model, and reducing the order of the model to n; (III) simplifying the rolling optimal control of the model; (IV) establishing a prediction error model; (V) judging whether model testing passes or not; if the model testing does not pass, returning to the step (IV); and if the model testing passes, executing the comprehensive control of the model simplification and the prediction error correction; and (VI) judging whether a control effect reaches the requirement or not; if the control effect does not reach the requirement, returning to the step (II); and if the control effect reaches the requirement, enabling the control effect to be used for control. The DMC engineering method based on the model simplification and the prediction error correction is used for DMC engineering control.
Owner:HARBIN INST OF TECH

Control system and method for fixed-point parking of stratospheric aerostat

The invention belongs to the technical field of automatic control, and discloses a control system for fixed-point parking of a stratospheric aerostat. The control system comprises a height maintaining module connected with a vector thrust composite module, and an attitude tracking module; the attitude tracking module is connected with a pitch roll control module; the vector thrust composite module is connected with a nonlinear mapping module; the nonlinear mapping module and the pitch roll control module are connected with a master controller; the master controller is connected with the height maintaining module and the attitude tracking module through a state measuring module; the height maintaining module and the attitude tracking module obtain a relationship between the target height, the attitude and the tracking acceleration through a PID tracking algorithm; the vector thrust composite module and the pitch roll control module obtain the tracking control force and a slider position through a dynamic inverse method; the nonlinear mapping module converts the control force into the magnitude and a corner of each vector thrust; and the state measuring module detects the current state of the aerostat and feeds the current state back to the height maintaining module and the attitude tracking module to implement closed loop control.
Owner:SHANGHAI UNIV OF ENG SCI

Quick multivariable predication control method for ethylene cracking furnace

The invention relates to a quick multivariable predication control method for an ethylene cracking furnace. The method has an offline link and an online link. In the offline link, a dynamic mathematic model and a static mathematic model of a production process of the ethylene cracking furnace are obtained through an analysis or recognition method and control parameters are set. In the online link, a prediction value is calculated and output according to a measurement value of an ethylene cracking furnace control system (DCS), a predication error is calculated based on the difference between the predication value and the measurement value and accordingly a static output predication value is corrected; and then a static control input predication value is calculated through static optimization or a direct inversion method; and finally a control input value of a current moment is calculated according to a given control parameter, the dynamic performance of the control input value is corrected through a lead-lag link and the corrected value is then transmitted to the DCS. According to the invention, the calculation complexity for multivariable prediction control is simplified and the control period of multivariable prediction control is reduced distinctively, and control problems in quick reaction processes of the ethylene cracking furnace and the like can be solved effectively.
Owner:MICROCYBER CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products