CN106326653A - Data processing method and data processing device for predicting current - Google Patents

Abstract

The invention discloses a data processing method and a data processing device for predicting current. The method comprises the following steps of determining a plurality of target loads; predicting current waveforms of the plurality of target loads working in an electric power system according to a preset algorithm. According to the data processing method and the data processing system disclosed by the invention, the problem of whether the electric power system needs over-current protection or not is judged by a method of predicting a current effective value is easy to mistake in the related art is solved.

Description

Data processing method and device for predicted current

Technical field

The present invention relates to data processing field, in particular to a kind of data processing method for predicted current and Device.

Background technology

Current forecasting refers to when power system not being put into concrete load, it was predicted that if multiple load works at the same time Current conditions in power system.Current forecasting is very important for prevention power system overload and overcurrent protection.Existing Having in technology, the main method being predicted the electric current in power system is all based on power signal, according to I=P/U, by respectively The rated power of individual load, derives the virtual value of electric current when all loads work at the same time.Only the virtual value of electric current is carried out Prediction can not judge the concrete condition of electric current in power system, and this is all the most unfavorable to overcurrent protection and harmonic wave control etc. , easily cause overcurrent protection error in judgement.

Judge that power system is volatile the need of overcurrent protection for the method for predicted current virtual value in correlation technique Problem, the most not yet proposes effective solution by mistake.

Summary of the invention

Present invention is primarily targeted at a kind of data processing method for predicted current of offer and device, to solve phase In the technology of pass, in correlation technique, the method for predicted current virtual value judges what power system was easily slipped up the need of overcurrent protection Problem.

To achieve these goals, according to an aspect of the invention, it is provided a kind of at the data of predicted current Reason method.The method comprises determining that multiple target load；Multiple target loads work in power system is predicted according to preset algorithm Current waveform when making.

Further, multiple target loads include the first load, determine that multiple target load includes: detect the first load Electric current；The current harmonics formula of the first load is determined according to testing result.

Further, it is determined that multiple target loads include: determine the current harmonics formula of each target load respectively, according in advance If current waveform when the multiple target load of algorithm predicts works in power system comprises determining that the power supply electricity of power system Pressure；Supply voltage according to power system and the current harmonics formula of each target load determine the current waveform of combined stress, its In, combined stress is the load that multiple target load is compounded to form.

Further, it is determined that the supply voltage of power system comprises determining that the voltage first phase of the supply voltage of power system Angle, determines the current waveform bag of combined stress according to the supply voltage of power system and the current harmonics formula of each target load Include: determine the first-harmonic initial phase angle of each target load respectively according to the current harmonics formula of each target load；Respectively according to each The first-harmonic initial phase angle of target load and the voltage initial angle of supply voltage determine the phase between each target load and supply voltage Potential difference；Current harmonics formula according to the phase contrast between each target load and supply voltage and each target load determines compound The current waveform of load.

Further, the electric current according to the phase contrast between each target load and supply voltage and each target load is humorous Waves determines that the current waveform of combined stress comprises determining that the weight coefficient of each target load；According to each target load The current harmonics formula of weight coefficient, phase contrast between each target load and supply voltage and each target load determines compound The current harmonics formula of load；Current harmonics formula according to combined stress determines the current waveform of combined stress.

To achieve these goals, according to an aspect of the invention, it is provided a kind of at the data of predicted current Reason device.This device comprises determining that unit, is used for determining multiple target load；Predicting unit, for predicting according to preset algorithm Current waveform when multiple target loads work in power system.

Further, multiple target loads include the first load, determine that unit includes: detection module, for detection first The electric current of load；First determines module, for determining the current harmonics formula of the first load according to testing result.

Further, the first current harmonics formula determining module to be additionally operable to respectively to determine each target load, it was predicted that unit Including: second determines module, for determining the supply voltage of power system；3rd determines module, for according to power system The current harmonics formula of supply voltage and each target load determines the current waveform of combined stress, and wherein, combined stress is multiple The load that target load is compounded to form.

Further, second determines that module is additionally operable to determine the voltage initial angle of the supply voltage of power system, and the 3rd is true Cover half block is additionally operable to: first determines submodule, for determining each target according to the current harmonics formula of each target load respectively The first-harmonic initial phase angle of load；Second determines submodule, for respectively according to first-harmonic initial phase angle and the power supply electricity of each target load The voltage initial angle of pressure determines the phase contrast between each target load and supply voltage；3rd determines submodule, for basis Phase contrast between each target load and supply voltage and the current harmonics formula of each target load determine the electricity of combined stress Stream waveform.

Further, the 3rd determines that submodule is additionally operable to: determine the weight coefficient of each target load；According to each target The current harmonics formula of the weight coefficient of load, the phase contrast between each target load and supply voltage and each target load is true Determine the current harmonics formula of combined stress；Current harmonics formula according to combined stress determines the current waveform of combined stress.

The present invention is determined by multiple target load；Multiple target loads work in power system is predicted according to preset algorithm Current waveform when making, the method for predicted current virtual value in correlation technique that solves judges that power system is the need of overcurrent The problem of protection easily error, by predicted current waveform rather than the virtual value of only calculating current, and then judges electric power more accurately System is the need of overcurrent protection.

Accompanying drawing explanation

The accompanying drawing of the part constituting the application is used for providing a further understanding of the present invention, and the present invention's is schematic real Execute example and illustrate for explaining the present invention, being not intended that inappropriate limitation of the present invention.In the accompanying drawings:

Fig. 1 is the flow chart of the data processing method for predicted current according to embodiments of the present invention；

Fig. 2 is the waveform diagram of multiple target loads according to embodiments of the present invention；

Fig. 3 is the waveform diagram of predicted current according to embodiments of the present invention and measured current；

Fig. 4 is the schematic diagram of the data processing equipment for predicted current according to embodiments of the present invention.

Detailed description of the invention

It should be noted that in the case of not conflicting, the embodiment in the application and the feature in embodiment can phases Combination mutually.Describe the present invention below with reference to the accompanying drawings and in conjunction with the embodiments in detail.

In order to make those skilled in the art be more fully understood that the application scheme, below in conjunction with in the embodiment of the present application Accompanying drawing, is clearly and completely described the technical scheme in the embodiment of the present application, it is clear that described embodiment is only The embodiment of the application part rather than whole embodiments.Based on the embodiment in the application, ordinary skill people The every other embodiment that member is obtained under not making creative work premise, all should belong to the model of the application protection Enclose.

It should be noted that term " first " in the description and claims of this application and above-mentioned accompanying drawing, " Two " it is etc. for distinguishing similar object, without being used for describing specific order or precedence.Should be appreciated that so use Data can exchange in the appropriate case, in order to embodiments herein described herein.Additionally, term " includes " and " tool Have " and their any deformation, it is intended that cover non-exclusive comprising, such as, contain series of steps or unit Process, method, system, product or equipment are not necessarily limited to those steps or the unit clearly listed, but can include the most clear That list to Chu or for intrinsic other step of these processes, method, product or equipment or unit.

The embodiment provides a kind of data processing method for predicted current.

Fig. 1 is the flow chart of the data processing method for predicted current according to embodiments of the present invention.As it is shown in figure 1, The method comprises the following steps:

Step S101, determines multiple target load.

The data processing method for predicted current that this embodiment provides is for predicting that above-mentioned multiple target load exists When power system works simultaneously, the current conditions in power system, such as, virtual value, waveform etc..In order to predict power system In current conditions, need first to determine multiple target load.

Determine that multiple target load can be by obtaining the kind of multiple target loads or detecting multiple target load The mode such as electrical quantity determine.Such as, receive the kind of multiple target loads of input, determine often according to the kind of target load The current harmonics formula of individual target load, or, detect the electric current of multiple target load, obtain the practical measurement of current ripple of target load Shape, determines the electric current of each target load according to the respective measured waveform of multiple target loads.

Step S102, current waveform when working in power system according to the preset algorithm multiple target loads of prediction.

After determining multiple target load, when predicting that multiple target load works in power system by preset algorithm Current waveform.Virtual value compared to only predicted current, it was predicted that current waveform can instruct the life of power system more accurately Produce work, extremely important to prevention system overload and overcurrent protection.

The preset algorithm that prediction is used can be to determine according in the way of determining multiple target load, such as, by connecing Receiving the mode of the kind of multiple target loads of input, preset algorithm can be that the kind according to multiple target loads determines respectively The current harmonics formula of each target load, is overlapped further according to current harmonics formula, obtains the waveform of prediction.

The data processing method for predicted current that this embodiment provides, is determined by multiple target load；According in advance Current waveform when if the multiple target load of algorithm predicts works in power system, solving predicted current in correlation technique has The method of valid value judges the problem that power system is easily slipped up the need of overcurrent protection, by predicted current waveform rather than only counts Calculate the virtual value of electric current, and then judge that power system is the need of overcurrent protection more accurately.

Multiple target loads include that the first load, the first load can represent any one in multiple target load and bear Lotus, determines that the mode of multiple target load can be to detect the electric current of the first load, determines the first load according to testing result Current harmonics formula.Wherein, testing result can be the current value detected in preset time period, determines electric current according to current value Waveform, determines that according to testing result the current harmonics formula of the first load can be the current value and current waveform obtained by detection The anti-current harmonics formula releasing the first load.

Determine multiple target load to include respectively to determine the current harmonics formula of each target load, predict according to preset algorithm Current waveform when multiple target loads work in power system can determine that the supply voltage of power system, further according to electricity The supply voltage of Force system and the current harmonics formula of each target load determine the current waveform of combined stress, wherein, Compound Negative Lotus is the load that multiple target load is compounded to form.

Preferably, determine at the beginning of the voltage that the supply voltage of power system may include that the supply voltage determining power system Phase angle, determines the current waveform bag of combined stress according to the supply voltage of power system and the current harmonics formula of each target load Include: determine the first-harmonic initial phase angle of each target load respectively according to the current harmonics formula of each target load；Respectively according to each The first-harmonic initial phase angle of target load and the voltage initial angle of supply voltage determine the phase between each target load and supply voltage Potential difference；Current harmonics formula according to the phase contrast between each target load and supply voltage and each target load determines compound The current waveform of load.

Preferably, according to the phase contrast between each target load and supply voltage and the current harmonics of each target load Formula determines that the current waveform of combined stress can determine that the weight coefficient of each target load；Power according to each target load The current harmonics formula of weight coefficient, phase contrast between each target load and supply voltage and each target load determines Compound Negative The current harmonics formula of lotus；Current harmonics formula according to combined stress determines the current waveform of combined stress.

Below in conjunction with the specific embodiment data processing method for predicted current to the embodiment of the present invention Illustrate:

From Fourier analysis theory, when supply voltage meets GB, the steady-state current of load can use fundamental current Electric current superposition with each harmonic represents, then load electric current in certain is measured is represented by following formula:

i_t=a₁·sin(ωt+θ₁)+a₂·sin(2·ωt+θ₂)+…+a_k·sin(k·ωt+θ_k) (1)

In formula, a_kFor the amplitude of kth harmonic wave, ω is first-harmonic angular frequency (being 50*2*pi during power frequency), θ_kMeasure for this The initial phase angle of middle kth harmonic wave, its value is relevant with the waveform segment intercepted during Fourier analysis.

Use exchange entry, if x=is ω t+ θ₁, then have ω t=x-θ₁, by ω t=x-θ₁Bring the expression formula of kth harmonic wave into Then there is a following formula:

i_t(k)=a_k·sin(k·(x-θ₁)+θ_k)=a_k·sin(k·x+(-k·θ₁+θ_k)) (2)

If the reference initial phase of fundamental phase is θ_CIf, x=ω t+ θ_C, △ θ_k=-k θ₁+θ_k,

By x=ω t+ θ_CWith Δ θ_k=-k·θ₁+θ_kSubstitution formula (2), and be generalized to formula (1), then have

i_t=a₁·sin(ωt+θ_C)+…+a_kSin (k. ω t+k θ_C+Δθ_k) (3)

Formula (3) is the complete mathematical model of single current waveform, wherein Δ θ_kDetermine the phase of kth harmonic wave and first-harmonic To position, have cured whole waveform, and θ_CDetermine the movement in x-axis of the whole waveform, have no effect on the shape of whole waveform.

Owing to same class load has identical appearance perception, therefore under identical supply voltage, θ_CAlso it is identical, because of When these two same load work under power-frequency voltage simultaneously, its waveform is the twice of single load waveform.But different loads Owing to being likely to be of different appearance perception, its first-harmonic initial phase angle is also likely to be different, when working simultaneously can not directly superposition, but First-harmonic initial phase angle is a definite value relative to the difference of voltage initial angle, and therefore taking certain voltage initial angle θ measured is reference Angle, by the θ in formula (3)_CReplace with θ+θ_C, now, θ_CPhysical significance be to hold the fundamental current that brings of perception due to load With the phase contrast of voltage, formula (3) becomes:

i_t=a₁·sin(ωt+θ+θ_C)+…+a_k·sin(k·ωt+k·(θ+θ_C)+Δθ_k) (4)

For a combined stress waveform being made up of n load, following formula is had to set up:

I_t=β₁i_t1+β₂i_t2+…+β_ni_tn (5)

In formula, β_nBe the weight coefficient of the n-th type load, i.e. load quantity, have again:

i_tn=a_1n.sin (ω t+ θ+θ_Cn)+…+a_kn.sin (k ω t+k. (θ+θ_Cn)+Δθ_kn) (6)

According to formula (6), formula (5) is expressed as matrix form is:

$I_t=\left[\begin{array}{cccc}{a}_{11}\∠\mathrm{\θ}+{\mathrm{\θ}}_{C1}& a_{12}\∠\mathrm{\θ}+{\mathrm{\θ}}_{C2}& \mathrm{...}& a_{1n}\∠\mathrm{\θ}+{\mathrm{\θ}}_{Cn}\\ a_{21}\∠2\·(\mathrm{\θ}+{\mathrm{\θ}}_{C1})+{\mathrm{\Δ\θ}}_{21}& a_{22}\∠2\·(\mathrm{\θ}+{\mathrm{\θ}}_{C2})+{\mathrm{\Δ\θ}}_{22}& \mathrm{...}& a_{2n}\∠2\·(\mathrm{\θ}+{\mathrm{\θ}}_{Cn})+{\mathrm{\Δ\θ}}_{2n}\\ .& .& .& .\\ .& .& .& .\\ .& .& .& .\\ a_{k1}\∠k\·(\mathrm{\θ}+{\mathrm{\θ}}_{C1})+{\mathrm{\Δ\θ}}_{k1}& a_{k2}\∠k\·(\mathrm{\θ}+{\mathrm{\θ}}_{C2})+{\mathrm{\Δ\θ}}_{k2}& \mathrm{...}& a_{kn}\∠k\·(\mathrm{\θ}+{\mathrm{\θ}}_{Cn})+{\mathrm{\Δ\θ}}_{kn}\end{array}\right]\left[\begin{array}{c}{\mathrm{\β}}_1\\ {\mathrm{\β}}_2\\ .\\ .\\ .\\ {\mathrm{\β}}_n\end{array}\right]---\left(7\right)$

In formula (7), Δ θ_kn、_Cn、a_knIt is the known quantity recorded, these known quantities have cured single load waveform Shape and the relative position of different load waveform；θ is fixed phase angle, determines the composite wave-shape position in x-axis；β is each Plant the weight coefficient of load, i.e. load quantity, determine the net shape of composite wave-shape.

Formula (7) is the complete mathematical model of many loads Waveform forecast, can be denoted as:

I_t=A B (8)

In formula (8), A is characterized parameter matrix, contains the position between shape information and the different wave of single waveform Information；B is weight coefficient matrix, determines the quantity of each load in composite wave-shape.

Electric current after adding multiple load in power system is carried out Waveform forecast i.e.: set B, according to the A tried to achieve, Seek final waveform I_t, now the θ in A can be set to arbitrary value, and when the initial phase angle that θ is voltage, the waveform predicted is Real current waveform under this supply voltage.

The scene applying above-described embodiment is as follows:

Existing to 1,2,3, the waveform that measures of 4 four kind of load as in figure 2 it is shown, according to the Wave data recorded, by height Precision FFT records Δ θ_kn、θ_Cn、a_kn, and to take with reference to angle, θ be 0, constitutive characteristic parameter matrix A, adds negative in power system Lotus 1, load 3, each one of load 4, load 2 six, i.e. take B=1 611^T, then obtain predicted current in power system and The waveform of measured current as shown in Figure 3, is found out by Fig. 3, this embodiment the current waveform being predicted and the electricity of actual measurement Stream waveform is sufficiently close to.

Definition waveform difference δ is:

$\mathrm{\δ}=\frac{\underset{i=1}{\overset{i=7}{\Σ}}abs\left(\right({\mathrm{CH}}_{1i}-{\mathrm{CH}}_{2i})/{\mathrm{CH}}_{2i})}{7}\·100\%---\left(9\right)$

In formula, CH_1iAnd CH_2iBeing respectively prediction waveform and seven features in one cycle of actual measurement, these seven features are respectively For peak value, absolute mean, virtual value, form factor, crest factor, peak-to-average force ratio, low all than.

Being calculated the above-mentioned waveform difference predicted the outcome is 2.67%, and explanation can well predict respective waveforms, adopts The data processing method for predicted current provided by this embodiment predicts that many load currents waveform is very effective.

It should be noted that can be at such as one group of computer executable instructions in the step shown in the flow chart of accompanying drawing Computer system performs, and, although show logical order in flow charts, but in some cases, can be with not It is same as the step shown or described by order execution herein.

Embodiments of the invention additionally provide a kind of data processing equipment for predicted current.It should be noted that this The data processing equipment for predicted current of inventive embodiments may be used for performing the data for predicted current of the present invention Processing method.

Fig. 4 is the schematic diagram of the data processing equipment for predicted current according to embodiments of the present invention.As shown in Figure 4, This device includes determining unit 10 and predicting unit 20.

Determine that unit 10 is for determining multiple target load.

Current wave when predicting unit 20 is for working in power system according to the preset algorithm multiple target loads of prediction Shape.

The data processing equipment for predicted current that this embodiment provides, is determined by multiple target load；According in advance Current waveform when if the multiple target load of algorithm predicts works in power system, solving predicted current in correlation technique has The method of valid value judges the problem that power system is easily slipped up the need of overcurrent protection, by predicted current waveform rather than only counts Calculate the virtual value of electric current, and then judge that power system is the need of overcurrent protection more accurately.

Alternatively, multiple target loads include the first load, determine that unit includes: detection module, negative for detection first The electric current of lotus；First determines module, for determining the current harmonics formula of the first load according to testing result.

Alternatively, the first current harmonics formula determining module to be additionally operable to respectively to determine each target load, it was predicted that unit bag Include: second determines module, for determining the supply voltage of power system；3rd determines module, for the confession according to power system The current harmonics formula of piezoelectric voltage and each target load determines the current waveform of combined stress, and wherein, combined stress is multiple mesh The load that mark load is compounded to form.

Alternatively, second determines that module is additionally operable to determine the voltage initial angle of the supply voltage of power system, and the 3rd determines Module is additionally operable to: first determines submodule, for determining that each target is born according to the current harmonics formula of each target load respectively The first-harmonic initial phase angle of lotus；Second determines submodule, for respectively according to first-harmonic initial phase angle and the supply voltage of each target load Voltage initial angle determine the phase contrast between each target load and supply voltage；3rd determines submodule, for according to every Phase contrast between individual target load and supply voltage and the current harmonics formula of each target load determine the electric current of combined stress Waveform.

Alternatively, the 3rd determines that submodule is additionally operable to: determine the weight coefficient of each target load；Bear according to each target The current harmonics formula of the weight coefficient of lotus, the phase contrast between each target load and supply voltage and each target load determines The current harmonics formula of combined stress；Current harmonics formula according to combined stress determines the current waveform of combined stress.

Obviously, those skilled in the art should be understood that each module of the above-mentioned present invention or each step can be with general Calculating device realize, they can concentrate on single calculating device, or be distributed in multiple calculating device and formed Network on, alternatively, they can with calculate the executable program code of device realize, it is thus possible to by they store Performed by calculating device in the storage device, or they are fabricated to respectively each integrated circuit modules, or by them In multiple modules or step be fabricated to single integrated circuit module and realize.So, the present invention be not restricted to any specifically Hardware and software combines.

The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for the skill of this area For art personnel, the present invention can have various modifications and variations.All within the spirit and principles in the present invention, that is made any repaiies Change, equivalent, improvement etc., should be included within the scope of the present invention.

Claims (10)

1. the data processing method for predicted current, it is characterised in that including:

Determine multiple target load；

Current waveform when working in power system according to the preset algorithm the plurality of target load of prediction.

Method the most according to claim 1, it is characterised in that the plurality of target load includes the first load, determines many Individual target load includes:

Detect the electric current of described first load；

The current harmonics formula of described first load is determined according to testing result.

Method the most according to claim 2, it is characterised in that

Determine that multiple target load includes: determine the current harmonics formula of each target load respectively,

Current waveform when working in power system according to the preset algorithm the plurality of target load of prediction comprises determining that described The supply voltage of power system；Supply voltage and the current harmonics formula of each target load according to described power system determine multiple Closing the current waveform of load, wherein, described combined stress is the load that the plurality of target load is compounded to form.

Method the most according to claim 3, it is characterised in that

Determine that the supply voltage of described power system comprises determining that the voltage initial angle of the supply voltage of described power system,

Supply voltage according to described power system and the current harmonics formula of each target load determine the current wave of combined stress Shape includes: determine the first-harmonic initial phase angle of each target load respectively according to the current harmonics formula of each target load；Basis respectively The first-harmonic initial phase angle of each target load and the voltage initial angle of described supply voltage determine each target load and described power supply Phase contrast between voltage；According to the phase contrast between each target load and described supply voltage and the electricity of each target load Stream harmonic determines the current waveform of described combined stress.

Method the most according to claim 4, it is characterised in that according between each target load and described supply voltage The current harmonics formula of phase contrast and each target load determines that the current waveform of described combined stress includes:

Determine the weight coefficient of each target load；

Phase contrast between weight coefficient according to each target load, each target load and described supply voltage and each mesh The current harmonics formula of mark load determines the current harmonics formula of described combined stress；

Current harmonics formula according to described combined stress determines the current waveform of described combined stress.

6. the data processing equipment for predicted current, it is characterised in that including:

Determine unit, be used for determining multiple target load；

Predicting unit, current wave during for working in power system according to the preset algorithm the plurality of target load of prediction Shape.

Device the most according to claim 6, it is characterised in that the plurality of target load includes the first load, described really Cell includes:

Detection module, for detecting the electric current of described first load；

First determines module, for determining the current harmonics formula of described first load according to testing result.

Device the most according to claim 7, it is characterised in that

Described first determines module to be additionally operable to respectively determines the current harmonics formula of each target load,

Described predicting unit includes: second determines module, for determining the supply voltage of described power system；3rd determines mould Block, for determining the electric current of combined stress according to the supply voltage of described power system and the current harmonics formula of each target load Waveform, wherein, described combined stress is the load that the plurality of target load is compounded to form.

Device the most according to claim 8, it is characterised in that

Described second determines that module is additionally operable to determine the voltage initial angle of the supply voltage of described power system,

Described 3rd determines that module is additionally operable to: first determines submodule, for respectively according to the current harmonics of each target load Formula determines the first-harmonic initial phase angle of each target load；Second determines submodule, for respectively according to the first-harmonic of each target load The voltage initial angle of initial phase angle and described supply voltage determines the phase contrast between each target load and described supply voltage；The Three determine submodule, for according to the phase contrast between each target load and described supply voltage and the electricity of each target load Stream harmonic determines the current waveform of described combined stress.

Device the most according to claim 9, it is characterised in that the described 3rd determines that submodule is additionally operable to:

Determine the weight coefficient of each target load；

Phase contrast between weight coefficient according to each target load, each target load and described supply voltage and each mesh The current harmonics formula of mark load determines the current harmonics formula of described combined stress；

Current harmonics formula according to described combined stress determines the current waveform of described combined stress.