CN110333423B - Transformer current conversion method and device, computer equipment and storage medium - Google Patents
Transformer current conversion method and device, computer equipment and storage medium Download PDFInfo
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- CN110333423B CN110333423B CN201910532803.4A CN201910532803A CN110333423B CN 110333423 B CN110333423 B CN 110333423B CN 201910532803 A CN201910532803 A CN 201910532803A CN 110333423 B CN110333423 B CN 110333423B
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- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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- G01R31/62—Testing of transformers
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Abstract
The application relates to a transformer current conversion method, a transformer current conversion device, computer equipment and a storage medium. The method comprises the following steps: acquiring an electric energy signal of a primary side of a transformer; acquiring an electric energy signal of the secondary side of the transformer; calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer; calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer; and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side. The electric energy signals of the primary side and the secondary side of the transformer are acquired respectively, and the fundamental wave electric energy signals of the primary side and the fundamental wave electric energy signals of the secondary side are obtained through calculation according to the acquired electric energy signals, so that the influence of harmonic waves is eliminated, the transformation ratio of the transformer is calculated more accurately, and whether the transformer has faults or not is effectively judged.
Description
Technical Field
The present application relates to the field of power grid technologies, and in particular, to a transformer current conversion method, apparatus, computer device, and storage medium.
Background
In the high-voltage power supply and high-voltage metering occasions, the method for testing the fault or accuracy of the metering system under the conditions of power transmission and no power outage currently comprises the following two methods:
(1) high-voltage transformation ratio tester:
this method is a direct test. The transformation ratio can be directly calculated by testing the high-voltage current through a high-voltage current clamp and testing the secondary current through a 5A current clamp. This method has the disadvantages: overhead lines can only be tested once, or in situations where there is sufficient space. The high-voltage operating rod is adopted, high voltage is contacted, the site is dangerous, a plurality of persons are needed to cooperate to complete the test, and the large labor cost is consumed.
(2) The wireless inspection system comprises:
this method is an indirect test. The voltage and current of the secondary side of the transformer are tested and the electric energy is calculated by installing the instrument on the secondary side of the transformer. At the high-voltage metering position, the electric energy pulse of the metering electric energy meter is sent to an instrument in a wired or wireless mode, and the electric energy errors of the primary side and the secondary side of the transformer are compared to judge whether the high-voltage metering error is out of an allowable range. If the error exceeds the allowable range, the reasons may be errors of the electric energy meter, errors of the current transformer, errors of the voltage transformer or errors of the secondary wiring. In this way, the cause of the error cannot be directly determined, and the type of the failure cannot be determined.
Disclosure of Invention
In view of the above, it is necessary to provide a transformer current conversion method, apparatus, computer device and storage medium for solving the above technical problems.
A transformer current reduction method, the method comprising:
acquiring an electric energy signal of a primary side of a transformer;
acquiring an electric energy signal of the secondary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer;
and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
In one embodiment, the step of calculating the fundamental wave power signal of the primary side according to the power signal of the primary side of the transformer includes:
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the electric energy signal on the primary side of the transformer based on a fast Fourier transform algorithm.
In one embodiment, the step of calculating a fundamental electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer based on the fast fourier transform algorithm includes:
amplifying the electric energy signal at the primary side of the transformer into a first square wave signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the step of amplifying the power signal of the primary side of the transformer into the first square wave signal further includes:
performing digital-to-analog conversion and sampling on the first square wave signal by integral multiple of the power frequency of the transformer to obtain a first conversion signal;
the step of calculating to obtain the fundamental wave electric energy signal on the primary side according to the first square wave signal based on the fast fourier transform algorithm is as follows:
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first conversion signal based on a fast Fourier transform algorithm.
In one embodiment, the step of calculating a fundamental wave power signal of the secondary side according to the power signal of the secondary side of the transformer includes:
and calculating to obtain a fundamental wave electric energy signal of the secondary side of the transformer according to the electric energy signal of the secondary side of the transformer based on a fast Fourier transform algorithm.
In one embodiment, the step of calculating the fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer based on the fast fourier transform algorithm includes:
amplifying the electric energy signal on the secondary side of the transformer into a second square wave signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the second square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the step of amplifying the power signal at the secondary side of the transformer into a second square wave signal further includes:
performing digital-to-analog conversion and sampling on the second square wave signal by integral multiple of the power frequency of the transformer to obtain a second conversion signal;
the step of calculating to obtain the fundamental wave electric energy signal of the secondary side according to the second square wave signal based on the fast Fourier transform algorithm comprises the following steps:
and calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second conversion signal based on a fast Fourier transform algorithm.
A transformer current reduction apparatus, the apparatus comprising:
the primary side current acquisition module is used for acquiring an electric energy signal of the primary side of the transformer;
the secondary side current acquisition module is used for acquiring an electric energy signal of the secondary side of the transformer;
the primary side fundamental wave acquisition module is used for calculating to obtain a primary side fundamental wave electric energy signal according to the primary side electric energy signal of the transformer;
the secondary side fundamental wave acquisition module is used for calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer;
and the transformation ratio calculation module is used for calculating and obtaining the transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the following steps when executing the computer program:
acquiring an electric energy signal of a primary side of a transformer;
acquiring an electric energy signal of the secondary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer;
and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
A computer-readable storage medium, on which a computer program is stored which, when executed by a processor, carries out the steps of:
acquiring an electric energy signal of a primary side of a transformer;
acquiring an electric energy signal of the secondary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer;
and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
According to the transformer current conversion method, the transformer current conversion device, the computer equipment and the storage medium, the primary side electric energy signal and the secondary side electric energy signal of the transformer are respectively collected, and the primary side fundamental wave electric energy signal and the secondary side fundamental wave electric energy signal are obtained through calculation so as to remove the influence of harmonic waves, so that the calculation of the transformation ratio of the transformer is more accurate, and whether the transformer has a fault or not is effectively judged.
Drawings
FIG. 1 is a diagram illustrating an exemplary embodiment of a transformer current reduction method;
FIG. 2 is a schematic flow chart of a method for converting a transformer current according to an embodiment;
FIG. 3 is a block diagram of a transformer current reduction device according to an embodiment;
FIG. 4 is a diagram illustrating an internal structure of a computer device according to an embodiment;
fig. 5 is a schematic diagram of an application environment of the transformer current conversion method in another embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
The transformer current conversion method provided by the application can be applied to the application environment shown in fig. 1. In this embodiment, the number of the electric energy measuring devices is two, one is used for measuring the electric energy signal of the primary side of the transformer, and the other is used for measuring the electric energy signal of the secondary side of the transformer. The detection host machine can be one or two, one detection host machine is respectively connected with two electric energy measuring devices through a network, when the two detection host machines are provided, one of the two detection host machines is a low-voltage terminal extension machine, the other is a high-voltage terminal host machine, the low-voltage terminal extension machine obtains an electric energy signal of the primary side of the transformer through measurement of one electric energy measuring device, and the high-voltage terminal host machine obtains an electric energy signal of the secondary side of the transformer through measurement of the other electric energy measuring device. The low-voltage terminal extension and the high-voltage terminal host can communicate through a wireless network. The detection host may be, but is not limited to, various personal computers or servers, and the server 104 may be implemented by a stand-alone server or a server cluster composed of a plurality of servers. The detection host is used for acquiring an electric energy signal of the primary side of the transformer through the electric energy measuring equipment; acquiring an electric energy signal of the secondary side of the transformer; calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer; calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer; and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
In one embodiment, as shown in fig. 2, there is provided a transformer current reduction method, comprising the steps of:
Specifically, the primary side of the transformer is the high voltage side of the transformer, and the power signal is a three-phase power signal. In this step, three-phase electric energy signals of the high-voltage side of the transformer are acquired. It should be noted that the electric energy signal includes a current signal and a voltage signal, that is, in this embodiment, a three-phase current signal and a three-phase voltage signal of the primary side of the transformer are obtained.
Specifically, the secondary side of the transformer is the low-voltage side of the transformer, and the power signal is a three-phase power signal. In this step, three-phase electric energy signals of the low-voltage side of the transformer are acquired. In this embodiment, a three-phase current signal and a three-phase voltage signal on the secondary side of the transformer are obtained.
And 250, calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer.
In this step, calculation is performed according to the primary-side electric energy signal of the transformer to remove the influence of harmonics in the primary-side electric energy signal of the transformer, and current data of a power frequency fundamental wave, that is, a primary-side fundamental wave electric energy signal, is obtained through calculation. Specifically, the fundamental wave power signal is a fundamental wave part of the power signal on the primary side, that is, the fundamental wave power signal is a power signal in which only the fundamental wave part remains after removing harmonics from the power signal on the primary side.
And 270, calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer.
In this step, calculation is performed according to the electrical energy signal of the secondary side of the transformer to remove the influence of harmonic waves in the electrical energy signal of the secondary side of the transformer, and current data of the power frequency fundamental wave, that is, the fundamental wave electrical energy signal of the secondary side, is obtained through calculation. Specifically, the fundamental wave power signal is a fundamental wave part of the power signal on the primary side, that is, the fundamental wave power signal is a power signal in which only the fundamental wave part remains after removing harmonics from the power signal on the primary side.
And 290, calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
Specifically, the transformation ratio of the transformer is calculated according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side, and whether the transformer has a fault is detected.
It should be noted that the connection groups of the three-phase signals commonly used in the transformer generally include Dyn11 and Yyn0, Dyn11 has the advantage of being beneficial to suppressing higher harmonic current, and for the three-phase transformer with Yyn0 connection, the primary side is star-connected without a neutral line, so that the third harmonic current cannot flow. Therefore, the second harmonic current has a different effect on the calculation results for different connection groups. That is, the mathematical relationship of the harmonic current between the primary side and the secondary side of the transformer is uncertain for different connection groups, and even for the same connection group, the harmonic current makes the mathematical relationship between the primary side and the secondary side of the transformer very complicated. After the influence of harmonic waves is removed, only the current data of the power frequency fundamental wave is calculated, and then, the calculation results are the same for all the connection groups, so that the influence of the harmonic waves on the calculation results can be effectively eliminated
In this embodiment, the electric energy signals of the three phases on the primary side of the transformer and the electric energy signals of the three phases on the secondary side of the transformer are acquired and obtained, and the electric energy signals of each phase of the electric energy signals of the three phases on the primary side of the transformer and the electric energy signals of each phase of the electric energy signals of the three phases on the secondary side of the transformer are respectively calculated to obtain the fundamental wave electric energy signals of each phase on the primary side of the transformer and the fundamental wave electric energy signals of each phase on the secondary side of the transformer. If the current error exceeds the limit, the cause of the fault should be checked for a power outage.
In the above embodiment, the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side of the transformer are obtained by respectively collecting the electric energy signal of the primary side and the electric energy signal of the secondary side of the transformer, so as to remove the influence of harmonics, further make the calculation of the transformation ratio of the transformer more accurate, and effectively determine whether the transformer has a fault.
In one embodiment, the step of calculating a fundamental wave power signal of the primary side according to the power signal of the primary side of the transformer includes: and calculating to obtain a fundamental wave electric energy signal on the primary side according to the electric energy signal on the primary side of the transformer based on a fast Fourier transform algorithm.
In this embodiment, based on a Fast Fourier Transform (FFT) algorithm, the electric energy signal on the primary side of the transformer is calculated to obtain a fundamental wave electric energy signal on the primary side of the transformer. The fast Fourier Transform algorithm is an efficient DFT (Discrete Fourier Transform) algorithm, and is obtained by improving the Discrete Fourier Transform algorithm according to the characteristics of odd, even, imaginary, real, etc. of the Discrete Fourier Transform. The fast fourier transform algorithm may be divided into a time-based extraction algorithm and a frequency-based extraction algorithm, and in this embodiment, the frequency-based extraction algorithm is mainly used. In this embodiment, the fundamental wave electric energy signal on the primary side can be efficiently calculated by the fast fourier transform algorithm to remove the interference of the harmonic wave.
In one embodiment, the step of calculating a fundamental electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer based on the fast fourier transform algorithm includes: amplifying the electric energy signal at the primary side of the transformer into a first square wave signal; and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first square wave signal based on a fast Fourier transform algorithm.
In this embodiment, the power signals of each phase of the power signals of the primary side of the transformer are amplified into square wave signals respectively; and calculating to obtain a fundamental wave electric energy signal on the primary side according to the square wave signal of each phase based on a fast Fourier transform algorithm.
Specifically, one phase of electric energy signals in three phases of electric energy signals on the primary side of the transformer is obtained, the one phase of electric energy signals is compared with a zero level, and then square wave signals are output. By amplifying the electric energy signal into a square wave signal, the subsequent calculation efficiency and calculation precision can be effectively improved.
In one embodiment, the step of calculating a fundamental wave power signal of the secondary side according to the power signal of the secondary side of the transformer includes: and calculating to obtain a fundamental wave electric energy signal of the secondary side of the transformer according to the electric energy signal of the secondary side of the transformer based on a fast Fourier transform algorithm. In this embodiment, the fundamental wave electric energy signal on the primary side can be efficiently calculated by the fast fourier transform algorithm to remove the interference of the harmonic wave.
In one embodiment, the step of calculating a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer based on the fast fourier transform algorithm includes: amplifying the electric energy signal on the secondary side of the transformer into a second square wave signal; and calculating to obtain a fundamental wave electric energy signal on the primary side according to the second square wave signal based on a fast Fourier transform algorithm.
In this embodiment, the electrical energy signal of each phase of the electrical energy signal on the secondary side of the transformer is amplified into a square wave signal; and calculating to obtain a fundamental wave electric energy signal of the secondary side according to the square wave signal of each phase based on a fast Fourier transform algorithm.
Specifically, one phase of electric energy signals in the three phases of electric energy signals on the secondary side of the transformer is obtained, the one phase of electric energy signals is compared with a zero level, and then square wave signals are output. By amplifying the electric energy signal into a square wave signal, the subsequent calculation efficiency and calculation precision can be effectively improved.
In one embodiment, the step of obtaining the power signal of the primary side of the transformer includes: and sampling the signals on the primary side of the transformer by taking the integral multiple of the power frequency of the transformer as a sampling frequency to obtain the electric energy signals on the primary side of the transformer.
Specifically, the power frequency of the transformer is the frequency of the signal of the transformer, and during sampling, the signal on the primary side of the transformer is sampled by using the frequency of the integral multiple of the power frequency of the transformer as the sampling frequency.
In one embodiment, the step of obtaining the power signal at the secondary side of the transformer comprises: and sampling the signal of the secondary side of the transformer by taking the integral multiple of the power frequency of the transformer as a sampling frequency to obtain the electric energy signal of the secondary side of the transformer.
In this embodiment, during sampling, the signal on the secondary side of the transformer is sampled with the frequency of the integral multiple of the power frequency of the transformer as the sampling frequency, so that during calculation of the fast fourier transform algorithm, frequency leakage can be effectively avoided, and the accuracy of the fundamental wave electric energy signal obtained by calculation is the highest.
It should be understood that, although the steps in the flowchart of fig. 2 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least a portion of the steps in fig. 2 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performance of the sub-steps or stages is not necessarily sequential, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.
The following is a specific example:
in this embodiment, as shown in fig. 5, a voltage transformer and a current transformer are disposed on each phase of the primary side of the transformer, and are respectively used for collecting a voltage signal and a current signal of each phase of the transformer, and the secondary side of the transformer is the same. The detection host is provided with an MCU (micro controller Unit), the voltage transformer and the current transformer are respectively connected with the input end of the analog-to-digital converter through the program control amplifier, and the output end of the analog-to-digital converter is connected with the MCU. The detection host is also provided with a communication module, a display module and a keyboard module, the display module and the keyboard module are output modules of the detection host, the communication module is used for being connected with an external terminal, and the external terminal is a detection host on a secondary side.
Firstly, electric energy signals of a primary side and electric energy signals of a secondary side of a transformer are acquired and obtained respectively. In this embodiment, the primary side collects three-phase voltage signals of the transformer through the voltage transformer, and collects three-phase current signals of the transformer through the current transformer.
Then, signal selection is performed to select one signal from six power signals of the primary side at the detection terminal of the primary side, wherein the six power signals are three current signals (I)A、IB、IC) And three voltage signals (U)A、UB、UC). And at the detection terminal of the secondary side, one signal is also selected from six signals of the power signal of the secondary side.
Then, the selectively determined power signal is shaped into a square wave signal, and the power signal is directly amplified into a square wave or is compared with a 0 level to be a square wave. In this embodiment, the electrical energy signal is shaped into a square wave signal by the programmable amplifier.
And then, carrying out phase-locked frequency multiplication on the square wave signal, and carrying out digital-to-analog conversion sampling on the power frequency signal according to integral multiple. The wave of each cycle samples a fixed number of points. Such as 256 or 512 dots. And calculating to obtain a sine table and a cosine table with 256 or 512 points.
For example, 512 frequency multiplication, when the power frequency is 50Hz, the sampling output is 50 × 512 Hz — 25600 Hz. In this embodiment, the MCU starts the dac to sample according to the frequency-doubled signal, so as to ensure synchronous sampling of the six paths of power signals and sampling according to the integer multiple of the power frequency signal. Synchronous sampling can ensure the phase precision of each electric energy signal. It is worth mentioning that, since the measured object is a power signal, its frequency is called power frequency. When the number of the sampling of each cycle is integral multiple of the frequency of the signal to be detected, and the time interval of every two samplings is the same, the FFT operation is carried out according to the multiple, and the frequency leakage can be effectively avoided.
And then, performing FFT operation on the electric energy signal after the digital-to-analog conversion.
It is worth mentioning that the error of calculating the high-voltage side three-phase current becomes large due to the fact that the secondary side electric energy signal of the transformer may contain rich harmonic components.
It should be appreciated that the advantage of having Dyn11 coupled with Yyn0, Dyn11 in the connection group commonly used in the transformer industry is the suppression of higher harmonic currents. For a Yyn0 junction three-phase transformer, the primary side is star-connected without a neutral line, so that third harmonic current cannot flow. Therefore, for different connection groups, the second harmonic current has different influences on the calculation result. That is, the mathematical relationship of the harmonic currents between the primary and secondary of the transformer is uncertain for different connection groups. Even for the same wiring group, the mathematical relationship of the harmonic currents between the primary and secondary of the transformer becomes very complex.
If the influence of harmonic waves is removed, only the current data of the power frequency fundamental wave is calculated, and then the calculation results are the same for all the connection groups.
Specifically, the fundamental wave data is obtained based on the FFT in the following principle:
1. assuming that the voltage and current of the AC is converted into N-bit collection, the collection number ranges from 0 to 2N
2. Assume that the number of N bits collected is { a }0、a1…ak……aN-2、aN-1}
3. Assuming that the real part of the voltage current of the alternating current is a, the imaginary part is B,
then there are:
the magnitude of the current voltage is:
the phase angle of the current voltage is: act (B/A) equation 7
In this embodiment, two dimensional values of the electrical energy signal are calculated to obtain two fundamental wave data, one is amplitude and the other is phase. In this embodiment, a frequency multiplication of 512 is adopted, that is, N is 512.
From equations 4 and 5 above, one can derive:
P＝(sin(2*π*0/N)*K、sin(2*π*1/N)*K、sin(2*π*2/N)*K、……、sin(2*π*511/N)*K)；
q ═ COS (2 × pi × 0/N) × K, COS (2 × pi × 1/N) × K, COS (2 × pi × 2/N) × K, … …, COS (2 × pi × 511/N) × K), where K is a coefficient, corresponding to the amplitude, with the object of expanding the data of the sine (-1 to 1) to (-K to K), so that integer arithmetic can be employed.
PQ is two positive rotation cospinning tables (when 0-511) at 512 points of one cycle.
Sampled data (a)0……a511) Multiplying the data corresponding to P and adding the result to obtain A;
sampled data (a)0……a511) Multiplying the data corresponding to the Q and adding the multiplied data to obtain a result B;
when the period is 512 points, the integral harmonic components except the fundamental wave, the product sum of which with A and B is 0, can be understood as orthogonal.
Thus, the fundamental wave amplitude of the electric energy signal can be calculated according to the formula 6, and the fundamental wave phase angle of the electric energy signal can be calculated according to the formula 7.
The fundamental wave electric energy signal of the primary side is obtained through calculation, the fundamental wave electric energy signal of the secondary side is obtained through calculation by the same method, and then the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side are calculated to obtain a transformation ratio, so that whether the transformer has faults or not can be detected and judged.
In one embodiment, as shown in fig. 3, there is provided a transformer current reduction apparatus including:
the primary side current obtaining module 310 is configured to obtain a power signal at a primary side of the transformer.
A secondary side current obtaining module 330, configured to obtain an electrical energy signal of the secondary side of the transformer.
The primary side fundamental wave obtaining module 350 is configured to calculate and obtain a primary side fundamental wave electric energy signal according to the electric energy signal on the primary side of the transformer.
And a secondary side fundamental wave obtaining module 370, configured to calculate to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer.
And a transformation ratio calculating module 390, configured to calculate a transformation ratio according to the fundamental wave electric energy signal on the primary side and the fundamental wave electric energy signal on the secondary side.
In an embodiment, the primary-side fundamental wave obtaining module is further configured to calculate a primary-side fundamental wave electric energy signal according to the primary-side electric energy signal of the transformer based on a fast fourier transform algorithm.
In one embodiment, the primary-side fundamental wave acquisition module includes:
and a first square wave shaping unit for amplifying the electric energy signal at the primary side of the transformer into a first square wave signal.
And the first fundamental wave electric energy signal acquisition unit is used for calculating to obtain a fundamental wave electric energy signal on the primary side according to the first fundamental wave signal based on a fast Fourier transform algorithm.
In one embodiment, the primary-side fundamental wave acquisition module further includes:
the first sampling unit is used for carrying out digital-to-analog conversion and sampling on the first square wave signal by integral multiple of the power frequency of the transformer to obtain a first conversion signal;
the first fundamental wave electric energy signal acquisition unit is also used for calculating to obtain a fundamental wave electric energy signal on the primary side according to the first conversion signal based on a fast Fourier transform algorithm;
in an embodiment, the secondary-side fundamental wave obtaining module is further configured to calculate to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer based on a fast fourier transform algorithm.
In one embodiment, the secondary-side fundamental acquisition module includes:
and the second square wave shaping unit is used for amplifying the electric energy signal on the secondary side of the transformer into a second square wave signal.
And the second fundamental wave electric energy signal acquisition unit is used for calculating to obtain a fundamental wave electric energy signal on the primary side according to the second square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the secondary-side fundamental acquisition module further includes:
the second sampling unit is used for carrying out digital-to-analog conversion and sampling on the second square wave signal by integral multiple of the power frequency of the transformer to obtain a second conversion signal;
and the second fundamental wave electric energy signal acquisition unit is also used for calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second conversion signal based on a fast Fourier transform algorithm.
For specific limitations of the transformer current conversion device, reference may be made to the above limitations of the transformer current conversion method, and details thereof are not repeated here. The modules in the transformer current conversion device can be wholly or partially realized by software, hardware and a combination thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.
In one embodiment, a computer device is provided, which may be a server, the internal structure of which may be as shown in fig. 4. The computer device includes a processor, a memory, a network interface, and a database connected by a system bus. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device comprises a nonvolatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of an operating system and computer programs in the non-volatile storage medium. The database of the computer device is used for storing data such as network topology information. The network interface of the computer device is used for connecting with the electric energy measuring device through a network and is also used for connecting with other computer devices through the network interface. The computer program is executed by a processor to implement a transformer current conversion method.
Those skilled in the art will appreciate that the architecture shown in fig. 4 is merely a block diagram of some of the structures associated with the disclosed aspects and is not intended to limit the computing devices to which the disclosed aspects apply, as particular computing devices may include more or less components than those shown, or may combine certain components, or have a different arrangement of components.
In one embodiment, a computer device is provided, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor implementing the following steps when executing the computer program:
acquiring an electric energy signal of a primary side of a transformer;
acquiring an electric energy signal of the secondary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer;
and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
In one embodiment, the processor, when executing the computer program, further performs the steps of:
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the electric energy signal on the primary side of the transformer based on a fast Fourier transform algorithm.
In one embodiment, the processor, when executing the computer program, further performs the steps of:
amplifying the electric energy signal at the primary side of the transformer into a first square wave signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the processor, when executing the computer program, further performs the steps of:
performing digital-to-analog conversion and sampling on the first square wave signal by integral multiple of the power frequency of the transformer to obtain a first conversion signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first conversion signal based on a fast Fourier transform algorithm.
In one embodiment, the processor, when executing the computer program, further performs the steps of:
and calculating to obtain a fundamental wave electric energy signal of the secondary side of the transformer according to the electric energy signal of the secondary side of the transformer based on a fast Fourier transform algorithm.
In one embodiment, the processor, when executing the computer program, further performs the steps of:
amplifying the electric energy signal on the secondary side of the transformer into a second square wave signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the second square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the processor, when executing the computer program, further performs the steps of:
performing digital-to-analog conversion and sampling on the second square wave signal by integral multiple of the power frequency of the transformer to obtain a second conversion signal;
and calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second conversion signal based on a fast Fourier transform algorithm.
In one embodiment, a computer-readable storage medium is provided, having a computer program stored thereon, which when executed by a processor, performs the steps of:
acquiring an electric energy signal of a primary side of a transformer;
acquiring an electric energy signal of the secondary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the primary side according to the electric energy signal of the primary side of the transformer;
calculating to obtain a fundamental wave electric energy signal of the secondary side according to the electric energy signal of the secondary side of the transformer;
and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
In one embodiment, the computer program when executed by the processor further performs the steps of:
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the electric energy signal on the primary side of the transformer based on a fast Fourier transform algorithm.
In one embodiment, the computer program when executed by the processor further performs the steps of:
amplifying the electric energy signal at the primary side of the transformer into a first square wave signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the computer program when executed by the processor further performs the steps of:
performing digital-to-analog conversion and sampling on the first square wave signal by integral multiple of the power frequency of the transformer to obtain a first conversion signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first conversion signal based on a fast Fourier transform algorithm.
In one embodiment, the computer program when executed by the processor further performs the steps of:
and calculating to obtain a fundamental wave electric energy signal of the secondary side of the transformer according to the electric energy signal of the secondary side of the transformer based on a fast Fourier transform algorithm.
In one embodiment, the computer program when executed by the processor further performs the steps of:
amplifying the electric energy signal on the secondary side of the transformer into a second square wave signal;
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the second square wave signal based on a fast Fourier transform algorithm.
In one embodiment, the computer program when executed by the processor further performs the steps of:
performing digital-to-analog conversion and sampling on the second square wave signal by integral multiple of the power frequency of the transformer to obtain a second conversion signal;
and calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second conversion signal based on a fast Fourier transform algorithm.
It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).
The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A transformer current reduction method, the method comprising:
acquiring an electric energy signal of a primary side of a transformer;
acquiring an electric energy signal of the secondary side of the transformer;
amplifying the electric energy signal at the primary side of the transformer into a first square wave signal; calculating to obtain a fundamental wave electric energy signal on the primary side according to the first square wave signal based on a fast Fourier transform algorithm; the first square wave signal is output after the electric energy signal of the primary side is compared with zero level;
amplifying the electric energy signal on the secondary side of the transformer into a second square wave signal; calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second square wave signal based on a fast Fourier transform algorithm; the second square wave signal is output after the electric energy signal of the secondary side is compared with a zero level;
and calculating to obtain a transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
2. The method of claim 1, wherein the step of amplifying the power signal at the primary side of the transformer into a first square wave signal is followed by the step of:
performing digital-to-analog conversion and sampling on the first square wave signal by integral multiple of the power frequency of the transformer to obtain a first conversion signal;
the step of calculating to obtain the fundamental wave electric energy signal on the primary side according to the first square wave signal based on the fast fourier transform algorithm is as follows:
and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first conversion signal based on a fast Fourier transform algorithm.
3. The method of claim 1, wherein the step of amplifying the power signal on the secondary side of the transformer into a second square wave signal is followed by the step of:
performing digital-to-analog conversion and sampling on the second square wave signal by integral multiple of the power frequency of the transformer to obtain a second conversion signal;
the step of calculating to obtain the fundamental wave electric energy signal of the secondary side according to the second square wave signal based on the fast Fourier transform algorithm comprises the following steps:
and calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second conversion signal based on a fast Fourier transform algorithm.
4. The method of claim 1, wherein the power signal comprises a current signal and a voltage signal.
5. A transformer current reduction apparatus, comprising:
the primary side current acquisition module is used for acquiring an electric energy signal of the primary side of the transformer;
the secondary side current acquisition module is used for acquiring an electric energy signal of the secondary side of the transformer;
a primary side fundamental wave acquisition module for amplifying the primary side electric energy signal of the transformer into a first square wave signal; calculating to obtain a fundamental wave electric energy signal on the primary side according to the first square wave signal based on a fast Fourier transform algorithm; the first square wave signal is output after the electric energy signal of the primary side is compared with zero level;
the secondary side fundamental wave acquisition module is used for amplifying the electric energy signal of the secondary side of the transformer into a second square wave signal; calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second square wave signal based on a fast Fourier transform algorithm; the second square wave signal is output after the electric energy signal of the secondary side is compared with a zero level;
and the transformation ratio calculation module is used for calculating and obtaining the transformation ratio according to the fundamental wave electric energy signal of the primary side and the fundamental wave electric energy signal of the secondary side.
6. The apparatus of claim 5, wherein the primary-side fundamental acquisition module is configured to perform digital-to-analog conversion and sampling on the first square wave signal by an integer multiple of a power frequency of the transformer to obtain a first converted signal; and calculating to obtain a fundamental wave electric energy signal on the primary side according to the first conversion signal based on a fast Fourier transform algorithm.
7. The apparatus of claim 5, wherein the secondary side current obtaining module is configured to perform digital-to-analog conversion and sampling on the second square wave signal by an integer multiple of a power frequency of the transformer to obtain a second conversion signal; and calculating to obtain a fundamental wave electric energy signal of the secondary side according to the second conversion signal based on a fast Fourier transform algorithm.
8. The apparatus of claim 5, wherein the power signal comprises a current signal and a voltage signal.
9. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the steps of the method of any of claims 1 to 4 are implemented when the computer program is executed by the processor.
10. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the method of any one of claims 1 to 4.
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| US4758774A (en) * | 1985-04-29 | 1988-07-19 | Special Instruments Laboratory, Incorporated | Portable tester and related method for determining the primary winding to secondary winding current ratio of an in-service current transformer |
| JPH09182293A (en) * | 1995-12-26 | 1997-07-11 | Hitachi Ltd | Controller for power converter |
| JP4429146B2 (en) * | 2004-11-17 | 2010-03-10 | 新電元工業株式会社 | DC / DC converter |
| CN102412747A (en) * | 2010-09-25 | 2012-04-11 | 中国江南航天工业集团林泉电机厂 | Method and device for converting direct current into alternating current |
| CN201869149U (en) * | 2010-11-25 | 2011-06-15 | 杭州三和电控设备有限公司 | DSP-based synchronous generator excitation regulator |
| CN104865455B (en) * | 2015-06-23 | 2018-02-09 | 江苏省电力公司苏州供电公司 | Distribution transformer no-load voltage ratio measuring instrument and its measuring method |
| CN105242135B (en) * | 2015-09-24 | 2018-01-12 | 国网山东省电力公司莱芜供电公司 | Three-phase power transformer on-line parameter identification device and its realize algorithm |
| CN105388444B (en) * | 2015-12-28 | 2018-03-27 | 武汉大学 | The capacitance type potential transformer harmonic measure bearing calibration being fitted using no-load voltage ratio |
| CN106053940B (en) * | 2016-08-09 | 2018-04-10 | 重庆大学 | A kind of harmonic analysis method decomposed based on square wave Fourier space |
| CN206269943U (en) * | 2016-08-31 | 2017-06-20 | 北京浩坤科技有限公司 | Vibratory string collecting device |
| CN206531895U (en) * | 2017-01-16 | 2017-09-29 | 哈尔滨理工大学 | Harmonic measurement device based on DSP and virtual instrument |
| CN108872919B (en) * | 2018-07-13 | 2021-01-05 | 中国三冶集团有限公司 | Debugging method for transformation ratio of zero-sequence current transformer on low-voltage side of transformer |
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