CN115327371A - Method for diagnosing state time point of medium-voltage switch and related device - Google Patents
Method for diagnosing state time point of medium-voltage switch and related device Download PDFInfo
- Publication number
- CN115327371A CN115327371A CN202211269469.6A CN202211269469A CN115327371A CN 115327371 A CN115327371 A CN 115327371A CN 202211269469 A CN202211269469 A CN 202211269469A CN 115327371 A CN115327371 A CN 115327371A
- Authority
- CN
- China
- Prior art keywords
- data
- point
- time
- calculating
- length
- 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 42
- 238000005070 sampling Methods 0.000 claims abstract description 62
- 230000008859 change Effects 0.000 claims abstract description 48
- 238000004364 calculation method Methods 0.000 claims description 7
- 238000004458 analytical method Methods 0.000 claims description 6
- 238000007781 pre-processing Methods 0.000 claims description 3
- 230000008569 process Effects 0.000 description 6
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000003745 diagnosis Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000012937 correction Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000004445 quantitative analysis Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 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
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3275—Fault detection or status indication
-
- 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
- G01R19/175—Indicating the instants of passage of current or voltage through a given value, e.g. passage through zero
-
- 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
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3271—Testing of circuit interrupters, switches or circuit-breakers of high voltage or medium voltage devices
- G01R31/3272—Apparatus, systems or circuits therefor
Abstract
The application discloses a method for diagnosing the state time point of a medium-voltage switch and a related device, comprising the following steps of: collecting a plurality of groups of current waveform data of three phases of the on-off current nodes when the switch is switched on and off; calculating threshold values of all phases according to three-phase current waveform data, backward taking an array with the length of L from a first time point in any phase current waveform data, calculating the maximum value of the amplitude value, and analyzing the opening and closing states of the switch according to the magnitude relation between the threshold values of all phases and the maximum value of the amplitude value; when the switch is in a switching-off state, acquiring an alternative data set from back to front in an array with the length of L, and according to the data change rate of each data point in the alternative data set; selecting a data point corresponding to the maximum data change rate value in the first alternative data set, converting the data point into time according to the sampling start time and the sampling rate, and calculating the switching-off time; and calculating the closing time by the method. Therefore, the problem that the time point of the on-off state of the power distribution switch cannot be accurately calculated in the prior art is solved.
Description
Technical Field
The present disclosure relates to the field of power technologies, and in particular, to a method and a related device for diagnosing a time point of a medium voltage switch.
Background
Distribution medium voltage switch is the important equipment of electric wire netting, and this type of switch adopts mechanical structure mostly, and in practical application, the mechanical structure of switch often breaks down. Statistically, more than 70% of switch failures are caused by mechanical mechanisms, and the failure types mainly include: the mechanical characteristic test of the switch is an important guarantee for guaranteeing the safe and stable operation of the switch. In the process of testing the mechanical performance of the switch, the detection of the performance of the switch and the fault judgment are mainly completed by measuring key mechanical parameters such as opening and closing time, three-phase different-phase time, reclosing time, bouncing time and the like in the operation process of the switch. The opening/closing time parameter is an important index for judging the opening/closing performance of the switch. And the opening and closing time node of the current power distribution switch is mainly identified by judging the switch state, and cannot be subjected to quantitative analysis.
When the mechanical characteristic opening and closing time of the distribution medium-voltage switch is detected, the sensor needs to be connected to the auxiliary contact for detection when the switch state quantity is obtained, but the distance from the auxiliary switch to the front end of the mechanical characteristic detection is far, and wiring is difficult. Especially when the monitored object is a distribution network switch cabinet, the operation of adding signal wires on the auxiliary contacts is very complicated because the mechanical mechanism and the switch are designed into a whole, and no idle contact is often available because the number of the auxiliary contacts of the switch is limited. When the switching state quantity is difficult to obtain, the switching-on and switching-off time information cannot be accurately obtained by the traditional method. In addition, even if the time point of the switching state can be measured smoothly by the method, because the time characteristic curve of the power distribution switching state is not an ideal reversal pulse, the switching time of the auxiliary contact is used as the just-dividing and just-combining point, inherent errors can not be eliminated, and the just-dividing and just-combining point is calculated inaccurately. The time measured by the method is not accurate, and the accurate quantitative analysis of the opening and closing time of the switch is difficult to carry out.
Disclosure of Invention
The application provides a diagnosis method of a medium-voltage switch state time point and a related device, which are used for solving the technical problem that the time point of a power distribution switch on-off state cannot be accurately calculated in the prior art.
In view of the above, a first aspect of the present application provides a method for diagnosing a state time point of a medium voltage switch, the method comprising:
s1, when a switch is switched on and off, continuously collecting a plurality of groups of current waveform data of three phases of a switching-on/off current node at the same time, and calculating the length of each group of current waveform data;
s2, calculating threshold values of all phases according to three-phase current waveform data, taking an array with the length of L from a first time point backward in any phase current waveform data, calculating an amplitude maximum value SMAmp, and analyzing the opening and closing states of the switch according to the size relation between the threshold values of all phases and the SMAmp;
s3, when the switch is in a switching-off state, acquiring a first alternative data set from back to front of an array with the length of L, and according to the data change rate of each data point in the first alternative data set; selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to sampling start time and the sampling rate, and calculating to obtain switching-off time;
s4, when the switch is in a closing state, acquiring a second alternative data set from front to back of an array with the length of L, and according to the data change rate of each data point in the second alternative data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
Optionally, step S3 specifically includes:
s31, when the switch is in a switching-off state, finding a first point X larger than a threshold value from back to front in an array with the length of L;
s32, from the point X, taking data with the length of L X0.5 in the array with the length of L as the second candidate data set;
s33, calculating the data change rate of each data point i in the first alternative data set;
s34, selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time.
Optionally, step S4 specifically includes:
s41, when the switch is in a closing state, finding a first point Y larger than a threshold value from front to back in the array with the length of L;
s42, starting from the point Y, taking data with the length of L x 0.5 in the array with the length of L as the second alternative data set;
s43, calculating the data change rate of each data point i in the second candidate data set;
and S44, selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
Optionally, step S1 is followed by:
respectively forming three-phase current waveform data into data matrixes, wherein each line in the data matrixes of all phases is a group of data;
and respectively calculating the correlation between the same rows between every two of the three data matrixes to obtain the correlation between each group of data, executing the step S2 when the correlation deviation between each group of data in the three phases is not greater than a preset threshold value, and otherwise, returning to the step S1.
A second aspect of the present application provides a diagnostic system for a state time point of a medium voltage switch, the system comprising:
the acquisition unit is used for continuously acquiring a plurality of groups of current waveform data of three phases of the on-off current node and calculating the length of each group of current waveform data when the switch is switched on and off;
the analysis unit is used for calculating the threshold of each phase according to the three-phase current waveform data, taking an array with the length of L from a first time point backward in any phase current waveform data, calculating the maximum value SMAmp of the amplitude, and analyzing the opening and closing state of the switch according to the size relation between the threshold of each phase and the SMAmp;
the first calculation unit is used for acquiring a first alternative data set from back to front of an array with the length of L when the switch is in an opening state, and according to the data change rate of each data point in the first alternative data set; selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to sampling start time and the sampling rate, and calculating to obtain switching-off time;
the second calculation unit is used for acquiring a second alternative data set from front to back of an array with the length of L when the switch is in a closing state, and according to the data change rate of each data point in the second alternative data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
Optionally, the first computing unit is specifically configured to:
when the switch is in an opening state, finding a first point X which is larger than a threshold value from back to front in an array with the length of L;
starting from the point X, taking data with the length of L X0.5 in the array with the length of L as the second alternative data set;
calculating a data change rate of each data point i in the first alternative data set;
and selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time.
Optionally, the second computing unit is specifically configured to:
when the switch is in a closing state, finding a first point Y which is larger than a threshold value from front to back in the array with the length of L;
starting from the point Y, taking data with the length of L x 0.5 in the array with the length of L as the second alternative data set;
calculating a data change rate of each data point i in the second candidate data set;
and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
Optionally, the method further comprises: a pre-processing unit to:
respectively forming three-phase current waveform data into data matrixes, wherein each line in the data matrixes of all phases is a group of data;
and respectively calculating the correlation between the same rows of every two of the three data matrixes to obtain the correlation between each group of data, triggering the analysis unit when the correlation deviation between each group of data in the three phases is not greater than a preset threshold value, and otherwise triggering the acquisition unit.
A third aspect of the present application provides a diagnostic device for a medium voltage switch state time point, the device comprising a processor and a memory:
the memory is used for storing program codes and transmitting the program codes to the processor;
the processor is configured to perform the steps of the method for diagnosing a time point of a state of a medium voltage switch according to the first aspect, according to instructions in the program code.
A fourth aspect of the present application provides a computer-readable storage medium for storing program code for performing the method for diagnosing a point in time of a medium voltage switch state as described in the first aspect above.
According to the technical scheme, the method has the following advantages:
the application provides a method for diagnosing a state time point of a medium-voltage switch, which comprises the following steps: s1, when a switch is switched on and off, a plurality of groups of current waveform data of three phases of a switching-on current node and a switching-off current node are continuously collected at the same time, and the length of each group of current waveform data is calculated; s2, calculating threshold values of all phases according to three-phase current waveform data, taking an array with the length of L from a first time point backward in any phase current waveform data, calculating an amplitude maximum value SMAmp, and analyzing the opening and closing states of the switch according to the size relation between the threshold values of all phases and the SMAmp; s3, when the switch is in a switching-off state, acquiring a first alternative data set from back to front of an array with the length of L, and according to the data change rate of each data point in the first alternative data set; selecting a first data point corresponding to the maximum data change rate value in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time; s4, when the switch is in a closing state, acquiring a second alternative data set from front to back of an array with the length of L, and according to the data change rate of each data point in the second alternative data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
Compared with the prior art, the diagnosis method for the state time point of the medium-voltage switch can accurately calculate the time point of the on-off state of the power distribution switch when the switching value information cannot be effectively acquired.
Drawings
Fig. 1 is a schematic flowchart of an embodiment of a method for diagnosing a state time point of a medium voltage switch provided in an embodiment of the present application;
fig. 2 is a schematic structural diagram of an embodiment of a diagnostic system for a state time point of a medium voltage switch provided in an embodiment of the present application.
Detailed Description
In order to make those skilled in the art better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all 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 application.
Referring to fig. 1, a method for diagnosing a state time point of a medium voltage switch provided in an embodiment of the present application includes:
in the present embodiment, the CT with the storage function is installed at the switching current node of the power distribution switch, so that corresponding current waveform data can be acquired when the switch is switched on and off. Specifically, 50 sets of three-phase data are continuously acquired, the length L of each set of data is calculated according to the sampling rate SR and the switch operation frequency SysR (generally power frequency), the accuracy of subsequent calculation is influenced by the sampling rate, a higher sampling rate is generally set under the condition that the processing capacity of the MCU is not influenced, the MCU selects a single chip microcomputer after the factors such as cost performance and the like are considered, and the sampling rate is generally set to be 10 k. L is represented by the following formula:
three phases are simultaneously carried out during data acquisition, data acquisition corresponds to acquisition time one by one, actual measurement proves that the data of each group of three phases have correlation at the same time, and in order to ensure that the three-phase data correspond to the acquisition time, the correlation of B, C is judged by taking the phase A as a reference. And respectively forming the three-phase data into a matrix.
102, respectively calculating the correlation between the same rows of every two of the three data matrixes to obtain the correlation between each group of data, executing a step 103 when the correlation deviation between each group of data in the three phases is not greater than a preset threshold, and otherwise, returning to the step 101;
it should be noted that each action is a set of data. If the sampling times correspond, then there should be consistent correlation between the same rows of the three matrices. Therefore, ρ AB is first obtained as follows:
then, rho BC, rho CA. are obtained, then 50 groups of data are traversed, rho AB, rho BC and rho CA among each group of data are respectively obtained, and when deviation among three numerical values of each group is not more than 10%, three-phase sampling is considered to be simultaneous. If the sampling rate exceeds 10%, the sampling returns to the step 101 again.
103, calculating threshold values of all phases according to the three-phase current waveform data, taking an array with the length of L from a first time point backward in any phase current waveform data, calculating an amplitude maximum value SMAmp, and analyzing the opening and closing states of the switch according to the size relation between the threshold values of all phases and the SMAmp;
note that, threshold calculation is performed based on the three-phase current waveform data, and the description will be given by taking the current waveform of the a phase as an example, specifically:
taking A-phase current waveform data DA, taking absolute values of all data in DA to obtain data AbsDA, calculating an average value PA of the data AbsDA, then calculating a median M of the data AbsDA, and calculating a threshold:
where k is a correction coefficient, the initial value of which is 0.5, and correction will be performed according to subsequent calculation and comparison.
In any phase current waveform Data, backward taking Data with the length of L from a first time point, and calculating the maximum value SMAmp of the amplitude;
when the switch acts as a separating brake, SMAmp and Tz satisfy the following formula:
when the switch is switched on, SMAmp and Tz satisfy the following formula:
therefore, whether the switch is in an opening state or a closing state at present is judged.
104, when the switch is in a switching-off state, acquiring a first alternative data set from back to front of an array with the length of L, and according to the data change rate of each data point in the first alternative data set; selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time;
it should be noted that when
Then, the time point of opening each phase can be calculated by the following method:
1) Finding a first point X larger than a threshold value Tz from back to front in the array with the length L;
2) Starting from the point X, taking data with the length L X0.5 in the array as a candidate data set SLData;
3) For each data point i, i in the SLData, the range is [ 0-L × 0.5-1], the data change rate ROC [ i ] is calculated as follows:
4) And taking the maximum value of ROC [ i ] in the SLData, and converting i into time according to the sampling start time and the sampling rate to obtain the switching-off time. For example, the sampling rate is 10k, the set of initial sampling time points is 12 pm, the switch operating frequency is 50hz, roc 2 is maximum, and then the opening time is 50 × 20/10k =0.1s, i.e. 0.1s after 12 pm.
5) Compared with three-phase brake-off time, the deviation is not more than 5%, and important attention of equipment is paid to the deviation exceeding 5%.
105, when the switch is in a closing state, acquiring a second alternative data set from front to back of an array with the length of L, and according to the data change rate of each data point in the second alternative data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
It should be noted that when
Then, the closing time point of each phase can be calculated by the following method:
1) Finding a first point Y larger than a threshold value Tz from the array with the length L from front to back;
2) Starting from the point Y, taking data with the length L x 0.5 in the array as an alternative data set SLData;
3) For each data point i, i in the SLData, ranging from [ 0-L0.5-1 ], the data rate of change ROC [ i ] is calculated as follows:
4) And taking the maximum value of ROC [ i ] in the SLData, and converting i into time according to the sampling start time and the sampling rate to obtain the switching-off time. For example, the sampling rate is 10k, the set of initial sampling time points is 12 pm, the switch operating frequency is 50hz, roc 2 is maximum, and then the opening time is 50 × 20/10k =0.1s, i.e. 0.1s after 12 pm.
5) Compared with three-phase closing time, the deviation is not more than 5%, and important attention of equipment is paid to when the deviation exceeds 5%.
The above is a method for diagnosing a time point of a medium voltage switch state provided in the embodiment of the present application, and the following is a system for diagnosing a time point of a medium voltage switch state provided in the embodiment of the present application.
Referring to fig. 2, in an embodiment of the present application, a diagnostic system for a state time point of a medium voltage switch includes:
the acquisition unit 201 is used for continuously acquiring a plurality of groups of current waveform data of three phases of the on-off current node and calculating the length of each group of current waveform data when the switch is switched on and off;
the preprocessing unit 202 is used for respectively forming three-phase current waveform data into data matrixes, wherein each row in the data matrixes of all phases is a group of data; and respectively calculating the correlation between the same rows between every two matrixes in the three data matrixes to obtain the correlation between each group of data, and triggering the analysis unit when the correlation deviation between each group of data in the three phases is not greater than a preset threshold value, otherwise triggering the acquisition unit.
The analysis unit 203 is used for calculating the threshold of each phase according to the three-phase current waveform data, backwards taking an array with the length of L from the first time point in any phase current waveform data, calculating the maximum value SMAmp of the amplitude, and analyzing the opening and closing state of the switch according to the size relation between the threshold of each phase and the SMAmp;
the first calculating unit 204 is configured to, when the switch is in an open state, obtain a first candidate data set from back to front in an array with a length of L, and obtain a data change rate of each data point in the first candidate data set; selecting a first data point corresponding to the maximum data change rate value in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time;
a second calculating unit 205, configured to, when the switch is in a closed state, obtain a second candidate data set from front to back in the array with the length of L, and according to a data change rate of each data point in the second candidate data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
Further, the embodiment of the present application also provides a diagnostic device for a medium voltage switch state time point, where the device includes a processor and a memory:
the memory is used for storing program codes and transmitting the program codes to the processor;
the processor is used for executing the diagnosis method of the state time point of the medium voltage switch according to the instruction in the program code.
Further, an embodiment of the present application further provides a computer-readable storage medium, where the computer-readable storage medium is configured to store program codes, and the program codes are configured to execute the method for diagnosing a state time point of a medium voltage switch according to the method embodiment.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
The terms "first," "second," "third," "fourth," and the like in the description of the application and the above-described figures, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
It should be understood that in the present application, "at least one" means one or more, "a plurality" means two or more. "and/or" for describing an association relationship of associated objects, indicating that there may be three relationships, e.g., "a and/or B" may indicate: only A, only B and both A and B are present, wherein A and B may be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.
In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit may be implemented in the form of hardware, or may also be implemented in the form of a software functional unit.
The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application, which are essential or part of the technical solutions contributing to the prior art, or all or part of the technical solutions, may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: a U disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.
The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.
Claims (10)
1. A method for diagnosing a time point of a state of a medium voltage switch, comprising:
s1, when a switch is switched on and off, a plurality of groups of current waveform data of three phases of a switching-on current node and a switching-off current node are continuously collected at the same time, and the length of each group of current waveform data is calculated;
s2, calculating threshold values of all phases according to three-phase current waveform data, taking an array with the length of L from a first time point backward in any phase current waveform data, calculating an amplitude maximum value SMAmp, and analyzing the opening and closing states of the switch according to the size relation between the threshold values of all phases and the SMAmp;
s3, when the switch is in a switching-off state, acquiring a first alternative data set from back to front of an array with the length of L, and according to the data change rate of each data point in the first alternative data set; selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to sampling start time and the sampling rate, and calculating to obtain switching-off time;
s4, when the switch is in a closing state, acquiring a second alternative data set from front to back of an array with the length of L, and according to the data change rate of each data point in the second alternative data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
2. The method for diagnosing a state time point of a medium voltage switch according to claim 1, wherein step S3 specifically comprises:
s31, when the switch is in a switching-off state, finding a first point X larger than a threshold value from back to front in an array with the length of L;
s32, starting from the point X, taking data with the length of L X0.5 in the array with the length of L as the second alternative data set;
s33, calculating the data change rate of each data point i in the first candidate data set;
s34, selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time.
3. The method for diagnosing a state time point of a medium voltage switch according to claim 1, wherein step S4 specifically comprises:
s41, when the switch is in a closing state, finding a first point Y larger than a threshold value from front to back in the array with the length of L;
s42, starting from the point Y, taking data with the length of L x 0.5 in the array with the length of L as the second alternative data set;
s43, calculating the data change rate of each data point i in the second candidate data set;
and S44, selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
4. The method for diagnosing a state time point of a medium voltage switch according to claim 1, wherein step S1 is followed by further comprising:
respectively forming three-phase current waveform data into data matrixes, wherein each line in the data matrixes of all phases is a group of data;
and respectively calculating the correlation between the same rows of every two of the three data matrixes to obtain the correlation between each group of data, executing the step S2 when the correlation deviation between each group of data in the three phases is not greater than a preset threshold value, and otherwise, returning to the step S1.
5. A diagnostic system for a medium voltage switch state time point, comprising:
the acquisition unit is used for continuously acquiring a plurality of groups of current waveform data of three phases of the switching-on and switching-off current nodes simultaneously when the switch is switched on and off, and calculating the length of each group of current waveform data;
the analysis unit is used for calculating the threshold of each phase according to the three-phase current waveform data, taking an array with the length of L from a first time point backward in any phase current waveform data, calculating the maximum value SMAmp of the amplitude, and analyzing the opening and closing state of the switch according to the size relation between the threshold of each phase and the SMAmp;
the first calculation unit is used for acquiring a first alternative data set from back to front of an array with the length of L when the switch is in an opening state, and according to the data change rate of each data point in the first alternative data set; selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to sampling start time and the sampling rate, and calculating to obtain switching-off time;
the second calculation unit is used for acquiring a second alternative data set from front to back of an array with the length of L when the switch is in a closing state, and according to the data change rate of each data point in the second alternative data set; and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
6. The system according to claim 5, wherein the first computing unit is specifically configured to:
when the switch is in a switching-off state, finding a first point X which is larger than a threshold value from back to front in an array with the length of L;
starting from the point X, taking data with the length of L X0.5 in the array with the length of L as the second alternative data set;
calculating a data change rate of each data point i in the first alternative data set;
and selecting a first data point corresponding to the value with the maximum data change rate in the first alternative data set, converting the first data point into time according to the sampling start time and the sampling rate, and calculating to obtain the switching-off time.
7. The system according to claim 5, wherein the second computing unit is specifically configured to:
when the switch is in a closing state, finding a first point Y which is larger than a threshold value from front to back in the array with the length of L;
starting from the point Y, taking data with the length of L x 0.5 in the array with the length of L as the second alternative data set;
calculating a data change rate of each data point i in the second candidate data set;
and selecting a second data point corresponding to the value with the maximum data change rate in the second alternative data set, converting the second data point into time according to the sampling start time and the sampling rate, and calculating to obtain the closing time.
8. The system for diagnosing a state time point of a medium voltage switch according to claim 5, further comprising: a pre-processing unit to:
respectively forming three-phase current waveform data into data matrixes, wherein each line in the data matrixes of all phases is a group of data;
and respectively calculating the correlation between the same rows between every two of the three data matrixes to obtain the correlation between each group of data, triggering the analysis unit when the correlation deviation between each group of data in the three phases is not greater than a preset threshold value, and triggering the acquisition unit otherwise.
9. A diagnostic device for a medium voltage switch state time point, characterized in that the device comprises a processor and a memory:
the memory is used for storing program codes and transmitting the program codes to the processor;
the processor is configured to execute the method for diagnosing a time point of a state of a medium voltage switch according to any one of claims 1 to 4, according to instructions in the program code.
10. A computer-readable storage medium, characterized in that the computer-readable storage medium is used to store program code for performing the method for diagnosing a medium voltage switch state point in time of any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211269469.6A CN115327371A (en) | 2022-10-17 | 2022-10-17 | Method for diagnosing state time point of medium-voltage switch and related device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211269469.6A CN115327371A (en) | 2022-10-17 | 2022-10-17 | Method for diagnosing state time point of medium-voltage switch and related device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115327371A true CN115327371A (en) | 2022-11-11 |
Family
ID=83915307
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211269469.6A Pending CN115327371A (en) | 2022-10-17 | 2022-10-17 | Method for diagnosing state time point of medium-voltage switch and related device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115327371A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108519514A (en) * | 2018-04-24 | 2018-09-11 | 宁波三星医疗电气股份有限公司 | Taiwan area phase recognition methods based on Pearson correlation coefficient algorithm |
| CN109298362A (en) * | 2018-09-10 | 2019-02-01 | 国网江苏省电力有限公司电力科学研究院 | A kind of distribution line failure indicator three-phase synchronous method for testing precision, device and system |
| CN110686888A (en) * | 2019-11-07 | 2020-01-14 | 广东电网有限责任公司 | Method for judging just opening and just closing point of circuit breaker |
| CN113466548A (en) * | 2021-08-06 | 2021-10-01 | 国网四川省电力公司营销服务中心 | Intelligent electric meter region identification method based on phasor measurement technology |
| CN115078938A (en) * | 2022-08-22 | 2022-09-20 | 广东电网有限责任公司佛山供电局 | Method and device for identifying insulating property of lightning arrester |
-
2022
- 2022-10-17 CN CN202211269469.6A patent/CN115327371A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108519514A (en) * | 2018-04-24 | 2018-09-11 | 宁波三星医疗电气股份有限公司 | Taiwan area phase recognition methods based on Pearson correlation coefficient algorithm |
| CN109298362A (en) * | 2018-09-10 | 2019-02-01 | 国网江苏省电力有限公司电力科学研究院 | A kind of distribution line failure indicator three-phase synchronous method for testing precision, device and system |
| CN110686888A (en) * | 2019-11-07 | 2020-01-14 | 广东电网有限责任公司 | Method for judging just opening and just closing point of circuit breaker |
| CN113466548A (en) * | 2021-08-06 | 2021-10-01 | 国网四川省电力公司营销服务中心 | Intelligent electric meter region identification method based on phasor measurement technology |
| CN115078938A (en) * | 2022-08-22 | 2022-09-20 | 广东电网有限责任公司佛山供电局 | Method and device for identifying insulating property of lightning arrester |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110596533B (en) | Power distribution network single-phase earth fault section positioning method and system | |
| US9864008B2 (en) | Electric power system circuit breaker trip diagnostic | |
| EP2082246A2 (en) | Cable fault detection | |
| CN109307798B (en) | Power signal filtering method for switch event detection | |
| CN112986754B (en) | Small current grounding system fault identification method and device based on data driving | |
| JP2012090398A (en) | Method for monitoring short-circuit capacity of electric power system and system of the same | |
| CN108009063A (en) | The method of a kind of electronic equipment fault threshold detection | |
| CN111551352B (en) | Method and system for detecting state of breaker of GIS (geographic information System) equipment | |
| CN115327371A (en) | Method for diagnosing state time point of medium-voltage switch and related device | |
| CN111880020A (en) | Fault recording data generation method and device for power distribution and utilization system of power consumer | |
| JP4470221B2 (en) | Ground fault detection method and apparatus | |
| JP2019039845A (en) | Partial discharge diagnosis device and partial discharge diagnosis method | |
| CN111751663A (en) | Method and system for drawing fault overall process time sequence based on power grid fault recording graph | |
| CN111666870A (en) | Power signal reconstruction method and system by utilizing quadratic constraint | |
| CN106646106A (en) | Power grid fault detection method based on change point detection technology | |
| KR20120136952A (en) | System and method for monitoring ground fault of high resistance | |
| CN113945801B (en) | Power distribution network fault positioning method, device, equipment and storage medium | |
| CN115600879A (en) | Circuit breaker abnormity early warning method, system and related device | |
| CN109375144B (en) | Current loss fault monitoring method and device based on three-phase four-wire meter equipment | |
| CN111025187B (en) | Ground fault early warning method, device and equipment and storage medium | |
| Xing et al. | Open-circuit fault detection and location in MMCs with multivariate gaussian distribution | |
| CN113655344B (en) | Power distribution network fault identification method, device, terminal and medium | |
| CN115343579B (en) | Power grid fault analysis method and device and electronic equipment | |
| CN116454908B (en) | Capacitor bank switching frequency counting method and device | |
| CN114142605B (en) | Pilot protection method, device and 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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20221111 |