Disclosure of Invention
The invention provides a characteristic analysis method, a characteristic analysis system, terminal equipment and a storage medium for a current transformer, which are used for solving the technical gap of effect characteristic analysis of the current transformer under the influence of extreme geomagnetic induction in the prior art.
In order to solve the technical problems, the embodiment of the invention provides a current transformer characteristic analysis method which is suitable for a current transformer characteristic analysis system, wherein the current transformer characteristic analysis system comprises an adjustable current source, an extremely-magnetic induction current analog injection source, a current transformer to be analyzed, an adjustable load and a data acquisition and analysis device, wherein the adjustable current source is connected with the primary side of the current transformer, the extremely-magnetic induction current analog injection source is connected with the primary side of the current transformer and is connected with the adjustable current source in parallel, the adjustable load is connected with the secondary side of the current transformer, and the extremely-magnetic induction current analog injection source is formed by connecting a capacitor bank and a resistance cabinet in series;
the characteristic analysis method of the current transformer comprises the following steps:
acquiring a specified working state and a specified load state of the current transformer, and acquiring a specified current level of extremely magnetically induced current to be simulated, wherein the working state comprises normal, near-saturated and saturated states;
According to the operation current setting interval, adjusting the operation current output by the adjustable current source;
According to the specified load state, a corresponding load setting interval is determined, and the load value of the adjustable load is adjusted according to the load setting interval;
Determining a target charging voltage corresponding to the current level according to the specified current level and the resistance value of the resistor cabinet; after the capacitor bank is controlled to be charged to the target charging voltage, the capacitor bank is controlled to output an extreme geomagnetic induction analog current to the current transformer;
Collecting primary side current data and secondary side current data of the current transformer through the data collecting and analyzing device; and determining excitation characteristics and transfer characteristics of the current transformer according to the primary side current data and the secondary side current data.
Preferably, the determining the excitation characteristic and the transformation characteristic of the current transformer according to the primary side current data and the secondary side current data includes:
Converting the primary side current data to a secondary side to obtain converted current data;
Calculating the difference between the converted current data and the secondary side current data to obtain the excitation characteristic of the current transformer;
Performing Fourier transform on the converted current data to obtain a first fundamental wave amplitude and a first phase of the converted current data; performing Fourier transform on the secondary side current data to obtain a second fundamental wave amplitude value and a second phase of the secondary side current data;
And calculating the amplitude errors of the first fundamental wave amplitude and the second fundamental wave amplitude and the phase errors of the first phase and the second phase, and obtaining the transfer characteristic of the current transformer according to the amplitude errors and the phase errors.
Preferably, the collecting primary side current data and secondary side current data of the current transformer includes:
Collecting an extreme geomagnetic induction analog current value output by the extreme geomagnetic induction current analog injection source;
And when the extreme geomagnetic induction analog current value is greater than or equal to a preset current amplitude threshold value, starting to acquire primary side current data and secondary side current data of the current transformer.
The data acquisition and analysis device comprises a current clamp and a data analysis module, wherein the current clamp is used for acquiring current data.
On the basis of the embodiment, the other embodiment of the invention provides a characteristic analysis system of a current transformer, which comprises an adjustable current source, an extremely geomagnetic induction current simulation injection source, a current transformer to be analyzed, an adjustable load and a data acquisition and analysis device;
the adjustable current source is connected with the primary side of the current transformer, the extremely-magnetically-induced current analog injection source is connected with the primary side of the current transformer, the adjustable current source is connected with the extremely-magnetically-induced current analog injection source in parallel, and the adjustable load is connected with the secondary side of the current transformer;
The adjustable current source is used for outputting an operating current with an adjustable effective value;
The extremely-magnetic induction current simulation injection source comprises a resistor cabinet and a capacitor bank, wherein the resistor cabinet and the capacitor bank are connected in series;
the adjustable load is used for providing an adjustable load for the current transformer;
The data acquisition and analysis device is used for acquiring primary side current data and secondary side current data of the current transformer, and determining excitation characteristics and transmission characteristics of the current transformer according to the primary side current data and the secondary side current data.
Preferably, the determining the excitation characteristic and the transformation characteristic of the current transformer according to the primary side current data and the secondary side current data includes:
Converting the primary side current data to a secondary side to obtain converted current data;
Calculating the difference between the converted current data and the secondary side current data to obtain the excitation characteristic of the current transformer;
Performing Fourier transform on the converted current data to obtain a first fundamental wave amplitude and a first phase of the converted current data; performing Fourier transform on the secondary side current data to obtain a second fundamental wave amplitude value and a second phase of the secondary side current data;
And calculating the amplitude errors of the first fundamental wave amplitude and the second fundamental wave amplitude and the phase errors of the first phase and the second phase, and obtaining the transfer characteristic of the current transformer according to the amplitude errors and the phase errors.
Preferably, the collecting primary side current data and secondary side current data of the current transformer includes:
Collecting an extreme geomagnetic induction analog current value output by the extreme geomagnetic induction current analog injection source;
And when the extreme geomagnetic induction analog current value is greater than or equal to a preset current amplitude threshold value, starting to acquire primary side current data and secondary side current data of the current transformer.
The data acquisition and analysis device comprises a current clamp and a data analysis module, wherein the current clamp is used for acquiring current data.
On the basis of the above embodiment, a further embodiment of the present invention provides a terminal device, where the terminal device includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, where the processor executes the computer program to implement the method for analyzing characteristics of a current transformer according to the embodiment of the present invention.
On the basis of the above embodiment, a further embodiment of the present invention provides a storage medium, where the storage medium includes a stored computer program, where the computer program controls a device where the storage medium is located to execute the method for analyzing characteristics of a current transformer according to the above embodiment of the present invention when running.
Compared with the prior art, the embodiment of the invention has the following beneficial effects:
The invention can simulate the current transformer to suffer from different levels of extreme magnetic induction current invasion in different working states and load states by designating different working states and load states of the current transformer and designating different voltage levels of the extreme magnetic induction current, collect the primary side current waveform and the secondary side current of the current transformer and analyze the excitation characteristic and the transmission characteristic of the current transformer under the action of the extreme geomagnetic induction current. The invention can provide basis for analyzing the characteristics of the current transformer taking into account the extremely-induced current, fills the technical gap of the prior art aiming at the effect characteristic analysis of the current transformer under the influence of the extremely-induced geomagnetic induction, and has important significance for improving the operation reliability of the current transformer.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs, the terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting of the application, and the terms "comprising" and any variations thereof in the description of the application and the claims and the above description of the drawings are intended to cover non-exclusive inclusions.
In the description of embodiments of the present application, the technical terms "first," "second," and the like are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.
In describing embodiments of the present application, unless explicitly stated or limited otherwise, the term "coupled" shall be construed broadly, and may be, for example, fixedly coupled, detachably coupled, or integrally formed, mechanically coupled, electrically coupled, directly coupled, indirectly coupled via an intermediate medium, or in communication between two elements or in an interaction relationship between two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to specific circumstances.
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
Referring to fig. 1, a flow chart of a current transformer characteristic analysis method provided by an embodiment of the invention is suitable for a current transformer characteristic analysis system, wherein the current transformer characteristic analysis system comprises an adjustable current source, an extremely-magnetic induction current analog injection source, a current transformer to be analyzed, an adjustable load and a data acquisition and analysis device, the adjustable current source is connected with a primary side of the current transformer, the extremely-magnetic induction current analog injection source is connected with the primary side of the current transformer and is connected with the adjustable current source in parallel, the adjustable load is connected with a secondary side of the current transformer, and the extremely-magnetic induction current analog injection source is formed by connecting a capacitor bank and a resistor cabinet in series.
The characteristic analysis method of the current transformer comprises the following steps:
S1, acquiring a specified working state and a specified load state of the current transformer, and acquiring a specified current level of the extremely magnetically induced current to be simulated, wherein the working state comprises normal, near-saturated and saturated states, and the load state comprises light load, rated load and overload.
The invention adopts the 10kV voltage class true current transformer to simulate the real situation of power equipment in operation.
In one embodiment, the current transformer is an LZZBJ9-10 type current transformer.
S2, determining a corresponding operation current setting interval according to the appointed working state, and adjusting the operation current output by the adjustable current source according to the operation current setting interval.
The adjustable current source is an alternating current source and provides power for the operation of the current transformer, so that the effective value of the output current can be adjusted, and the working state of the current transformer can be adjusted.
S3, determining a corresponding load setting interval according to the appointed load state, and adjusting the load value of the adjustable load according to the load setting interval.
The load is composed of resistors with different resistance values and inductors with different inductance values, and is used for providing a load for the current transformer, so that the working state of the current transformer is adjustable, and the load power factor is adjustable.
In step S3, setting the load condition of the current transformer, if the current transformer is in an overload state, the load impedance is required to be larger than the rated load impedance, if the current transformer is in a rated state, the load impedance is required to be the rated load impedance, if the current transformer is in a light load state, the load impedance is required to be smaller than 25% of the rated load impedance, and setting the load resistance value and the inductance value according to the load impedance value.
And S4, determining a target charging voltage corresponding to the current grade according to the designated current grade and the resistance value of the resistor cabinet, and controlling the capacitor bank to output an extreme geomagnetic induction analog current to the current transformer after controlling the capacitor bank to charge to the target charging voltage.
The extremely magnetically induced current simulation injection source is used for simulating extremely magnetically induced currents of different grades. The extremely-low-voltage magnetic induction current injection level is adjusted by adjusting the charging voltage.
In step S4, the level of extremely magnetically induced current is set, and the influence of the extremely magnetically induced current on the current transformer is used as a standard for grading, when the current amplitude is less than 50A, the level will cause slight magnetic bias saturation of the current transformer, when the current amplitude is greater than 50A and less than 300A, the level will cause relay protection rejection of the current transformer, and when the current amplitude is greater than 300A, the level will cause deep saturation of the current transformer, and the operation safety of the current transformer is threatened.
S5, collecting primary side current data and secondary side current data of the current transformer through the data collecting and analyzing device, and determining excitation characteristics and transmission characteristics of the current transformer according to the primary side current data and the secondary side current data.
The data acquisition and analysis device acquires the transfer characteristics of the current transformer from the rapidly-changed current waveform data, can evaluate the working state of the current transformer taking the action of extremely geomagnetic induced current into account, and has important significance for improving the operation reliability of the current transformer.
In a preferred embodiment, the determining the excitation characteristic and the transformation characteristic of the current transformer according to the primary side current data and the secondary side current data includes:
Converting the primary side current data to a secondary side to obtain converted current data;
Calculating the difference between the converted current data and the secondary side current data to obtain the excitation characteristic of the current transformer;
Performing Fourier transform on the converted current data to obtain a first fundamental wave amplitude and a first phase of the converted current data; performing Fourier transform on the secondary side current data to obtain a second fundamental wave amplitude value and a second phase of the secondary side current data;
And calculating the amplitude errors of the first fundamental wave amplitude and the second fundamental wave amplitude and the phase errors of the first phase and the second phase, and obtaining the transfer characteristic of the current transformer according to the amplitude errors and the phase errors.
In a preferred embodiment, the collecting primary side current data and secondary side current data of the current transformer includes:
Collecting an extreme geomagnetic induction analog current value output by the extreme geomagnetic induction current analog injection source;
And when the extreme geomagnetic induction analog current value is greater than or equal to a preset current amplitude threshold value, starting to acquire primary side current data and secondary side current data of the current transformer.
The current amplitude threshold is 50% of the specified current level.
In this embodiment, a triggering mode of the data acquisition operation is set based on a specified current level, and when the extremely magnetically-induced current measurement channel detects that the current value is greater than or equal to 50% of the specified current level, the data acquisition operation is triggered to ensure that the current data acquisition is complete, and if the current data acquisition is triggered too early or too late, the waveform recording is incomplete.
In a preferred embodiment, the data acquisition and analysis device comprises a current clamp and a data analysis module, wherein the current clamp is used for acquiring current data.
The current clamp is used for collecting primary side current data and secondary side current data of the current transformer and also collecting an extreme geomagnetic induction analog current value output by an extreme induction current analog injection source. The invention considers the problem that the traditional current measuring equipment can generate magnetic bias phenomenon under the action of extreme geomagnetic induced current so as to not accurately measure the current, adopts the current clamp to measure the current, and can accurately obtain the primary side secondary side current of the current transformer.
In one embodiment, the data acquisition and analysis device further comprises an oscilloscope module used for displaying primary side current data and secondary side current data of the current transformer and having a data storage function. The oscilloscope module is an eight-channel oscilloscope.
In an embodiment, the data acquisition and analysis device is further configured to determine an operation state of the current transformer according to the amplitude error and the phase error. Taking the LZZBJ9-10 type current transformer selected in the invention as an example, when the absolute value of the amplitude error is not more than 5% and the absolute value of the phase error is not more than 180', the current transformer works in a linear region, when the absolute value of the amplitude error is more than 5% and less than 15% and the absolute value of the phase error is more than 180' and less than 360', the current transformer works in a critical saturation region, and when the absolute value of the amplitude error is more than 15% and the absolute value of the phase error is more than 360', the current transformer works in a deep saturation region. And comparing the characteristic parameters with error thresholds of the current transformer specified by the standard to judge whether the current transformer can measure current in the error thresholds under the action of the extremely geomagnetic induced current.
The invention can simulate the effect characteristics of the current transformer when suffering from different grades of extreme magnetic induction current invasion by designating different current transformer working states and load states and designating different voltage grades of the extreme magnetic induction current, collect the extreme magnetic induction current waveform, the primary side current waveform and the secondary side current waveform of the current transformer, and obtain the characteristic change of the current transformer under the action of the extreme geomagnetic induction current, thereby evaluating the running condition of the current transformer under the action of the extreme geomagnetic induction current, providing basis for the characteristic analysis of the current transformer for accounting for the extreme magnetic induction current, and having important significance for improving the running reliability of the current transformer.
Example two
Referring to fig. 2, a schematic structural diagram of a characteristic analysis system for a current transformer 3 according to an embodiment of the present invention includes an adjustable current source 1, an extremely magnetically induced current analog injection source 2, a current transformer 3 to be analyzed, an adjustable load 4, and a data acquisition and analysis device;
The adjustable current source 1 is connected with the primary side of the current transformer 3, the extremely-magnetically-induced current analog injection source 2 is connected with the primary side of the current transformer 3, the adjustable current source 1 is connected with the extremely-magnetically-induced current analog injection source 2 in parallel, and the adjustable load 4 is connected with the secondary side of the current transformer 3;
the adjustable current source 1 is used for outputting an operating current with an adjustable effective value;
the extremely-magnetically-induced current simulation injection source 2 comprises a resistor cabinet and a capacitor bank, wherein the resistor cabinet and the capacitor bank are connected in series, and the capacitor bank is used for storing electric quantity and outputting extremely-magnetically-induced simulation current to the current transformer 3;
the adjustable load 4 is used for providing an adjustable load for the current transformer 3;
the data acquisition and analysis device is used for acquiring primary side current data and secondary side current data of the current transformer 3, and determining excitation characteristics and transmission characteristics of the current transformer 3 according to the primary side current data and the secondary side current data.
In a preferred embodiment, the determining the excitation characteristic and the transformation characteristic of the current transformer 3 according to the primary side current data and the secondary side current data includes:
Converting the primary side current data to a secondary side to obtain converted current data;
Calculating the difference between the converted current data and the secondary side current data to obtain the excitation characteristic of the current transformer 3;
Performing Fourier transform on the converted current data to obtain a first fundamental wave amplitude and a first phase of the converted current data; performing Fourier transform on the secondary side current data to obtain a second fundamental wave amplitude value and a second phase of the secondary side current data;
And calculating the amplitude errors of the first fundamental wave amplitude and the second fundamental wave amplitude and the phase errors of the first phase and the second phase, and obtaining the transfer characteristic of the current transformer 3 according to the amplitude errors and the phase errors.
In a preferred embodiment, the collecting primary side current data and secondary side current data of the current transformer 3 includes:
Collecting an extreme geomagnetic induction analog current value output by the extreme geomagnetic induction current analog injection source 2;
And when the extreme geomagnetic induction analog current value is larger than or equal to a preset current amplitude threshold value, starting to collect primary side current data and secondary side current data of the current transformer 3.
In a preferred embodiment, the data acquisition and analysis device comprises a current clamp and a data analysis module, wherein the current clamp is used for acquiring current data.
Example III
Accordingly, an embodiment of the present invention provides a terminal device, where the terminal device includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, where the processor implements the method for analyzing characteristics of a current transformer according to the embodiment of the present invention when executing the computer program.
Example IV
Accordingly, an embodiment of the present invention provides a storage medium, where the storage medium includes a stored computer program, where when the computer program runs, a device where the storage medium is controlled to execute the method for analyzing characteristics of a current transformer according to the embodiment of the present invention.
It should be noted that the system embodiments described above are merely illustrative, and that the units described as separate units may or may not be physically separate, and that units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. In addition, in the system embodiment of the present invention, the connection relationship between the modules represents that there is a communication connection between them, and may be specifically implemented as one or more communication buses or signal lines. Those of ordinary skill in the art will understand and implement the present invention without undue burden.
It will be clear to those skilled in the art that, for convenience and brevity, specific working procedures of the system described above may refer to corresponding procedures in the foregoing method embodiments, and are not described herein again.
The terminal equipment can be computing equipment such as a desktop computer, a notebook computer, a palm computer, a cloud server and the like. The terminal device may include, but is not limited to, a processor, a memory.
The Processor may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (DIGITAL SIGNAL Processor, DSP), application SPECIFIC INTEGRATED Circuit (ASIC), off-the-shelf Programmable gate array (Field-Programmable GATE ARRAY, FPGA) or other Programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like that is a control center of the device, connecting the various parts of the overall device using various interfaces and lines.
The memory may be used to store the computer program, and the processor may implement various functions of the device by running or executing the computer program stored in the memory, and invoking data stored in the memory. The memory may mainly include a storage program area which may store an operating system, an application program required for at least one function, etc., and a storage data area which may store data created according to the use of the mobile phone, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as a hard disk, memory, plug-in hard disk, smart memory card (SMART MEDIA CARD, SMC), secure Digital (SD) card, flash memory card (FLASH CARD), at least one disk storage device, flash memory device, or other volatile solid-state storage device.
The storage medium is a storage medium, and the computer program is stored in the storage medium, where the computer program, when executed by a processor, can implement the steps of the above-described method embodiments. Wherein the computer program comprises computer program code which may be in source code form, object code form, executable file or some intermediate form etc. The computer readable medium may include any entity or system capable of carrying the computer program code, a recording medium, a U disk, a removable hard disk, a magnetic disk, an optical disk, a computer Memory, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), an electrical carrier signal, a telecommunications signal, a software distribution medium, and so forth. It should be noted that the computer readable medium contains content that can be appropriately scaled according to the requirements of jurisdictions in which such content is subject to legislation and patent practice, such as in certain jurisdictions in which such content is subject to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.
While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that changes and modifications may be made without departing from the principles of the invention, such changes and modifications are also intended to be within the scope of the invention.