Harmonic Early Warning Device and Method

Abstract

The present invention relates to the technical field of power consumption monitoring, and in particular to a harmonic warning device and a warning method. The harmonic warning device of the present invention realizes the recording of the bus current waveform, and obtains the harmonic pollution situation of the entire line through the bus current waveform. When the bus is polluted, the current waveforms of each feeder line in the same period are further obtained through the communication module, and the waveforms obtained through the communication module are analyzed to determine the feeder line that generates harmonic pollution, and warns the line to carry out harmonic pollution treatment. The harmonic warning device of the present invention performs harmonic analysis based on data, and through the clock module, ensures the accuracy of the acquired data in the time interval, making the final result more accurate and reliable.

Description

Technical Field

[0001] The present invention relates to the technical field of power consumption monitoring, and particularly to a harmonic warning device and method. Background Art

[0002] A non-linear load refers to a load containing a rectifying device. In an electronic circuit, the voltage and current do not have a linear relationship, and during the input and operation of the load, the relationship between voltage and current often changes. By non-linear, it means that there is no linear relationship between the independent variable and the dependent variable, but a curve or other relationship. Common typical non-linear loads include: soft starters, switching power supplies, UPSs, inverter components, battery chargers, motors with variable frequency control, electronic data image devices, controllable lighting devices, rectifiers, fluorescent lamps, etc.

[0003] From the above examples, we can see that non-linear loads are widely used in production and life.

[0004] The use of a large number of non-linear loads has led to an increasingly serious harmonic pollution of the power grid, the power quality of the power grid has deteriorated day by day, and the technical requirements for dealing with power system harmonics are also getting higher and higher. In the prior art, although a large amount of power consumption data has been collected and recorded, however, the degree of development and application based on the power consumption data is relatively low, especially in terms of mining harmonic pollution data.

[0005] Based on this, in view of the problem of harmonic pollution in the power grid, it is necessary to develop and design a harmonic warning device and method. Summary of the Invention

[0006] The embodiments of the present invention provide a harmonic warning device and method, which are used to solve the problem that there is a lack of technical means for mining and discovering harmonic pollution from power consumption data in the prior art.

[0007] In a first aspect, the embodiments of the present invention provide a harmonic warning device, including:

[0008] a processor, a storage medium, a communication module, and a clock source; the storage medium, the communication module, and the clock source are respectively electrically connected to the processor; the clock source is used to provide a time signal;

[0009] the processor is used to store the acquired first current waveform and the corresponding moment of the first current waveform into the storage medium, and the first current waveform is the current waveform of the busbar;

[0010] the processor is further used to determine whether there is harmonic pollution in the busbar according to the first current waveform;

[0011] If there is harmonic pollution in the busbar, the processor is further configured to determine the feeder line that generates harmonic pollution according to the second current waveform set obtained by the communication module, and send a warning message to the feeder line that generates harmonic pollution. The second current waveform set includes second current waveforms corresponding to each moment of the first current waveform, and the second current waveform is the current waveform of the feeder line connected to the busbar.

[0012] In a possible implementation manner, the clock source includes: a clock holding module and a clock calibration module;

[0013] The clock calibration module is electrically connected to the clock holding module, and the clock holding module is electrically connected to the processor;

[0014] The clock calibration module is configured to obtain the current time according to a predetermined time interval, and calibrate the clock holding module according to the current time;

[0015] The clock calibration module is configured to generate a time signal.

[0016] In a possible implementation manner, the clock calibration module obtains the current time through a navigation satellite.

[0017] In a possible implementation manner, the harmonic warning device further includes: a current acquisition module, the current acquisition module is signal-connected to the processor, and the current acquisition module is configured to acquire the current of the busbar.

[0018] In a second aspect, an embodiment of the present invention provides a harmonic warning method, including: obtaining a first current waveform and a moment corresponding to the first current waveform, where the first current waveform is the current waveform of the busbar;

[0019] Determining the pollution degree of the busbar according to the first current waveform;

[0020] If the pollution degree exceeds a first threshold, obtaining a second waveform set according to the moment corresponding to the first current waveform. The second current waveform set includes second current waveforms corresponding to each moment of the first current waveform, and the second current waveform is the current waveform of the feeder line connected to the busbar;

[0021] Determining the feeder line that generates harmonic pollution according to the second current waveform set;

[0022] Sending a warning message to the monitoring module of the feeder line.

[0023] In a possible implementation manner, the obtaining the first current waveform includes:

[0024] Sample the current of the busbar to obtain instantaneous currents at multiple different times;

[0025] Fit the instantaneous currents at multiple different times in chronological order to obtain the first current waveform.

[0026] In a possible implementation manner, determining the pollution degree of the busbar according to the first current waveform includes:

[0027] Perform Fourier transform on the first current waveform to obtain a fundamental wave and multiple high-order harmonics;

[0028] Obtain the amplitude of the fundamental wave according to the fundamental wave, and obtain the amplitudes of the high-order harmonics according to each of the high-order harmonics;

[0029] Calculate the ratio of the amplitude of the first high-order harmonic to the amplitude of the fundamental wave as the pollution degree of the busbar, where the first high-order harmonic is the harmonic with the largest amplitude among the multiple high-order harmonics.

[0030] In a possible implementation manner, the moments corresponding to the first current waveform include: the start time of the first current waveform and the duration of the first current waveform. Obtaining the second waveform set according to the moments corresponding to the first current waveform includes:

[0031] Obtain the identifiers of the monitoring modules of each feeder line, where the feeder line is a feeder line connected to the busbar;

[0032] Obtain each second current waveform according to the identifier and the moments corresponding to the first current waveform.

[0033] In a possible implementation manner, determining the feeder line that generates harmonic pollution according to the second current waveform set includes:

[0034] Obtain the order of the first high-order harmonic;

[0035] Perform Fourier transform on each second current waveform to obtain the amplitude of the second high-order harmonic, where the second high-order harmonic is the harmonic with the same order as the first high-order harmonic;

[0036] Select the feeder line with the largest amplitude of the second high-order harmonic from each feeder line as the feeder line that generates harmonic pollution.

[0037] In a possible implementation manner, the warning message includes at least one of the following: the moments corresponding to the first current waveform, the order of the harmonic that generates harmonic pollution, the phase angle of the harmonic that generates harmonic pollution, and the amplitude of the harmonic that generates harmonic pollution.

[0038] The beneficial effects of the embodiments of the present invention compared with the prior art are as follows:

[0039] The harmonic warning device according to the embodiments of the present invention realizes the recording of the bus current waveform, obtains the harmonic pollution situation of the entire line through the bus current waveform. When the bus is polluted, the current waveforms of each feeder line in the same period are further obtained through the communication module, and the waveforms obtained through the communication module are analyzed to determine the feeder line generating harmonic pollution, and the line is warned to perform harmonic pollution control. The harmonic warning device of the present invention performs harmonic analysis based on data, and through the clock module, ensures the accuracy of the obtained data in the time interval, making the final result more accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the prior art descriptions will be briefly introduced below. Obviously, the drawings in the following descriptions are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 is a typical power grid architecture diagram provided by the embodiments of the present invention;

[0042] Figure 2 is a functional block diagram of the harmonic warning device provided by the embodiments of the present invention;

[0043] Figure 3 is a flowchart of the harmonic warning method provided by the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] In the following description, specific details such as specific system structures and technologies are proposed for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of the present invention. However, those skilled in the art should understand that the present invention can also be implemented in other embodiments without these specific details. In other cases, the detailed descriptions of well-known systems, devices, and methods are omitted to avoid unnecessary details from interfering with the description of the present invention.

[0045] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following will be described through specific embodiments with reference to the drawings.

[0046] The following details the embodiments of the present invention. This example is implemented on the premise of the technical solution of the present invention, and detailed implementation manners and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.

[0047] Figure 1A typical power grid architecture is shown. In the figure, a plurality of feeders 102 are connected to the bus 101. The feeders 102 are connected to the electrical loads 103 to supply power to the loads 103. When the load 103 in one of the feeders 102 generates harmonics, the entire power grid is contaminated by harmonics.

[0048] Since the harmonic pollution caused by any load 103 is reflected in the bus 101, in the embodiment of the present invention patent, by acquiring the current waveform of the bus 101, it is determined whether harmonic pollution occurs and the pollution degree. When the pollution degree is about to exceed the treatment capacity of the bus 101, then by acquiring the current waveform of the feeder 102 and analyzing the current waveform of the feeder 102, the feeder line where the load 103 generating harmonic pollution is located is determined, so as to realize the positioning of the pollution source.

[0049] The following will be described in detail with reference to the accompanying drawings.

[0050] Figure 2 It is a functional block diagram of the harmonic warning device provided by the embodiment of the present invention.

[0051] As Figure 2 shown, a harmonic warning device, characterized in that it includes: a processor, a storage medium, a communication module, and a clock source; the storage medium, the communication module, and the clock source are respectively electrically connected to the processor; the clock source is used to provide a time signal;

[0052] The processor is used to store the acquired first current waveform and the corresponding moment of the first current waveform into the storage medium, and the first current waveform is the current waveform of the bus.

[0053] The processor is also used to determine whether there is harmonic pollution in the bus according to the first current waveform.

[0054] If there is harmonic pollution in the bus, the processor is also used to determine the feeder line where the harmonic pollution occurs according to the second current waveform set acquired by the communication module and send a warning message to the feeder line where the harmonic pollution occurs. The second current waveform set includes each second current waveform at the same moment as the first current waveform, and the second current waveform is the current waveform of the feeder line connected to the bus.

[0055] Exemplarily, the so-called processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0056] In one implementation, the processor uses a DSP (Digital Signal Processor). Specifically, it is a DSP of the TMS320 series produced by Texas Instruments. The DSP has advantages in terms of speed when performing mathematical operations. For example, when implementing digital filters, they can generally be divided into two categories: finite impulse response type and infinite impulse response type, and can be implemented in both hardware and software ways. In the hardware implementation, it consists of units such as adders and multipliers, which is completely different from the analog filters composed of resistors, inductors, and capacitors. Digital signal processing systems can be easily made with digital integrated circuits, showing advantages such as small size, high stability, and programmability. When implementing the Fourier transform, it is based on the fast algorithm for the discrete Fourier transform first proposed by J.W. Cooley and T.W. Tukey in 1965, abbreviated as the fast Fourier transform, i.e., FFT. Since the fast algorithm appeared, the number of operations of the discrete Fourier transform has been greatly reduced, making the implementation of digital signal processing possible. The fast Fourier transform can also be used for a series of related fast operations, such as correlation, convolution, power spectrum, etc. The fast Fourier transform can be made into a hardware device.

[0057] The storage medium may be the internal storage unit of the processor. For example, the processor integrates a memory and a running memory internally. The storage medium may also be an external storage device of the processor. For example, Smart Media Card (SMC), Secure Digital (SD) card, Flash Card, etc.

[0058] Furthermore, the storage medium is used to store the computer program and other programs and data required by the terminal. The storage medium can also be used to temporarily store the data that has been output or will be output.

[0059] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the implementation method can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method implementation method, which will not be repeated here.

[0060] The clock of the processor comes from a clock source, which is a precise clock source. In the implementation mode of the present invention, the processor needs to process the signals of the bus and the feeder line, and the two need to obtain a strict time correspondence. For example, in an application scenario, after obtaining certain parameters from the waveform of the current passing through the bus, it is also necessary to obtain the waveform of the current of the feeder line in the same time period. Since the current waveform of the power grid changes very quickly, even if it is an ideal waveform, its frequency can reach more than 50Hz. Accurate time is a prerequisite for obtaining correct data and performing accurate calculations. One implementation mode of the clock source is to use a constant temperature crystal oscillator and calibrate it regularly through the network to keep the time of the bus and the feeder line precisely consistent.

[0061] There are many ways to implement the communication module. When it is set up at short distances, common methods such as wired network cards, WiFi communication modules or RS485 communication modules can be used. For application scenarios that require remote transmission, 4G or 5G communication modules can be used to access the Internet through telecommunications networks to achieve remote data transmission.

[0062] In the embodiment of the present invention, the processor obtains the waveform of the current of the bus and stores the waveform in the storage medium to realize the recording of the current waveform. The bus also analyzes the current waveform to determine whether the bus is polluted. As mentioned above, when the feeder is polluted, the bus will inevitably be polluted. By analyzing the pollution of the bus, the pollution of the entire line can be reflected.

[0063] When there is pollution on the busbar, the processor will obtain the current waveforms of each feeder line connected to the busbar through the communication module. Note that the waveforms of the currents of the above-mentioned feeders are the waveforms of the same period as the currents during the harmonic pollution analysis of the busbar. After analyzing the feeder current waveforms one by one, the feeder line that generates harmonic pollution can be determined, and then a warning message is sent to the monitoring module of the feeder line, so that the feeder line can carry out harmonic control in a timely and targeted manner.

[0064] The harmonic early warning device of the present invention realizes the recording of the busbar current waveform, and obtains the harmonic pollution situation of the entire line through the busbar current waveform. When the busbar is polluted, the current waveforms of the same period of each feeder line are further obtained through the communication module, and the waveforms obtained through the communication module are analyzed to determine the feeder line that generates harmonic pollution, and the line is warned to carry out harmonic pollution control. The harmonic early warning device of the present invention performs harmonic analysis based on data, and through the clock module, ensures the accuracy of the obtained data in the time interval, making the final result more accurate and reliable.

[0065] In some embodiments, the clock source includes: a clock holding module and a clock calibration module;

[0066] The clock calibration module is electrically connected to the clock holding module, and the clock holding module is electrically connected to the processor;

[0067] The clock calibration module is used to obtain the current time according to a predetermined time interval, and calibrate the clock holding module according to the current time;

[0068] The clock calibration module is used to generate a time signal.

[0069] In some embodiments, in a possible implementation manner, the clock calibration module obtains the current time through a navigation satellite.

[0070] Exemplarily, as mentioned above, the clock source is a prerequisite for ensuring the consistency of the time intervals of the busbar current waveform and the feeder current waveform. In one embodiment, a clock holding module and a clock calibration module are adopted.

[0071] The clock holding module continuously generates a clock signal. One way that can be adopted is a temperature-controlled crystal oscillator. The temperature-controlled crystal oscillator eliminates the influence of temperature on the time accuracy. Nevertheless, the cumulative error during long-term operation is still unacceptable. Therefore, a clock calibration module is also provided. The clock calibration module is used to obtain a precise time. For example, in one embodiment, the time is obtained from a navigation satellite. The time of the navigation satellite is guaranteed. The navigation satellite using a cesium atomic clock can ensure that there is a deviation of only one second in at least several hundred years. This accuracy can meet the requirements of the embodiments of the present invention.

[0072] Adopting the combination of the clock holding module and the clock calibration module can not only ensure the clock accuracy of the system, but also ensure the overall economy of the system, which is an economical and reliable implementation method.

[0073] In some embodiments, the harmonic warning device further includes: a current acquisition module, the current acquisition module is signal-connected to the processor, and the current acquisition module is used to acquire the current of the bus.

[0074] Exemplarily, the current acquisition module is used to acquire the current of the bus. One implementation method is a sampling module with a current transformer as the core, which acquires the current of the bus, performs analog-to-digital conversion on the current, and converts it into a digital signal that can be accepted by the processor.

[0075] The second aspect of the embodiments of the present invention provides a harmonic warning method. Figure 3 The flowchart of the harmonic warning method is shown.

[0076] The following is combined with the attached Figure 3 for explanation.

[0077] In step 301, the obtaining of the first current waveform includes: obtaining the first current waveform and the corresponding moment, and the first current waveform is the current waveform of the bus.

[0078] In some embodiments, in step 301, the obtaining of the first current waveform includes:

[0079] Sampling the current of the bus to obtain instantaneous currents at multiple different moments;

[0080] Fitting the instantaneous currents at multiple different moments in chronological order to obtain the first current waveform.

[0081] Exemplarily, as described in the first aspect, by obtaining the sampling of the bus current through the current acquisition module, the data density of the sampling data is usually small. Therefore, after obtaining the data, the current is fitted by a fitting method to generate a current waveform.

[0082] Sampling based on the fitted current waveform can obtain a higher density of sampling points, achieving the effect of expanding the data set.

[0083] In step 302, determine the pollution degree of the bus according to the first current waveform.

[0084] In some embodiments, in step 302, determining the pollution degree of the bus according to the first current waveform includes:

[0085] Performing Fourier transform on the first current waveform to obtain the fundamental wave and multiple high-order harmonics;

[0086] Obtain the amplitude of the fundamental wave according to the fundamental wave, and obtain the amplitudes of the higher harmonics according to each of the higher harmonics;

[0087] Calculate the ratio of the amplitude of the first higher harmonic to the amplitude of the fundamental wave as the contamination degree of the busbar, where the first higher harmonic is the harmonic with the largest amplitude among the multiple higher harmonics.

[0088] Exemplarily, determine the contamination degree of the busbar according to the current of the busbar.

[0089] One determination method is to perform a Fourier transform on the current waveform of the busbar to obtain the fundamental wave and higher harmonics.

[0090] Usually based on the possibility of actual higher harmonics occurring and the calculation amount, take the first 20 - 50 higher harmonics. For example, in one application scenario, obtain the first 30 higher harmonics.

[0091] Then, obtain the amplitudes of the fundamental wave and each higher harmonic, sort the amplitudes of each higher harmonic, obtain the amplitude of the higher harmonic with the highest amplitude, the ratio of this amplitude to the fundamental wave is used as the contamination degree of the busbar, and the harmonic with the largest amplitude is used as the harmonic of harmonic pollution. For the treatment of harmonic pollution in the feeder line, it should mainly target this harmonic.

[0092] In step 303, if the contamination degree exceeds the first threshold, then obtain a second waveform set according to the moment corresponding to the first current waveform. The second current waveform set includes each second current waveform at the same moment as the first current waveform, and the second current waveform is the current waveform of the feeder line connected to the busbar.

[0093] In some embodiments, in step 303, the moment corresponding to the first current waveform includes: the start time of the first current waveform and the duration of the first current waveform. Obtaining the second waveform set according to the moment corresponding to the first current waveform includes:

[0094] Obtain the identifiers of the monitoring modules of each feeder line, where the feeder line is the feeder line connected to the busbar;

[0095] Obtain each second current waveform according to the identifier and the moment corresponding to the first current waveform.

[0096] Exemplarily, for the determination of harmonic pollution in the feeder line, it is obtained by analyzing the current waveform within the same time period as the busbar current waveform.

[0097] Therefore, for obtaining the current waveform of the feeder line, it is carried out through the following steps:

[0098] Obtain the identifiers of the monitoring modules of each feeder line. This identifier is the basis for communication. After obtaining the identifier, the current waveform of each feeder line can be obtained one by one.

[0099] When obtaining the waveform of the feeder line, the current waveform in the same time period as the bus current waveform is obtained. Based on the current waveform in this time period for analysis, the feeder line causing harmonic pollution to the bus current waveform can be determined.

[0100] In step 304, determine the feeder line that generates harmonic pollution according to the second set of current waveforms.

[0101] In some embodiments, in step 304, determining the feeder line that generates harmonic pollution according to the second set of current waveforms includes:

[0102] Obtain the order of the first high-order harmonic;

[0103] Perform Fourier transform on each of the second current waveforms to obtain the amplitude of the second high-order harmonic, where the second high-order harmonic is the harmonic with the same order as the first high-order harmonic;

[0104] Select the feeder line with the largest amplitude of the second high-order harmonic from each feeder line as the feeder line that generates harmonic pollution.

[0105] Exemplarily, in some embodiments, while determining that the bus generates harmonic pollution, the order of the harmonic that generates this harmonic pollution can also be determined.

[0106] For each feeder line, analysis should also be performed on this harmonic, such as determining the amplitude of this harmonic in the current of each feeder line.

[0107] In one embodiment, perform Fourier transform on the current waveform of each feeder line. Note that the current waveform of the feeder line should be in the same time period as the bus current waveform. After transformation, obtain the amplitude of the harmonic with the same order as the harmonic that generates harmonic pollution as the amplitude of the second high-order harmonic.

[0108] Sort the amplitudes of the second high-order harmonics of each feeder line to obtain the largest amplitude. This line is also used as the feeder line that generates harmonic pollution and a warning should be given, and subsequent treatment should be carried out.

[0109] In step 305, send a warning message to the monitoring module of the feeder line.

[0110] In some embodiments, the warning message includes at least one of the following: the moment corresponding to the first current waveform, the order of the harmonic that generates harmonic pollution, the phase angle of the harmonic that generates harmonic pollution, and the amplitude of the harmonic that generates harmonic pollution.

[0111] After determining the feeder line causing harmonic pollution, a warning message should be sent to the feeder line.

[0112] The warning message includes: the moment corresponding to the first current waveform, the order of the harmonics causing harmonic pollution, the phase angle of the harmonics causing harmonic pollution, and the amplitude of the harmonics causing harmonic pollution.

[0113] After obtaining the warning message, the feeder line should targetedly control the harmonics, such as disconnecting each main load, or taking passive control measures, or taking active control measures.

[0114] When taking active control measures, the steps of obtaining the main parameters of the harmonics causing harmonic pollution are essential. The main parameters include: the moment corresponding to the first current waveform, the order of the harmonics causing harmonic pollution, the phase angle of the harmonics causing harmonic pollution, and the amplitude of the harmonics causing harmonic pollution.

[0115] In the above embodiments, the descriptions of each embodiment have their own focuses. For the parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0116] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0117] In the embodiments provided by the present invention, it should be understood that the disclosed device / terminal and method can be implemented in other ways. For example, the device / terminal embodiments described above are only illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of the devices or units can be in electrical, mechanical or other forms.

[0118] The unit described as a separation component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, that is, it may be located in one place or distributed over multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0119] In addition, each functional unit in various embodiments of the present invention can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0120] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above-described method of the embodiment can also be completed by a computer program instructing relevant hardware. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above-described embodiments of each harmonic warning device and harmonic warning method can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0121] The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of each embodiment of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A harmonic warning device, characterized in that, Including: A processor, a storage medium, a communication module, and a clock source; The storage medium, the communication module, and the clock source are respectively electrically connected to the processor; The clock source is used to provide a time signal; The processor is used to store the acquired first current waveform and the corresponding moment of the first current waveform into the storage medium, and the first current waveform is the current waveform of the bus; The processor is further used to determine whether there is harmonic pollution on the bus according to the first current waveform; If there is harmonic pollution on the bus, the processor is further used to determine the feeder line that generates harmonic pollution according to the second current waveform set acquired by the communication module and send a warning message to the feeder line that generates harmonic pollution. The second current waveform set includes second current waveforms corresponding to each moment of the first current waveform, and the second current waveform is the current waveform of the feeder line connected to the bus. Among them, determining whether there is harmonic pollution on the bus according to the first current waveform includes: determining the pollution degree of the bus according to the first current waveform; Among them, determining the pollution degree of the bus according to the first current waveform includes: Performing Fourier transform on the first current waveform to obtain a fundamental wave and multiple high-order harmonics; Obtaining the amplitude of the fundamental wave according to the fundamental wave, and obtaining the amplitudes of the high-order harmonics according to each of the high-order harmonics; Calculating the ratio of the amplitude of the first high-order harmonic to the amplitude of the fundamental wave as the pollution degree of the bus, and the first high-order harmonic is the harmonic with the largest amplitude among the multiple high-order harmonics; Among them, determining the feeder line that generates harmonic pollution according to the second current waveform set acquired by the communication module includes: Obtaining the order of the first high-order harmonic; Performing Fourier transform on each of the second current waveforms to obtain the amplitude of the second high-order harmonic, and the second high-order harmonic is the harmonic with the same order as the first high-order harmonic; Selecting the feeder line with the largest amplitude of the second high-order harmonic from each feeder line as the feeder line that generates harmonic pollution.

2. The harmonic warning device according to claim 1, characterized in that, The clock source includes: a clock holding module and a clock calibration module; The clock calibration module is electrically connected to the clock holding module, and the clock holding module is electrically connected to the processor; The clock calibration module is used to obtain the current time according to a predetermined time interval and calibrate the clock holding module according to the current time; The clock calibration module is used to generate a time signal.

3. The harmonic warning device according to claim 2, characterized in that, The clock calibration module obtains the current time through a navigation satellite.

4. The harmonic warning device according to any one of claims 1-3, characterized in that, It further includes: A current acquisition module, the current acquisition module is signal-connected to the processor, and the current acquisition module is used to collect the current of the bus.

5. A harmonic warning method, characterized in that, Applied to the harmonic warning device according to any one of claims 1-4, the harmonic warning method includes: Obtaining a first current waveform and the corresponding moment of the first current waveform, and the first current waveform is the current waveform of the bus; Determining the pollution degree of the bus according to the first current waveform; If the pollution degree exceeds the first threshold, a second set of current waveforms is obtained according to the moments corresponding to the first current waveform. The second set of current waveforms includes second current waveforms corresponding to the same moments as the first current waveform, and the second current waveform is the current waveform of the feeder line connected to the busbar; Determine the feeder line that generates harmonic pollution according to the second set of current waveforms; Send a warning message to the monitoring module of the feeder line; Among them, the determining the pollution degree of the busbar according to the first current waveform includes: Perform Fourier transform on the first current waveform to obtain a fundamental wave and multiple high-order harmonics; Obtain the amplitude of the fundamental wave according to the fundamental wave, and obtain the amplitudes of the multiple high-order harmonics according to each of the high-order harmonics; Calculate the ratio of the amplitude of the first high-order harmonic to the amplitude of the fundamental wave as the pollution degree of the busbar, and the first high-order harmonic is the harmonic with the largest amplitude among the multiple high-order harmonics; Among them, the determining the feeder line that generates harmonic pollution according to the second set of current waveforms obtained by the communication module includes: Obtain the order of the first high-order harmonic; Perform Fourier transform on each of the second current waveforms to obtain the amplitude of the second high-order harmonic, and the second high-order harmonic is the harmonic with the same order as the first high-order harmonic; Select the feeder line with the largest amplitude of the second high-order harmonic from each feeder line as the feeder line that generates harmonic pollution.

6. The harmonic warning method according to claim 5, wherein, The obtaining the first current waveform includes: Sample the current of the busbar to obtain instantaneous currents at multiple different moments; Fit the instantaneous currents at multiple different moments in chronological order to obtain the first current waveform.

7. The harmonic warning method according to claim 5, wherein, The moments corresponding to the first current waveform include: the start time of the first current waveform and the duration of the first current waveform. The obtaining the second set of current waveforms according to the moments corresponding to the first current waveform includes: Obtain the identifiers of the monitoring modules of each feeder line, and the feeder line is the feeder line connected to the busbar; Obtain each second current waveform according to the identifier and the moments corresponding to the first current waveform.

8. The harmonic warning method according to any one of claims 5-7, wherein, The warning message includes at least one of the following: the moments corresponding to the first current waveform, the order of the harmonic that generates harmonic pollution, the phase angle of the harmonic that generates harmonic pollution, and the amplitude of the harmonic that generates harmonic pollution.

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