CN104101781B - Substation bus bar voltage phase angle instantaneous value measuring method - Google Patents

Abstract

The invention discloses a kind of substation bus bar voltage phase angle instantaneous value measuring method.First the instantaneous voltage of each sampling instant of substation bus bar voltage is measured, calculate the steady coefficient of the substation bus bar voltage of each sampling instant, calculate the slide coefficient of the substation bus bar voltage of each sampling instant, calculate the substation bus bar electric voltage frequency instantaneous value of each sampling instant, then calculate the substation bus bar voltage phase angle instantaneous value of each sampling instant.The certainty of measurement of the inventive method is not by aperiodicity noise impact, data window is short, operand is little, algorithm fast operation, can the most accurately measure the substation bus bar voltage phase angle instantaneous value of each sampling instant, can be the real-time peak-frequency regulation of complex large power grid and electric network swim Real-Time Scheduling offer scientific basis.

Description

Substation bus bar voltage phase angle instantaneous value measuring method

Technical field

The present invention relates to power system safety and stability and control technical field, concretely relate to one not by non- The substation bus bar voltage phase angle instantaneous value measuring method of periodic noise effect of signals.

Background technology

Realize electrical network each substation bus bar voltage phase angle accurately to measure, can be peak load regulation network frequency modulation and electrical network tide Stream scheduling provides scientific basis.Power industry mainly utilizes Fourier algorithm to calculate substation bus bar voltage at present Phase angle, the method hypotheses substation bus bar voltage phase angle keeps stable within a 20ms cycle Constant, utilize a cycle data amount to extract real part and the imaginary part of substation bus bar voltage, recycle transformer station The real part of busbar voltage calculates, with imaginary part, the tangent value that substation bus bar voltage phase angle is corresponding, then carries out anti- Tangent transformation calculations substation bus bar voltage phase angle.Due to Fourier algorithm own limitations, desired data Window is a cycle, and desired data window is long, and operand is big, and arithmetic speed is slow, and measurement result also can only be reacted One cycle voltage phase angle, it is impossible to measure the substation bus bar voltage phase angle of each sampling instant in real time.By Aperiodicity noise impact cannot be filtered so that certainty of measurement is by aperiodicity noise in Fourier algorithm Effect of signals is serious, it is impossible to meet complex large power grid peak-frequency regulation and the needs of electric network swim scheduling.

Summary of the invention

It is an object of the invention to the deficiency overcoming prior art to exist, it is provided that a kind of substation bus bar voltage phase Parallactic angle instantaneous value measuring method, the certainty of measurement of the method is not by aperiodicity noise impact, data window Short, operand is little, algorithm fast operation, can the most accurately measure the substation bus bar electricity of each sampling instant Pressure phase angle instantaneous value, can be the real-time peak-frequency regulation of complex large power grid and electric network swim Real-Time Scheduling offer science Foundation.

For completing above-mentioned purpose, the present invention adopts the following technical scheme that

Substation bus bar voltage phase angle instantaneous value measuring method, including following sequential steps:

(1) instantaneous voltage of each sampling instant of substation bus bar voltage is measured；

(2) the steady coefficient of the substation bus bar voltage of t sampling instant is calculated Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant；(t-k Δ t) is the change of t-k Δ t sampling instant to u Power station busbar voltage sampled value；(t+k Δ t) is the substation bus bar voltage sample value of t+k Δ t sampling instant to u；Δ t is Sampling interval duration；K is data window length, and is positive integer；

(3) slide coefficient of the substation bus bar voltage of t sampling instant is calculated

Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant； (t-k Δ t) is the substation bus bar voltage sample value of t-k Δ t sampling instant to u；(t+k Δ t) is t+k Δ t sampling instant to u Substation bus bar voltage sample value；Δ t is sampling interval duration；K is data window length, and is positive integer；

(4) the substation bus bar electric voltage frequency f of calculating t sampling instant:

$f=\frac{1}{2\mathrm{\πk\Δt}}{\cos }^{-1}\left(\frac{\underset{i=-m}{\overset{i=m}{\mathrm{\Σ}}}|\frac{u(t+\mathrm{i\Δt}+\mathrm{k\Δt})}{\sqrt{{\left[u(t+\mathrm{i\Δt}+\mathrm{k\Δt})\right]}^2-{\left[u(t+\mathrm{i\Δt})u(t+\mathrm{i\Δt}+2\mathrm{k\Δt})\right]}^2}}+\frac{u(t+\mathrm{i\Δt}-\mathrm{k\Δt})}{\sqrt{{\left[u(t+\mathrm{i\Δt}-\mathrm{k\Δt})\right]}^2-{\left[u(t+\mathrm{i\Δt})u(t+\mathrm{i\Δt}-2\mathrm{k\Δt})\right]}^2}}|}{\underset{i=-m}{\overset{i=m}{\mathrm{\Σ}}}\frac{2u(t+\mathrm{i\Δt})}{\sqrt{{\left[u(t+\mathrm{i\Δt})\right]}^2-{\left[u(t+\mathrm{i\Δt}+\mathrm{k\Δt})u(t+\mathrm{i\Δt}-\mathrm{k\Δt})\right]}^2}}}\right)$

Wherein, (t+i Δ t) is the substation bus bar voltage sample value of t+i Δ t sampling instant to u；(t+i Δ t-k Δ t) is that t+i Δ t-k Δ t adopts to u The substation bus bar voltage sample value in sample moment；(t+i Δ t+k Δ t) is the substation bus bar of t+i Δ t+k Δ t sampling instant to u Voltage sample value；Δ t is sampling interval duration；K is data window length, and is positive integer；(t+i Δ t-2k Δ t) is u The substation bus bar voltage sample value of t+i Δ t-2k Δ t sampling instant；(t+i Δ t+2k Δ t) is t+i Δ t+2k Δ t sampling instant to u Substation bus bar voltage sample value；I is integer quotient；M is weighting length；

(5) the substation bus bar voltage phase angle of t sampling instant is calculated

$\mathrm{\θ}={\cos }^{-1}\left(\frac{u\left(t\right)\sqrt{\underset{i=1}{\overset{i=k}{\mathrm{\Σ}}}(1-{\cos }^2\left(2\mathrm{\πfi\Δt}\right))}}{\sqrt{\underset{i=1}{\overset{i=k}{\mathrm{\Σ}}}({\left[u\left(t\right)\right]}^2-{\left[u(t+\mathrm{i\Δt})u(t-\mathrm{i\Δt})\right]}^2)}}\right)-100\mathrm{\πt};$

Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant；(t-i Δ t) is the change of t-i Δ t sampling instant to u Power station busbar voltage sampled value；(t+i Δ t) is the substation bus bar voltage sample value of t+i Δ t sampling instant to u；Δ t is Sampling interval duration；K is data window length, and is positive integer；I is integer quotient.

The present invention compared with prior art, has a following positive achievement:

The certainty of measurement of the inventive method is not by aperiodicity noise impact, and data window is short, and operand is little, Algorithm fast operation, the substation bus bar voltage phase angle that can the most accurately measure each sampling instant is instantaneous Value, can be the real-time peak-frequency regulation of complex large power grid and electric network swim Real-Time Scheduling offer scientific basis.

Accompanying drawing explanation

Fig. 1 is the two-terminal transmission systems schematic diagram of the application present invention.

Detailed description of the invention

Below according to Figure of description, technical scheme is expressed in further detail.

Fig. 1 is the two-terminal transmission systems schematic diagram of the application present invention.In Fig. 1, PT is substation bus bar voltage Transformer.

Substation bus bar voltage phase angle instantaneous value measuring method, comprises the following steps:

(1) voltage phase angle instantaneous value measurement apparatus measures each sampling instant of substation bus bar voltage in real time Instantaneous voltage.

(2) the substation bus bar voltage of voltage phase angle instantaneous value measurement apparatus calculating t sampling instant is steady Coefficient

$\sqrt{{\left[u\left(t\right)\right]}^2-{\left[u(t-\mathrm{k\Δt})u(t+\mathrm{k\Δt})\right]}^2}$

Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant；(t-k Δ t) is t-k Δ t sampling instant to u Substation bus bar voltage sample value；(t+k Δ t) is the substation bus bar voltage sample value of t+k Δ t sampling instant to u； Δ t is sampling interval duration；K is data window length, and is positive integer.

(3) slip of the substation bus bar voltage of voltage phase angle instantaneous value measurement apparatus calculating t sampling instant Coefficient

$\frac{u\left(t\right)}{\sqrt{{\left[u\left(t\right)\right]}^2-{\left[u(t-\mathrm{k\Δt})u(t+\mathrm{k\Δt})\right]}^2}}$

Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant；(t-k Δ t) is t-k Δ t sampling instant to u Substation bus bar voltage sample value；(t+k Δ t) is the substation bus bar voltage sample value of t+k Δ t sampling instant to u； Δ t is sampling interval duration；K is data window length, and is positive integer.

(4) the substation bus bar electric voltage frequency f of voltage phase angle instantaneous value measurement apparatus calculating t sampling instant:

$f=\frac{1}{2\mathrm{\πk\Δt}}{\cos }^{-1}\left(\frac{\underset{i=-m}{\overset{i=m}{\mathrm{\Σ}}}|\frac{u(t+\mathrm{i\Δt}+\mathrm{k\Δt})}{\sqrt{{\left[u(t+\mathrm{i\Δt}+\mathrm{k\Δt})\right]}^2-{\left[u(t+\mathrm{i\Δt})u(t+\mathrm{i\Δt}+2\mathrm{k\Δt})\right]}^2}}+\frac{u(t+\mathrm{i\Δt}-\mathrm{k\Δt})}{\sqrt{{\left[u(t+\mathrm{i\Δt}-\mathrm{k\Δt})\right]}^2-{\left[u(t+\mathrm{i\Δt})u(t+\mathrm{i\Δt}-2\mathrm{k\Δt})\right]}^2}}|}{\underset{i=-m}{\overset{i=m}{\mathrm{\Σ}}}\frac{2u(t+\mathrm{i\Δt})}{\sqrt{{\left[u(t+\mathrm{i\Δt})\right]}^2-{\left[u(t+\mathrm{i\Δt}+\mathrm{k\Δt})u(t+\mathrm{i\Δt}-\mathrm{k\Δt})\right]}^2}}}\right)$

Wherein, (t+i Δ t) is the substation bus bar voltage sample value of t+i Δ t sampling instant to u；(t+i Δ t-k Δ t) is that t+i Δ t-k Δ t adopts to u The substation bus bar voltage sample value in sample moment；(t+i Δ t+k Δ t) is the substation bus bar of t+i Δ t+k Δ t sampling instant to u Voltage sample value；Δ t is sampling interval duration；K is data window length, and is positive integer；(t+i Δ t-2k Δ t) is u The substation bus bar voltage sample value of t+i Δ t-2k Δ t sampling instant；(t+i Δ t+2k Δ t) is t+i Δ t+2k Δ t sampling instant to u Substation bus bar voltage sample value；I is integer quotient；M is weighting length；

(5) voltage phase angle instantaneous value measurement apparatus calculates the substation bus bar voltage phase angle of t sampling instant

$\mathrm{\θ}={\cos }^{-1}\left(\frac{u\left(t\right)\sqrt{\underset{i=1}{\overset{i=k}{\mathrm{\Σ}}}(1-{\cos }^2\left(2\mathrm{\πfi\Δt}\right))}}{\sqrt{\underset{i=1}{\overset{i=k}{\mathrm{\Σ}}}({\left[u\left(t\right)\right]}^2-{\left[u(t+\mathrm{i\Δt})u(t-\mathrm{i\Δt})\right]}^2)}}\right)-100\mathrm{\πt}$

Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant；(t-i Δ t) is the change of t-i Δ t sampling instant to u Power station busbar voltage sampled value；(t+i Δ t) is the substation bus bar voltage sample value of t+i Δ t sampling instant to u；Δ t is Sampling interval duration；K is data window length, and is positive integer；I is integer quotient.

The substation bus bar voltage phase angle of voltage phase angle instantaneous value measurement apparatus output t sampling instant is instantaneous Value result of calculation.

The certainty of measurement of the inventive method is not by aperiodicity noise impact, and data window is short, and operand is little, Algorithm fast operation, the substation bus bar voltage phase angle that can the most accurately measure each sampling instant is instantaneous Value, can be the real-time peak-frequency regulation of complex large power grid and electric network swim Real-Time Scheduling offer scientific basis.

The foregoing is only the preferred embodiment of the present invention, but protection scope of the present invention is not limited to This, any those familiar with the art, in the technical scope that the invention discloses, can readily occur in Change or replacement, all should contain within protection scope of the present invention.

Claims (1)

1. substation bus bar voltage phase angle instantaneous value measuring method, it is characterised in that include as follows Sequential steps:

(1) instantaneous voltage of each sampling instant of substation bus bar voltage is measured；

(2) the steady coefficient of the substation bus bar voltage of t sampling instant is calculated

Wherein, u (t) is the substation bus bar voltage sample value of t sampling instant； (t-k Δ t) is the substation bus bar voltage sample value of t-k Δ t sampling instant to u；U is (when t+k Δ t) is t+k Δ t sampling The substation bus bar voltage sample value carved；Δ t is sampling interval duration；K is data window length, and is Positive integer；

(3) slide coefficient of the substation bus bar voltage of t sampling instant is calculated

$\frac{u\left(t\right)}{\sqrt{{\[u\left(t\right)\]}^2-{\[u(t-k\mathrm{\Δ}t)u(t+k\mathrm{\Δ}t)\]}^2}};$

(4) the substation bus bar electric voltage frequency f of calculating t sampling instant:

$f=\frac{1}{2\mathrm{\π}k\mathrm{\Δ}t}{\cos }^{-1}\left(\frac{\underset{i=-m}{\overset{i=m}{\mathrm{\Σ}}}|\frac{u\left(t+i\mathrm{\Δ}t+k\mathrm{\Δ}t\right)}{\sqrt{{\[u\left(t+i\mathrm{\Δ}t+k\mathrm{\Δ}t\right)\]}^2-{\[u\left(t+i\mathrm{\Δ}t\right)u\left(t+i\mathrm{\Δ}t+2k\mathrm{\Δ}t\right)\]}^2}}+\frac{u\left(t+i\mathrm{\Δ}t-k\mathrm{\Δ}t\right)}{\sqrt{{\[u\left(t+i\mathrm{\Δ}t-k\mathrm{\Δ}t\right)\]}^2-{\[u\left(t+i\mathrm{\Δ}t\right)u\left(t+i\mathrm{\Δ}t-2k\mathrm{\Δ}t\right)\]}^2}}}{\underset{i=-m}{\overset{i=m}{\mathrm{\Σ}}}\frac{2u\left(t+i\mathrm{\Δ}t\right)}{\sqrt{{\[u\left(t+i\mathrm{\Δ}t\right)\]}^2-{\[u\left(t+i\mathrm{\Δ}t+k\mathrm{\Δ}t\right)u\left(t+i\mathrm{\Δ}t-k\mathrm{\Δ}t\right)\]}^2}}}\right)$

(t+i Δ t-2k Δ t) is the substation bus bar voltage sample value of t+i Δ t-2k Δ t sampling instant to u；(t+i Δ t+2k Δ t) is u The substation bus bar voltage sample value of t+i Δ t+2k Δ t sampling instant；I is integer quotient；M is long for weighting Degree；

(5) the substation bus bar voltage phase angle of t sampling instant is calculated

$\mathrm{\θ}={\cos }^{-1}\left(\frac{u\left(t\right)\sqrt{\underset{i=1}{\overset{i=k}{\Σ}}(1-{\cos }^2(2\mathrm{\π}fi\mathrm{\Δ}t\left)\right)}}{\sqrt{\underset{i=1}{\overset{i=k}{\Σ}}({\[u\left(t\right)\]}^2-{\[u\left(t+i\mathrm{\Δ}t\right)u\left(t-i\mathrm{\Δ}t\right)\]}^2)}}\right)-100\mathrm{\π}t.$