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78results about How to "Meet the rapidity requirements" patented technology

Intelligent board feeding and discharging transfer robot

The invention relates to an intelligent board feeding and discharging transfer robot. The intelligent board feeding and discharging transfer robot is characterized in that the transfer robot comprisesa rack, an X-axis movement module, a Y-axis movement module, a Z-axis movement module and a target storage tank; the X-axis movement module, the Y-axis movement module and the Z-axis movement moduleare mounted on the rack, and the target storage table is connected with the rack; the X-axis movement module and the Y-axis movement module are driven by a stepping motor provided with an encoder to slide in the horizontal direction, and the Z-axis movement module is driven by a drive motor to slide in the vertical direction; the positions, measured by the X-axis movement module, the Y-axis movement module and the Z-axis movement module through a PLC or NC system at fixed time intervals, of a machined are used as target coordinates, and then position control in the axial direction is conductedaccording to the target coordinates. The intelligent board feeding and discharging transfer robot has the advantages that firstly, the torque of the stepping motor is large so that the speed can be adjusted conveniently, and the speed is high; secondly, a cylinder is high in driving speed and bearing capacity and durable; thirdly, full automation is achieved, and labor consumption is reduced; andfourthly, the PLC or NC system is used for establishing a space coordinate system of the spatial positions of the X-axis movement module, the Y-axis movement module and the Z-axis movement module andthe material storage position, a position control program is written, and thus full automation is achieved.
Owner:GUANGDONG YIHUA TIMBER IND

Adaptive kernel function and instantaneous frequency estimation-based fault arc detection method of photovoltaic system

The invention discloses an adaptive kernel function and instantaneous frequency estimation-based fault arc detection method of a photovoltaic system. The adaptive kernel function and instantaneous frequency estimation-based fault arc detection method comprises the steps of acquiring a signal xt by a time window with TNCT length, performing non-linear frequency modulation wavelet transform to obtain a iteration time-frequency diagram of the xt, and constructing characteristic quantity, used for judging moment when frequency spectrum energy is increased, according to a frequency component in theselected iteration time-frequency diagram; and obtaining a corresponding matrix distribution form of the xt in the time-frequency domain by adaptive optimal kernel time-frequency distribution after an abrupt changing point where the energy is increased is found out, performing square sum on the matrix according to time dimension to obtain a line vector, selecting a plurality of frequency bands, performing frequency-dimensional integral operation on each frequency band to obtain a plurality of characteristic values input into a trained naive bayesian model, and judging a state of the photovoltaic system in a current time frame. By a plurality of effective time-frequency characteristics, a fault arc in the photovoltaic system is accurately identified, meanwhile, no misoperation under various types arc working conditions also can be ensured, and the photovoltaic system safely and stably run.
Owner:XI AN JIAOTONG UNIV

Initial alignment method for MEMS-IMU

The invention discloses an initial alignment method for an MEMS-IMU. Through the initial alignment method, the initial rough alignment time of a strapdown inertial system is further shortened, and the precision of the strapdown inertial system is further improved. The initial alignment method comprises the following steps that 1, sensor data are acquired, wherein the sensor data comprise the data of an MEMS gyroscope and an MEMS accelerometer; 2, initial alignment coordinate systems are established, wherein the initial alignment coordinate systems comprise the solidified carrier coordinate system, the earth coordinate system, the navigation coordinate system and the carrier coordinate system; 3, initial alignment objective functions are established, and an optimal speed reducing method of quick alignment is constructed; 4, a parameter equation of the optimal speed reducing method is determined through the complementary filter principle; 5, a carrier attitude angle is resolved through an quaternion updating algorithm, and calculation of an initial attitude matrix is achieved. According to the initial alignment method for the MEMS-IMU, the calculation precision and efficiency of an initial alignment algorithm are effectively improved, and the application range is wide.
Owner:HUAWEI TEHCHNOLOGIES CO LTD

Voltage acceleration inverse time-delay over-current protection method used for micro power grid

The invention relates to the field of distribution network relay protection of an electric power system and relates to a voltage acceleration inverse time-delay over-current protection method used for a micro power grid. According to voltage and current information acquired by a protection mounting point, after a short circuit fault occurs and is judged to be a positive directional fault, a method for calculating protection time-delay operation time comprises the step of multiplying an existing inverse time-delay over-current protection setting formula by a voltage accelerated factor to obtain an accelerated operation time, wherein the minimum value of per-unit values of three phase voltages and three line voltages at the protection mounting point is taken as the voltage accelerated factor. The voltage acceleration inverse time-delay over-current protection method used for the micro power grid has the advantages that the time for eliminating the short circuit fault at line exit is very short, the delay-free operation is achieved, the faults at other points on the line and various faults also can be quickly processed, and the demand on rapidity is met.
Owner:TIANJIN UNIV

Rapid protection method and system for DC circuit of multi-port flexible DC power grid

The invention discloses a rapid protection method and system for a DC circuit of a multi-port flexible DC power grid. The rapid protection method comprises the following steps of acquiring a voltage and a current of a protection component connected with a positive electrode and a negative electrode of a DC power transmission line; starting a protection device when a short-circuit fault occurs in the power transmission line, and extracting a voltage sampling value and a current sampling value at set time after the fault; calculating FPT according to the voltage sampling value extracted after the fault, and calculating a ratio between a positive current difference value and a negative current difference value at initial time and last time in a sampling data window according to the current sampling value extracted after the fault; comparing the FPT obtained by calculation with a set FPT threshold value, and distinguishing an internal fault and an external fault; and comparing the ratio between the positive current difference value and the negative current difference value which are obtained by calculation with a set threshold value, and distinguishing a fault level. The protection method is rapid in action speed, and the rapidness requirement of the multi-port flexible DC power grid on protection can be met only according to single-end voltage and current of a protected circuit.
Owner:SHANDONG UNIV +2

Limit power calculating method of associated electricity transmission cross-section based on parallel calculating model

ActiveCN102170131AComputational Strategies for Narrowing the Search Control SpaceQuick calculationSpecial data processing applicationsAc network circuit arrangementsTransient statePower added
The invention belongs to the power system calculating and analysis technology field, and is applicable to calculate limit powers of associated electricity transmission cross-sections considering static, transient and dynamic security and stability constraints. The limit power calculating method of associated electricity transmission cross-section based on parallel calculating model comprises the steps of firstly calculating a static security limit, and then calculating security and stability limits of the transient and dynamic, on the basis of estimating the power increasing amount of each cross-sections considering over loading security of equipment; classifying the power increasing space of each cross-sections in turn according to the examined failure number and the example calculating capability of a parallel processing platform, and carrying out security and stability calculations for the run modes of different electricity transmission power combinations of each cross-sections by parallel example; judging whether to carry out security and stability calculations of the next round according to the precision requirement of limit calculation after all examples of the round being calculated, and filtering the examined failure set before each round of calculation; and finally, calculating mutual influence factors between limit powers of each cross-sections by analyzing the limitcalculation process information.
Owner:NARI TECH CO LTD

Transient, dynamic stabilization aid decision-making automatic searching method based on parallel calculation

The invention relates to a method for automatically searching assistant decisions for transient and dynamic stability based on parallel computation. Based on power flow and stability data of a power grid and aimed at the problems of transient stability and dynamic stability, the method adopts large-scale parallel computation processing technology as well as human experience and a specific computation method to realize automatic identification of adjusting elements and automatic search of feasible adjustment methods, so as to achieve off-line transient stability analysis of an auxiliary electric power system and actual operation instruction.
Owner:CHINA ELECTRIC POWER RES INST +1

Planar three-degrees-of-freedom space robot inverse kinematics solution method

InactiveCN106228260AMeet the requirements of rapidityGlobalForecastingGeometric relationsThree degrees of freedom
The invention provides a planar three-degrees-of-freedom space robot inverse kinematics solution method. First, a general planar three-degrees-of-freedom space robot is equivalent to a ground fixed base robot using a virtual mechanical arm method; then, the self-motion characteristics of the planar three-degrees-of-freedom space robot are analyzed, and the geometric relational expression between joint angles of the equivalent space robot is deduced under the condition that the initial base attitude angle and the end manipulator position are given; and finally, all combinations composed of three joint angles, namely, all kinematics inverse solutions, are obtained. Through the method, all kinematics inverse solutions can be calculated out simply and efficiently under the condition that the position of an end manipulator of a planar three-degrees-of-freedom redundant space robot is given, and thus, robot path planning problems related to obstacle avoidance, singular avoidance, joint limit avoidance and other optimization indexes can be studied.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Power system grouping and stability margin evaluation system and power system grouping and stability margin evaluation method based on wide area measurement system (WAMS)

Provided are a power system grouping and stability margin evaluation system and a power system grouping and stability margin evaluation method based on a wide area measurement system (WAMS). The power system grouping and stability margin evaluation system comprises a WAMS data platform, and a pretreatment unit and a transient analysis unit are sequentially connected at the back of the WAMS data platform. The WAMS data platform, the pretreatment unit and the transient analysis unit perform bi-directional transmission of information with a state quantity deposit unit. The method comprises: the WAMS data platform measures power-angle values of a machine set, the power-angle values are transmitted to the transient analysis unit after processed by the pretreatment unit, rotor angles of the machine set relative to local inertia center coordinates are calculated through the transient analysis unit and ranked from big to small, (n-1) angle clearances are calculated, the first three clearances are selected to serve as a leading mode at the moment, then an equivalent system trajectory corresponding to the leading mode is calculated, and finally a stability margin of the equivalent system trajectory is calculated. A network structure of a power system and models and parameters of elements do not need obtaining in advance, users do not need to install a WAMS device on each machine set, and grouping calculation can be performed quickly in real time after the system is disturbed or fails.
Owner:XI AN JIAOTONG UNIV +2

Identification and judgment method for switching into fault protection

The invention discloses an identification and judgment method for switching into fault protection. A Prony analysis method is used for current waveform fitting and acquiring frequency, amplitude, attenuation factor and phase characteristic values of current components, criteria of switching into line fault protection are proposed by the aid of frequency, amplitude, attenuation factor and phase characteristic value parameters, and frequency domain characteristics of signals are identified. By the aid of a large number of simulation experiments, current waveforms of line no-load switching-in, single-phase fault and three-phase fault lines with fault distances of 10km, 50km, 90km, 100km, 200km, 300km and 400km are simulated respectively and fitted by the Prony analysis method, and frequencies, amplitudes, attenuation factors and phases of the current components are extracted. The criteria of switching into line fault protection are proposed by the parameters, and simulation results prove accuracy and reliability of the criteria.
Owner:LOGISTICAL ENGINEERING UNIVERSITY OF PLA

Method for identifying bipolar short-circuit fault in direct current line

InactiveCN107478950AMeet double pole short circuit faultMeet the rapidity requirementsFault locationEngineeringVoltage variation
The invention relates to a method for identifying a bipolar short-circuit fault in a direct current line. The method includes the steps of acquiring a negative electrode bus voltage, a current, a voltage change rate, and a current change rate; judging whether positive and negative electrode bus voltage change rates and current change rates satisfy set fault identification pre-judgment conditions; if the fault identification pre-judgment conditions are satisfied, judging whether the positive and negative electrode bus voltages and currents satisfy set fault identification pre-judgment conditions; and if the fault identification pre-judgment conditions are satisfied, judging that a bipolar short-circuit fault occurs to the system. According to the invention, whether the bipolar short-circuit fault occurs to the system is pre-judged according to the positive and negative electrode bus voltage change rates and current change rates, then whether the bipolar short-circuit fault occurs to the system is further determined through the positive and negative electrode bus voltages and currents, the fault identification can be quickly and accurately completed within 0.1ms, and the requirements of quick and accurate detection of the bipolar short-circuit fault in a DC circuit breaker DC line can be satisfied.
Owner:XUJI GRP +3

Key updating method and system for sensor node

The invention discloses a key updating method and system for a sensor node. The method comprises the following steps of: sending a key updating request to a management platform by the sensor node; authenticating the identification of the sensor node by the management platform, randomly generating an Ni-bit updating key for the sensor node after the authentication passes, encrypting the updating key, and sending ciphertext information obtained by encryption to the sensor node; and deciphering the ciphertext information by the sensor node to obtain the updating key, and updating an old key by using the updating key. According to the key updating method disclosed by the invention, the updating time is shortened, the node energy consumption and the communication overhead are reduced, and the network operation efficiency is improved.
Owner:ZTE CORP

Self-adaptive initial alignment method of combined inertial navigation system suitable for satellite communication in motion

ActiveCN107741240AShorten the timeApplicable to actual useMeasurement devicesSelf adaptiveSatellite
The invention relates to a self-adaptive initial alignment method of a combined inertial navigation system suitable for satellite communication in motion. The method comprises the following steps: (1)defining coordinate systems; (2) obtaining a conversion matrix from an inertial coordinate system to a navigation coordinate system; (3) obtaining a conversion matrix from a base relation coordinatesystem to the inertial coordinate system; (4) obtaining a conversion matrix from a carrier coordinate system to a base relation coordinate system; (5) calculating an average value of conversion matrices from multiple carrier coordinate systems to the base relation coordinate system; (6) calculating an error of a conversion matrix from the base relation coordinate system to the inertial coordinatesystem; (7) setting a threshold value and comparing the threshold value with the error; and (8) obtaining a conversion matrix from the carrier coordinate system to a navigation coordinate system according to the steps (2), (3) and (4) so as to realize initial alignment of a carrier. The method makes use of the characteristic of slow change of a projection of a gravity acceleration on a base inertial system, and merges judgments of dynamic characteristics to adapt to satellite communications in motion in different states.
Owner:CHENGDU GLOBAL WAY COMM TECH

Fault location method and system suitable for sectional power supply mode of high-speed railway

InactiveCN109901018ALow investment costMeet the rapidity requirements of fault locationFault locationCable fault locationDistance based
The invention discloses a fault location method and system suitable for a sectional power supply mode of a high-speed railway. The fault location system comprises sectional protection devices arrangedat the two sides of a sectional protection section with each station being as a boundary, wherein the sectional protection devices are used for judging fault point distance, fault type and fault direction. The fault location method is characterized in that the sectional protection devices at the two side of the corresponding section line judge the fault type and fault direction; and the sectionalprotection devices at the two sides of the corresponding fault section line calculate fault point distance based on a current value obtained at the tripping time. The position of the fault point is calculated by utilizing the current value of each wire at the wire outgoing end in sectional protection tripping data at the two sides of the fault section, and fault type and fault direction can be determined, thereby realizing fault location for the sectional power supply mode.
Owner:NARI NANJING CONTROL SYST

Unmanned aerial vehicle real-time obstacle avoidance control method in continuous obstacle environment

The invention relates to a real-time obstacle avoidance control method for an unmanned aerial vehicle in a continuous obstacle environment, which belongs to the technical field of airborne obstacle avoidance of the unmanned aerial vehicle. The method comprises the steps that a mathematical model of the unmanned aerial vehicle obstacle avoidance system is established by using the spatial position relationship and the kinematics equation of the unmanned aerial vehicle; an unmanned aerial vehicle obstacle avoidance guidance law is designed by using the characteristic of fast convergence of the multi-power sliding mode approach law; at the same time uncertainties caused by sensor errors, system modeling and the like are considered; and a super-spiral interference observer is introduced to estimate and compensate the uncertainties in the system. The method enables the unmanned aerial vehicle to avoid continuous obstacles in real time in an accurate manner, does not cause excessive maneuvering of the unmanned aerial vehicle, and is robust to system uncertainties caused by sensor errors.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Automatic inspection system for fast grain storage

The invention discloses an automatic inspection system for fast grain storage. The system comprises an automatic sampling device, an automatic testing device and a control device, wherein the automatic testing device comprises a grain conveying mechanism and a grain testing mechanism; the grain conveying mechanism comprises a first grain buffer, a second grain buffer, grain conveying pipelines and a power air source; the grain test mechanism comprises an impurity detection device and a moisture detection device; a discharging port of the automatic sampling device is connected with a feeding port of the first grain buffer; a discharging port of the first grain buffer is connected with a feeding port of the impurity detection device through a valve; a discharging port of the impurity detection device is connected with a feeding port of the second grain buffer through one grain conveying pipeline; the moisture detection device is arranged below the second grain buffer; and a discharging port of the the second grain buffer is connected with a feeding port of the moisture detection device through a valve. According to the automatic inspection system for fast grain storage, automatic sampling and testing in the grain purchasing process is realized, so that the waiting time of grain storage is reduced, and the grain purchasing efficiency is improved.
Owner:ZHENGZHOU XINSHENG ELECTRONICS TECH

Lead screw push rod type aircraft head deflection driving device

InactiveCN104229145AMeet the requirements of rapiditySatisfy the requirements of control for its rapidityAircraft power transmissionControl signalDeflection angle
The invention discloses a lead screw push rod type aircraft head deflection driving device. The aircraft head deflection driving device can generate a greater deflection angle and can provide a greater overload, and the rotation in the aircraft head deflection angle being 0 to 15 degrees and the head deflection azimuth angle being 0 to 360 degrees can be realized; in addition, when the aircraft head requires any deflection, aircraft head installing equipment can be enabled not to interfere with an aircraft head case. When the aircraft head needs to deflect, an aircraft computer sends out signals, a power mechanism receives control signals, the power mechanism drives a lead screw pushing tube to rotate, a lead screw steering mechanism converts the rotating movement into the vertical movement of a push rod mechanism, a push rod aircraft head and a rotating connecting arm mechanism rotate around a spherical sleeve, the deflection angle of the aircraft head realizes the accurate following according to input signals, the influence of the hinge moment is overcome, and the aircraft head is driven to fast deflect.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Transmission line transient state high frequency component processing differential motion pilot protection method

The invention provides an electric power transmission line transient state protection scheme. Due to the fact that a transmission line produces a great quantity of transient state high frequency signals under a short trouble condition, stray capacitance exists in a bus over the ground, fault currents or voltage high frequency components strikingly decrease when the fault currents or the voltage high frequency components pass through the bus, and a valve, detected on the inner side of a bus of a protected line, of the same fault high frequency component is always greater than or richer than a value detected on the outer side. The principle is used, currents or voltage on the inner side and the outer side of the bus at two ends of the protected line are acquired, high frequency components of the currents or the voltage are extracted and processed appropriately, differences of transient state high frequency component processing capacity on the inner side and the outer side of the bus, such as an energy difference or an entropy difference or a complexity difference or specificity difference or module maximum value difference or other processing capacity differences are calculated, area-in and area-out faults are judged and distinguished based on differences of the transient state high frequency component processing capacity at two ends of the transmission line, and thus protection of the line is achieved. The protection principle is simple, has an absolute selectivity, is stable and reliable in performance, is quick in motion, and can protect the total length of the line.
Owner:郭振威

Single-phase grounding fault line selection method applied to flexible grounding system

InactiveCN110488155AImprove the accuracy of line selectionReduce misjudgmentFault location by conductor typesCapacitanceCorrelation coefficient
The invention discloses a single-phase grounding fault line selection method applied to a flexible grounding system. The method comprises three steps of fault time positioning, transient characteristic signal extraction and faulty feeder discrimination, and specifically comprises the steps of 1) carrying out wavelet packet decomposition on a zero sequence voltage signal of a neutral point, and taking a time point corresponding to a modulus maximum point as the actual fault time; 2) selecting feeder zero-sequence current signals of 1 / 4 and 3 / 4 periods before and after the actual fault time, carrying out wavelet packet decomposition and reconstruction, and extracting transient characteristic waveforms; and 3) calculating a comprehensive gray T-shaped correlation coefficient of the transientcharacteristic waveform of each feeder, and comparing the comprehensive gray T-shaped correlation coefficient with a threshold value to determine a faulty feeder. According to the method, the relevance of the dynamic change trend of the overhead line and the dynamic change trend of the cable is effectively reflected, the misjudgment caused by the difference between the capacitance values of the cable and the overhead line to the ground is reduced, the requirements of a flexible grounding system for the rapidity and accuracy of line selection are met, and the method has feasibility and practical value.
Owner:LIYANG RES INST OF SOUTHEAST UNIV +1

Direct-current converter high-frequency impedance modeling method

InactiveCN110535348AAccurate Response Impedance CharacterizationNot affected by the operating stateElectric power transfer ac networkAc-dc conversionHarmonicEngineering
The invention discloses a direct-current converter high-frequency impedance modeling method. The method comprises the steps of determining various harmonic paths in a DC / DC converter and a modular multilevel converter, wherein the DC / DC converter and the modular multilevel converter belong to a direct current converter; carrying out equivalence and simplification on high-frequency harmonic paths in the DC / DC converter and the modular multilevel converter according to an actual impedance parameter to obtain a constant high-frequency harmonic path; and based on the constant high-frequency harmonic path, calculating a high-frequency impedance model of each DC / DC converter and the modular multilevel converter. By using the method, on the basis of analyzing the DC / DC converter and an MMC harmonic path, reasonable equivalence and simplification are performed according to an element parameter characteristic, and a high-frequency impedance model of the converter is established. The model is not influenced by a converter control strategy and a system operation state, can accurately reflect the high-frequency impedance characteristic of the system under direct-current protection logic that the converter is not shut, and has an important reference value for configuration of direct-current protection.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

Control time sequence of cascade full-bridge direct-current circuit breaker control system

The invention discloses a control time sequence of a cascade full-bridge direct-current circuit breaker control system. A time sequence logic and control algorithm for control and fault monitoring can be provided according to the functional requirement of the cascade full-bridge circuit breaker and according to the control requirement of the circuit breaker and the coordination relation of all parts of the circuit breaker. By adopting the control time sequence logic, the short-circuit fault on the direct-current circuit can be rapidly responded, the action of the circuit breaker is controlled, and the requirement for rapidness of the direct-current circuit breaker can be met; main tasks of the cascade full-bridge high-voltage direct-current circuit breaker control protection device are summarized, the time sequence of each task is designed according to the control requirement of the cascade full-bridge direct-current circuit breaker, all tasks are connected with one another, and the control of the circuit breaker is completed; according to the control time sequence of the cascade full-bridge direct-current circuit breaker, the fault of each part of the circuit breaker can be discovered in a short time, and an appropriate measures can be taken.
Owner:STATE GRID CORP OF CHINA +2

Drive device for head deflection of bevel gear push-rod type aircraft

The invention discloses a drive device for head deflection of a bevel gear push-rod type aircraft. The drive device for head deflection of the bevel gear push-rod type aircraft comprises a supporting mechanism, power mechanisms, a bevel gear steering mechanism, a connection rod transmission mechanism, a head and rotation connection arm mechanism and an aircraft head body connection mechanism. The power mechanism, the bevel gear steering mechanism and the aircraft head body connection mechanism are fixed to a base of the supporting mechanism. The power mechanisms are arranged along the axis of a machine body. The connection rod transmission mechanism pushes the head and rotation connection arm mechanism to rotate around a ball head in a spherical sleeve of the supporting mechanism. When the head shell of the aircraft begins to conduct deflection, an aircraft computer sends out a signal, and the power mechanisms receive control signals and drive the bevel gear steering mechanism to rotate. The bevel gear steering mechanism converts the rotation movement to linear movement of the connection rod transmission mechanism. The head and rotation connection arm mechanism rotates around the spherical sleeve so as to achieve head deflection of the aircraft. The deflection drive device is simple and compact in structure, and is especially suitable for small aircrafts.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Filament constant-tension control method based on optimized BP neural network

The invention discloses a filament constant-tension control method based on an optimized BP neural network. The method comprises the steps of: building a filament constant-tension control hardware system based on the optimized BP neural network; determining a BP neural network structure, input sample data and an expected output value of the neural network; initializing populations of weights and threshold values, and calculating the fitness values of the populations; performing selection , crossing and mutation operation on the initial value and threshold value of the neural network; performing winning and elimination according to fitness values obtained after genetic operation; describing a weight matrix and a threshold value matrix in the optimized BP neural network structure into a chromosome string; and adopting judgment on whether a system reaches required precision or not as an end condition, under the condition that the system reaches the required precision, ending the algorithm, and otherwise, returning to continue the operation. With the method adopted, the problem that in the prior art, tension is not stable in the wool sprayed tape yarn is solved.
Owner:XI'AN POLYTECHNIC UNIVERSITY +1

Control method of LCL grid-connected inverter based on PI and repetitive control strategy

InactiveCN109617115ASimplified Coordinate TransformationSimplify the decoupling calculation processSingle network parallel feeding arrangementsPhotovoltaic energy generationGrid connected inverterTotal harmonic distortion
The invention provides a control method of an LCL grid-connected inverter based on a PI and repetitive control strategy. The control method comprises the step of adjusting output of the LCL grid-connected inverter by applying a composite controller connected in parallel by PI control and repetitive control in a two-phase rest coordinate system. The dynamic performance of a system can be met; a steady state performance requirement of the system can be met; coordinate transformation and decouple calculation are simplified; the inhibiting capacity of a photovoltaic inverter for harmonic output isimproved; and a total harmonic distortion rate of grid-connected current of the inverter is reduced.
Owner:HUNAN UNIV OF TECH

Servo control system of four-axis full-automatic tin soldering robot

The invention discloses a servo control system of a four-axis full-automatic tin soldering robot. The servo control system comprises a control module, a first motor, five motors, an action module, a tin discharging module and a temperature sensor, wherein the control module comprises a digital signal processing chip and a field programmable gate array chip, the digital signal processing chip is connected with a spot soldering position on the action module through the temperature sensor, the field programmable gate array chip generates a pulse width modulated wave signal to be transmitted to the five motors, four electrodes are respectively connected with the action module, and the fifth motor is connected with the tin discharging module. According to the servo control system of the four-axis full-automatic tin soldering robot, the processing speed of the servo control system is greatly increased through the control module based on the digital signal processing chip and the field programmable gate array chip, the rapidness requirement of the tin soldering system can be well met, the design is simple, the development period is shortened, the program runaway can be effectively prevented, and the interference resistance is greatly enhanced.
Owner:SUZHOU INDAL PARK INSTITUE OF VOCATIONAL TECH

Multi-closed loop method introducing torque correction into high-precision tracking system

The invention provides a multi-closed loop method introducing torque correction into high-precision tracking system, wherein the high-precision tracking system has higher requirement on the rapidity and the stability of rotation speed and torque. The conventional current closed loop can not restrain torque fluctuation caused by the distortion of a motor magnetic field; and the bandwidth of the torque closed loop is limited, so that rapid torque response can not be provided. Aiming at the permanent magnet synchronous motor-driven high-precision tracking system, the invention provides a multi-closed loop control mode replacing the conventional current closed loop-speed closed loop multi-closed loop control mode with the current closed loop-speed closed loop multi-closed loop control mode in which the torque correction is introduced, so that the high-speed bandwidth torque response can be provided, the torque fluctuation caused by the harmonic wave of the motor magnetic field can be restrained, and the torque correction parameter can be estimated by a torque estimator in real time.
Owner:INST OF OPTICS & ELECTRONICS - CHINESE ACAD OF SCI

High-response current control method of alternating-current servo system

The invention belongs to the current control technology field, and discloses a high-response current control method of an alternating current servo system and a control system. The method is characterized by reducing a voltage output lag by using a mode of PWM duty ratio double refreshing in a current control period; adopting a current prediction control algorithm, processing a current sampled atthe moment through the prediction control algorithm to obtain a predicted voltage at the next moment, taking the predicted voltage as output of a current loop, and offsetting sampling delay; and usingcomplex vector decoupling control for dq-axis voltage coupling. A simulation test shows that compared with a conventional PI regulator, the method of the invention has a better current response characteristic. In the invention, current loop performance is improved, a response is increased, and a rapidity requirement can be well satisfied in some high-response application occasions; and in obtained decoupled current prediction, a current loop bandwidth is the widest, and the response is the fastest.
Owner:HUBEI UNIV OF TECH

Suspected micro-calcification point region automatic positioning method based on discriminant deep belief network

The invention discloses a suspected micro-calcification point region automatic positioning method based on a discriminant deep belief network. The method comprises the following steps: 1) mammary gland X-ray image preprocessing: segmenting and enhancing a mammary gland region; 2) sample acquisition and preprocessing: segmenting the enhanced mammary gland image to obtain a sub-block image set for model training, and performing noise reduction and background removal processing on sub-blocks; 3) sub-block feature extraction and classification: constructing a discriminant deep belief network (DDBNs), training and finely adjusting a DDBNs model, and completing feature extraction and automatic classification of mammary gland sub-blocks; and 4) micro-calcification point region detection: inputting a mammary gland X-ray image to be detected, performing a series of preprocessing on the image, performing classification judgment on the sub-blocks by applying the trained optimal model, and markingsuspicious micro-calcification point regions according to a judgment result. According to the method, automatic detection and positioning of the suspicious lesion area can be completed, the false positive rate is effectively reduced while the high detection rate is obtained, and the detected calcification point area and the expert marking area have high consistency.
Owner:HARBIN UNIV OF SCI & TECH

Automatic power trend recognition method

The invention relates to an automatic power trend recognition method. The method comprises the steps of receiving original data of active power by a server in real time; pre-processing the original data; recognizing an oscillation state of the active power; and recognizing an active power trend. With technical scheme provided by the invention, automatic recognition on the trend and the oscillation of the active power is achieved by employing a high-frequency data smoothing technology and combining experience of people during the long-term calculation process and a special calculation method so that the purposes of helping signal trend and oscillation recognition of a power system and guiding actual running are achieved.
Owner:STATE GRID CORP OF CHINA +3

Interface circuit of fiber-optic gyroscope combination

ActiveCN106979790AMiniaturizationRealize offline uploadMeasurement devicesFiberTransceiver
The invention discloses an interface circuit of a fiber-optic gyroscope combination. The interface circuit comprises an FPGA(Field Programmable Gate Array), a first serial transceiver circuit, a sequential electrifying control circuit, an I / V conversion amplifying circuit, a second serial transceiver circuit, and a PROM (Programmable Read-Only Memory). The FPGA is connected with an upper computer. An input end of the first serial transceiver circuit is connected with the fiber-optic gyroscope combination, and an output end of the first serial transceiver circuit is connected with the FPGA. The sequential electrifying control circuit is connected with the FPGA and used for charging the FPGA in a time sharing way. An input end of the I / V conversion amplifying circuit is connected with a meter combination while an output end thereof is connected with an input end of an A / D conversion circuit. An output end of the A / D conversion circuit is connected with the FPGA. One end of the second serial transceiver circuit is connected with the FPGA while the other end thereof is connected with a superior system. The second serial transceiver circuit is used for receiving information, about angular velocity and acceleration of the fiber-optic gyroscope combination and the meter combination, output from the FPGA, and then outputting the information to the superior system. The PROM is used for saving non-volatile soft programs for signal processing. The interface circuit has the advantages of simple structure and quick start of electrifying.
Owner:SHANGHAI AEROSPACE CONTROL TECH INST
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