24 results about "Capacitor voltage transformer" patented technology

The invention discloses a capacitor voltage transformer harmonic error prediction method based on NRBO-BP, and belongs to the technical field of modeling prediction. The method comprises the steps of analyzing harmonic transmission characteristics, adjusting stray capacitance numerical values to simulate different operating environments, performing simulation to obtain harmonic error data, optimizing initial weight and bias of a BP neural network by using an NRBO algorithm, constructing a harmonic error prediction model, and finally predicting 2-60 times of harmonic errors by taking typical harmonic errors as characteristic parameters. The performance of the model is evaluated by adopting a mean absolute error, a root-mean-square error and a decision coefficient, wherein the NRBO algorithm comprises the steps of population initialization, Newton-Raphson search and TAO trap avoidance; the method solves the problems of low model precision and susceptibility to environmental interference in the existing CVT harmonic error prediction, effectively improves the measurement precision of the CVT in the harmonic frequency band, and provides reliable technical support for harmonic analysis of a power system.

The invention discloses a capacitor voltage transformer transient voltage measurement method, device and equipment and a medium, and relates to the technical field of power grid transient voltage measurement, and the method comprises the steps: carrying out the piecewise linear fitting of a flux linkage-current curve of a CVT intermediate transformer, and obtaining a relation function of the piecewise current and the flux linkage; constructing a voltage numerical equation from the secondary side to the primary side of the CVT, wherein the voltage numerical equation considers ground distributed capacitance parameters of the CVT; and substituting the secondary side voltage value of the CVT collected in real time into the voltage numerical equation, and calculating the primary side voltage of the CVT in combination with the relation function of the segmented current and the flux linkage. According to the method, the primary side voltage of the CVT can be obtained according to the actually measured voltage value of the secondary side by constructing the voltage numerical value relation from the secondary side to the primary side of the CVT and combining the flux linkage-current relation curve, the transient response performance of the CVT is improved, and a technical basis is provided for power grid transient voltage measurement and related research.

The invention discloses a broadband harmonic voltage measuring system and method based on an improved CVT, and the system comprises a first current sensor which is used for measuring the first current of a high-voltage capacitor of the CVT; the broadband harmonic wave acquisition device is used for sampling the first current to obtain first current sampling data; and the broadband harmonic analysis device is used for determining an amplitude frequency spectrum of the first current based on the first current sampling data and determining each frequency component of the system voltage based on the amplitude frequency spectrum of the first current. On the basis of a large number of CVTs used in a power system, the broadband harmonic voltage measurement function within the range of hundreds of kHz is achieved by improving the CVT, the original power frequency measurement function of the CVT is not changed, the operation reliability of the CVT is not reduced, and effective broadband, high-precision and low-cost harmonic voltage measurement can be achieved.

The invention provides a hooking system for a capacitor voltage transformer test. The hooking system comprises a base, a lifting device, a first rotary telescopic device, a first hook, a first patch cord and a control module, the lifting device is used for driving the first rotary telescopic device to ascend and descend in the vertical direction. The first rotary telescopic device is used for driving the first hook to rotate in the vertical direction and driving the first hook to stretch out and draw back in the horizontal direction. The first end of the first patch cord is arranged on the base, and the second end of the first patch cord is connected with the first hook; and the control module is used for controlling the lifting device and the first rotary telescopic device, so that the first hook is hooked at a target position of the capacitor voltage transformer. According to the hooking system for the capacitor voltage transformer test, mechanical adjustment of the spatial position of the first hook is realized, so that the first hook is efficiently and safely hooked at the target position of the capacitor voltage transformer.

The invention relates to the technical field of online monitoring of capacitor voltage transformers, in particular to a calibrator and method for an online monitoring device of a capacitor voltage transformer, the calibrator comprises a difference adding module, an algorithm module and a judgment module, the difference adding module generates a plurality of groups of differential voltage signals, inputs the differential voltage signals into the online monitoring device and forms parameter vectors to be estimated; the algorithm module obtains a related voltage amplitude calculation theoretical ratio error, and constructs a hybrid optimization algorithm in combination with a Markov chain Monte Carlo method and a simulated annealing algorithm to calculate a posterior probability density so as to obtain the uncertainty of an error measurement result; and the judgment module combines the historical average uncertainty, the real-time temperature and the use year of the online monitoring device to calculate a verification parameter, compares the verification parameter with a preset threshold value and outputs an abnormal judgment result. According to the invention, non-power-cut verification can be realized, the verification efficiency and accuracy are improved, and the reliability of power supply of a power grid is guaranteed.

The invention relates to a capacitive voltage transformer for a converter station of an extra-high voltage direct current transmission project, which is characterized in that a secondary coil A, a secondary coil B and a secondary coil C in a secondary winding of an intermediate transformer have the same wire diameter, and when the secondary winding is wound, a secondary residual coil is wound on an insulating paper tube; the da end of the secondary residual coil is led out from the head end of the insulating paper tube, the dn end of the secondary residual coil is led out from the tail end of the insulating paper tube, then a secondary coil D is wound on the secondary residual coil, the 4a and 4n ends of the secondary coil D are led out from the tail end of the insulating paper tube, and then a secondary coil A, a secondary coil B and a secondary coil C are simultaneously wound on the secondary coil D in parallel, and 1a and 1n ends of the secondary coil A, 2a and 2n ends of the secondary coil B and 3a and 3n ends of the secondary coil C are led out from the head end of the insulating paper tube. The method has better accuracy performance and higher overvoltage bearing capacity, and can meet the use requirements of the converter station of the extra-high voltage direct current transmission project.

The utility model discloses a wired synchronization module suitable for a capacitor voltage transformer. The wired synchronization module comprises a synchronous current detection circuit and a sequential circuit. The synchronous current detection circuit utilizes a current detection chip U1, receives 3.3 V working voltage synchronous signals through a signal input pin VI of the current detection chip U1, and outputs current detection signals to a VREF end through a signal output pin VO. The capacitor C1 and the capacitor C2 are respectively connected in series between the grounding pin GND and the signal input pin VI and between the grounding pin GND and the signal output pin VO to play a filtering role. The sequential circuit comprises a connector J1, an array resistor, a reverse protection diode D1 and two operational amplifier comparators U2 and U3. The operational amplifier comparator U2 and the operational amplifier comparator U3 further process the current detection signal and finally output a synchronizing signal through a 220SYNC line. According to the design, the precision of clock synchronization is improved, the anti-interference capability of the module is enhanced, and the stability and the reliability of a capacitor voltage transformer system are ensured.

The present application relates to a kind of wind farm transmission line three-phase adaptive reclosing method and system based on frequency difference, belong to the field of power system relay protection.The method first in the maximum sliding time window, using capacitor voltage transformer (CVT) acquisition line M end voltage wave data and pre-processing;Using Fourier transform (FFT) to voltage signal is spectrum analyzed, obtain the amplitude-frequency curve with frequency as abscissa and amplitude as ordinate;Calibrate amplitude-frequency curve local peak, calculate the difference between the frequency corresponding to each peak;Adjacent sliding time window is judged whether the difference of frequency is equal, if equal, fault still exists, not reclosing circuit breaker, if the difference of frequency is not equal, then judge fault disappears, calculate the moment of fault disappearance, combined with the ionization after fault disappearance and determine reclosing time, output closing signal.The present application has lower sampling rate requirement, smaller error, easy to realize.

The present application relates to the technical field of high-voltage measuring device of electric multiple unit power system, and particularly relates to a capacitive voltage transformer for electric multiple unit. The voltage transformer is formed into an integrated full-enclosed main insulator by epoxy resin vacuum casting, and the primary high-voltage terminal is a stepped round table type standard C head structure. The inside is composed of a high-voltage capacitor and a low-voltage capacitor to form a capacitive divider, cooperate with a reactor to realize impedance compensation, cooperate with a damper to suppress resonance and overvoltage, and set a protection gap to realize overvoltage protection, and all wiring terminals are arranged in a sealed secondary wiring table. The present application has the advantages of capacitive voltage division and electromagnetic measurement, has the characteristics of small size, flexible installation, anti-resonance, anti-interference, high precision, strong protection, maintenance-free, etc., can adapt to the compact space and harsh operating environment of electric multiple unit, and is suitable for high-voltage measurement and relay protection system of electric multiple unit.

A method for measuring a dissipation factor of a voltage divider of a capacitor voltage transformer (CVT). The CVT includes a capacitor voltage divider (CVD), an intermediate voltage transformer (IVT), and a compensating reactor (CR). The CR is connected between the CVD and the IVT. The method includes measuring a grounded specimen test (GST) mode current that passes through a first capacitor of the CVD by coupling the current sensor in series with the first capacitor, measuring an ungrounded specimen test (UST) mode current that passes through a second capacitor of the CVD by coupling the current sensor in series with the second capacitor, and obtaining a dissipation factor of the CVD based on the GST mode current and the UST mode current.

The utility model relates to the technical field of transformer detection, and discloses an integrated mutual inductor detector which comprises a box body, one surface of the box body is used as a panel, and the panel is provided with a display screen, a CT line bank, a PT line bank, a power switch button and a selection switch button set. An electromagnetic voltage transformer detection board, a capacitor voltage transformer detection board and a current transformer detection board are installed in the box body. Data acquisition ports of the electromagnetic voltage transformer detection board, the capacitor voltage transformer detection board and the current transformer detection board are respectively connected with a CT connector bar or a PT connector bar through contacts of corresponding relays, and power supply ports are respectively connected with power supply wiring holes used for accessing a power supply through the contacts of the corresponding relays and a power supply switch. And the signal input and output ports are respectively connected with the display screen through contacts of the corresponding relays. According to the utility model, the detection convenience is improved.

The invention discloses an anti-explosion capacitive voltage transformer which comprises a metal expander, a capacitive voltage divider and an electromagnetic unit, the metal expander is of an external micro-positive pressure type structure and is installed at the top end of the capacitive voltage divider, an oil level gauge is arranged on the side face of the metal expander, and the electromagnetic unit is installed at the top end of the capacitive voltage divider. A protective cover is installed outside the metal expander, and an oil level observation window is formed in the position, corresponding to the oil level indicator, of the protective cover. The capacitive voltage divider comprises a capacitor core body and a porcelain bushing, the capacitor core body comprises a high-voltage capacitor and a low-voltage capacitor, the capacitor core body is sealed in the porcelain bushing, the capacitive voltage divider is filled with natural ester insulating oil, the electromagnetic unit is fixedly connected with the low-voltage capacitor end of the capacitive voltage divider, and the electromagnetic unit is filled with natural ester insulating oil. And the anti-explosion and monitoring performance of the equipment is fundamentally improved from two aspects of an insulating medium and a structural design.

The utility model discloses an AD acquisition module suitable for a capacitor voltage transformer, and the AD acquisition module carries out serial communication with a slave MCU through an SPI line, and can be connected with and collect fault signals of a plurality of CVT transformers. Key components such as an AD acquisition chip U7, a linear voltage regulator U6 and a crystal oscillator Y1 are integrated in the module. Wherein the AD acquisition chip U7 is provided with a plurality of groups of acquisition pins, and each group of pins comprises a positive electrode input and a negative electrode input which are respectively connected with a live wire and a zero wire of the CVT so as to realize accurate fault signal acquisition. The AD acquisition module has the characteristics of compact structure, stable performance, high acquisition precision and the like, and is suitable for an on-line monitoring system of the capacitor voltage transformer.

The invention relates to the technical field of capacitive voltage transformer detection, in particular to a 110kV capacitive voltage transformer disassembly-free lead dielectric loss and capacitance detection device and method, and the method comprises the steps: enabling an acquisition input assembly to be remotely clamped at a grounding lead, and collecting a current signal of the grounding lead in a non-access manner through the electromagnetic induction principle; the data processing unit obtains a current signal of the grounding lead and introduces a digital integration technology to carry out conversion processing on the current signal; and the variable-frequency anti-interference dielectric loss instrument obtains the capacitance and dielectric loss values of the main capacitor and the voltage-dividing capacitor through vector operation. According to the invention, the secondary side current of the 110kV capacitor voltage transformer to be detected is obtained through non-contact current detection without dismounting a lead or removing grounding protection in work, and detection of the capacitance and dielectric loss values of the main capacitor and the voltage-dividing capacitor is completed, so that high-altitude operation of detection personnel is not needed, the detection efficiency is ensured, time and labor are saved, and the cost is reduced.

The present disclosure discloses a method and system for measuring a frequency characteristic of a capacitor voltage transformer, and a terminal. The technical solutions are: collecting, with a transient voltage of a power system as an excitation voltage on a primary side of the CVT, a response of a secondary side of the CVT to the transient voltage, to obtain a transient voltage response; performing spectrum analysis on the transient voltage response, identifying a valley point and a peak point, and extracting a valley frequency corresponding to the valley point and a peak frequency corresponding to the peak point; and calculating a stray parameter of the CVT according to the valley frequency and / or the peak frequency, to obtain a frequency characteristic measurement result. According to the present disclosure, online measurement of the frequency response characteristic of the CVT can be implemented.

The invention relates to a multi-section capacitor type voltage transformer which comprises a capacitor and an oil tank. The capacitor comprises a first grading ring, a capacitance voltage dividing group, a second grading ring, a box body and a damping base which are sequentially connected from top to bottom. The capacitive voltage dividing group comprises a plurality of coaxially arranged sleeves, a third voltage equalizing ring is arranged between every two adjacent sleeves, and the box body is connected with an oil tank through a power cable; the damping base comprises a transition plate, a support and a damper set. According to the damping base of the multi-section capacitor voltage transformer, the support serves as a main bearing frame, the cushion block is installed in the middle of the top face of the top plate, continuous and large-area center supporting is provided, a core weight area of the transformer is supported, and a stable fulcrum is formed; the shock absorbers surrounding the cushion block can effectively absorb and isolate vibration and impact from all directions, and the shock absorbers cooperate with friction damping provided by the cushion block, so that the shock resistance of the multi-section capacitor voltage transformer is effectively improved.

The invention discloses an intelligent compensation type capacitive voltage transformer which comprises a low-frequency compensation branch circuit which adopts a series resonance isolation and parallel capacitive compensation structure, a first series resonance inductor L1 and a first series resonance capacitor C1 are connected in series and then are connected with a parallel compensation capacitor Ccomp in parallel, and the series resonance of the L1 to the C1 at a power frequency is realized to realize the transparency of a power frequency signal; capacitive compensation is provided in a low-frequency band through the Ccomp; the power frequency unvarnished transmission branch adopts a parallel resonance selection + series fine adjustment structure, a second parallel resonance inductor L2 and a second parallel resonance capacitor C2 are connected in parallel and then are connected in series with a fine adjustment resistor Rfine, parallel resonance is carried out near the power frequency through the L2-C2 for fine adjustment, and resistive compensation is provided at the power frequency band through the Rfine; and the high-frequency compensation branch circuit adopts a parallel resonance isolation + series inductive compensation structure, a series compensation inductor Lcomp is connected in series with a branch circuit formed by connecting a third parallel resonance inductor L3 and a third parallel resonance capacitor C3 in parallel, parallel resonance is realized at a low-frequency position through the L3-C3 to realize isolation, and inductive compensation is provided at a high-frequency band through the Lcomp.

The application relates to a capacitor package lead bending mechanism and method of a capacitive voltage transformer, wherein a work station upper end middle part is provided with a work station support, the left and right sides of the work station support are provided with moving devices, the rear side of the work station support is provided with a pressing mechanism, the pressing mechanism is provided with a pressing seat, the front end of the pressing seat is provided with a flexible pressing plate assembly, a first bending mechanism and a second bending mechanism are arranged on the moving devices on the left and right sides of the work station support, the first bending mechanism is provided with a first lifting bending plate, the lower side of the first bending plate is provided with a first limiting air cylinder, the second bending mechanism is provided with a second lifting bending plate, the upper side of the second bending plate is provided with a second limiting air cylinder, the work station support is provided with a supporting table surface for supporting the capacitor package, and the supporting table surface is provided with a slot for the second bending plate. The capacitor package upper end one side and lower end the other side lead bending and flattening operation can be completed at one time, and the lead bending and flattening quality and production efficiency are improved.

The invention discloses an uninterruptible power failure abnormity diagnosis method for a capacitor voltage transformer and a related device. The method comprises the following steps: acquiring a voltage data set of the transformer under an uninterruptible power failure condition; calculating statistical values according to the mutual inductor voltage and the hitching bus voltage based on a T check-statistical method, and selecting a first maximum absolute statistical value and a second maximum absolute statistical value; if the transformer is judged to be abnormal according to the first maximum absolute statistical value and the first evaluation threshold value, triggering an alarm mechanism, and if not, calculating a maximum relative statistical value according to the first maximum absolute statistical value and the second maximum absolute statistical value; whether the mutual inductor is abnormal or not is diagnosed according to the maximum relative statistical value and the second evaluation threshold value, and an abnormality diagnosis result is obtained. The technical problems that in an existing scheme, timely universal detection analysis cannot be achieved for different equipment periods, misleading influences caused by difference between standard test data and actual equipment states cannot be overcome, and consequently the detection result is lack of timeliness, universality and accuracy can be solved.

The invention discloses a method, a device and equipment for testing capacitance and dielectric loss of an integrated CVT (capacitor voltage transformer), and relates to the technical field of circuit detection. A first current and a second current generated by a voltage dividing capacitor and an intermediate transformer when a dielectric loss tester applies a test voltage are respectively collected through an external current coupler, and an equivalent current equivalent to a main capacitor is synthesized based on the first current and the second current; and then the equivalent current and the first current are sent to a dielectric loss tester to synchronously calculate the capacitance and dielectric loss parameters of the voltage dividing capacitor and the main capacitor, so that the complete acquisition of the key insulation parameters of the integrated CVT can be completed without climbing to remove a high-voltage lead by an operator.

The utility model relates to a kind of high voltage capacitor voltage transformer transient response test system, including voltage regulating unit, output end and high voltage vacuum switch, the capacitor of being tested capacitor voltage transformer, reference voltage transformer connection;High voltage vacuum switch control loop, including closing button, and multiple branches connected with it;The multiple branches are located in high voltage vacuum switch, and the one end of the closing button and multiple branches connection is as control end and phase selector connection;Electronic measuring equipment, with reference voltage transformer secondary side terminal, the secondary side current transformer of being tested capacitor voltage transformer, being tested secondary side terminal connection.The utility model can complete the existing international general two kinds of frequency 50Hz and 60Hz voltage transformer transient response test, facilitate voltage transformer secondary terminal measurement wiring, make transient response test process simplify, improve overall test safety factor, guarantee personnel safety, improve transient response test efficiency.

The utility model belongs to the technical field of electrical equipment, concretely relates to a PT cabinet arrangement structure for inhibiting 10kV motor feeder cabinet overvoltage, the utility model discloses a suitable capacity capacitor is arranged in the PT cabinet of motor feeder cabinet side and is connected into the medium voltage system bus, can when motor feeder cabinet encounters thunder overvoltage situation, through capacitor reduces the steepness of thunder invasion wave, to protect motor vertical insulation, simultaneously through the reasonable arrangement of each element in PT cabinet, its overall structure is compact, and the operation is flexible, does not occupy the other cabinet body space of medium voltage system bus, and through the setting of capacitor, voltage transformer, lightning arrester, electrified indicating lamp etc. electrical components below handcart type isolator, can when PT cabinet electrical equipment overhauls, timely isolation equipment and power supply, form the obvious visible disconnecting point, to avoid the electrified condition of overhauls, effectively guarantee the safety of staff and equipment.

The invention discloses a CVT aging life prediction method and device based on dielectric loss, terminal equipment and a storage medium, and belongs to the field of dielectric loss measurement, and the method comprises the steps: obtaining the dielectric loss data of a to-be-measured capacitor voltage transformer; according to the dielectric loss data, relaxation time distribution of the capacitor voltage transformer to be tested is determined; according to the relaxation time and a multi-physical field model, generating an initial comprehensive aging factor of the to-be-tested capacitor voltage transformer; updating the initial comprehensive aging factor to obtain a final comprehensive aging factor of the to-be-tested capacitor voltage transformer; and performing nonlinear life probability modeling on the basis of the final comprehensive aging factor to obtain residual life probability density, and performing life prediction on the basis of the residual life probability density to obtain the aging life of the to-be-tested capacitor voltage transformer. The problem of low aging life prediction accuracy of the capacitor voltage transformer in the prior art can be solved.

The invention discloses a capacitor voltage transformer of an energy storage power station, and belongs to the technical field of voltage transformers, the capacitor voltage transformer comprises a transformer main body, cushion blocks are fixedly mounted on the left and right sides of the bottom of the transformer main body, and first clamping blocks are arranged on the front and rear sides of the left and right sides of the transformer main body; and first positioning bolts are arranged at the top and the bottom of one side of the first clamping block correspondingly, a damping pad is fixedly mounted at the bottom of the cushion block, and damping rods are fixedly mounted on the front side and the rear side of the bottom of the damping pad correspondingly. The transformer body can be quickly disassembled and assembled, quick connection of the transformer body and the transformer body can be achieved, installation steps are greatly reduced, meanwhile, follow-up maintenance is facilitated, a certain buffering and damping function is achieved, the influence of external vibration on internal elements of the transformer can be effectively reduced, and the service life of the transformer is prolonged. The use length of the mounting plate can be flexibly matched according to a mounting frame of the energy storage power station, and the mounting adaptability is obviously improved.