CN113093085A - Method and device for detecting secondary circuit fault of station domain current transformer - Google Patents
Method and device for detecting secondary circuit fault of station domain current transformer Download PDFInfo
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Abstract
The invention relates to the technical field of secondary circuit detection of a current transformer, in particular to a method and a device for detecting a fault of a secondary circuit of a station-domain current transformer, wherein the method comprises the steps of acquiring basic identification data of the secondary circuit of the current transformer; judging whether the distance of the comprehensive characteristic quantity is larger than a conventional value of the distance of the comprehensive characteristic quantity; judging whether the current distance is larger than a current distance conventional value or not, judging the current distance of a previous-stage device, and determining the position of a short circuit fault of a secondary circuit of the current transformer; and judging whether the resistance distance is larger than a conventional value of the resistance distance or not, judging the resistance distance of each single-phase loop, and determining the disconnection position of the secondary loop of the current transformer. The invention combines the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic to carry out primary identification on the fault type of the secondary circuit, and compares the electrical quantity data of devices at all levels to find the fault position of the circuit in time by utilizing the characteristics of different winding acquisition of the homology data of the current transformer and the serial connection of the current secondary circuit, thereby realizing the effective detection of the fault of the current secondary circuit.
Description
Technical Field
The invention relates to the technical field of secondary circuit detection of a current transformer, in particular to a method and a device for detecting a fault of a secondary circuit of a substation-domain current transformer.
Background
The current transformer secondary loop is used as an important link of power grid current sampling, secondary sampling current of the current transformer is transmitted to various secondary devices, the current transformer secondary sampling current is a main basis of power grid automation, protection and system control, particularly in the protection link, the current sampling is used as an important calculated amount for power grid fault judgment, and the correctness of sampling transmission has great significance for the correct action of a protection device. The conventional sampling secondary loop adopts a secondary cable, the middle of the secondary cable is connected with each protection and automatic device screen cabinet through a local terminal box, the secondary cable is connected with the screen cabinet through a current terminal, the number of intermediate links is large, the connection is complex, the transmission path is long, and meanwhile most of the cables are laid in hidden engineering and are not exposed obviously. In actual operation, once secondary sampling of the current transformer is problematic, fault location is difficult, and misoperation of secondary equipment is easily caused. The main reasons for incorrect operation caused by the secondary circuit of the current transformer are: the current transformer plug-in board has the advantages of insulation damage grounding, poor circuit contact, short circuit, open circuit, secondary sampling distortion, inconsistent current transformer plug-in transmission characteristics of the protection devices on two sides and the like.
At present, the current transformer secondary circuit detection mainly takes infrared temperature measurement and current transformer secondary load off-line detection as main parts, and is carried out regularly by combining secondary equipment inspection and routing inspection work, so that the secondary circuit fault cannot be found in time. Meanwhile, after a secondary circuit fault of the current transformer occurs, although secondary equipment such as relay protection and the like can send an alarm by combining with discrimination logic, on-site processing can depend on manual detection and troubleshooting, and how to perform fault identification and detection on secondary sampling of the current transformer cannot be effectively identified, detected and positioned.
Disclosure of Invention
The invention provides a station domain current transformer secondary circuit fault detection method and device, overcomes the defects of the prior art, and can effectively solve the problems that the secondary circuit fault cannot be found in time and cannot be positioned in the detection of the secondary circuit of the current transformer.
One of the technical schemes of the invention is realized by the following measures: a method for detecting a fault of a secondary circuit of a station domain current transformer comprises the following steps:
acquiring basic identification data of a secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
acquiring the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is greater than a conventional value of the comprehensive characteristic quantity distance, and respectively judging the current distance and the resistance distance in response to yes;
judging whether the current distance is greater than a current distance conventional value or not, and determining the position of the short circuit fault of the secondary circuit of the current transformer by judging whether the current distance of the previous-stage device is greater than the current distance conventional value or not in response to the judgment;
and judging whether the resistance distance is greater than a conventional value of the resistance distance, and determining the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distances of the single-phase circuits are greater than the conventional value of the resistance distances in response.
The following is further optimization or/and improvement of the technical scheme of the invention:
the above-mentioned comprehensive characteristic quantity distance of obtaining the current characteristic, resistance characteristic includes:
obtaining two groups of secondary circuit electric quantity data TA ═ a of the current transformer according to the basic identification data of the secondary circuit of the current transformer1，a2，a3，…，an}，TB＝{b1，b2，b3，…，bnIn which a isn、bnData points of TA and TB at the nth moment;
obtaining a current characteristic quantity I (a)i，bi) And a resistance characteristic quantity R (a)i，bi)；
According to the current characteristic and the resistance characteristic, obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic through the following formula:
wherein, TMFD (a)i,bi)＝ωR·R+ωII, ω is a weight coefficient, and ωR+ωI＝1。
Above-mentioned judging current distance is greater than current distance conventional value, responds to then, and then whether current distance through judging last level of device is greater than current distance conventional value, confirms current transformer secondary circuit short circuit fault position, includes:
judging whether the current distance is larger than a conventional current distance value or not;
judging whether the current distance of the previous-stage device is larger than a conventional current distance value or not in response to the current;
if not, determining that the short-circuit fault position of the secondary circuit of the current transformer is the next secondary circuit of the device;
and if so, determining whether the current data of each stage of device connected in series in the loop is judged to be finished, if so, determining that the position of the short circuit fault of the secondary loop of the current transformer is the root of the current transformer, and if not, continuously judging the current distance of the previous stage of device of the device.
Above-mentioned judge whether resistance distance is greater than resistance distance conventional value, respond to then, through judging whether the resistance distance of each single-phase circuit is greater than resistance distance conventional value, confirm current transformer secondary circuit broken string position, include:
judging whether the resistance distance is larger than a conventional value of the resistance distance;
judging whether the resistance distances of all phase loops of the secondary loop of the current transformer are larger than a conventional value of the resistance distances or not in response;
responding to the judgment result, wherein the one-phase loop with the resistance distance larger than the conventional value is the disconnection position of the secondary loop of the current transformer;
and responding to the condition, and setting the secondary circuit disconnection position of the current transformer to be N circuit disconnection.
The above-mentioned basic identification data who obtains current transformer secondary circuit includes:
collecting current data of a secondary loop of a current transformer and voltage data of the secondary loop of the current transformer;
and determining the resistance data of the secondary circuit of the current transformer according to the current data of the secondary circuit of the current transformer and the voltage data of the secondary circuit of the current transformer.
The second technical scheme of the invention is realized by the following measures: a station domain current transformer secondary circuit fault detection device comprises:
the data acquisition unit is used for acquiring basic identification data of the secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
the circuit fault preliminary judgment unit is used for obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is larger than a conventional value of the comprehensive characteristic quantity distance, and judging the current distance and the resistance distance respectively in response to yes;
the circuit short-circuit fault judging unit judges whether the current distance is greater than a current distance conventional value, and determines the position of a secondary circuit short-circuit fault of the current transformer by judging whether the current distance of the previous-stage device is greater than the current distance conventional value in response to the current distance;
and the circuit disconnection fault judgment unit judges whether the resistance distance is greater than a conventional resistance distance value or not, and determines the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distance of each single-phase circuit is greater than the conventional resistance distance value or not in response to the judgment.
The invention obtains the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic through the basic identification data of the secondary circuit of the current transformer, preliminarily identifies the fault type of the secondary circuit by combining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, and further compares the electric quantity data of devices at all levels to find the fault position of the circuit in time by utilizing the characteristics of different winding acquisition of the homology data of the current transformer and the serial connection of the secondary circuit of the current transformer, thereby realizing the effective detection of the fault of the secondary circuit of the current transformer.
Drawings
FIG. 1 is a process flow diagram of example 1 of the present invention.
FIG. 2 is a flowchart of the method of example 2 of the present invention.
FIG. 3 is a flowchart of the method of example 3 of the present invention.
Fig. 4 is a schematic circuit diagram of a typical current transformer configuration and secondary circuit in embodiment 4 of the present invention.
Fig. 5 is a schematic diagram of a fault current waveform of a set a of main transformer current circuits of a certain station in embodiment 4 of the present invention.
Fig. 6 is a schematic diagram showing a comparison of current waveforms of two main transformer current loops of a station in embodiment 4 of the present invention.
Fig. 7 is a schematic diagram illustrating comparison of waveforms of self-generated zero-sequence currents of two main transformer current circuits of a station in embodiment 4 of the present invention.
Fig. 8 is a schematic diagram comparing normal current waveforms of two main transformer current loops of a station in embodiment 4 of the present invention.
FIG. 9 is a schematic structural view of an apparatus according to example 5 of the present invention.
Detailed Description
The present invention is not limited by the following examples, and specific embodiments may be determined according to the technical solutions and practical situations of the present invention.
The invention is further described with reference to the following examples and figures:
example 1: as shown in fig. 1, the present embodiment discloses a station-domain current transformer secondary circuit fault detection method, including:
step S101, acquiring basic identification data of a secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
step S102, obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is larger than a conventional value of the comprehensive characteristic quantity distance, and judging the current distance and the resistance distance respectively in response to yes;
step S103, judging whether the current distance is larger than a current distance conventional value, and determining the short-circuit fault position of a secondary circuit of the current transformer by judging whether the current distance of the previous-stage device is larger than the current distance conventional value in response to the judgment;
and step S104, judging whether the resistance distance is greater than a conventional resistance distance value, and determining the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distance of each single-phase circuit is greater than the conventional resistance distance value in response.
The embodiment of the invention discloses a station domain current transformer secondary circuit fault detection method, which obtains the comprehensive characteristic quantity distance of current characteristics and resistance characteristics through the basic identification data of a current transformer secondary circuit, preliminarily identifies the fault type of the secondary circuit by combining the comprehensive characteristic quantity distance of the current characteristics and the resistance characteristics, further utilizes the characteristics of different winding acquisition of current transformer homology data and the serial connection of the current transformer secondary circuit, compares the electrical quantity data of devices at all levels to find the fault position of the circuit in time, thereby realizing the effective detection of the current transformer secondary circuit fault, ensuring the reliability of the circuit, having important significance for ensuring the normal and reliable operation of a secondary system, simultaneously providing a technical reference basis for the state maintenance of secondary equipment, accurately positioning the dangerous hidden danger and guiding the development of maintenance work.
In step S101, obtaining basic identification data of the secondary circuit of the current transformer includes:
step S1011, collecting current data of a secondary loop of the current transformer and voltage data of the secondary loop of the current transformer;
step S1012, determining the secondary loop resistance data of the current transformer according to the secondary loop current data of the current transformer and the secondary loop voltage data of the current transformer.
The determining of the fault of the secondary circuit of the current transformer in the steps S102 to S104 includes a first judgment and a second judgment, and specifically includes:
A. the primary judgment is carried out, wherein the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic is calculated, and whether a fault exists in the current secondary circuit or not is primarily judged according to the comprehensive characteristic quantity distance; after the initial judgment, if a fault exists, the judgment is carried out again.
B. And judging whether the current distance is larger than a current distance conventional value (namely whether the current characteristic is abnormal) and whether the resistance distance is larger than a resistance distance conventional value (namely whether the resistance characteristic is abnormal), and determining whether the circuit short-circuit fault or the circuit disconnection fault exists.
C. When the circuit short circuit fault is judged, calculating the fault phase data (namely the current distance of the device) of the primary device according to the series connection characteristic of the field actual current circuit until finding out the normal distance calculation result and judging the next secondary circuit of the device corresponding to the normal calculation result at the fault position; if the current sampling data of all levels of devices connected in series in the circuit are abnormal after calculation, the measurement and measurement circuit can be compared to judge that the fault position is at the root of the current transformer. Because the probability that each loop of the current transformer breaks down simultaneously is very low, if the metering and measuring loop is abnormal, the problem of the primary equipment of the current transformer body can be judged.
D. And when the circuit disconnection fault is judged, judging whether the resistance distance of each single-phase circuit is larger than a conventional value of the resistance distance, if the resistance characteristics of the single-phase circuit are abnormal in the three-phase current, judging that the circuit disconnection of the phase exists, and if the resistance characteristics of the three-phase circuit are abnormal, judging that the circuit disconnection of the N circuits exists.
Example 2: as shown in fig. 2, the embodiment discloses a station-domain current transformer secondary circuit fault detection method, which includes:
step S201, acquiring basic identification data of a secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
step S202, obtaining two groups of secondary circuit electric quantity data TA ═ a of the current transformer according to the basic identification data of the secondary circuit of the current transformer1，a2，a3，…，an}，TB＝{b1，b2，b3，…，bn}；
Wherein a isn、bnData points of TA and TB at the nth moment;
it should be noted here that the data of the electrical quantity of the secondary circuit of the current transformer is composed of a series of data points which change with time, i.e. T ═ { a ═ a1，A2，…Ai，…，AnThe ith data point can be represented as Ai＝(Ui，Ii，ti) Wherein U isi、IiCurrent transformer secondary loop current data and current transformer secondary loop voltage data, t, as data pointsiIs the timestamp information for that data point.
Step S203, obtaining a current characteristic I (a)i，bi) And a resistance characteristic R (a)i，bi)；
The current characteristic I (a) herei，bi)＝dist(Iai，(Ibi，Ibi-1，Ibi+1) Represents the current distance between two points on the two sets of electrical quantities;
the resistance characteristic R (a) herei，bi)＝dist(Rai，(Rbi，Rbi-1，Rbi+1) Represents the resistive distance of two points on two sets of electrical quantities.
Step S204, obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic according to the following formula:
wherein, TMFD (a)i,bi)＝ωR·R+ωII, ω is a weight coefficient, and ωR+ωIThe weight coefficient can be adjusted according to specific needs, namely 1;
step S205, judging whether the distance of the comprehensive characteristic quantity is larger than a conventional value of the distance of the comprehensive characteristic quantity, and respectively judging the current distance and the resistance distance in response to yes;
step S206, judging whether the current distance is larger than a current distance conventional value, and determining the short-circuit fault position of the secondary circuit of the current transformer by judging whether the current distance of the previous-stage device is larger than the current distance conventional value in response to the judgment;
and step S207, judging whether the resistance distance is greater than a conventional resistance distance value, and determining the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distance of each single-phase circuit is greater than the conventional resistance distance value in response.
Example 3: as shown in fig. 3, the embodiment discloses a station-domain current transformer secondary circuit fault detection method, which includes:
step S301, acquiring basic identification data of a secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
step S302, obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is larger than a conventional value of the comprehensive characteristic quantity distance, and respectively judging the current distance and the resistance distance in response to yes;
step S303, judging whether the current distance is larger than a conventional current distance value;
step S304, in response to yes, judging whether the current distance of the previous-stage device is larger than a conventional current distance value;
step S305, in response to the judgment, determining that the short-circuit fault position of the secondary circuit of the current transformer is the next secondary circuit of the device;
step S306, determining whether the current data of each stage of device connected in series in the loop are judged completely or not in response, determining that the position of the short-circuit fault of the secondary loop of the current transformer is the root of the current transformer in response, and continuously judging the current distance of the previous stage of device of the device in response to the fact that the short-circuit fault of the secondary loop of the current transformer is not judged;
step S307, judging whether the resistance distance is larger than a conventional value of the resistance distance;
step S308, responding to the above, judging whether the resistance distances of all phase loops of the secondary loop of the current transformer are all larger than the conventional resistance distance value;
step S309, responding to the judgment result, wherein the one-phase loop with the resistance distance larger than the conventional value is the disconnection position of the secondary loop of the current transformer;
and step S3010, in response, setting the disconnection position of the secondary circuit of the current transformer to be N-circuit disconnection.
The steps S303 to S306 are configured to determine whether the fault type is a short circuit again after the primary determination that the secondary circuit of the current transformer has a fault, and locate a position where the short circuit occurs.
The steps S307 to S3010 are configured to determine whether the fault type is a circuit disconnection again after the primary determination that the secondary circuit of the current transformer has a fault, and locate a position where the circuit disconnection occurs.
Example 4: when the embodiment of the invention is used for configuration and a secondary circuit of a typical current transformer, the fault detection process of the invention is as follows:
the preparation for acquiring the basic identification data of the secondary circuit of the current transformer by taking 220 kilovolt line interval as an example is as follows: generally configuring 6 groups of current transformers at 220 KV line intervals, namely protection A, protection B, bus differential A, bus differential B, measurement and metering, wherein due to the particularity of a current loop of the current transformers, fault recording and stable control are respectively connected behind a protection secondary loop in series, and a synchronous phasor measurement PMU is connected behind a measurement loop in series; the left side of fig. 4 is a typical configuration of the line interval current transformer, and it can be seen that, based on the homology consideration, for the same primary source, 6 sets of current magnitude data information are collected at the line interval; the right side of the drawing in fig. 4 is a secondary circuit diagram of a first group of current transformers, the head ends and the tail ends of the single-phase current transformers are both led into the local cabinet by the root of the current transformer and are connected into the terminal block, and the head ends and the tail ends of the single-phase current transformers are connected through the secondary terminal block; the head end of the current transformer is led out through the terminal strip, then led into a line protection A set of screen cabinet in the protection chamber through a secondary cable, and led out to a fault recording A and a stability control A through the secondary cable after entering the protection A set through the terminal strip. The tail ends of the current transformers are connected in parallel and then are led into a small protection chamber as N, meanwhile A, B, C three-phase current is connected into an N line after being connected in parallel at the tail end of a loop, and the grounding point of the N line is connected to a secondary grounding grid.
Then, station-domain secondary circuit fault detection is performed according to the steps in the embodiment 3, it needs to be described that N circuit disconnection is special, when primary equipment has no fault, the sum of three-phase vectors of secondary sampling current A, B, C is 0 under an ideal condition, and the N circuit has no current; under the condition of primary equipment failure, the vector sum of three-phase currents is not 0, the self-generated zero-sequence current does not flow out of a loop under the condition of N-loop disconnection, and zero-sequence components in secondary current have no circulation path, so that the self-generated zero-sequence current synthesized by the three-phase currents is almost 0, the self-generated zero-sequence current cannot be acquired by secondary equipment, and the three-phase sampling waveform is distorted. In an actual operation plant station, due to the influence of external factors such as secondary equipment operation environment, grounding grid and electromagnetic environment interference, the actual voltage of an grounding point is not strictly equal to 0, at the moment, three-phase current neutral point drift is caused after the N circuit is disconnected, the voltage of the N line to ground is neutral point drift voltage, the voltage is greatly influenced by the operation environment but is generally not 0, at the moment, due to the superposition influence of the N line neutral point drift voltage, the circuit measurement voltage is generally increased, and the three-phase current circuit measurement resistance is increased. Therefore, for the N-loop broken line, the resistance value of the three-phase current loop can be compared to be used as the N-loop broken line comprehensive fault characteristic quantity identification method when primary equipment normally operates and no fault exists.
Taking the grounding short circuit of the current secondary circuit as an example, the detection result under the condition of the circuit fault is verified, and the specific steps are as follows:
FIG. 5 shows the extracted fault waveform data of a set of main transformer current loops A of a certain station, wherein the amplitude of the fault waveform data is the phase A current waveform with the minimum amplitude, the phase C waveform with the minimum amplitude, and the phase B current waveform with the maximum amplitude, wherein the fault phase is the phase A. When a fault occurs, the winding loop of the A set of phase current transformer of the main transformer protection A of a certain station is grounded and forms shunt with the current N, so that the amplitude of the A phase current is reduced. In fig. 6, the upper part of the graph shows the comparison between the abnormal current of the a phase (the gray current waveform with the minimum amplitude value in the graph) in the a set of devices and the normal current of the a phase (the black current waveform with the maximum amplitude value in the graph) in the B set of devices, and the lower histogram shows the calculation result of the multi-feature-quantity two-point distance algorithm based on the time series, from which it can be seen that the maximum calculation of the current feature I distance is 50. In the figure 7, the upper part is the comparison between the self-generated zero-sequence current (the current waveform with the maximum amplitude value in the figure) of the set A of devices and the self-generated zero-sequence current (the current waveform with the minimum amplitude value in the figure) of the set B of devices, and the lower part is the calculation result of a multi-characteristic-quantity two-point distance algorithm based on a time sequence, so that the maximum calculation of the characteristic distance of the self-generated zero-sequence current can be seen to be 121.
In order to further verify the effectiveness of the detection method, the waveform data of the normal current secondary circuit of the transformer substation is extracted, the upper part of the attached drawing 8 is the comparison of the normal current waveform of the phase A of the A set of device (grey current waveform in the drawing) and the normal current waveform of the phase A of the B set of device (black current waveform in the drawing), and the lower histogram is the calculation result of the distance between two groups of phase A currents. As can be seen from the figure, the difference in the phase current waveforms of the two sets of components is not significant, and the distance calculation result fluctuates within a normal range (the current characteristic distance calculation result is 5). In fig. 8, the two groups of phase-A currents have only slight difference at the maximum value, and the distance calculation result also obviously distinguishes the characteristics. The calculation result shows that the method can effectively judge the abnormal sampling data, provides an effective detection, identification and inspection method for the secondary circuit fault of the current transformer, and particularly has higher sensitivity for slight waveform abnormal data.
Example 5: as shown in fig. 9, the present embodiment discloses a station area current transformer secondary circuit fault detection apparatus, including:
the data acquisition unit is used for acquiring basic identification data of the secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
the circuit fault preliminary judgment unit is used for obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is larger than a conventional value of the comprehensive characteristic quantity distance, and judging the current distance and the resistance distance respectively in response to yes;
the circuit short-circuit fault judging unit judges whether the current distance is greater than a current distance conventional value, and determines a secondary circuit fault link of the current transformer by judging whether the current distance of the previous-stage device is greater than the current distance conventional value in response to the current distance;
and the circuit disconnection fault judgment unit judges whether the resistance distance is greater than a conventional resistance distance value or not, and determines the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distance of each single-phase circuit is greater than the conventional resistance distance value or not in response to the judgment.
In the above technical solution, the process of acquiring current data of the secondary circuit of the current transformer and voltage data of the secondary circuit of the current transformer in the data acquisition unit specifically includes:
the current transformer secondary circuit current data can be based on the existing relay protection equipment on-line monitoring and analysis application system, and the monitoring and analysis of the operation condition and the operation state of the secondary equipment are realized. The application system comprises functions of collecting and processing real-time information of the station control layer protection equipment, calling protection professional information, calling fault recording and the like, wherein the collection of the real-time information of the station control layer protection equipment can realize the collection of current analog quantity information measured by secondary equipment. Meanwhile, the application system also supports calling of the recording files of the relay protection device and the fault recording device, does not support continuous acquisition of secondary equipment current analog quantity information during construction of part of application systems, and only supports single-point real-time information acquisition. Because the secondary sampling fault identification and detection of the current transformer has no special requirement on the real-time property of the sampled data, the remote wave recording can also meet the detection and analysis requirements. The current data of the secondary loop of the current transformer acquired by stability control is provided by a real-time database of a safety and stability control management system, and synchronous phasor measurement PMU, measurement and control and metering data can be acquired by combining a field automation and a metering professional data terminal. When the field measurement and metering loop does not meet the acquisition requirement, offline scattered data sent by a measurement and metering system can be used as an auxiliary screening data source for fault identification and detection, and data of a protection loop is used as a final detection and analysis source.
The current transformer secondary circuit voltage data is based on the requirement of current transformer secondary sampling fault detection, a special circuit voltage measuring device is additionally arranged on a local cabinet current transformer circuit terminal to measure the current transformer secondary circuit three-phase voltage and the N circuit voltage in real time, a GPS time synchronization function is provided, the measured data is uploaded remotely, and meanwhile, the voltage data needs to be provided with time coordinates to meet the requirement of data identification and analysis.
The storage medium may include, but is not limited to: u disk, read-only memory, removable hard disk, magnetic or optical disk, etc. various media capable of storing computer programs.
Embodiment 7, this embodiment discloses an electronic device, which includes a processor and a memory, where the memory stores a computer program, and the computer program is loaded and executed by the processor to implement the station-domain current transformer secondary circuit fault detection method.
The electronic equipment further comprises transmission equipment and input and output equipment, wherein the transmission equipment and the input and output equipment are both connected with the processor.
The above technical features constitute the best embodiment of the present invention, which has strong adaptability and best implementation effect, and unnecessary technical features can be increased or decreased according to actual needs to meet the requirements of different situations.
Claims (9)
1. A station domain current transformer secondary circuit fault detection method is characterized by comprising the following steps:
acquiring basic identification data of a secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
acquiring the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is greater than a conventional value of the comprehensive characteristic quantity distance, and respectively judging the current distance and the resistance distance in response to yes;
judging whether the current distance is greater than a current distance conventional value or not, and determining the position of the short circuit fault of the secondary circuit of the current transformer by judging whether the current distance of the previous-stage device is greater than the current distance conventional value or not in response to the judgment;
and judging whether the resistance distance is greater than a conventional value of the resistance distance, and determining the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distances of the single-phase circuits are greater than the conventional value of the resistance distances in response.
2. The station-domain current transformer secondary circuit fault detection method according to claim 1, wherein the obtaining of the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic comprises:
obtaining two groups of secondary circuit electric quantity data TA ═ a of the current transformer according to the basic identification data of the secondary circuit of the current transformer1，a2，a3，…，an}，TB＝{b1，b2，b3，…，bnIn which a isn、bnData points of TA and TB at the nth moment;
obtaining a current characteristic quantity I (a)i，bi) And a resistance characteristic quantity R (a)i，bi)；
According to the current characteristic and the resistance characteristic, obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic through the following formula:
wherein, TMFD (a)i,bi)＝ωR·R+ωII, ω is a weight coefficient, and ωR+ωI＝1。
3. The station-domain current transformer secondary circuit fault detection method according to claim 1 or 2, wherein the judging whether the current distance is greater than a current distance regular value, and in response, determining the current transformer secondary circuit short-circuit fault position by judging whether the current distance of the previous-stage device is greater than the current distance regular value comprises:
judging whether the current distance is larger than a conventional current distance value or not;
judging whether the current distance of the previous-stage device is larger than a conventional current distance value or not in response to the current;
if not, determining that the short-circuit fault position of the secondary circuit of the current transformer is the next secondary circuit of the device;
and if so, determining whether the current data of each stage of device connected in series in the loop is judged to be finished, if so, determining that the position of the short circuit fault of the secondary loop of the current transformer is the root of the current transformer, and if not, continuously judging the current distance of the previous stage of device of the device.
4. The station-area current transformer secondary circuit fault detection method according to claim 1 or 2, wherein the judging whether the resistance distance is greater than a resistance distance conventional value, and in response, determining the disconnection position of the current transformer secondary circuit by judging whether the resistance distance of each single-phase circuit is greater than the resistance distance conventional value comprises:
judging whether the resistance distance is larger than a conventional value of the resistance distance;
judging whether the resistance distances of all phase loops of the secondary loop of the current transformer are larger than a conventional value of the resistance distances or not in response;
responding to the judgment result, wherein the one-phase loop with the resistance distance larger than the conventional value is the disconnection position of the secondary loop of the current transformer;
and responding to the condition, and setting the secondary circuit disconnection position of the current transformer to be N circuit disconnection.
5. The station-domain current transformer secondary circuit fault detection method according to claim 3, wherein the judging whether the resistance distance is greater than a resistance distance conventional value, and in response thereto, determining the disconnection position of the current transformer secondary circuit according to the judging whether the resistance distance of each single-phase circuit is greater than the resistance distance conventional value comprises:
judging whether the resistance distance is larger than a conventional value of the resistance distance;
judging whether the resistance distances of all phase loops of the secondary loop of the current transformer are larger than a conventional value of the resistance distances or not in response;
responding to the judgment result, wherein the one-phase loop with the resistance distance larger than the conventional value is the disconnection position of the secondary loop of the current transformer;
and responding to the condition, and setting the secondary circuit disconnection position of the current transformer to be N circuit disconnection.
6. The station-domain current transformer secondary circuit fault detection method according to any one of claims 1 to 5, wherein the acquiring of the basic identification data of the current transformer secondary circuit comprises:
collecting current data of a secondary loop of a current transformer and voltage data of the secondary loop of the current transformer;
and determining the resistance data of the secondary circuit of the current transformer according to the current data of the secondary circuit of the current transformer and the voltage data of the secondary circuit of the current transformer.
7. The utility model provides a station territory current transformer secondary circuit fault detection device which characterized in that includes:
the data acquisition unit is used for acquiring basic identification data of the secondary circuit of the current transformer, wherein the basic identification data comprises current data of the secondary circuit of the current transformer, voltage data of the secondary circuit of the current transformer and resistance data of the secondary circuit of the current transformer;
the circuit fault preliminary judgment unit is used for obtaining the comprehensive characteristic quantity distance of the current characteristic and the resistance characteristic, judging whether the comprehensive characteristic quantity distance is larger than a conventional value of the comprehensive characteristic quantity distance, and judging the current distance and the resistance distance respectively in response to yes;
the circuit short-circuit fault judging unit judges whether the current distance is greater than a current distance conventional value, and determines the position of a secondary circuit short-circuit fault of the current transformer by judging whether the current distance of the previous-stage device is greater than the current distance conventional value in response to the current distance;
and the circuit disconnection fault judgment unit judges whether the resistance distance is greater than a conventional resistance distance value or not, and determines the disconnection position of the secondary circuit of the current transformer by judging whether the resistance distance of each single-phase circuit is greater than the conventional resistance distance value or not in response to the judgment.
8. A storage medium having stored thereon a computer program readable by a computer, the computer program being arranged to perform the station domain current transformer secondary circuit fault detection method according to any one of claims 1 to 6 when executed.
9. An electronic device, comprising a processor and a memory, wherein the memory has stored therein a computer program, the computer program being loaded and executed by the processor to implement the station-domain current transformer secondary loop fault detection method according to any one of claims 1 to 6.
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