1214results about "Electrostatic field measurements" patented technology

The invention discloses a cable life dynamic evaluation system based on multi-physics field coupling, and particularly relates to the field of industrial automation and control systems, which comprises a multi-physics field sensing module, a coupling analysis engine module, a dynamic life evaluation module, a digital twin interaction module and an environmental interference suppression module, through a distributed optical fiber temperature sensor, a capacitive electric field sensor and a magnetostrictive stress sensor, temperature, electric field, magnetic field and mechanical stress data of a cable are collected in real time, multi-physical field characteristics and a cable defect database are matched in real time by using a cross-scale dynamic association algorithm, a damage state is evaluated, and the cable defect detection accuracy is improved. A time sequence neural network architecture is adopted to predict the remaining life, model self-correction is achieved through digital twin comparison, interference is suppressed in combination with an environment-physical field coupling compensation matrix, sensing and evaluation of the health state of the cable, life prediction and continuous optimization of the model are achieved, and the efficiency of cable life evaluation is improved.

The invention discloses a thunder and lightning early warning method based on atmospheric electric field networking monitoring. The method comprises the following steps: collecting multi-point electric field intensity data in a region in real time through a high-density electric field sensor network, and constructing an electric field intensity distribution matrix; for the constructed electric field intensity distribution matrix, space-time evolution characteristics of lightning activities are extracted, and lightning occurrence probability distribution is generated; acquiring temperature, humidity and air pressure parameters from multi-source meteorological data, performing data fusion with the generated thunder and lightning occurrence probability distribution, and constructing a comprehensive environment characteristic data set; and for the constructed comprehensive environment characteristic data set, calculating a comprehensive risk index, and if the index exceeds a preset thunder and lightning triggering threshold, etc. According to the lightning early warning method, the distribution matrix is constructed through the high-density electric field network, the spatial-temporal characteristics are extracted to generate the initial probability, and the physical rationality and the environment false alarm resistance of early risk identification are remarkably improved through fusion with the multi-source meteorological data.

The invention provides a multi-parameter MIMO (Multiple Input Multiple Output) aviation time-frequency detection system and method, which can be applied to the technical field of underground medium detection. The system comprises a flying platform, a transmitting subsystem, a receiving subsystem and a measurement and control subsystem, and the transmitting subsystem is configured to load a first current pulse into a transmitting coil through a first current transmitter to achieve primary electromagnetic field excitation and load a second current pulse into a compensation coil through a second current transmitter to achieve secondary electromagnetic field excitation. Compensation electromagnetic field excitation is realized; the receiving subsystem is configured to be used for sampling the first current pulse and the second current pulse and collecting secondary electromagnetic field response to obtain underground medium electrical information of the target detection area; and the measurement and control subsystem is configured to send a control instruction to the transmitting subsystem and the receiving subsystem according to a sampling result and set detection parameters and monitor the working state of the detection system, and the measurement and control subsystem adjusts the first current pulse and the second current pulse in real time.

The invention discloses a substation equipment health state monitoring system and method based on electric field intensity detection, and the system consists of an electric field intensity sensor, an image recognition module, an infrared imaging module, a data processing and analysis module, a wireless transmission module, an inspection robot, and a health state detection platform. The inspection robot collects electric field distribution, a visible light image and an infrared thermogram according to a preset line, appearance defects and temperature abnormity are analyzed through a convolutional neural network, and the data processing and analysis module can generate an electric field thermodynamic diagram and evaluate the equipment fault risk in real time through a deep learning algorithm. Abnormal information can be wirelessly transmitted to the health state detection platform, and an alarm is automatically given. Through multi-source data fusion and intelligent diagnosis, the system can effectively improve the inspection efficiency and accuracy, reduce manual errors, realize early detection of equipment cracks, corrosion, looseness and high-temperature overheating defects, and greatly improve the operation and maintenance efficiency and safety of a transformer substation.

The invention relates to the technical field of meteorological monitoring, in particular to a ring main unit lightning micrometeorological online monitoring system and method, and the system comprises a feature extraction module, a frequency spectrum detection module, a frequency band pool screening module, a path adjustment module and an interference avoidance module. The method comprises the following steps: collecting an electric field intensity extreme value sequence, calculating a change rate difference ratio, identifying thunder and lightning precursor characteristics, combining a frequency spectrum energy density map, analyzing an energy peak frequency band and a drop point of a frequency hopping signal, judging a thunder and lightning frequency signal concentration area, performing frequency spectrum interference filtering, and combining a dynamic time warping algorithm. The time deviation between a lightning stroke time point and frequency hopping scheduling is analyzed; a frequency hopping path is adjusted in real time; the response timeliness is improved; the difference value before and after electric field disturbance is monitored; and support is provided for monitoring stability and response adaptability of the thunder and lightning risk environment.

The invention discloses a Rydberg atom microwave measurement sensitivity improving method based on atom velocity selection, and relates to the field of Rydberg atom microwave measurement, and the method comprises the steps: moving the frequency of probe light to an energy level resonance transition position of cesium atoms from a ground state to an excited state, scanning the frequency of the coupled light within a Rydberg state energy level preset range, and observing an EIT signal; the frequency of the detection light is changed, the detuning amount of the detection light is selected to enable the EIT signal to reach the maximum, and the frequency of the detection light is locked to the frequency corresponding to the maximum position of the EIT signal; meanwhile, a local oscillation field signal generator in the Rydberg atomic microwave sensitivity measurement device is turned on, and corresponding EIT-AT splitting is generated; the frequency of the coupling light is locked to the coupling light laser frequency corresponding to the lowest point of EIT-AT splitting, and the Rydberg atom microwave measurement sensitivity reaches the maximum. The cesium atom speed is screened and controlled, and the signal-to-noise ratio of the measurement signal is improved, so that the measurement sensitivity is improved.

The invention discloses a rapid maintenance method for a distribution line, and relates to the technical field of electrical variable measurement, and the method comprises the steps: transmitting a multi-frequency electromagnetic wave to the distribution line through a multi-frequency electromagnetic wave detection device, receiving an echo signal, and extracting the electromagnetic characteristic data of the line; performing hierarchical analysis on the electromagnetic characteristic data to generate a fault preliminary report; based on the characteristics of the fault preliminary report and the echo signal, constructing a three-dimensional fault positioning map, and outputting fault positioning data; based on the repair suggestion report, utilizing an electric field to guide liquid metal to flow to the fault point, and performing filling and curing repair on the fault area; after repairing is completed, secondary detection is carried out on the repairing area and the adjacent area through multi-frequency electromagnetic waves, and the operation characteristics of the repairing point and the adjacent area are verified; according to the method, the electromagnetic characteristic data is extracted by using the echo signals, the three-dimensional fault positioning map is generated, the spatial position, geometric characteristics and material distribution of the fault point are accurately identified, and accurate support is provided for repair.

The invention discloses an electric field sensor-carrying unmanned aerial vehicle electricity testing platform and an electricity testing method, and relates to the technical field related to electricity testing, and the platform comprises an initialization unit which is used for calling electricity testing scene data and weather environment data according to an electricity testing task instruction to carry out the flight path planning of a multi-rotor unmanned aerial vehicle; the linkage acquisition unit is used for executing electric field signal acquisition; the alignment return unit is used for returning the mapped position attitude data and the electric field signal set to the edge calculation layer; a suppression unit for performing environmental interference suppression; and the discrimination unit is used for executing electricity verification correction discrimination of the electric field signal set and the mapped position attitude data and generating an electricity verification correction discrimination result. The technical problems that in the prior art, flight path planning is not scientific, electric field signal collection is prone to being interfered, data processing and judging efficiency is low, accuracy is poor, and electricity testing work efficiency and safety are poor are solved, and the technical effects of improving electric field signal processing accuracy, electricity testing work efficiency and safety are achieved.

The invention discloses a compensation method for a vibration capacitance type electrostatic sensor, and the method comprises the steps: detecting the temperature of an environment where the current electrostatic sensor is located, enabling a sensitive piece signal to serve as an input value after amplification and filtering, obtaining a sensor output value through a linear temperature compensation function, and achieving the low calculation amount and convenient integration; a temperature compensation method comprises the following steps: detecting the temperature of an environment where a current electrostatic sensor is located, loading a sinusoidal signal of a reference resonant frequency corresponding to the temperature to a first piezo-electric crystal, and detecting a feedback signal peak value of a second piezo-electric crystal, so that a tuning fork always vibrates at a natural vibration frequency, and the adaptability of the electrostatic sensor to the environment temperature is improved; according to the induction distance compensation method, the vertical distance between a current electrostatic sensor and the surface of a detected object is detected, a sensitive piece signal is amplified and filtered to serve as an input value, a sensor output value is obtained through a linear induction distance compensation function, the calculated amount is low, and integration is convenient.

The invention discloses a high-voltage cable lead seal defect monitoring system based on a resistance value, and relates to the field of cable monitoring, and the system comprises an instruction management module which is used for connecting a transmission power grid of a cable, obtaining the collection authority of power supply operation state data, and editing and sending control instructions of all function modules; the model construction module is used for collecting operation parameters of a plurality of lead sealing nodes and associated cables in a specified cable section in real time, integrating the operation parameters into power supply operation state data and constructing a lead sealing three-dimensional model; the trend monitoring module is used for inputting the real-time power supply operation state data of the current cable section into the lead sealing three-dimensional model and outputting the resistance change trend of a plurality of lead sealing nodes; by capturing and marking abnormal states of a plurality of nodes of a specified cable section, an efficient detection path is generated, the path planning efficiency is improved, the detection time is shortened, the maximum detection coverage is ensured, external environment interference is avoided, and crack propagation is predicted through a more accurate model.

The invention belongs to the field of data processing, and particularly relates to a high-voltage direct-current electric field intensity measuring method and a related device. In the device, an optical fiber direct-current electric field sensor at least comprises a signal processing unit, an optical fiber voltage sensing head, a fixed electrode and a rotating electrode. The method comprises the following steps: deploying a measuring device in a space to be measured; the rotating electrode is controlled to rotate at a constant speed, so that the center distance between the fixed electrode and the rotating electrode is periodically changed along with the rotating track; collecting an alternating current signal voltage generated by an alternating potential difference between the fixed electrode and the rotating electrode in a constant-speed rotating process through an optical fiber voltage sensing head; and performing numerical processing on the alternating current signal voltage through a signal processing unit to obtain a measured value of the high-voltage direct current electric field intensity, and optimizing the measured value in combination with a physical compensation model and a data driving compensation model. The method can realize the measurement of the high-voltage direct-current space electric field intensity, improve the measurement accuracy and expand the measurement range.

Disclosed is a direct control method and system for an internal potential of a bridge arm of a new energy grid-tied inverter (GTI), the control method including the following steps. Measured values are obtained by measuring a port voltage and a port current of a GTI, instantaneous active and reactive power values are calculated, and a phase angle and amplitude reference of an internal potential of a bridge arm are obtained to generate reference values thereof. The internal potential of the bridge arm is estimated, and an estimated value used as a feedback signal, after being compared with the reference values, is sent to an internal potential controller to obtain a modulating signal, which is sent to a pulse width modulation (PWM) module, realizing direct control of the internal potential of the bridge arm. In the present disclosure, the dynamic performance of the GTI is improved while improving power quality.

The invention discloses an error correction method and device for non-intrusive voltage differential measurement, a medium and a product, and relates to the technical field of voltage measurement, and the method is applied to a scene in which a differential electric field sensor array is arranged in a set range with a measured conductor as the center. Comprising the following steps: constructing an initial correction model based on a sensor distance and a measured conductor voltage; under the actual working condition, the initial correction model is processed through a least square method, and a correction model is obtained; when non-intrusive voltage differential measurement is carried out, the current measured conductor voltage and the sensor distance are obtained, and a correction coefficient is determined by adopting the correction model; and completing error correction of non-intrusive voltage differential measurement based on the correction coefficient. According to the invention, the complexity of an inversion algorithm and the special requirement on the spatial position of the sensor can be reduced.

The invention relates to the technical field of electrical measurement and power system monitoring, in particular to a cable insulation fault detection method. The method comprises the following steps: measuring an electric field signal and constructing an electric field distribution model in a cable to obtain a signal mapping result of a cable insulation state; the signal mapping result of the cable insulation state is mapped to a frequency domain, smoothing processing is carried out, multi-scale analysis is carried out on the signal after smoothing processing, fault features of the cable are extracted, the insulation state of the cable is quantified, the probability that the cable has an insulation fault is calculated, and a basis is provided for fault early warning and maintenance. The problems that most of traditional insulation fault detection methods depend on single electrical or spectral characteristic detection, so that detection information is incomplete; the stability is poor, and misjudgment or missed judgment is easily caused; in some methods, power failure or direct contact with a cable is needed for measurement, and continuous operation of the cable is affected. And complex electric field distribution and dynamic change thereof in the cable are difficult to accurately describe, and the fault development trend is difficult to predict.

The invention discloses a high-voltage cable state live detection method, which relates to the technical field of power detection, and is characterized in that a mathematical model of an electric field around a cable is established by using an electrostatic field equation in a Maxwell equation set, and electric field distribution between a cable insulation layer and a conductor is solved; high-frequency electromagnetic pulse signals are measured, and partial discharge detection in the insulating layer of the high-voltage cable is carried out according to a Paschen curve model; the temperature distribution change in the cable is simulated through a heat transfer equation, and the temperature distribution of the cable is monitored in real time by using a fiber bragg grating sensor; and correcting the electric field distribution and the partial discharge detection result based on the obtained temperature distribution of the cable. The partial discharge phenomenon in the cable insulation layer can be accurately identified and positioned, the insulation state of the cable can be monitored in real time, whether the discharge phenomenon exists or not can be rapidly judged, and therefore cable faults can be effectively prevented.

The invention provides a piezoelectric self-feedback excitation type miniature electric field sensor, an electric field detection method and a sensor, and is applied to the technical field of electric field sensors. The piezoelectric self-feedback excitation type miniature electric field sensor comprises a substrate used for supporting a vibration pickup reference structure, a piezoelectric driving structure, a mutual shielding electric field sensing structure and an elastic beam; the piezoelectric driving structure is used for enabling the piezoelectric driving structure to deform under the condition that driving voltage is applied to the piezoelectric driving structure so as to enable the elastic beam to generate vibration; the mutual shielding electric field induction structure is used for responding to the vibration of the elastic beam, and the mutual shielding electric field induction structure outputs an induction current signal in a differential form so as to suppress common-mode noise and detect the amplitude intensity of a to-be-detected electric field; and the vibration pickup reference structure is used for responding to the vibration of the elastic beam and outputting a reference current signal so as to adjust the magnitude of the driving voltage and enable the output sensitivity of the piezoelectric self-feedback excitation type miniature electric field sensor to be a preset value.

The invention discloses an electricity testing measuring device for power equipment. The invention relates to the field of space electric field measurement, and solves the problems of unsafety and low anti-interference capability of an existing electricity testing scheme. The electric field sensor collects the electric field intensity in a non-contact manner, and the distance sensor synchronously collects the detection distance, so that a conventional contact type electroscope does not need to contact equipment through a telescopic insulating rod. The signal processing circuit preprocesses electric field intensity information and distance information respectively to obtain effective analog signals representing the electric field to be measured, and the defect that a traditional non-contact plate electrode sensor induces stray electric fields indifferentially is overcome. Besides, the judgment control circuit judges the electrification state according to the preset electric field threshold value corresponding to the current distance analog signal instead of a single fixed threshold value of a traditional device instead of adopting a fixed threshold value, the electric field distribution characteristics of equipment with different voltage grades are adapted, manual intervention is not needed, and personal safety is guaranteed. And the occurrence rate of production accidents caused by abnormal electrification of equipment is reduced.

The invention discloses a zero-value insulator identification method and system based on multiple sensing modules. Firstly, space electric field probes are arranged in the space where two insulator strings are located, and the detection path of each probe is defined; then judging whether the insulator strings deflect or not by calculating the relative distance difference between the two insulator strings; if not, the space electric field effective value of each detection path at the same moment is collected, and whether a zero-value insulator exists or not is judged by calculating a symmetry judgment value; and if not, independently acquiring the effective value of the space electric field on the corresponding path of the insulator string at a set sampling interval, and judging whether the zero-value insulator exists or not by calculating the electric field deviation rate on each section of sampling path. The zero-value insulator in the insulator string under different postures can be accurately recognized, and the method has the advantages of being non-contact, high in real-time performance, capable of adapting to complex working conditions and the like.

The invention relates to the technical field of signal detection, in particular to a weak electric field signal detection method and system. According to the invention, complete information of frequency, amplitude and phase of a to-be-measured electric field signal is obtained at the same time in one measurement of the injection locking phonon laser, a to-be-measured laser amplitude spectrum and a to-be-measured laser phase spectrum are generated by the same injection locking phonon laser, and the amplitude signal and the phase signal which are measured and received must arrive at the same time. The two are simultaneous in time and have natural orthogonality in physics; therefore, compared with a traditional double-phase lock amplifier for analyzing two asynchronous signals to be measured received by two frequency mixers, the method for analyzing the laser amplitude spectrum and the laser phase spectrum to be measured to obtain the electric field information to be measured has the advantages that the accuracy is higher; the double-phase lock amplifier solves the technical problem of measurement errors caused by deviation of to-be-measured signals received by two frequency mixers in a traditional double-phase lock amplifier.

The invention provides a lightning protection monitoring method, system and device and a storage medium. The method comprises the following steps: detecting an electrostatic field signal of a target area; performing abrupt change reconstruction on the electrostatic field signal to obtain a plurality of abrupt change electric field values, and determining electric field energy based on waveform characteristics of the electrostatic field signal; a thundercloud discharge detection model is constructed through the electric field energy and all the abrupt change electric field values, and then a thunder early warning area is divided according to the discharge detection model; acquiring historical cloud-to-ground lightning distribution, fitting positioning features of the thundercloud in the thunder early warning area based on the historical cloud-to-ground lightning distribution, and fusing the positioning features and waveform features of the electrostatic field signals to obtain a moving trend of the thundercloud in the thunder early warning area; and establishing a lightning stroke risk coefficient of the target area through the moving trend, and performing lightning stroke early warning monitoring on the target area according to the lightning stroke risk coefficient. By adopting the scheme of the invention, short-time monitoring and early warning of thunder and lightning in a local area of a specific terrain can be realized.

The invention discloses a tower grounding grid multi-frequency composite wave electric field imaging and soil environment medium diagnosis method, which comprises the following steps of: generating a composite excitation signal through superposition of a low-frequency sine wave and a high-frequency CHIRP square wave, and collecting multi-dimensional data such as voltage / current response, soil temperature and humidity, electric field intensity and the like in combination with a distributed sensor array; separating signal features by using wavelet transform and extracting impedance information of a target frequency point; a multi-grid homotopy algorithm is adopted to realize grounding grid three-dimensional resistivity distribution reconstruction, corrosion spots and abnormal areas are marked, and high-precision positioning of underground conductors is completed through UWB radar or a capacitance detector; meanwhile, based on the information entropy maximization optimization frequency band combination, the grounding grid state is comprehensively evaluated in combination with a multi-parameter fusion model. The method has the non-contact patrol capability, the unmanned aerial vehicle carries equipment to scan the grounding grid, the detection efficiency and convenience are remarkably improved, and an efficient and accurate solution is provided for guaranteeing safe operation of the power grid.

The invention discloses a high-voltage switch cabinet fault monitoring and early warning system and method, and relates to the technical field of high-voltage switch cabinet fault monitoring. Comprising a detection acquisition module, a temperature monitoring module, a live monitoring module, a fault analysis module and an early warning execution module. In order to solve the problems of multiple challenges, insufficient data acquisition precision and comprehensiveness, lack of prediction capability for fault development trend and inaccurate fault abnormity judgment in the prior art, the invention utilizes the technical means of normalization processing, Fourier transform, correlation analysis and the like to accurately evaluate the monitoring data, so that the accuracy of the data acquisition is improved. Comprehensive judgment is performed in combination with multiple indexes, so that the problem of insufficient fault feature extraction and anomaly judgment capabilities in a traditional method is effectively solved; space positioning, time synchronization and correlation calculation technologies are introduced through the fault analysis module, abnormal points are locked quickly, and the change trend of potential risks is predicted in combination with trend analysis, so that the hidden danger identification and positioning efficiency of the system is improved.

The invention discloses an MEMS and TMR fused overhead line lightweight monitoring device, and the device comprises an annular shielding cover which sleeves a to-be-detected overhead conductor and is coaxial with the to-be-detected overhead conductor, and the side wall of the annular shielding cover is provided with a through hole; the sensing unit comprises at least two MEMS electric field sensors and at least two TMR magnetic field sensors and is used for detecting an electric field and a magnetic field generated by the overhead conductor to be detected; the analysis processing unit is used for receiving, processing and transmitting the signal generated by the sensing unit; and the power supply unit is arranged in the annular shielding cover and is electrically connected with the sensing unit and the analysis processing unit. The beneficial effect of the invention is that the coupling crosstalk phenomenon generated by an external electromagnetic field can be effectively suppressed. Moreover, the monitoring device is small in size, is convenient to install and deploy in a complex line environment, provides a stable hardware basis for precise inversion of voltage and current through structural cooperation, and provides reliable support for intelligent monitoring of an overhead line.

The invention discloses a miniature microwave electric field intensity measurement method based on Rydberg atoms, and belongs to the field of microwave electric field measurement. The implementation method comprises the following steps: scanning through an alkali metal atom gas chamber by using first probe light, scanning through the alkali metal atom gas chamber by using first coupling light, radiating a microwave electric field to be detected to the alkali metal atom gas chamber, obtaining an EIT-AT split spectrum, and obtaining the microwave electric field to be detected; if the EIT-AT splitting spacing is not available, a local oscillation microwave electric field can be radiated to the alkali metal atom gas chamber at the same time, a microwave electric field to be measured is obtained through an atom superheterodyne method, and rapid measurement of the intensity of the miniaturized microwave electric field based on Rydberg atoms is achieved. The device for realizing the method comprises a first laser, a first dichroscope, an alkali metal atom gas chamber, a second laser, a second dichroscope, a photoelectric detector, a first standard gain horn antenna and a second standard gain horn antenna. Frequency locking does not need to be carried out on detection light and coupling light, light path devices can be reduced, and the application range is wide.

The invention relates to the technical field of electrical equipment monitoring, and discloses an insulation state on-line monitoring system for electrical equipment of a high-voltage transformer substation, and the system comprises a data collection module which is used for collecting electric field intensity, partial discharge signals and temperature and humidity data in real time, and transmitting the data to each module through a transmission unit; the multi-physics field coupling modeling module is used for calculating electric field distribution and temperature field distribution in the equipment through electric field simulation and temperature field simulation according to the electric field intensity and temperature and humidity data; and a dielectric loss and partial discharge linkage analysis module. According to the method, electric field intensity, partial discharge signals and temperature and humidity data are comprehensively analyzed by combining multi-physics field coupling modeling and intelligent reasoning technologies, accurate equipment insulation state evaluation and fault prediction are achieved, meanwhile, an electric field-temperature field coupling analysis technology is adopted, partial discharge and a heat effect are combined, and the reliability of equipment insulation state evaluation and fault prediction is improved. And an overheating area and an insulation problem in the equipment can be accurately identified.

The invention relates to the field of electric field quantum measurement, in particular to a low-frequency electric field measurement method and a three-photon Rydberg system. The low-frequency electric field measurement method comprises the following steps: moving an atom gas chamber containing cesium atoms to a low-frequency electric field to be measured; cesium atoms are driven by probe light to transition from a ground state 6S1 / 2 to an excited state 6P1 / 2; driving cesium atoms to jump from an excited state 6P1 / 2 to an excited state 9S1 / 2 through decoration light; driving the cesium atoms to transition from an excited state 9S1 / 2 to a higher Rydberg state nP3 / 2 through coupled light to obtain Rydberg atoms; a photoelectric detector is adopted to detect the absorption condition of the detection light; based on the absorption condition, an oscilloscope is adopted to observe EIT spectrum change; based on the EIT spectrum change, obtaining a spectrum frequency shift amount; and the electric field intensity of the low-frequency electric field to be measured is calculated through the spectral frequency shift amount and the polarizability of the Rydberg atoms, so that the shielding problem of the atomic air chamber to the low-frequency electric field can be reduced, the spectral line width is narrower, and the electric field measurement resolution is greatly improved.

The invention discloses a power frequency phase adaptive acquisition device, and relates to the technical field of electric power signal measurement, the device acquires electric field data at a gap through an electric field sensor integrated on an edge shell, calculates electric field intensity fluctuation, and generates interference diagnosis information in combination with a preset interference determination threshold value; when the interference diagnosis information shows that effective interference exists, the electric field intensity variable quantity is calculated, a mapping model is established based on a proportionality coefficient obtained through an experiment so as to obtain zero crossing point offset, and the sampling trigger moment of a zero crossing point detection module is corrected; the clock synchronization module calculates a phase difference by taking the corrected trigger moment as a reference, dynamically adjusts a calibration frequency by combining a phase difference threshold value, and outputs a synchronized system clock signal; and the control system takes the synchronized system clock signal as a trigger signal, collects power frequency phase data according to a power frequency period, and stores the power frequency phase data to a database through a transmission unit, thereby realizing high-precision power frequency phase collection.

The invention provides a novel environment-friendly insulating gas surface flashover characteristic evaluation method based on surface charge on-line measurement, which comprises an electric field measurement system based on an electric field induced second harmonic effect (EFISH), a coupling high-voltage surface flashover experiment system, and an evolutionary process of an electric field in a process of applying high voltage to surface flashover, the evolutionary process of charge distribution is obtained based on the electrostatic field source relation, the starting moment of surface flashover is determined by measuring sound, light and electromagnetic signals in the surface flashover process, and the starting area of the surface flashover is observed through a high-speed camera; and associating the relationship between the charge and the surface flashover, and quantitatively explaining the induction effect of the charge on the flashover.

The invention discloses a method and system for directly controlling the internal potential of a bridge arm of a new energy grid-connected inverter, belonging to the technical field of grid-connected inverter control. The control method comprises the following steps: obtaining measured values ​​by measuring the port voltage and current of the grid-connected inverter, and calculating instantaneous active and reactive values; obtaining the phase angle reference and amplitude reference of the internal potential of the bridge arm of the grid-connected inverter respectively, and then generating the internal potential reference of the bridge arm; at the same time, estimating the internal potential of the bridge arm of the grid-connected inverter based on the port voltage and current measured values ​​and the grid-connected inverter model by using an observer; finally, using the estimated internal potential as a feedback signal of the closed-loop feedback control of the internal potential, comparing it with the generated internal potential reference of the bridge arm, and sending it to the internal potential controller, thereby obtaining a modulation signal and sending it to the PWM module, so as to realize direct control of the internal potential of the bridge arm of the grid-connected inverter; compared with the existing control method of the grid-connected inverter, the method of the invention improves the dynamic performance of the grid-connected inverter and improves the power quality.

The invention provides a rainstorm lightning disaster risk early warning method and system based on an analytic hierarchy process, and the method comprises the steps: obtaining historical thunderstorm frequency data and thunderstorm movement path data of a target region, and analyzing and determining the sensitivity levels of different regions in thunderstorm activities; the lightning stroke risk assessment model is decomposed into a target layer, a criterion layer and a scheme layer by using an analytic hierarchy process; according to historical data including lightning stroke historical data, thunderstorm historical data and disaster damage historical data, performing pairwise comparison on each factor of the criterion layer, and constructing a judgment matrix; acquiring spatial position information and characteristics of different types of disaster-bearing bodies, performing overlay analysis according to spatial positions of the disaster-bearing bodies and the lightning drop point probability distribution map, calculating lightning stroke probability values of areas where the disaster-bearing bodies are located, and generating a disaster-bearing body risk level distribution map.