1503 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 provides a mutual inductor fault diagnosis method based on multi-sensor data fusion and transfer learning, and the method comprises the following steps: S1, installing a plurality of high-precision sensors on the secondary side of a voltage transformer to be subjected to fault diagnosis based on the voltage transformer to be subjected to fault diagnosis; s2, on the basis of the step S1, performing data acquisition and processing on data acquired by various high-precision sensors through a DHDAS dynamic signal acquisition instrument; and S3, based on the step S2, carrying out fault diagnosis on the voltage transformer through a PC (Personal Computer) carrying acquisition analysis software on the DHDAS dynamic signal acquisition instrument. According to the method, multi-mode signals such as voltage, current and temperature are synchronously collected, time-frequency domain features are extracted through continuous wavelet transform, the dynamic characteristics of interlayer short circuit faults can be more comprehensively represented, meanwhile, by combining transfer learning and a deep neural network, the intelligent diagnosis model can remarkably improve the classification performance under the condition that sample data is small, and the classification efficiency is improved. And the limitation of a single-mode signal diagnosis method is effectively overcome.

The invention relates to an error prediction method and system for an electronic voltage transformer, and belongs to the technical field of electric appliance measurement, and the method comprises the following steps: collecting historical operation data of the electronic voltage transformer, including temperature, humidity, load voltage, secondary voltage and a historical ratio error value; a time sequence convolutional neural network TCN is selected as a basis, an error prediction model is constructed in combination with a linear attention mechanism, and offline learning is performed by using historical data. Operating data is collected in real time, the relative entropy of the operating data and historical data is calculated, and a distribution threshold value is set; and when the relative entropy exceeds a threshold value, updating model parameters online by using real-time data. According to the method, the data distribution change is detected through the relative entropy, and the prediction precision of the model in a dynamic environment is ensured. The relative entropy serves as an index for measuring probability distribution differences, data distribution mutation can be effectively recognized, online learning can be triggered, the model can be dynamically adjusted, and errors of the electronic voltage transformer can be predicted more accurately.

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.

An oil-immersed insulating combined transformer for an ultrahigh-voltage electric power system, wherein a current transformer secondary winding (7) in an oil conservator (2) of the combined transformer is arranged in an aluminum current transformer housing (8); ring insulation (9) is provided outside the aluminum current transformer housing (8); an insulating tube (11) and lead insulation (12) are provided inside a porcelain bushing (3), and the lead insulation (12) and the ring insulation (9) are integrally arranged; the insulating tube (11) supports the aluminum current transformer housing (8) and is arranged in the lead insulation (12); a voltage transformer core assembly (19) comprises a voltage transformer core column (13), which has a lead through hole (20) in the middle and is arranged in the insulating tube (11); a secondary lead of the current transformer secondary winding (7) passes through the lead through hole (20); and a voltage transformer secondary winding (15) is wound on the voltage transformer core column (13) and is arranged between the voltage transformer core column (13) and the insulating tube (11). The transformer can be safely applied to an ultrahigh-voltage electric power system.

The invention discloses a capacitive voltage transformer for a gas insulated substation, which comprises a capacitive voltage divider and an electromagnetic unit, the capacitive voltage divider comprises a high-voltage capacitor C1 and a medium-voltage capacitor, the medium-voltage capacitor comprises a medium-voltage capacitor C21 and an externally connected medium-voltage capacitor C22, and the capacitance of the medium-voltage capacitor C22 is greater than that of the medium-voltage capacitor C21; the electromagnetic unit is connected with the capacitive voltage divider, an intermediate transformer and a compensation reactor are arranged in the electromagnetic unit, a full-shielding high-voltage shielding cover is arranged outside a high-voltage coil of the intermediate transformer, a damper and an overvoltage protector are arranged outside the electromagnetic unit, and the damper and the overvoltage protector are placed in an external junction box. The problem that in the prior art, an extra-high voltage transformer is low in lightning impulse overvoltage tolerance capacity is solved, the impulse overvoltage tolerance capacity is improved, and the breakdown risk is reduced.

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 provides a voltage transformer test method and system, a storage medium and electronic equipment, and relates to the technical field of voltage transformers. According to the technical scheme provided by the invention, the corresponding test items are selected according to the to-be-put scene of the voltage transformer, and meanwhile, the plurality of test items are divided into the first test item combination which can share the same simulation working condition for testing and the second test item which needs to independently simulate the working condition, so that the low-efficiency condition of repeatedly constructing a complex simulation environment is avoided; the test efficiency is greatly improved; and the target simulation working condition is obtained through parameter updating of each first test item, so that the test result is more accurate. And finally, the first test item and the second test item are tested under different simulation working conditions, so that the test efficiency of the voltage transformer can be improved on the basis of ensuring the test precision.

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.

The invention relates to the field of data processing, in particular to a voltage transformer operation state on-line monitoring method, which comprises the following steps: acquiring historical operation data of a voltage sequence, a current sequence and a temperature sequence of a voltage transformer, preprocessing the historical operation data, and acquiring a period of the historical operation data, screening a common period set in the period sequence of the data of each dimension at the same moment, and identifying the most fit period; constructing an anomaly detection model for the most fit period; and obtaining a period similarity between the real-time operation data and the historical data segment of each most fit period, obtaining an abnormal result of the abnormal detection model corresponding to each most fit period, taking each period similarity as a weight, obtaining a comprehensive abnormal probability, and judging the operation state of the voltage transformer based on the comprehensive abnormal probability. According to the method, natural fluctuation and actual abnormal conditions in normal operation can be distinguished through periodic analysis, so that false alarms and missing alarms are reduced, and the detection accuracy is 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 relates to the technical field of power distribution network fault detection, in particular to an electromagnetic voltage transformer ferromagnetic resonance fault identification method, system and device and a storage medium. The identification method comprises the following steps: collecting, preprocessing and analyzing a zero-sequence voltage signal of a primary side of a power distribution network system; feature indexes of the low-frequency IMF component in the time domain and the frequency domain are solved and subjected to dimensionality reduction reconstruction, and the most appropriate dimensionality is determined to form a fault recognition feature vector matrix; and establishing a sample set, training a sample subset, building, training and configuring an RF model to construct a fault recognition model, and performing fault recognition on the sample set to judge the fault type of the sample. The improved CEEMD time-frequency signal decomposition method based on the T test and the variance contribution rate is provided for overcoming the defects that the number of IMF components obtained through CEEMD decomposition and the frequency band of the IMF components are not fixed, and a few pseudo-modal IMF components appear in a decomposition result, and KPCA is introduced for feature dimension reduction to solve the problem that redundant information exists due to excessive feature quantities.

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 method for detecting broadband transmission characteristics of a capacitor voltage transformer (CVT), which comprises the following steps of: inputting a uniform white noise signal into a test system without a tested CVT, and calculating a transfer function H (f) of the test system and a corresponding compensation function A (f); a reference test voltage is constructed by superimposing multiple harmonic waves on the fundamental wave voltage, a reference spectrum Y (f) is obtained through Fourier transform, and a driving spectrum X (f) and a driving signal x (t) are obtained by combining the compensation function A (f); a driving signal x (t) is applied to a test system provided with a tested CVT, a test voltage ui (t) applied between a primary side medium voltage end of the tested CVT and the ground is collected, a response signal measurement spectrum Ui (f) of the test system is obtained through Fourier transform, and then the driving signal x (t) is corrected according to an error spectrum of the response signal measurement spectrum Ui (f) and a reference spectrum Y (f), so that the voltage signal ui (t) meets design requirements; and collecting the test voltage uo (t) output by the secondary side of the tested CVT at the moment, and calculating the transmission characteristic parameters of the tested CVT by combining the test voltage ui (t) and the test current ii (t) of the medium-voltage end of the tested CVT at the moment.

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 discloses an online monitoring method for a capacitor voltage transformer, and the method relates to setting a host and a plurality of slaves which communicate with each other in a wireless or wired manner. And each slave comprises a slave MCU and an AD acquisition module and is used for synchronously acquiring fault signal data of the CVT transformer. Collected data are transmitted to the host computer through the slave computer MCU, and the host computer is responsible for reading and storing the data and carrying out comparative analysis. By comparing the data of the plurality of slaves at the same moment with the historical data of the same slave, the host can identify a fault point and send out corresponding alarm information. The method achieves the real-time monitoring of the CVT, and improves the safety and stability of a power system.

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 discloses an oil-immersed power transformer monitoring method, and relates to the field of power systems, and the method comprises the steps: collecting data, collecting historical operation data, and carrying out the preprocessing; performing feature extraction on the preprocessed sensor data and historical operation data to form a sensor data feature vector and a historical operation data feature vector; fusing the sensor data feature vector and the historical operation data feature vector to form a comprehensive feature data set; establishing a fault threshold based on the historical operation data; establishing a transformer fault prediction model based on the comprehensive feature data set, and outputting a transformer fault occurrence probability; automatically adjusting a fault threshold according to a transformer fault prediction result; generating an environment state report based on the current environment state; formulating and executing a dynamic compensation strategy according to the environment state report; according to the invention, early warning of potential faults of the transformer is realized. Preventive measures can be taken before the fault occurs, and the influence of the fault on the power grid is reduced.

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 invention discloses a voltage balancing device of a 10KV three-element combined mutual inductor and a using method of the voltage balancing device, and relates to the technical field of mutual inductors. The voltage balancing device of the 10KV three-element combined mutual inductor comprises a first mutual inductor shell, the voltage balancing device comprises a second mutual inductor shell, a voltage mutual inductor is installed in the first mutual inductor shell, and a current mutual inductor is installed in the second mutual inductor shell. The front end of the first mutual inductor shell is fixedly connected with a mutual inductor junction box, a voltage stabilizer is installed outside the first mutual inductor shell, and by means of Y-shaped connection of a secondary winding of the voltage mutual inductor and use of a circuit breaker and the voltage stabilizer, voltage balance of the voltage mutual inductor is facilitated; the Y-shaped connection can guarantee three-phase balance while providing a stable power supply, has an effect of absorbing harmonic waves, improves the power supply efficiency, avoids equipment damage caused by overload, and guarantees good operation of low-voltage power grid protection.

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 discloses a 17.5 kV ring main unit. The 17.5 kV ring main unit comprises an outdoor box shell and a ring main unit shell which are integrally designed. The upper end of the box body is hinged with an upper door plate, the middle part is provided with a gas box, the lower end is provided with a cable chamber and a cable withstand voltage test chamber, and the top is an instrument chamber. Load switches are arranged on the two sides of the gas tank symmetrically, and a circuit breaker switch is embedded in the middle of the gas tank and connected through a CV busbar. The load switch is provided with an arc extinguishing grid sheet, an insulating umbrella skirt and a specially-designed grounding contact, so that arc extinguishing can be effectively realized, the insulating performance is improved, and the grounding effect is optimized. The design of the transmission assembly accurately controls the motion of the moving contact. The circuit breaker switch comprises a vacuum bubble and other components, and can efficiently extinguish arc. In addition, the lower end of the load switch is provided with test and incoming and outgoing line terminals, the driving unit is provided with a program lock, and the instrument chamber is provided with a power supply and a voltage transformer. The ring main unit optimizes space utilization through integrated design, has remarkable advantages in the aspects of electrical performance, operation convenience and maintenance, is suitable for various electric power scenes, and powerfully ensures stable operation of an electric power system.

The invention relates to a test method and device for examining broadband measurement performance of a capacitor voltage transformer. The method comprises the following steps: frequency response test: acquiring sine wave voltage signals and first output voltage signals output by the capacitor voltage transformer to be tested for multiple times; processing the signals at different frequency points to obtain gain, phase characteristics and steady-state response capability at each frequency point; a square wave signal transmission test: collecting a square wave voltage signal and a second output voltage signal output by the capacitor voltage transformer to be tested; carrying out signal time-frequency domain analysis to obtain rapid voltage change transient response capability and broadband measurement accuracy; an operation / lightning impulse transmission test: collecting a transient operation / lightning impulse wave voltage signal and a third output voltage signal output by the capacitor voltage transformer to be tested; signal processing is carried out, and the response capability and high-frequency measurement accuracy of the transient high-frequency voltage signal are obtained; and the broadband measurement performance is obtained. Compared with the prior art, the method has the advantages of comprehensively examining the broadband measurement performance of the capacitor voltage transformer and the like.

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.