CN112946515A - Online monitoring method and device for converter transformer network side sleeve - Google Patents
Online monitoring method and device for converter transformer network side sleeve Download PDFInfo
- Publication number
- CN112946515A CN112946515A CN202011569048.6A CN202011569048A CN112946515A CN 112946515 A CN112946515 A CN 112946515A CN 202011569048 A CN202011569048 A CN 202011569048A CN 112946515 A CN112946515 A CN 112946515A
- Authority
- CN
- China
- Prior art keywords
- capacitance
- relative
- calculating
- dielectric loss
- leakage current
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000012544 monitoring process Methods 0.000 title claims abstract description 29
- 238000009413 insulation Methods 0.000 claims abstract description 28
- 230000008859 change Effects 0.000 claims abstract description 20
- 238000004364 calculation method Methods 0.000 claims description 39
- 238000012806 monitoring device Methods 0.000 claims description 12
- 238000012935 Averaging Methods 0.000 claims description 10
- 238000010586 diagram Methods 0.000 description 10
- 238000004590 computer program Methods 0.000 description 7
- 238000005259 measurement Methods 0.000 description 6
- 230000002159 abnormal effect Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 238000004458 analytical method Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000004422 calculation algorithm Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000010587 phase diagram Methods 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000002547 anomalous effect Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/52—Testing for short-circuits, leakage current or ground faults
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16566—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533
- G01R19/16571—Circuits and arrangements for comparing voltage or current with one or several thresholds and for indicating the result not covered by subgroups G01R19/16504, G01R19/16528, G01R19/16533 comparing AC or DC current with one threshold, e.g. load current, over-current, surge current or fault current
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R25/00—Arrangements for measuring phase angle between a voltage and a current or between voltages or currents
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2605—Measuring capacitance
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2688—Measuring quality factor or dielectric loss, e.g. loss angle, or power factor
- G01R27/2694—Measuring dielectric loss, e.g. loss angle, loss factor or power factor
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The embodiment of the invention provides an online monitoring method and device for a side sleeve of a converter transformer substation, and particularly relates to the online monitoring method and device for synchronously collecting leakage currents of a plurality of sleeves under the same reference voltage; determining a relative dielectric loss value and a relative capacitance of each casing relative to the other casings based on the leakage current; and determining the insulation state of the corresponding sleeve according to the relative dielectric loss value and the relative capacitance. The insulating state of the sleeve is monitored in an indirect mode, compared with the prior art, the method and the device have the advantages that the leakage current of the sleeve under the condition that a plurality of same-phase running devices are measured, the leakage current and the relative dielectric loss value and the relative capacitance change rate between the devices are measured through mutual reference signals, and the insulating state of the sleeve is judged accordingly.
Description
Technical Field
The invention relates to the technical field of electric power equipment, in particular to an online monitoring method and device for a converter transformer network side sleeve.
Background
The converter transformer plays an important role in transmitting power and insulating and isolating an alternating current system and a direct current system, is one of core devices of a direct current converter station, and influences the safe and stable operation of the converter station due to the safe and stable operation of the converter transformer. The converter transformer side sleeve serves as a high-voltage lead wire to ground insulation and support, and plays a crucial role in reliable and stable operation of the converter transformer.
The damage of the bushing is mainly reflected in the short circuit of the part of the capacitor shielding layer caused by overvoltage or the local creepage of the insulation, and also reflected in the damp or the insulation deterioration of the bushing. The capacitance and dielectric loss values of the bushing are important parameters for evaluating the insulation state of the bushing. The dielectric loss value is the ratio of the active component and the reactive component of the current in the dielectric medium under the action of alternating voltage, and under certain voltage and frequency, the dielectric loss value reflects the energy loss in unit volume in the dielectric medium and is related to the volume size and the size of the dielectric medium.
The inventor of the application finds that the capacitance and dielectric loss value need to be measured by a voltage transformer (PT) on line at present, but the measurement error of the PT itself, particularly the angle difference, greatly affects the measurement accuracy of the capacitance and dielectric loss value, so that the capacitance and dielectric loss value cannot be directly obtained at present, and the reliability of the insulation state of the finally obtained bushing is poor.
Disclosure of Invention
In view of this, the present invention provides an online monitoring method and an online monitoring device for a converter transformer network side bushing, so as to solve the problem that the reliability of the current online monitoring scheme is poor when the insulation state of the bushing is monitored.
In order to solve the problems, the invention discloses an online monitoring method for a converter transformer network side sleeve, which comprises the following steps:
synchronously collecting leakage currents of a plurality of sleeves under the same reference voltage;
determining a relative dielectric loss value and a relative capacitance of each of the sleeves relative to the other sleeves based on the leakage current;
and determining the corresponding insulation state of the sleeve according to the relative dielectric loss value and the relative capacitance.
Optionally, the determining a relative dielectric loss value and a relative capacitance of each of the sleeves relative to the other sleeves based on the leakage current includes:
calculating the relative dielectric loss value based on waveform data of the leakage current;
calculating the relative capacitance based on the effective value of the leakage current.
Optionally, the calculating the relative dielectric loss value based on the waveform of the leakage current includes:
performing fourier transform on the waveform data, and extracting a phase value of a fundamental wave of each of the leakage currents according to a transform result;
calculating a phase difference for each of the casings based on the phase values of the other casings;
and carrying out average calculation on the phase differences of a plurality of time points to obtain the relative dielectric loss value of each casing pipe.
Optionally, the calculating the relative capacitance based on the effective value of the leakage current includes:
calculating the current capacitance of each bushing according to the rated voltage and the effective value of the leakage current;
calculating the relative change rate of the capacitance according to the current capacitance and the initial value of the capacitance;
calculating the reference capacitance of each sleeve according to the relative change rate of the capacitance of other sleeves;
and averaging the reference capacitance values at a plurality of time points to obtain the relative capacitance value of each bushing.
There is also provided an on-line monitoring device for a converter transformer substation network side bushing, the on-line monitoring device comprising:
the current acquisition module is configured to synchronously acquire leakage currents of a plurality of bushings under the same reference voltage;
a numerical calculation module configured to determine a relative dielectric loss value and a relative capacitance of each of the casings relative to the other casings based on the leakage current;
and the insulation state judging module is configured to determine the insulation state of the corresponding sleeve according to the relative dielectric loss value and the relative capacitance.
Optionally, the numerical calculation module includes:
an dielectric loss calculation unit for calculating the relative dielectric loss value based on waveform data of the leakage current;
a capacitance calculating unit for calculating the relative capacitance based on the effective value of the leakage current.
Optionally, the dielectric loss calculating unit includes:
a first calculation subunit configured to perform fourier transform on the waveform data, and extract a phase value of a fundamental wave of each of the leakage currents according to a transform result;
a second calculation subunit for calculating the phase difference of each of the casings based on the phase values of the other casings;
and the third calculating subunit is used for carrying out average calculation on the phase differences of a plurality of time points to obtain the relative dielectric loss value of each casing pipe.
Optionally, the capacitance calculating unit includes:
a fourth calculating subunit, configured to calculate a current capacitance of each of the bushings according to a rated voltage and the effective value of the leakage current;
the fifth calculating subunit is used for calculating the relative change rate of the capacitance according to the current capacitance and the initial value of the capacitance;
the sixth calculating subunit is used for calculating the reference capacitance of each sleeve according to the relative change rate of the capacitance of other sleeves;
a seventh calculating subunit, configured to perform an average calculation on the reference capacitance at multiple time points to obtain the relative capacitance of each bushing.
According to the technical scheme, the invention provides the online monitoring method and the online monitoring device for the side casing of the converter transformer substation, and particularly relates to the online monitoring method and the online monitoring device for the side casing of the converter substation, which are used for synchronously collecting the leakage currents of a plurality of casings under the same reference voltage; determining a relative dielectric loss value and a relative capacitance of each casing relative to the other casings based on the leakage current; and determining the insulation state of the corresponding sleeve according to the relative dielectric loss value and the relative capacitance. The insulating state of the sleeve is monitored in an indirect mode, compared with the prior art, the method and the device have the advantages that the leakage current of the sleeve under the condition that a plurality of same-phase running devices are measured, the leakage current and the relative dielectric loss value and the relative capacitance change rate between the devices are measured through mutual reference signals, and the insulating state of the sleeve is judged accordingly.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a flowchart of an online monitoring method for a converter transformer substation lateral casing according to an embodiment of the present application;
FIG. 2 is a phase diagram of the fundamental of the leakage current of 4 bushings of the embodiment of the present application;
FIG. 3 is a phase diagram of the fundamental of the leakage current of an anomalous casing in an embodiment of the application;
fig. 4 is a block diagram of an online monitoring device for a converter transformer substation lateral casing according to an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
Fig. 1 is a flowchart of an online monitoring method for a converter transformer substation lateral casing according to an embodiment of the present application.
Referring to fig. 1, the online monitoring method provided in this embodiment is used for monitoring the insulation state of a bushing on a converter transformer network side of an ac/dc power transmission and transformation system in an indirect manner, and a plurality of bushings are provided on the converter transformer network side, so that the scheme in this embodiment is to implement indirect monitoring by a method for monitoring a plurality of bushings, and the online monitoring method specifically includes the following steps:
and S1, synchronously collecting the leakage currents of the plurality of casings under the same reference voltage.
In specific implementation, leakage currents of all the sleeves under the same reference voltage are synchronously adopted, the sampling precision requirement in synchronous sampling is less than 1 mu s, and a plurality of leakage currents for each sleeve are obtained, wherein the leakage currents comprise information such as waveform data and effective values.
And S2, calculating the relative dielectric loss value and the relative capacitance based on the leakage current.
After obtaining the plurality of leakage currents containing the waveform data, the effective value and other information, calculating according to the waveform data of the leakage currents to obtain the relative dielectric loss value of each casing; while the relative capacity of each bushing is calculated from the effective value of the leakage current.
In this example, the relative dielectric loss value was calculated by the following specific scheme:
first, FFT calculation is performed on the waveform data of the leakage current of each casing, respectively. The FFT is an efficient algorithm for DFT, called Fast Fourier Transform (FFT). Fourier transform is one of the most basic methods in time-frequency domain transform analysis; and extracting the phase value of the fundamental wave from the FFT calculation result of each high voltage bushing.
And then, further calculating according to the phase values of the plurality of casings to calculate a phase difference value and calculate relative dielectric loss. Let us assume θnTo calculate the phase difference of the casing n from the phase value of the fundamental wave of the leakage current of the casing n:
where N is the number of bushings at the same reference voltage.
Finally, for σ at multiple points in timenThe values are calculated by averaging to eliminate measurement errors, the result after averaging being denoted as σn_aveWill be the sigman_aveAs the relative dielectric loss value for the nth casing.
Fig. 2 is a phase value of the fundamental wave of the leakage current of 4 bushings under the same reference voltage, and the figure shows that the phase values of the fundamental waves of all 4 high-voltage bushings are very close under the normal state; as can be seen from fig. 3, the phase of the fundamental wave of the leakage current of the 2 nd casing is abnormal, and based on this, it can be determined that the 2 nd casing has an abnormal relative dielectric loss value.
In addition, the relative capacitance is also calculated in this example by the following scheme:
first, the present capacitance is calculated from the rated voltage of the bushing and the effective value of the leakage current. Since the actual voltage value of the bushing in the operating state is not the nominal voltage value of the bushing, the current capacitance calculated here is not the actual capacitance of the bushing, but only an approximation. In a specific implementation, the effective value of the leakage current can be calculated according to the real part and the imaginary part of the complex value of the fundamental wave in the FFT calculation result, and the square root of the sum of the squares of the real part and the imaginary part is the effective value of the leakage current.
Then, based on the current capacitance (C) calculated at presentn) And initial value of capacitance (C)n_init) Calculating the relative change rate of capacitance C _ Chan. The initial value of capacitance here is the average value of the capacitance calculated over a period of time after the actual operation of the monitoring system. The calculation formula of the relative change rate of the capacitance is as follows:
then, the relative change rate of the capacitance of the plurality of sleeves is comprehensively calculated to obtain the reference capacitance CR of each sleeven. The calculation formula is as follows:
where N is the total number of bushings at the same reference voltage.
Finally, for CR at multiple time pointsnThe values are averaged to further eliminate measurement errors, and the result after averaging the calculated data is denoted as CRn_ave. In particular implementations, the data averaging calculation may be implemented using FIR or IIR filters. And the CR is addedn_aveThe value is taken as the relative capacitance of the nth sleeve.
And S3, determining the insulation state of the sleeve according to the relative dielectric loss value and the relative capacitance.
Considering that in most cases, the number of bushings with changed or unfavorable insulation state will be a small number, after obtaining all the relative dielectric loss values and relative capacitances of the bushings, if there is a significant change in the relative dielectric loss values and relative capacitances of the bushings or one of them, the insulation state can be determined to have changed, thereby realizing real-time monitoring of the insulation state of the bushing on the converter transformer side.
According to the technical scheme, the embodiment provides the online monitoring method for the side casing of the converter transformer substation, and specifically comprises the steps of synchronously collecting leakage currents of a plurality of casings under the same reference voltage; determining a relative dielectric loss value and a relative capacitance of each casing relative to the other casings based on the leakage current; and determining the insulation state of the corresponding sleeve according to the relative dielectric loss value and the relative capacitance. The insulating state of the sleeve is monitored in an indirect mode, compared with the prior art, the method and the device have the advantages that the leakage current of the sleeve under the condition that a plurality of same-phase running devices are measured, the leakage current and the relative dielectric loss value and the relative capacitance change rate between the devices are measured through mutual reference signals, and the insulating state of the sleeve is judged accordingly.
Example two
Fig. 4 is a block diagram of an online monitoring device for a converter transformer substation lateral casing according to an embodiment of the present application.
Referring to fig. 4, the online monitoring device provided in this embodiment is used for monitoring the insulation state of a bushing on the network side of a converter transformer of an ac/dc power transmission and transformation system in an indirect manner, and a plurality of bushings are arranged on the network side of the converter transformer, so that the scheme in this embodiment is to implement indirect monitoring by a method of monitoring a plurality of bushings, and the online monitoring device specifically includes a current obtaining module 10, a numerical calculation module 20, and an insulation state determination module 30.
The current acquisition module is used for synchronously acquiring leakage currents of a plurality of sleeves under the same reference voltage.
In specific implementation, leakage currents of all the casings under the same reference voltage are synchronously sampled, the sampling precision requirement in synchronous sampling is smaller than 1 mu s, and a plurality of leakage currents aiming at each casing are obtained, wherein the leakage currents comprise information such as waveform data and effective values.
The numerical calculation module is used for calculating the relative dielectric loss value and the relative capacitance based on the leakage current. The module comprises a dielectric loss calculation unit 21 and a capacitance calculation unit 22.
After obtaining the plurality of leakage currents containing the waveform data, the effective value and other information, the dielectric loss calculation unit is used for calculating according to the waveform data of the leakage currents to obtain the relative dielectric loss value of each sleeve; the capacitance calculating unit is used for calculating the relative capacity of each sleeve according to the effective value of the leakage current.
The dielectric loss calculation unit comprises a first calculation subunit, a second calculation subunit and a third calculation subunit.
The first calculating subunit is used for respectively carrying out FFT calculation on the waveform data of the leakage current of each casing. The FFT is an efficient algorithm for DFT, called Fast Fourier Transform (FFT). Fourier transform is one of the most basic methods in time-frequency domain transform analysis; and extracting the phase value of the fundamental wave from the FFT calculation result of each high voltage bushing.
The second calculating subunit is used for further calculating phase difference values according to the phase values of the plurality of casings to calculate relative dielectric loss. Let us assume θnTo calculate the phase difference of the casing n from the phase value of the fundamental wave of the leakage current of the casing n:
where N is the number of bushings at the same reference voltage.
A third computing subunit for computing σ at multiple time pointsnThe values are calculated by averaging to eliminate measurement errors, the result after averaging being denoted as σn_aveWill be the sigman_aveAs the relative dielectric loss value for the nth casing.
Fig. 2 is a phase value of the fundamental wave of the leakage current of 4 bushings under the same reference voltage, and the figure shows that the phase values of the fundamental waves of all 4 high-voltage bushings are very close under the normal state; as can be seen from fig. 3, the phase of the fundamental wave of the leakage current of the 2 nd casing is abnormal, and based on this, it can be determined that the 2 nd casing has an abnormal relative dielectric loss value.
Fig. 2 and fig. 3 are used to schematically illustrate the effect of the present technical solution, and the specific content thereof does not affect the content of the technical solution.
The capacitance calculating unit comprises a fourth calculating subunit, a fifth calculating subunit, a sixth calculating subunit and a seventh calculating subunit.
The fourth calculating subunit is used for calculating the current capacitance according to the rated voltage of the bushing and the effective value of the leakage current. Since the low actual voltage value of the bushing in the operating state is not the nominal voltage value of the bushing, the current capacitance calculated here is not the actual capacitance of the bushing but only an approximation. In a specific implementation, the effective value of the leakage current can be calculated according to the real part and the imaginary part of the complex value of the fundamental wave in the FFT calculation result, and the square root of the sum of the squares of the real part and the imaginary part is the effective value of the leakage current.
A fifth calculating subunit for calculating a current capacitance (C) based on the current calculationn) And initial value of capacitance (C)n_init) Calculating the relative change rate of capacitance C _ Chan. The initial value of capacitance here is the average value of the capacitance calculated over a period of time after the actual operation of the monitoring system. The calculation formula of the relative change rate of the capacitance is as follows:
the sixth calculating subunit is used for comprehensively calculating the relative change rates of the capacitances of the multiple sleeves to obtain the reference capacitance CR of each sleeven. The calculation formula is as follows:
where N is the total number of bushings at the same reference voltage.
A seventh computing subunit for computing CR at a plurality of points in timenThe values are averaged to further eliminate measurement errors, and the result after averaging the calculated data is denoted as CRn_ave. In particular implementations, the data averaging calculation may be implemented using FIR or IIR filters. And the CR is addedn_aveThe value is taken as the relative capacitance of the nth sleeve.
And the insulation state judgment module is used for determining the insulation state of the sleeve according to the relative dielectric loss value and the relative capacitance.
Considering that in most cases, the number of bushings with changed or unfavorable insulation state will be a small number, after obtaining all the relative dielectric loss values and relative capacitances of the bushings, if there is a significant change in the relative dielectric loss values and relative capacitances of the bushings or one of them, the insulation state can be determined to have changed, thereby realizing real-time monitoring of the insulation state of the bushing on the converter transformer side.
According to the technical scheme, the embodiment provides the online monitoring method for the side casing of the converter transformer substation, and specifically comprises the steps of synchronously collecting leakage currents of a plurality of casings under the same reference voltage; determining a relative dielectric loss value and a relative capacitance of each casing relative to the other casings based on the leakage current; and determining the insulation state of the corresponding sleeve according to the relative dielectric loss value and the relative capacitance. The insulating state of the sleeve is monitored in an indirect mode, compared with the prior art, the method and the device have the advantages that the leakage current of the sleeve under the condition that a plurality of same-phase running devices are measured, the leakage current and the relative dielectric loss value and the relative capacitance change rate between the devices are measured through mutual reference signals, and the insulating state of the sleeve is judged accordingly.
The embodiments in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, apparatus, or computer program product. Accordingly, embodiments of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
Embodiments of the present invention are described with reference to flowchart illustrations and/or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing terminal to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing terminal to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing terminal to cause a series of operational steps to be performed on the computer or other programmable terminal to produce a computer implemented process such that the instructions which execute on the computer or other programmable terminal provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
While preferred embodiments of the present invention have been described, additional variations and modifications of these embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the embodiments of the invention.
Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or terminal that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or terminal. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or terminal that comprises the element.
The technical solutions provided by the present invention are described in detail above, and the principle and the implementation of the present invention are explained in this document by applying specific examples, and the descriptions of the above examples are only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.
Claims (8)
1. An online monitoring method for a side sleeve of a converter transformer network is characterized by comprising the following steps:
obtaining leakage currents of a plurality of sleeves under the same reference voltage;
determining a relative dielectric loss value and a relative capacitance of each of the sleeves relative to the other sleeves based on the leakage current;
and determining the corresponding insulation state of the sleeve according to the relative dielectric loss value and the relative capacitance.
2. The on-line monitoring method of claim 1, wherein said determining a relative dielectric loss value and a relative capacitance of each of said tubes relative to other of said sleeves based on said leakage current comprises the steps of:
calculating the relative dielectric loss value based on waveform data of the leakage current;
calculating the relative capacitance based on the effective value of the leakage current.
3. The on-line monitoring method of claim 2, wherein said calculating said relative dielectric loss value based on said waveform of said leakage current comprises the steps of:
performing fourier transform on the waveform data, and extracting a phase value of a fundamental wave of each of the leakage currents according to a transform result;
calculating a phase difference for each of the casings based on the phase values of the other casings;
and carrying out average calculation on the phase differences of a plurality of time points to obtain the relative dielectric loss value of each casing pipe.
4. The on-line measuring method of claim 2, wherein said calculating said relative capacitance based on said effective value of said leakage current comprises the steps of:
calculating the current capacitance of each bushing according to the rated voltage and the effective value of the leakage current;
calculating the relative change rate of the capacitance according to the current capacitance and the initial value of the capacitance;
calculating the reference capacitance of each sleeve according to the relative change rate of the capacitance of other sleeves;
and averaging the reference capacitance values at a plurality of time points to obtain the relative capacitance value of each bushing.
5. An on-line monitoring device for a side sleeve of a converter transformer, which is characterized by comprising:
the current acquisition module is configured to synchronously acquire leakage currents of a plurality of bushings under the same reference voltage;
a numerical calculation module configured to determine a relative dielectric loss value and a relative capacitance of each of the casings relative to the other casings based on the leakage current;
and the insulation state judging module is configured to determine the insulation state of the corresponding sleeve according to the relative dielectric loss value and the relative capacitance.
6. The on-line monitoring device of claim 5, wherein the numerical calculation module comprises:
an dielectric loss calculation unit for calculating the relative dielectric loss value based on waveform data of the leakage current;
a capacitance calculating unit for calculating the relative capacitance based on the effective value of the leakage current.
7. The on-line monitoring device of claim 6, wherein the dielectric loss calculation unit comprises:
a first calculation subunit configured to perform fourier transform on the waveform data, and extract a phase value of a fundamental wave of each of the leakage currents according to a transform result;
a second calculation subunit for calculating the phase difference of each of the casings based on the phase values of the other casings;
and the third calculating subunit is used for carrying out average calculation on the phase differences of a plurality of time points to obtain the relative dielectric loss value of each casing pipe.
8. The on-line measuring device of claim 6, wherein the capacitance calculating unit comprises:
a fourth calculating subunit, configured to calculate a current capacitance of each of the bushings according to a rated voltage and the effective value of the leakage current;
the fifth calculating subunit is used for calculating the relative change rate of the capacitance according to the current capacitance and the initial value of the capacitance;
the sixth calculating subunit is used for calculating the reference capacitance of each sleeve according to the relative change rate of the capacitance of other sleeves;
a seventh calculating subunit, configured to perform an average calculation on the reference capacitance at multiple time points to obtain the relative capacitance of each bushing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011569048.6A CN112946515A (en) | 2020-12-25 | 2020-12-25 | Online monitoring method and device for converter transformer network side sleeve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011569048.6A CN112946515A (en) | 2020-12-25 | 2020-12-25 | Online monitoring method and device for converter transformer network side sleeve |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112946515A true CN112946515A (en) | 2021-06-11 |
Family
ID=76236049
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011569048.6A Pending CN112946515A (en) | 2020-12-25 | 2020-12-25 | Online monitoring method and device for converter transformer network side sleeve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112946515A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117434407A (en) * | 2023-12-20 | 2024-01-23 | 南京中鑫智电科技有限公司 | Time-frequency domain feature fusion converter transformer valve side sleeve insulation analysis method and system |
| CN117686861A (en) * | 2024-02-04 | 2024-03-12 | 南京中鑫智电科技有限公司 | Method and system for monitoring insulation state of converter transformer valve side sleeve with multi-stage reference |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104142422A (en) * | 2013-05-08 | 2014-11-12 | 伍俊 | Transformation substation leakage current and capacitive current online monitoring management system and working method thereof |
| CN107102245A (en) * | 2017-06-09 | 2017-08-29 | 云南电网有限责任公司电力科学研究院 | Deformation of transformer winding and condenser bushing failure detector and method |
-
2020
- 2020-12-25 CN CN202011569048.6A patent/CN112946515A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104142422A (en) * | 2013-05-08 | 2014-11-12 | 伍俊 | Transformation substation leakage current and capacitive current online monitoring management system and working method thereof |
| CN107102245A (en) * | 2017-06-09 | 2017-08-29 | 云南电网有限责任公司电力科学研究院 | Deformation of transformer winding and condenser bushing failure detector and method |
Non-Patent Citations (2)
| Title |
|---|
| ALBH81462: "《均值替代》", 《CSDN》 * |
| 陈子良: "《容性设备带电检测技术应用及在线监测装置研究》", 《万方》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117434407A (en) * | 2023-12-20 | 2024-01-23 | 南京中鑫智电科技有限公司 | Time-frequency domain feature fusion converter transformer valve side sleeve insulation analysis method and system |
| CN117434407B (en) * | 2023-12-20 | 2024-02-20 | 南京中鑫智电科技有限公司 | Time-frequency domain feature fusion converter transformer valve side sleeve insulation analysis method and system |
| CN117686861A (en) * | 2024-02-04 | 2024-03-12 | 南京中鑫智电科技有限公司 | Method and system for monitoring insulation state of converter transformer valve side sleeve with multi-stage reference |
| CN117686861B (en) * | 2024-02-04 | 2024-04-23 | 南京中鑫智电科技有限公司 | Method and system for monitoring insulation state of converter transformer valve side sleeve with multi-stage reference |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Gazzana et al. | An integrated technique for fault location and section identification in distribution systems | |
| CN108957244B (en) | Single-phase earth fault line selection positioning method for distribution network main station | |
| CN108107321B (en) | Fault waveform comparison method for power system | |
| CN106093593B (en) | Condenser type electric power equipment dielectric loss online test method and system | |
| CN102279341B (en) | Cage asynchronous motor rotor broken-bar fault detection method based on electronic stability program rotation invariant technology (ESPRIT) and pattern search algorithm (PSA) | |
| WO1997008562A1 (en) | Method of locating a single-phase ground fault in a power distribution network | |
| CN106597229B (en) | The working method of 35kV or more transformer equipment insulated on-line monitoring system | |
| CN111007435B (en) | Monitoring method, device and equipment for analyzing transformer fault based on resistance-capacitance component | |
| CN112946515A (en) | Online monitoring method and device for converter transformer network side sleeve | |
| WO2015160616A1 (en) | Transformer parameter estimation using terminal measurements | |
| CN114879085B (en) | Single-phase earth fault identification method and device, electronic equipment and medium | |
| Taheri et al. | Single-end current-based algorithm for fault location in series capacitor compensated transmission lines | |
| Patel et al. | Differential voltage‐based fault detection during power swing | |
| CN110618338B (en) | Electric energy quality transient measurement method, device and equipment | |
| CN110007198A (en) | A kind of novel singlephase earth fault starting method | |
| CN114002475B (en) | Online monitoring method for resistive current of lightning arrester | |
| CN107179476B (en) | Distribution network fault distance measurement method | |
| CN109375048B (en) | Power transmission line parameter identification method and device based on fault recording data | |
| CN115219787A (en) | Power grid phasor movement measurement method, system and medium based on improved matrix bundle | |
| CN115728700A (en) | Transient frequency response testing method for direct-current voltage transformer | |
| Lu et al. | Generalized phasor estimation method based on DFT with DC offset mitigation | |
| CN115313329A (en) | Frequency band range selection method for rapid traveling wave protection and related device | |
| CN112485523B (en) | Method for judging harmonic voltage measurement distortion | |
| CN111929630B (en) | Method and device for detecting saturation of current transformer | |
| CN109507531B (en) | Power distribution network single-phase grounding line selection method, system, device and readable storage medium |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210611 |
|
| RJ01 | Rejection of invention patent application after publication |