1083 results about "Potential transformer" patented technology

The invention relates to the technical field of control systems, in particular to a control system and a control method of an intelligent permanent magnet vacuum circuit breaker, and the system comprises a multi-source signal synchronous acquisition module, an operation mechanism box body of the permanent magnet vacuum circuit breaker and acceleration sensors arranged at preset positions around a permanent magnet operation mechanism, a voltage transformer and a current transformer are connected to a line interface, and a unified sampling frequency and a trigger condition are set. According to the method, vibration, voltage and current signals are synchronously collected at key parts of the permanent magnet vacuum circuit breaker, timestamps are applied, a data basis of multi-source information strong association is constructed, and the direct time sequence relation between the electrical transient state and the mechanical response can be revealed. Segmented windowing and frequency spectrum transformation are carried out on collected vibration signals, a time frequency energy distribution diagram is generated, and instantaneous frequency components and energy evolution details generated by non-stationary events such as impact and friction in the opening and closing process are captured.

The invention relates to the technical field of voltage control, in particular to a synchronous main shift gear automatic compensation voltage control system, which comprises an area load information acquisition module, a voltage instantaneous value and a current instantaneous value are periodically read through a voltage transformer and a current transformer which are deployed on a key feeder line or a user side in a specified area, and the voltage instantaneous value and the current instantaneous value are acquired; and calculating to obtain an active power value and a reactive power value, adding a synchronous timestamp and a node position code to each collected value, transmitting and collecting the coded voltage value, active power value, reactive power value and timestamp information, organizing and storing according to a regional and time sequence, and establishing a regional load real-time measurement data set. According to the method, real-time capturing and structured processing of the system call number, the parameter and the return value are carried out on the L4T kernel event triggered by the target process PID, a serialized system call track is obtained, and an execution process recording path mainly driven by process behaviors is formed.

The invention provides an intelligent monitoring and early warning method based on multi-source information fusion, and belongs to the technical field of intelligent diagnosis and early warning, and the method comprises the steps: synchronously collecting the multi-modal data of a voltage transformer, the multi-modal data comprising voltage / current waveform, partial discharge signal, temperature and vibration data; preprocessing the multi-modal data, wherein a preprocessing method comprises waveform segmentation, spectrogram generation and scalar normalization; constructing a dynamic weight distribution mechanism: calculating a weight matrix based on the relevance between the time sequence features and the spatial features, and dynamically adjusting scalar weights by combining the physical coupling relationship between the temperature and the vibration to generate feature fusion weights; iteratively updating the weight matrix according to the real-time prediction error; fusing the time sequence features, the spatial features and the scalar features through the dynamic weight distribution mechanism to generate a comprehensive feature vector; and synchronously outputting a fault type classification result and an equipment health score based on the comprehensive feature vector, and calculating a real-time prediction error.

The invention relates to the technical field of voltage transformers, in particular to a voltage transformer real-time monitoring system based on broadband and edge calculation, which comprises the steps of collecting multiple paths of voltage transformer data, extracting peak values and zero cross points, comparing jump rising edge time differences, unifying time sequences, extracting extreme values and slope identification disturbance sections, and monitoring the voltage transformers in real time. Measuring amplitude continuous change to judge the offset trend, analyzing trend direction classification waveform fragments, and combining the three indexes to generate an operation state label. According to the method, a unified time sequence is constructed by comparing cross-channel jump rising edge time differences, multi-channel jump process alignment is achieved, the synchronous anomaly recognition capability is improved, the number of extreme values and the slope direction are extracted to recognize a disturbance dense section, continuous anomaly is judged by combining statistics of overrun, and the fluctuation trend is judged by tracking the deviation trend between extreme values. And based on the three-index combination classification operation state, the anomaly identification precision is improved.

According to the multi-channel feature image-based improved MobileNetV2 voltage transformer fault diagnosis method, a partial overlapping sliding window technology is used to carry out data enhancement on a secondary side voltage signal so as to construct images capable of representing different features. Through fusion of multi-channel feature images representing structure information, transient change and frequency domain characteristics, combined extraction of voltage signal multi-dimensional features is realized. On the basis, an improved MobileNetV2 diagnosis model is provided, and the nonlinear modeling capability of the network to a complex feature mode is enhanced by introducing a Mish activation function; and a normalization-based attention module (NAM) is introduced to realize dynamic focusing of fault features. Meanwhile, a receptive field of a convolutional layer is expanded by using multi-scale expansion convolution, so that correlation modeling between features is enhanced. According to the framework, the diagnosis precision of the voltage transformer is remarkably improved while the light weight of the model is kept.

The invention discloses a fault diagnosis method and system for a metering error of a voltage transformer, and relates to the technical field of power equipment fault diagnosis, and the method comprises the steps: obtaining the historical electric quantity data of a secondary side under the normal operation of the voltage transformer, and carrying out the noise reduction and normalization preprocessing; establishing an initial principal component analysis model according to the preprocessed historical electric quantity data, and calculating to obtain a statistic control threshold value; updating a mean vector and a covariance matrix of the model by adopting a dynamic strategy based on real-time acquired new electric quantity data of the secondary side of the voltage transformer; and calculating a new statistic according to the updated mean vector and the covariance matrix, comparing the new statistic with a statistic control threshold value, and if the new statistic is greater than the statistic control threshold value, determining a metering error fault. According to the invention, the model parameters can be updated according to the real-time change data output by the voltage transformer, the adaptability to different metering error ranges of the voltage transformer is improved, and the detection precision is improved.

The utility model belongs to the technical field of medium-voltage power distribution systems, and discloses an isolating switch device and a switch cabinet, the isolating switch device comprises an insulating rod, a conductive block, a conductive sheet and an operating mechanism, the conductive block is sleeved on the insulating rod, the conductive sheet is fixedly connected with the conductive block, and the operating mechanism drives the conductive sheet and the conductive block to rotate through the insulating rod. Therefore, the conducting strip is selectively connected or disconnected with the circuit breaker connector bar, and the conducting block is electrically connected with the voltage transformer in the rotating process. An isolating switch device is additionally arranged between a circuit breaker and a voltage transformer in a switch cabinet, an operating mechanism is utilized to drive a conducting strip and a conducting block to rotate through an insulating rod, the conducting block and the voltage transformer keep electrical connection in the rotating process, the position of the conducting strip is changed in the rotating process, and then the conducting strip is selectively connected with or disconnected from a circuit breaker connector bar. The structure is simplified, the number of elements is reduced, flexible operation can be achieved, and the stability and reliability of the disconnecting switch device can be guaranteed.

The invention discloses a broadband oscillation suppression device and method for a new energy field, and aims to overcome the defects of inaccurate monitoring and inflexible suppression measures in the prior art. The device comprises a three-phase impedor, a transformer and an equivalent power grid, the three-phase impedor is connected in series between the transformer and the equivalent power grid, the transformer is connected with a new energy field, and a voltage transformer and a current transformer are further connected between the equivalent power grid and the new energy field and used for monitoring voltage and current signals in real time and transmitting the voltage and current signals to a broadband oscillation monitor. The broadband oscillation monitor is connected with the three-phase impedor through the impedance switching loop, and the three-phase impedor is composed of an impedance unit composed of a plurality of sub-impedors and circuit breakers. Through precise monitoring and intelligent analysis, in combination with flexible impedance adjustment and a quick response control strategy, the defects of inaccurate monitoring and inflexible suppression measures in the prior art are effectively solved, and the suppression effect of broadband oscillation of a new energy field is remarkably improved.

A method, apparatus and system for state evaluation of metrological characteristics of a capacitor voltage transformer, relating to the technical field of voltage measurement. The method comprises the following steps: acquiring operation data of a capacitor voltage transformer, establishing a metrological performance evaluation model, and obtaining a statistical control threshold (S1); collecting in real time the operation data of the capacitor voltage transformer, and calculating a statistic of the operation data by means of the metrological performance evaluation model (S2); comparing the statistic of the operation data with the statistical control threshold to determine whether a fault occurs in the capacitor voltage transformer (S3); and detecting a change trend of a primary signal and a secondary signal of the tested capacitor voltage transformer to determine whether metrological characteristics are abnormal (S4). In the method, the concept of time is introduced, by providing a timestamp, the influence of newly obtained data on the metrological performance evaluation model is greater, and by means of real-time update, the metrological performance evaluation model can be updated, so that when in a stable state, the detection time is reduced, and the model calculation is reduced.

The invention provides a power distribution network zero sequence mutual inductor wiring polarity on-line proofreading method and system. The method comprises the following steps that 1, an active inverter is directly connected between a phase line of a power distribution network or a neutral point of a grounding transformer and the ground, or is connected between the phase line of the power distribution network or the neutral point of the grounding transformer and the ground through a boosting transformer; step 2, performing closed-loop control on the active inverter to inject zero-sequence current into the power distribution network; 3, in the injection process, judging whether the wiring polarity of the zero-sequence mutual inductor is wrong or not; 4, if only one of the zero-sequence voltage transformer and the zero-sequence current transformer has a wiring polarity error, correcting by modifying a software flag bit; and step 5, each power distribution terminal and the accessory device thereof complete online calibration of the wiring polarity of the zero sequence mutual inductor. By applying the technical scheme, the problem that the grounding fault section positioning research and judgment result is wrong due to the wiring polarity error of the zero-sequence mutual inductor of the power distribution terminal and the accessory device thereof can be avoided, and the method has good engineering application value.

The invention discloses a voltage transformer metering error evaluation method, which relates to the technical field of voltage transformer metering and comprises the following steps of: constructing a synchronous acquisition system of multiple groups of voltage transformers in a transformer substation, acquiring original voltage data, constructing a virtual reference voltage generation model and outputting a reference voltage sequence; the method comprises the steps of establishing a virtual reference voltage model, calculating error statistical characteristics, marking the operating state grade of the voltage transformer, evaluating health scores according to the error characteristics, outputting a scoring result, receiving inspection feedback comparison differences, updating the model, generating an analysis chart, and uploading the analysis chart to a client display and linkage operation and maintenance system. On-line error evaluation is realized, multi-source data are fused, error features are dynamically extracted, an operation state is marked, a health scoring and early warning mechanism is established, a feedback closed loop is introduced to optimize model precision, an evaluation result is displayed in a chart form, operation and maintenance scheduling is assisted, and the real-time performance, the accuracy and the self-adaptive capability of evaluation are improved.

The invention discloses a high-voltage voltage transformer for state grid metering, which relates to the technical field of voltage transformers and comprises a U-shaped mounting frame, a mounting square tube is fixedly mounted on one side of the U-shaped mounting frame, a sliding bottom plate is slidably connected into the U-shaped mounting frame, and a voltage transformer body is fixedly mounted at the top of the sliding bottom plate. Insulating porcelain bushings are arranged at the top of the voltage transformer body, the tops of the two insulating porcelain bushings are rotationally connected with rotating mounting frames, brake bars are fixedly mounted on the outer sides of the rotating mounting frames, and connecting contacts are fixedly mounted at the bottoms of the sides, away from the rotating mounting frames, of the brake bars. When the wiring ring is used, the position limitation of the wiring ring can be removed by directly pushing the sliding button, and the wiring ring is only required to be sleeved on the outer side of the wiring post and pressed during installation, so that the wiring is more convenient and quicker compared with the mode that a screw is directly used for fixing.

The invention discloses a CVT internal capacitance state comprehensive evaluation method and system based on temperature compensation, and belongs to the field of capacitor voltage transformer optimization compensation, and the method comprises the following steps: S1, detecting the primary voltage amplitude and phase angle of a capacitor transformer, and obtaining the performance parameters of the capacitor transformer; s2, acquiring environment temperature information; s3, determining a mathematical relationship between the environment temperature and the performance parameters of the capacitance transformer, and calculating a temperature compensation coefficient according to the mathematical relationship and the environment temperature value; s4, compensating a primary voltage amplitude and a phase angle by using a temperature compensation coefficient; and S5, analyzing the compensated voltage amplitude and phase angle data to obtain an analysis result, and evaluating whether the internal capacitance state of the capacitance transformer is normal or not according to the analysis result. By accurately detecting the primary voltage amplitude and the phase angle of the capacitance transformer and combining environment temperature information, the method can calculate an accurate temperature compensation coefficient, so that the influence of temperature change on the performance of the CVT is effectively corrected.

The invention provides a fault early warning method and system for power transmission, transformation and distribution equipment, and relates to the technical field of power transmission, transformation and distribution equipment, and the method comprises the steps: carrying out the real-time monitoring of a transformer through a sensing module, and obtaining a real-time gas concentration-generation rate, a real-time temperature rise monitoring value, and a real-time integrated monitoring parameter; the method comprises the following steps: periodically sampling a current transformer and a voltage transformer of a power distribution network in a power system to obtain a current-voltage three-phase data sequence; state analysis is carried out, and a fault early warning instruction is triggered; performing feature backtracking on the sensing module to generate a transformer feature backtracking result; performing trend feature identification on the current-voltage three-phase data sequence to generate current-voltage three-phase data trend features; and performing fault early warning analysis to obtain a fault early warning result. According to the invention, the technical problem of low fault early warning accuracy of the transformer and the power distribution equipment in the prior art can be solved, and the technical effect of improving the early warning accuracy is achieved.

The invention provides a capacitor voltage transformer error online detection method and system, and the method comprises the steps: collecting a secondary output signal of a three-phase capacitor voltage transformer, and carrying out the data preprocessing; based on the collected data, constructing a deep neural network learning model based on a stacked auto-encoder, and extracting deep features of the data through multilayer nonlinear transformation to obtain reconstructed data; taking the original data and the reconstructed data as input data, respectively carrying out co-integration analysis, and calculating a co-integration matrix and an equalization error; combining the reconstruction data with the equilibrium error, constructing a composite statistical magnitude and calculating a statistical magnitude threshold value; and collecting online measurement data of the capacitor voltage transformer, calculating monitoring statistics and carrying out abnormity diagnosis. The technical problems that disturbance components and error information in measurement data are difficult to distinguish, non-linear and non-stationary components in measurement errors of the capacitor voltage transformer are difficult to analyze, and the online detection accuracy and real-time performance of the measurement errors are low are solved.

The utility model relates to the field of resonance eliminators, and discloses a protection element and a current limiting type resonance eliminator, the protection element comprises at least two groups of protection units, the two adjacent groups of protection units are connected in series, and each protection unit comprises a protection module; the current-limiting resonance eliminator based on the current-sensitive resistor made of the current-sensitive material is connected in series between the PT neutral point and the ground. Under the normal operation condition, the current-limiting resonance eliminator is in a low-resistance state, and system parameters and PT performance are not affected; when excitation energy is generated due to a system fault, the current-limiting resonance eliminator suddenly changes into a high resistance state, quickly absorbs resonance energy, destroys resonance parameters, suppresses PT excitation current below 200mA, and ensures that a voltage transformer is unsaturated and a PT fuse is not fused; and a built-in current sensor is connected, so that the running state of the current-limiting resonance eliminator can be monitored in real time.

The invention provides an electromagnetic voltage transformer, which relates to the technical field of high-voltage measurement of an electric power system, and comprises a transformer main body, a butt joint base is arranged below the transformer main body, two butt joint plug-in frames are fixedly connected below the transformer main body, and inner positioning flanges are arranged in the two butt joint plug-in frames. And unlocking assemblies are arranged in the two butt joint sockets. Through the arrangement of the clamping assembly, when the guide assembly is pushed to enable the clamping assembly to clamp a copper bar, counter-acting force can extrude a second elastic piece, so that a piston extrudes gas in a sliding groove, when the voltage transformer vibrates, the vibration frequency can be offset through the elastic force of the second elastic piece, and the clamping assembly is prevented from loosening; when the voltage rises and the current is increased to generate heat, and the gas in the sliding groove expands after being heated, the piston is synchronously extruded to move towards the copper bar direction, and the second elastic piece is extruded for adjustment, so that the vibration reduction effect is further improved, and the detection efficiency of the electric power system is improved.

The invention discloses a voltage transformer state influence factor analysis method, system and device and a medium, and belongs to the technical field of voltage fault analysis, and the method comprises the steps: collecting state parameters of a voltage transformer, carrying out the preprocessing of the state parameters, and constructing a nonlinear coupling relation between multidimensional feature tensor capture features; analyzing voltage fluctuation characteristics of the voltage transformer, and automatically correcting the insulation state evaluation model; and inputting abnormal feature vectors obtained by monitoring into a recursive attribution decision tree model, carrying out multi-dimensional abnormal clustering and causal analysis, generating a tracing report, and carrying out multi-dimensional evaluation and verification on an analysis result. According to the invention, continuous dynamic full-coverage monitoring of the equipment insulation health condition is realized, the accuracy and robustness of anomaly detection are improved, the phenomena of missing detection and false alarm are reduced, the scientificity of anomaly tracing analysis and the interpretation of early warning decision are improved, and the reliability of the system is improved. And the intelligent level of the monitoring and early warning system is improved by continuously adapting to new abnormal types and complex operation environments.

The invention discloses a self-adaptive transformation ratio adjustment electric quantity metering method and device, the device comprises a high-voltage metering device and a control center, and the high-voltage metering device is composed of a voltage transformer, a current transformer and an electric energy meter. The core innovation point is that the current transformer is provided with a plurality of secondary windings, each winding is respectively connected with a relay with a multi-gang switch contact, the output end of the relay is connected with the electric energy meter, and the relay and the control center realize linkage control. The control center drives a multi-gang switch contact of the relay to be automatically switched to a secondary winding adaptive to the current load by monitoring the current state of the load in real time; factors such as temperature, humidity and the year of a home-entry power grid are introduced to correct a current measured value, and the accuracy of electric quantity metering is improved. Meanwhile, the control center records transformation ratio switching data in real time, reliable support is provided for time-of-use electricity price execution, demand side response and electric quantity tracing, and the intelligence and refinement level of electric power metering is remarkably improved.

The invention relates to the field of power transformers, in particular to a convenient-to-use power transformer which comprises an insulating baffle and a voltage transformer, a limiting sleeve shell is fixedly connected to the inner side wall face of the insulating baffle, and a motor and a first limiting rod are arranged on the bottom surface of the limiting sleeve shell and located on the edges of the two sides correspondingly; the output end of the motor is fixedly connected with a threaded lead screw, and the outer side surface of the threaded lead screw and the outer side surface of the first limiting rod are movably sleeved with a pushing block. The surface of a cable wire is clamped on the inner side wall surface of a pushing block, at the moment, a threaded rod is rotated, under thread drainage of a threaded sleeve, the threaded rod rotates on the surface of an extrusion arc plate and pushes the extrusion arc plate, and along with continuous penetration of the extrusion arc plate, the surface of the extrusion arc plate is attached to the outer side surface of the cable wire; and meanwhile, an anti-skid silica gel block in the pushing block is matched to increase the friction force between the cable wire and the surface of the cable wire, and the anti-skid performance is improved.

The invention provides a PT ferromagnetic resonance overvoltage suppression system and method based on graded damping. The system comprises a secondary resonance elimination module, the secondary resonance elimination module comprises a three-stage damping branch circuit which is connected in series with an open triangle of a voltage transformer, the three-stage damping branch circuit comprises a first current-sensitive resonance eliminator, a second current-sensitive resonance eliminator and a fixed resistor which are connected in parallel, and a branch circuit of the first current-sensitive resonance eliminator is connected in series with a first switch; a branch of the second flow-sensitive resonance eliminator is connected in series with a second switch, and a branch of the fixed resistor is connected in series with a third switch; the fan is used for carrying out air cooling on the first flow-sensitive resonance eliminator, the second flow-sensitive resonance eliminator and the fixed resistor; and the control module is used for controlling on or off of the first switch, the second switch and the third switch. Resonance early recognition is achieved through transient energy comprehensive criteria, three-level damping dynamic switching and fan intelligent temperature control are combined, and the three core problems of response lag, insufficient heat dissipation and weak self-adaption in ferromagnetic resonance suppression are solved.

The invention relates to a primary and secondary fusion complete column-mounted circuit breaker, which comprises a circuit breaker body, a column mounting frame, a voltage transformer, an electronic sensor, a drop-out fuse and a controller, and is characterized in that the circuit breaker body is provided with an operation base and a plurality of solid-sealed polar poles arranged on the operation base; a vacuum arc-extinguishing chamber is arranged in the upper end of a vertical section of the solid-sealed polar pole, a connecting wire extending horizontally is arranged in a transverse section of the solid-sealed polar pole, opening and closing of the vacuum arc-extinguishing chamber are driven by an operation base, and the solid-sealed polar pole further comprises a limiting assembly arranged in the solid-sealed polar pole and a conductive linkage assembly arranged in the limiting assembly. The conductive wire connecting assembly is arranged in the limiting assembly, and the accelerating assembly is arranged in the limiting assembly and located below the mounting sleeve, so that the opening speed is accelerated. The beneficial effects of the invention lie in that the linkage assembly connected with the movable conducting rod and the driving rod realizes switching-on power-on and switching-off power-off, and can also cooperate with the acceleration assembly so as to accelerate the switching-off speed.

The invention provides a new energy station high-voltage voltage transformer error evaluation method and system, and the method comprises the steps: collecting the voltage phasors of all measurement nodes in a preset time period at a transformer substation and a new energy station at the same time, obtaining the equipment parameters of a voltage transformer and the line parameters between the measurement nodes, and constructing a measurement data set; the method comprises the following steps: constructing a corresponding adjacency matrix and a node characteristic matrix by extracting line impedance and node working condition characteristics based on a power system line topological structure and data in a measurement data set, and obtaining a time sequence diagram structure data set according to the adjacency matrix and the node characteristic matrix; constructing a graph neural network, and training the graph neural network based on the time sequence graph structure data set; and inputting the voltage phasor of each measurement node, and based on the output result of the trained graph neural network, judging the state of the voltage transformer through a preset threshold value. According to the scheme, online evaluation of the error state of the voltage transformer can be realized, and the accuracy and interpretability of error evaluation are improved.

The invention relates to the field of electric power measurement, and provides a voltage transformer error evaluation method and device, electronic equipment and a storage medium, and the method comprises the steps: collecting the voltage phasor information of a measurement node in a preset time window, and obtaining the reference technical parameters of a voltage transformer corresponding to the measurement node; feature extraction based on a sliding window is carried out, sequence diagram structural features are obtained in combination with an adjacent matrix, and the adjacent matrix is constructed based on network topology and line electrical parameters of a power system; error estimation is carried out through a trained error estimation model based on the time sequence diagram structure features, an error estimation value is obtained, and the error estimation model is obtained by training a graph neural network model based on historical voltage phasor information and corresponding error labels; and performing error state evaluation based on the error estimation value. According to the method, the device, the electronic equipment and the storage medium provided by the invention, online continuous evaluation of the voltage transformer error is realized, and the limitations of long period and high cost of a traditional offline verification method are broken through.

The invention discloses a harmonic measurement error correction method and system for an electronic voltage transformer, and relates to the technical field of power electronics, and the method comprises the steps: obtaining the sparse sampling data of the electronic voltage transformer; constructing a harmonic reconstruction dictionary suitable for an asynchronous sampling condition according to the sparse sampling data and the set parameters of the sampling characteristics; extracting periodic characteristics of the sparse sampling data, performing frequency change analysis, and generating a frequency offset adaptive factor; and performing harmonic reconstruction on the sparse sampling data by adopting a multi-stage sparse reconstruction algorithm in combination with the harmonic reconstruction dictionary and the frequency offset adaptive factor to obtain a corrected harmonic component. The method can adapt to the change of dynamic frequency response of the electronic voltage transformer in different working states, considers the error formed by interweaving of the nonlinear frequency response characteristic and the frequency offset effect of the electronic voltage transformer, and improves the accuracy of harmonic measurement error correction.

The present invention pertains to methods for operation, maintenance, and monitoring of rotating electrical machines, and relates to a system and a method for monitoring the operational condition and detecting mechanical, electrical, load, and process faults in rotating electrical machines. The proposed system and method, together, provide a more effective way to detect faults early on, with greater installation convenience and scalability than prior art methods, and are more efficient in avoiding production losses, improving operational performance and preventing damage to equipment and risks to operators. The developed method continuously collects electrical current and voltage signals that power the machine, utilizing a data acquisition module and current and voltage transformers. The collected data undergoes stages of compression, encryption, application of Fast Fourier Transform (FFT), subsampling, feature extraction, anomaly detection using statistical and machine learning techniques, and fault classification using machine learning techniques. The proposed system consists of one or more data acquisition modules, one or more gateway devices, a processing center on a cloud computing platform, and an operator interface. In an industrial application, the method can be continually improved with the collection of new data and with validation information from an operator in the face of an identified fault.

The invention discloses a resonance elimination circuit, method and device, and relates to the technical field of circuits, and the circuit comprises a controller, a resonance elimination resistor and a switching circuit. Two ends of the resonance elimination resistor are respectively connected with the neutral point of the voltage transformer and the ground. The controller controls the switching circuit to be switched off when ferromagnetic resonance is detected, so that the resonance elimination resistor is connected to suppress resonance; after the fault disappears, the control switch is switched on, and the neutral point is directly grounded. The controller compares the neutral point current with a first threshold value to determine resonance generation, and determines fault disappearance when the current is smaller than a second threshold value. And when the resonance elimination resistor is a variable resistor, the controller adjusts the resistance value according to the current change rate and a pre-learned mapping relation. The switching circuit can adopt a switching tube or a relay, and the controller realizes switching by controlling the switching tube to be turned off or a relay coil to be powered off. The circuit can rapidly suppress ferromagnetic resonance, guarantee system stability and improve fault processing efficiency.

The invention discloses a voltage transformer with a rapid heat dissipation function, and relates to the technical field of voltage transformers. Comprising an insulating shell, a mutual inductor body is arranged in the insulating shell, an isolation hood is arranged on the outer side of the mutual inductor body, a cooling plate is installed above the isolation hood, a refrigeration plate is installed in the cooling plate, the cooling plate is sequentially connected with an output pipe, a middle pipe and an input pipe, the middle pipe is connected with a vortex pipe, and a collecting plate is installed below the isolation hood. A temperature measuring plate is installed in the collecting plate, damping springs are installed at the four corners of the insulating shell, air sequentially penetrates through the vortex pipes to be sucked into the middle pipe, the air is sucked through the middle pipe and then impacts with high-speed cooling liquid to form aerial fog, and the control system cools the aerial fog-shaped cooling liquid in the cooling flow channel through the refrigerating end. And the cooled aerial fog cooling liquid is sprayed on the isolation hood from the multiple groups of spraying openings, the contact area between the aerial fog cooling liquid and the isolation hood is increased, the cooling effect is improved, and the mutual inductor body is rapidly cooled.

The invention relates to the technical field of electrical engineering, and discloses a voltage transformer, a design method and device thereof and a storage medium, and the method comprises the steps: determining the size of an iron core, and the electrical parameters of a primary side winding and a secondary side winding according to the electrical performance parameters and space limitation conditions of a target voltage transformer; calculating no-load loss, no-load magnetization and no-load current of the target voltage transformer based on the ferromagnetic material attribute parameters and the iron core size; determining a leakage reactance value reduced to a secondary side and total resistance of the winding according to the winding structure parameters; establishing an initial three-dimensional finite element simulation model of the voltage transformer based on the iron core size information and the winding parameters; determining a no-load error and a load error of the voltage transformer based on the no-load loss, the no-load magnetization, the leakage reactance value, the total winding resistance and the winding structure parameters; and performing feedback optimization on the initial simulation model based on the no-load error and the load error to obtain a target three-dimensional finite element simulation model, and manufacturing a target voltage transformer based on the simulation model.

The invention belongs to the technical field of nuclear power, and particularly relates to a ground capacitance measurement method based on series capacitance and high-frequency signal injection. In order to solve the problem that a traditional signal injection method cannot accurately calculate the ground capacitance level of a power distribution network, the invention provides a ground capacitance measurement method based on a series capacitor and high-frequency signal injection. The leakage inductance of the voltage transformer is accurately measured by injecting the high-frequency signal, so that a resonance point is convenient to find during frequency sweeping, and the resonance point measured during frequency sweeping is more accurate.