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101 results about "Fault resistance" patented technology

Power grid fault early warning system based on machine learning and related device

The invention relates to the technical field of data processing, and discloses a power grid fault early warning system based on machine learning and a related device, and the system is characterized in that an initial monitoring module identifies and identifies abnormal data points through monitoring the voltage, current and load of a power grid, and obtains an abnormal mode identification result; the load fluctuation analysis module positions the abnormal node according to the abnormal mode identification result to obtain abnormal node positioning information; the trend analysis and prediction module evaluates and predicts fault nodes and time according to the abnormal node positioning information to obtain a risk prediction result; the strategy formulation and response module formulates an operation instruction based on the risk prediction result to obtain a fault prevention measure; the fault simulation and test module performs virtual fault simulation by adopting fault prevention measures, and performs iterative optimization on a strategy to obtain a test evaluation result; and the fault early warning and optimization module optimizes a fault prevention strategy according to a test evaluation result, and a more accurate target fault early warning and a faster and more effective target response strategy can be obtained.
Owner:YUNNAN POWER GRID CO LTD LINCANG POWER SUPPLY BUREAU

New energy vehicle fault diagnosis and early warning system based on artificial intelligence

The invention discloses a new energy automobile fault diagnosis and early warning system based on artificial intelligence, and the system employs an advanced artificial intelligence technology, and is designed according to the fault diagnosis and early warning demands of a new energy automobile. By integrating a high-precision sensor and a real-time data acquisition module, the system can comprehensively monitor key performance parameters of the vehicle; by utilizing machine learning and deep learning algorithms, the system can automatically identify a fault mode, the diagnosis accuracy is improved, and the diagnosis time is shortened; meanwhile, based on a potential fault early warning function of big data analysis, vehicle data can be monitored in real time, potential faults can be found in advance, and measures can be taken in time to prevent the faults. The system also has a strong data processing capability, can process and analyze a large amount of vehicle data in real time, and provides powerful support for fault diagnosis and early warning. Generally speaking, the system can significantly improve the safety, reliability and maintenance efficiency of the new energy vehicle, reduce the maintenance cost of a vehicle owner, and improve the user experience.
Owner:高歌阳

Fault prevention method and device for power internet of things, and storage medium

The invention discloses a power Internet of Things fault prevention method and device and a storage medium, and the method comprises the steps: collecting the system state, system operation data and historical fault data of the power Internet of Things; inputting the system operation data and the historical fault data into a preset fault detection model to predict a fault event and a fault part when the electric power Internet of Things has a potential fault in the future, generating a preventive strategy report according to the fault event and the fault part, and optimizing the preventive strategy report according to the system state, the fault event and the fault part. And executing a repair operation according to the fault-tolerant strategy to obtain a repair result, if the repair result is repair failure, starting a standby system for the fault part, and optimizing the fault-tolerant strategy according to the repair result. According to the embodiment of the invention, the system operation data and the historical fault data are monitored and analyzed in real time through the electric power Internet of Things acquisition system, so that potential faults can be accurately predicted, a more comprehensive fault-tolerant strategy can be generated, and the accuracy of fault prediction is improved.
Owner:CHINA SOUTHERN POWER GRID COMPANY

Adaptive dynamic fusion method and system for heterogeneous data

The invention discloses a self-adaptive dynamic fusion method and system for heterogeneous data, and relates to the technical field of data processing, and the method comprises the steps: obtaining multi-source heterogeneous data of power equipment; detecting the state of the equipment and judging whether the equipment is in a fault mode, and recording a fault feature vector if the equipment is in the fault mode; inputting the fault feature vectors into a fault resistance evaluation model, evaluating the fault resistance of each data source, and outputting a plurality of fault resistance indexes; setting a preset fault resistance index, and dividing the data into a first type and a second type of heterogeneous data; and configuring fusion weights for the two types of data, performing data fusion according to the weights, and outputting a fusion result. The technical problem that in the prior art, the reliability difference of multi-source heterogeneous data cannot be effectively recognized in the power equipment fault state, and consequently the fault diagnosis accuracy is poor is solved, and the purposes of dynamically optimizing data fusion, improving the data reliability and improving the fault diagnosis accuracy are achieved through fault resistance evaluation and a self-adaptive sampling strategy. Therefore, the fault diagnosis accuracy is improved.
Owner:BAIYIN POWER SUPPLY COMPANY STATE GRID GANSU ELECTRIC POWER

Tracking and Prevention of Fault Injection Attempt Sequences using Thermal Memory

An integrated circuit (IC) includes a thermal memory device, a fault injection (FI) detector and a security control circuit. The thermal memory device includes (i) a thermal storage zone and (ii) a heating element configured to heat the thermal storage zone in response to write operations. The FI detector is configured to detect attempts to inject faults into the IC. The security control circuit is configured to perform a write operation to the thermal memory device in response to an attempt detected by the FI detector, to identify a sequence of the attempts that meets a density criterion, by reading the thermal memory device, and initiate a responsive action upon identifying the sequence.
Owner:NUVOTON

Power distribution cabinet power performance test system and method

The invention belongs to the technical field of power distribution cabinet inspection, and particularly relates to a power distribution cabinet power performance inspection system and method. According to the invention, by monitoring the power, current, temperature and other data of the power distribution cabinet in real time, abnormal electrical units can be found in time, faults can be prevented, stable operation of the power distribution cabinet can be ensured, the current and temperature weight values are comprehensively considered and combined with the power data, and the operation risk of the power distribution cabinet can be evaluated more comprehensively and accurately. Misjudgment caused by single data abnormity is avoided, potential electrical unit faults are found and positioned in advance, the overall fault occurrence probability is reduced, the maintenance cost and downtime are further reduced, an inspection report can be automatically generated, an alarm signal can be sent out, the workload of manual inspection is reduced, and the operation and maintenance efficiency is improved.
Owner:BEIJING HUADIAN MEIYI ELECTRIC TECH CO LTD

Method for predicting residual life of circuit breaker based on multiple parameters and dynamic correction

The invention relates to the technical field of circuit breaker state monitoring and fault prediction, in particular to a circuit breaker residual life prediction method based on multiple parameters and dynamic correction, which comprises the following steps: S1, constructing a data set, S2, constructing a multi-parameter fusion model, S3, constructing a circuit breaker residual life prediction model, S4, dynamically correcting a prediction result, and S5, referring to a circuit breaker state maintenance guide rule. S6, dividing a sample set for training, verifying and testing the model; and S7, performing model performance evaluation. According to the method, multiple parameters are fused, and the improved convolutional neural network and the dynamic correction mechanism are combined, so that the residual life prediction and the state accurate evaluation of the circuit breaker contact are realized, the operation safety of the circuit breaker is improved, operation and maintenance personnel are assisted to carry out maintenance in advance, and faults are effectively prevented.
Owner:BEIJING JOIN BRIGHT DIGITAL POWER TECH CO LTD

Power grid cable wiring path optimization method and device

The invention provides a power grid cable wiring path optimization method and device, and the method comprises the steps: carrying out the load analysis of geographical distribution data and power utilization data of a power grid system, and generating load region types and weight data corresponding to each region type; performing fault propagation risk assessment on power grid nodes in the power grid system according to the load area type and the weight data, and generating a cable capacity scheme according to a risk assessment result; generating a candidate path set through a multi-target balance mechanism and an adaptive path growth algorithm according to the load area type, the weight data and a cable capacity scheme; and carrying out toughness evaluation and optimization on the candidate path set under various preset simulation scene conditions to generate a power grid cable wiring scheme. According to the method, the power grid load distribution characteristic, the fault propagation risk and the system toughness are comprehensively considered, a cable wiring scheme which adapts to a complex load environment and has fault resistance can be generated, and the reliability and stability of a power grid system are remarkably improved.
Owner:STATE GRID HENAN ELECTRIC POWER COMPANY ZHENGZHOU POWER SUPPLY CO

Cable fault accurate positioning method and system based on electromagnetic time reversal correction

The invention relates to the technical field of cable line operation and maintenance, in particular to a cable fault accurate positioning method and system based on electromagnetic time reversal correction. And in combination with a reflection coefficient correction and local energy extraction method in a time inversion process, the problems that the fault traveling wave signal is attenuated and distorted under strong noise and high transition resistance, and the EMTR positioning effect is influenced by fault resistance are solved. Constructing a multi-scale evaluation system fusing time domain, frequency domain and wavelet domain features, and screening an optimal modal component; and constructing an actual fault resistor in a reverse phase of the EMTR to correct a reflection coefficient, and providing a criterion for positioning by using local energy at a first traveling wave to realize accurate positioning of a cable fault. According to the method, the ranging error can be effectively reduced under the conditions of high transition resistance, low signal-to-noise ratio and unknown fault resistance, and the robustness and engineering applicability of cable fault diagnosis are improved.
Owner:STATE GRID JIANGSU ELECTRIC POWER CO ZHENJIANG POWER SUPPLY CO +1

Fault type rock burst monitoring method, device and equipment and storage medium

The invention provides a fault type rock burst monitoring method, device and equipment and a storage medium, and the method comprises the steps: obtaining a target distance value between a fault and a coal seam advanced bearing pressure peak value position; obtaining a discrimination threshold value; wherein the discrimination threshold value is a distance value when the shear stress on the fault surface is equal to the shear strength of the fault surface; and monitoring the fault type rock burst based on the target distance value and the discrimination threshold value. According to the technical scheme of the invention, the method can achieve the quantification of the discrimination index for judging whether the fault-type rock burst occurs or not, and achieves the effective monitoring of the fault-type rock burst.
Owner:CHINA COAL RES INST

Transformer state prediction and adaptive control method based on digital twinning

The invention relates to the technical field of transformers, in particular to a transformer state prediction and adaptive control method based on digital twinning, which realizes real-time monitoring, fault prediction and adaptive control of a transformer by constructing a high-precision digital twinning model and a deep reinforcement learning algorithm. According to the method, finite element analysis software is used for modeling the physical structure of the transformer, a high-precision three-dimensional geometric model is generated, circuit simulation software is used for modeling electrical characteristics, a comprehensive digital twinborn model is formed, and the actual operation state of the transformer is comprehensively reflected. A fault module is added in the digital twin model, potential fault modes such as coil short circuit and iron core oversaturation are simulated, and faults are recognized and prevented in advance.
Owner:BEIAN TRANSFORMER (TIANJIN) LTD BY SHARE LTD

Analytic calculation method, system and equipment for transient voltage and current of power grid fault

The invention discloses an analytical calculation method, system and equipment for transient voltage and current of a power grid fault. The method comprises the following steps: constructing a fault resistance network matrix; calculating a voltage and current initial traveling wave at the fault point by adopting phase-mode transformation at least based on the fault resistance network matrix; constructing a fault component additional network; respectively calculating a first traveling wave refraction and reflection coefficient at a fault point and a second traveling wave refraction and reflection coefficient at a non-fault point in the fault component additional network; respectively acquiring all first traveling wave propagation paths and all second traveling wave propagation paths, and calculating the total propagation time and the total traveling wave refraction and reflection coefficient on each traveling wave propagation path at least based on the first traveling wave refraction and reflection coefficient and the second traveling wave refraction and reflection coefficient; and at least based on the total propagation time and the total traveling wave refraction and reflection coefficient, performing summation and superposition to obtain a fault transient voltage and current analytic expression. According to the method, a reliable theoretical basis can be provided for development of a relay protection and fault positioning technology based on high-frequency transient information.
Owner:STATE GRID ECONOMIC TECH RES INST CO LTD

Operation control method and device for network construction type energy storage power station under multiple time scales

The invention provides an operation control method and device for a network construction type energy storage power station under multiple time scales, and relates to the technical field of novel energy storage of a power system. An operation control method for a network-constructing energy storage power station under multiple time scales comprises the following steps: determining an operation state of a regional power grid; setting a control rule of the energy storage power station corresponding to the operation state; and executing the control rule to adjust the frequency of the regional power grid through the power of the energy storage power station. According to the embodiment of the invention, the operation economy of the power grid can be improved, and the fault resistance can be improved.
Owner:NR ELECTRIC CO LTD +1

District intelligent fusion terminal detection system supported by multiple protocols

The invention discloses a multi-protocol supported transformer area intelligent fusion terminal detection system, which is used for detecting a transformer area intelligent fusion terminal and a functional module thereof, and is characterized by comprising front-end processor software connected with a standard source cabinet and a test tool cabinet through a communication service unit, the standard source cabinet is connected with the test tool cabinet through a two-way communication line; the standard source cabinet comprises a program control power source, a three-phase standard meter, a standard clock source and a positioning system; the test tool cabinet comprises a communication interface test unit, a complete machine power consumption test unit, a loop inspection test unit, a station test control unit and a station connection unit. The front-end processor software deploys the standard source cabinet and the test tool cabinet through the communication service unit to realize power supply adaptability detection, grounding fault resistance capability detection, power consumption detection, alternating current analog quantity experiment detection, state quantity experiment detection and data acquisition processing experiment detection of the SCU to be detected; loop state inspection experiment detection and clock and positioning experiment detection are carried out.
Owner:国网新疆电力有限公司营销服务中心

Data writing method and electronic equipment

The invention discloses a data writing method and electronic equipment, and relates to the technical field of storage, the method comprises the steps that after writing data sent by a host is received, first detection information is sent to a second node, and the writing data is the writing data sent to a first node after the host determines that the first node joins a cluster; receiving a first detection result sent by the second node; when it is determined that the first detection result is that the second node does not write all data in the cache of the second node into the rear-end hard disk, whether the node state of the second node is an online state or not is determined; and when the node state of the second node is determined to be an online state, forwarding the write data to the second node, so that the second node writes the write data into a rear-end hard disk. According to the method and the device, the problem that the redundancy capability and the anti-fault capability of the cluster are poor due to the fact that the node leaving the cluster cannot join the cluster as soon as possible after recovery and cannot perform data processing is solved.
Owner:INSPUR SUZHOU INTELLIGENT TECH CO LTD

Trigger type probe fault detection method and system

The invention provides a trigger-type probe fault detection method and system, and relates to the technical field of fault detection, and the method comprises the steps: obtaining the information of a built-in sensor of a to-be-detected trigger-type probe, configuring a test circuit and a test scene, connecting the probe to the test circuit through an interface of the probe, executing the fastening verification of a connection structure, and when the verification is passed, carrying out the fault detection of the to-be-detected trigger-type probe. Controlling the test circuit according to the first test scene and the second test scene, receiving an output signal of the probe, generating a first test signal sequence and a second test signal sequence, performing fault analysis by combining the first test signal sequence and the second test signal sequence, and generating a fault detection result. The technical effects that the accuracy of fault detection is improved, early warning is carried out in advance, and faults are rapidly and accurately positioned are achieved.
Owner:SHENZHEN ZHENGYUANXIANG IND INTELLIGENCE CO LTD

Circuit breaker contact mechanical property state detection system

The invention relates to the technical field of sensors, and discloses a circuit breaker contact mechanical property state detection system which comprises a multi-sensor deployment module, an original data acquisition module, an original data preprocessing module, a contact pressure monitoring module, a data error calculation module, a data error analysis and adjustment module and a contact pressure comprehensive judgment module. The early warning information output module is used for performing error analysis and calculation on data acquired by the sensors to obtain error indexes of the sensors, performing parameter adjustment on the sensors which do not accord with a preset threshold value, and outputting early warning information when all the error indexes accord with the preset threshold value. According to the error index of each sensor and the stress deformation index of each pressure sensor calculated through the pressure monitoring mathematical model, a comprehensive judgment model is established to calculate the contact pressure stability index, and comprehensive judgment is performed according to the contact pressure stability index, so that the change of the contact pressure of the contact can be found in time; and faults are prevented.
Owner:STATE GRID SICHUAN ELECTRIC POWER CORP ELECTRIC POWER RES INST

Permanent magnet generator fault monitoring method and device, electronic equipment and storage medium

The invention provides a permanent magnet generator fault monitoring method and device, electronic equipment and a storage medium, and relates to the technical field of motor fault detection, and the method comprises the steps: obtaining the historical operation data of a target permanent magnet generator; according to the historical operation data, establishing a motor model of the target permanent magnet generator in each working condition state; determining time domain features and frequency domain features of the target permanent magnet generator in each working condition state based on the motor model; and performing fault monitoring on the target permanent magnet generator based on the time domain feature and the frequency domain feature. Therefore, compared with the prior art that data acquisition is carried out through installation of a sensor, high-frequency voltage is injected through an inverter, then corresponding high-frequency inductance is calculated, and then identification analysis of specific harmonic waves is completed, the scheme in the invention can realize continuous monitoring and diagnosis, fault occurrence can be effectively prevented, and the fault diagnosis accuracy is improved. The dependence on sensors and monitoring conditions is small, and the operation efficiency and economic benefits of the whole wind power plant can be remarkably improved.
Owner:CHINA UNITED GAS TURBINE TECH CO LTD

High-resistance grounding fault detection method and device, equipment and storage medium

The invention provides a high-resistance grounding fault detection method, device and equipment and a storage medium, and the method comprises the steps: collecting a three-phase current and voltage signal of a small-resistance grounding system, and carrying out the processing of the three-phase current and voltage signal to obtain a zero-sequence current and a zero-sequence voltage; when the zero-sequence voltage energy characteristic meets a preset condition, calculating fault grounding resistance according to the zero-sequence current, the zero-sequence voltage and system electrical parameters; calculating a transient zero-sequence current characteristic value and a steady-state zero-sequence voltage characteristic value according to the fault grounding resistance, and comparing the characteristic values with a threshold value; and when the two characteristic values are both smaller than the corresponding threshold values, determining that the fault is a high-resistance grounding fault. According to the method, the fault grounding resistance is calculated, the transient state and steady state characteristic criteria are deduced based on the resistance, and the detection basis is converted from direct measurement of the fault current to analysis of the fault resistance characteristics, so that accurate identification of the low-current high-resistance grounding fault which is difficult to detect by a traditional method is realized.
Owner:STATE GRID HENAN ELECTRIC POWER COMPANY ZHENGZHOU POWER SUPPLY CO

Low-voltage and low-frequency load shedding function test method and test device

The invention relates to the technical field of electric power detection, and provides a low-voltage and low-frequency load shedding function test method and a test device, in the on-site real-model test process, the test method and the test device are hung on a grid along with an FTU, the voltage and frequency change of the power grid and the action of the FTU are recorded in real time, a broken line graph is generated through upper computer software, and the action process of on-site low-voltage and low-frequency detection is displayed. Whether the device correctly executes the low-voltage and low-frequency load shedding action or not is visually observed, and the method has high practical significance (fault prevention), asset configuration optimization (service life prolonging) and final service for efficient, reliable and economical operation of a power grid.
Owner:SHANDONG ELECTRICAL ENG & EQUIP GRP XINNENG TECH CO LTD

Single-ended distributed parameter fault location method for ultra-high voltage transmission line

This invention relates to a single-end distributed parameter fault location method for ultra-high voltage (UHV) transmission lines, comprising: acquiring the line parameters of the UHV transmission line under test and determining whether a fault has occurred; acquiring the three-line voltage vector and three-phase current vector of the faulty end of the transmission line, establishing a distributed parameter model of the transmission line, and dividing the distributed parameter model of the transmission line into a fault-side segment model, a fault-opposite-side segment model, and a fault branch model according to the fault region; employing a single-end phasor domain centralized parameter fault location method to solve for the initial values ​​of the fault location and fault resistance; based on the fault-opposite-side segment model, constructing a fault location equation with the fault location and fault resistance as variables, and iteratively solving for the fault location and fault resistance as an optimization problem, as the fault location result. Compared with the prior art, this invention significantly improves the fault location accuracy of UHV long-distance transmission lines.
Owner:EAST CHINA BRANCH OF STATE GRID CORP +2

Self-detection ignition system for aero-engine

The invention relates to the technical field of aero-engine fault detection, in particular to a self-detection ignition system for an aero-engine. The invention provides a self-detection ignition system which comprises an ignition exciter, an ignition cable and an ignition electric nozzle. The ignition exciter at least comprises a self-detection module and a fault resistance module. The fault resistor module forms a feedback resistor loop by a plurality of resistors with different resistance values and is used for feeding back a fault state or a normal working state of the ignition exciter; the self-detection module selects a corresponding resistor in the fault resistor module according to a detection result of internal fault information of the ignition exciter to be connected to the feedback resistor loop; and the engine electronic controller identifies and determines a corresponding fault mode according to an acquisition result of the resistance value of the feedback resistance loop. According to the method, the ignition failure reason can be rapidly judged when ignition fails, specific fault components can be accurately positioned when the ignition system breaks down, and the troubleshooting efficiency is improved.
Owner:AECC COMML AIRCRAFT ENGINE CO LTD

Fault position identification method for power distribution system based on artificial intelligence ammeter data visualization

According to the artificial intelligence ammeter data visualization-based power distribution system fault position identification method provided by the invention, three basic learners, namely a random forest, a K-proximity algorithm and an artificial neural network, are combined, and an integration method of combining a plurality of different machine learning models into a prediction model can be adapted to different scenes, so that the accuracy of the prediction model is improved. For example, noise and data loss, fault resistance change, load or power distribution feeder structure change and the like can be realized. An integrated voting classifier is developed, and a random forest, kNN and an artificial neural network model are utilized to classify fault types and identify a limited number of data points of FL only using voltage measurement. According to the method, the key problem of insufficient multiple features is overcome, the fault position can be quickly identified, the method is not influenced by the initial angle of the fault and the resistance on the line, the anti-interference capability is high, the classification accuracy of multiple fault types is high, the detection precision is high, and the cost is not too high.
Owner:厦门工学院 +3

Low-voltage power distribution network high-resistance fault diagnosis method and system, medium and product

This invention discloses a method, system, medium, and product for diagnosing high-resistance faults in low-voltage distribution networks, belonging to the field of distribution network fault diagnosis technology. The method first constructs a comprehensive statistical model integrating amplitude and phase errors, time asynchrony errors, and communication packet loss to obtain measurement data with uncertainty; then, it extracts multi-dimensional node features and incorporates uncertainty to construct feature vectors; next, it constructs and trains a Bayesian graph convolutional neural network based on the power grid topology; finally, it outputs the fault probability and cognitive uncertainty, and combines dual thresholds to complete fault determination. This invention can effectively address the measurement uncertainty problem of smart meters, enhance the ability to identify weak features of high-resistance faults, reduce false alarms and missed alarms, and exhibits excellent robustness and diagnostic accuracy under different fault resistance and noise levels.
Owner:STATE GRID TIANJIN ELECTRIC POWER COMPANY +1

Power grid business data intelligent scheduling method based on multi-source data fusion

The invention relates to the field of power grid data scheduling, and discloses a power grid business data intelligent scheduling method based on multi-source data fusion, which comprises the following steps: fusing different business data of a power grid for risk assessment and fault probability assessment of the power grid and user loads, and combining a fault probability assessment result to obtain a power grid business data intelligent scheduling result; and carrying out load intelligent scheduling strategy construction and fault correction strategy construction on the user load and the power grid in the high-risk state. The system can accurately and actively identify the operation risk of the power grid, achieves the intelligent load transfer of main and distribution cooperation, can prevent faults in advance, achieves the quick response when the faults occur, effectively reduces the power-off time and range, guarantees the normal power demands of all walks of life and residents, and improves the power utilization efficiency. And meanwhile, unnecessary equipment overload and redundant operation can be avoided, the operation cost of the power grid is reduced, the service life of equipment is prolonged, and the operation economic benefit of the power grid is improved on the whole.
Owner:HUINING COUNTY POWER SUPPLY CO OF STATE GRID ANHUI ELECTRIC POWER CO LTD

A method for detecting short circuit fault in lithium ion battery

The application relates to the technical field of battery fault detection, in particular to a lithium ion battery internal short circuit fault detection method; in the method, first, constant voltage testing is carried out at a high SOC, and the short circuit resistance of the battery is calculated; whether the battery is short-circuited is judged according to the short circuit resistance data; if yes, then constant voltage testing is carried out at a low SOC, and the short circuit resistance is calculated; whether the battery is internally short-circuited or externally short-circuited is judged according to whether the short circuit resistance data is the same as the previous short circuit resistance data; if the battery is internally short-circuited and is a single-layer single-body structure battery, then the specific internal short circuit type is judged according to the two short circuit resistance data; through the fault detection method, the internal short circuit type of the fault resistance can be effectively judged.
Owner:BEIJING JIAOTONG UNIV

Fault-proof mechanism of thin-film capacitor braiding machine

The utility model relates to the technical field of capacitors, and discloses a fault-proof mechanism of a thin-film capacitor taping machine, which comprises a capacitor taping machine body and a box body, the rear side of the top end of the capacitor taping machine body is fixedly connected with a supporting disc, the inside of the left side of the supporting disc is fixedly connected with a motor, the driving end of the motor is fixedly connected with a limiting block, and the limiting block is fixedly connected with the box body. Sliding grooves are formed in the periphery of the left side of the limiting block, a supporting shaft is fixedly connected to the middle of the left side of the limiting block, a threaded strip is arranged at the left end of the exterior of the supporting shaft, the exterior of the threaded strip is in threaded connection with an adjusting ring, and a sleeve is slidably connected to the exterior of the supporting shaft. According to the utility model, mechanical faults caused by loosening or falling of the film winding drum can be prevented, the downtime of equipment is reduced, the production efficiency is improved, the tension of the film is adjusted while the external part of the film is cleaned, the equipment faults caused by impurities are effectively reduced, and the film is prevented from being torn or deformed in the processing process.
Owner:GUANGDONG CHENGXI ELECTRONIC TECHNOLOGY CO LTD

Co-excitation Wheatstone full-bridge circuit fault positioning method based on resistance measurement

The invention discloses a co-excitation Wheatstone full-bridge circuit fault positioning method based on resistance measurement, and belongs to the technical field of flight load spectrum testing. The system comprises a graphical interface module, a measurement data management module, a circuit topology storage module, an admittance matrix calculation module, a fault diagnosis engine module, a result display module and a file management module. The implementation method comprises the following steps: constructing a topological structure of a co-excitation Wheatstone full-bridge circuit, and defining nodes, resistors and a connection relation; inputting a resistance value among the eight fixed measurement points; generating possible fault resistance combination constraints; calculating a theoretical equivalent resistance value through an admittance matrix method; calculating the error between the theoretical value and the measured value; preferentially processing infinite constraints, and searching an optimal fault combination; and outputting a fault resistor positioning position and a diagnosis report. According to the invention, through automatic calculation and an intelligent optimization algorithm, rapid and accurate fault positioning is realized, and the maintenance cost and time of a flight load spectrum test system are substantially reduced.
Owner:BEIJING CHANGCHENG INST OF METROLOGY & MEASUREMENT AVIATION IND CORP OF CHINA

A non-blocking type DC fault ride-through control method for hybrid three-terminal DC power transmission system

The present application relates to the technical field of high-voltage direct current transmission, and particularly relates to a non-blocking type direct current fault ride-through control method for a hybrid three-terminal direct current transmission system; comprising the following steps: S1, performing sub-module proportioning design on the hybrid three-terminal direct current transmission system; S2, performing fault detection and triggering, and when the triggering condition is met, performing S3; S3, performing hierarchical fault control strategy, including mode conversion of the LCC converter station and non-blocking control of the FHMMC converter station; S4, when the fault clearing condition is met, resetting the mode conversion of the LCC converter station and stopping the regulation of the DC current size of the FHMMC converter station by the current converter inhibitor. The technical problems of poor fault resistance and operation economy of the LCC-FHMMC hybrid three-terminal direct current transmission system are solved.
Owner:POWERCHINA BEIJING ENG CORP