CN105627904A - Method for determining deformation of transformer winding - Google Patents

Abstract

The invention discloses a method for determining the deformation of a transformer winding, and the method comprises the steps: S1, obtaining a current impedance sweep frequency curve and an original impedance sweep frequency curve of the transformer winding in a preset frequency range; S2, obtaining the current measurement data of all measurement points according to the current impedance sweep frequency curve; S3, judging whether the measurement points are extreme points or not according to the current measurement data; S4, enabling the extreme points to be stored in an extreme point set if the measurement points are extreme points; S5, judging whether there is a continuous extreme point in the extreme point set or not: switching to step S6 if there is the continuous extreme point in the extreme point set, or else, switching to step S8; S6, eliminating the continuous extreme point in the extreme point set; S7, carrying out the smoothening of the measurement data in a frequency range with the extreme point being eliminated, and returning to step S3; S8, carrying out analysis according to the extreme points in the extreme point set, so as to judge the degree of the deformation of the transformer winding. Therefore, the method avoids the processing of ineffective data in the above process, reduces the workload of calculation, and improves the efficiency.

Description

A kind of decision method of deformation of transformer winding

Technical field

The present invention relates to transformer ' s type Condition Detection and assessment technology field, particularly relate to the decision method of a kind of deformation of transformer winding.

Background technology

Power transformer is one of equipment important in power system, and its safe operation directly affects the safety and reliability of power supply. Along with the increase day by day of net capacity, capacity of short circuit also increases therewith, and the transformer damage accident that short trouble causes is in rising trend. And the deformation of transformer winding caused because of external short circuit, it is again the most common failure in transformator running, the safe operation of system in serious threat. When transformator is impacted by short-circuit current in running, very big short circuit current will be flow through in Transformer Winding, short circuit current is under the interaction with stray field, produce very big electric power, at this moment each winding is by bearing huge, uneven radial direction electric power and axial electric power, thus causing transformer fault.

The existing decision method for deformation of transformer winding mainly has frequency sweep impedance method and frequency response analysis, both based on the decision method of the frequency individual features of winding port. Such as, by whether correlation coefficient auxiliary judgment Transformer Winding deforms. Utilizing correlation coefficient process to need whole measurement data is carried out computing, and these measurement data have measurement data greatly there is no large effect for measurement result, if whole measurement data being carried out computing, adding the complexity of computing.

As can be seen here, the workload of operation how reduced when analyzing deformation of transformer winding is those skilled in the art's problem demanding prompt solutions.

Summary of the invention

It is an object of the invention to provide the decision method of a kind of deformation of transformer winding, the accuracy that the requirement of data mode, raising winding deformation are judged by workload of operation during for making full use of measurement data, reducing analysis deformation of transformer winding, reduction deformation of transformer winding decision method.

For solving above-mentioned technical problem, the present invention provides the decision method of a kind of deformation of transformer winding, including:

S1: within the scope of predeterminated frequency, obtains described Transformer Winding present impedance frequency sweep curve and original impedance frequency sweep curve;

S2: respectively measure current measurement data a little according to described present impedance frequency sweep curve acquisition;

S3: judge whether described measurement point is extreme point according to described current measurement data;

S4: concentrate if it is, described extreme point to be stored in extreme point;

S5: concentrate at described extreme point, it may be judged whether there is continuous print extreme point;

If there is continuous print extreme point, entering S6, if there is no continuous print extreme point, then entering S8;

S6: concentrate at described extreme point and reject described continuous print extreme point;

S7: the measurement data in described disallowable extreme point frequency range is smoothed; Return S3;

S8: the extreme point concentrated according to described extreme point is analyzed judging the degree of deformation of transformer winding.

Preferably, described S8 specifically includes:

Obtain each extreme point raw measurement data in described original impedance frequency sweep curve that described extreme point is concentrated;

The frequency shift (FS) rate corresponding with described current measurement data according to described raw measurement data and resistance shift rate calculate the deviation ratio of extreme point;

Deviation ratio according to described extreme point and deformation of transformer winding judging rules judge the degree of described deformation of transformer winding.

Preferably, described frequency shift (FS) rate is calculated by equation below:

$\mathrm{\Δ}f=\frac{|f_f-f_o|}{f_o}\×100\%;$

Wherein, f_fFor this extreme point frequency values in described raw measurement data, f_oFor this extreme point frequency values in described current measurement data;

Described resistance shift rate is calculated by equation below:

$\mathrm{\Δ}z=\frac{|z_f-z_o|}{z_o}\×100\%;$

Wherein, z_fFor this extreme point resistance value in described raw measurement data, z_oFor this extreme point resistance value in described current measurement data;

The deviation ratio of described extreme point is calculated by equation below:

$\mathrm{\Δ}p=\sqrt{{\left(\mathrm{\Δ}z\right)}^2+{\left(\mathrm{\Δ}f\right)}^2}.$

Preferably, the described deviation ratio according to described extreme point and deformation of transformer winding judging rules obtain the degree of described deformation of transformer winding and specifically include:

Maximum extreme point deviation rate �� p is obtained within the scope of first frequency_L;

Maximum extreme point deviation rate �� p is obtained within the scope of second frequency_H;

The degree of described deformation of transformer winding is obtained according to described deformation of transformer winding judging rules;

Wherein, as �� p_L>=0.4 or �� p_H>=0.3 is the first degree deformation;

As 0.2�ܦ� p_L< 0.4 or 0.1�ܦ� p_HThe quantity of the extreme point in the quantity of the extreme point on < 0.3 or described present impedance frequency sweep curve and described original impedance frequency sweep curve is not all the second degree deformation;

As �� p_L< 0.2 and �� p_HThe quantity of the extreme point on < 0.1 and described present impedance frequency sweep curve and the quantity of the extreme point on described original impedance frequency sweep curve are all the 3rd degree deformation mutually.

Preferably, described first frequency ranges for 10Hz-100kHZ; Described second frequency ranges for 100kHz 200kHz.

Preferably, described S3 specifically includes:

If the current measurement data measuring point is all higher than or is respectively less than the current measurement data measuring point being adjacent, then this measurement point is extreme point;

Wherein, if the current measurement data measuring point is all higher than the current measurement data measuring point being adjacent, then this measurement point is maximum point;

If the current measurement data measuring point is respectively less than the current measurement data measuring point being adjacent, then this measurement point is minimum point.

Preferably, described S7 specifically includes:

The measurement data of described disallowable extreme point is carried out single order medium filtering process.

The decision method of deformation of transformer winding provided by the present invention, after obtain each current measurement data measuring point according to present impedance frequency sweep curve, judge to measure whether point is extreme point according to current measurement data, then the measurement point being extreme point is stored in extreme point and concentrates. Concentrate at extreme point and determine whether continuous print extreme point, if had, then reject these extreme points, then the measurement data that remaining extreme point is corresponding is smoothed, then proceed to judge whether remaining measurement point remains as extreme point, repetitive cycling above-mentioned steps, until the extreme point that extreme point is concentrated is all discontinuous, the extreme point finally extreme point concentrated is analyzed obtaining the degree of deformation of transformer winding. Due to, in above process, the measurement point not being extreme point is not paid attention to, it is to avoid the process of invalid data, reduce the workload of calculating process, improve work efficiency.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention, the accompanying drawing used required in embodiment will be done simple introduction below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the premise not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the flow chart of the decision method of a kind of deformation of transformer winding provided by the invention;

Fig. 2 is the comparison diagram of original impedance frequency sweep curve provided by the invention and present impedance frequency sweep curve;

Fig. 3 is the schematic diagram of deformation of transformer winding degree provided by the invention.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is only a part of embodiment of the present invention, rather than whole embodiment. Based on the embodiment in the present invention, those of ordinary skill in the art under not making creative work premise, the every other embodiment obtained, broadly fall into scope.

The core of the present invention is to provide the decision method of a kind of deformation of transformer winding.

In order to make those skilled in the art be more fully understood that the present invention program, below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.

Fig. 1 is the flow chart of the decision method of a kind of deformation of transformer winding provided by the invention. As it is shown in figure 1, the decision method of deformation of transformer winding, including:

S1: within the scope of predeterminated frequency, obtains Transformer Winding present impedance frequency sweep curve and original impedance frequency sweep curve;

S2: respectively measure current measurement data a little according to present impedance frequency sweep curve acquisition;

S3: judge to measure whether point is extreme point according to current measurement data;

S4: concentrate if it is, extreme point to be stored in extreme point;

S5: concentrate at extreme point, it may be judged whether there is continuous print extreme point;

If there is continuous print extreme point, entering S6, if there is no continuous print extreme point, then entering S8;

S6: concentrate at extreme point and reject continuous print extreme point;

S7: the measurement data in described disallowable extreme point frequency range is smoothed; Return S3;

S8: be analyzed judging the degree of deformation of transformer winding according to the extreme point that extreme point is concentrated.

In being embodied as, before Transformer Winding is not deformed, we need to obtain its original impedance frequency sweep curve and Transformer Winding present impedance frequency sweep curve, can obtain each current measurement data measuring point by present impedance frequency sweep curve. Having a lot owing to measuring point, and have measurement point greatly little for the impact of follow-up analysis process, if whole measurement points is all carried out subsequent analysis, then workload is very big. The present embodiment have chosen extreme point as the object analyzed in whole measuring in point. Point is measured for each, it would be desirable to be analyzed whether it is extreme point. If there being 100 points, then filter out whole extreme points in 100 points. The measurement point that these are extreme points is stored in extreme point concentrate, for instance measure in point for 100 and have 20 extreme points, then extreme value point set just includes 20 and measures point. In these extreme points, it is possible to there will be two continuous print extreme points (measuring point is continuous print, for instance the 5th is measured point with the 6th measurement is all extreme point). In the event of two continuous print extreme points, then need to concentrate at extreme point to reject this part continuous print extreme point, then the measurement data in disallowable extreme point frequency range is smoothed, after having processed, rejudge whether the measurement point in disallowable extreme point frequency range is extreme point, if it is it is stored in extreme point to concentrate, then proceed to judge extreme point concentrates whether there is continuous print extreme point, until extreme point concentrates whole measurement points to be all extreme point, and there is no continuous print extreme point. It is analyzed obtaining the degree of deformation of transformer winding according to the extreme point that final extreme point is concentrated.

Wherein, step S8 specifically includes:

The each extreme point that acquisition extreme point is concentrated raw measurement data in original impedance frequency sweep curve;

The frequency shift (FS) rate corresponding with current measurement data according to raw measurement data and resistance shift rate calculate the deviation ratio of extreme point;

Deviation ratio according to extreme point and deformation of transformer winding judging rules obtain the degree of deformation of transformer winding.

Fig. 2 is the comparison diagram of original impedance frequency sweep curve provided by the invention and present impedance frequency sweep curve. Obtain original impedance frequency sweep curve and present impedance frequency sweep curve in the above-described embodiments, in this embodiment, by corresponding for each extreme point in original impedance frequency sweep curve, find the raw measurement data that these extreme points are corresponding. For each extreme point, find raw measurement data and current measurement data, obtain frequency shift (FS) rate and resistance shift rate, calculated the deviation ratio of each extreme point by frequency shift (FS) rate and resistance shift rate. Concrete, for any one extreme point, its frequency shift (FS) rate is calculated by equation below:

$\mathrm{\&Delta;}f=\frac{|f_f-f_o|}{f_o}\&times;100\%;$

Wherein, f_fFor this extreme point frequency values in raw measurement data, f_oFor this extreme point frequency values in current measurement data;

Resistance shift rate is calculated by equation below:

$\mathrm{\&Delta;}z=\frac{|z_f-z_o|}{z_o}\&times;100\%;$

Wherein, z_fFor this extreme point resistance value in raw measurement data, z_oFor this extreme point resistance value in current measurement data;

The deviation ratio of extreme point is calculated by equation below:

$\mathrm{\&Delta;}p=\sqrt{{\left(\mathrm{\&Delta;}z\right)}^2+{\left(\mathrm{\&Delta;}f\right)}^2}.$

The deviation ratio of each extreme point is just calculated by above-mentioned formula. The degree of deformation of transformer winding just can be analyzed by the deviation ratio of extreme point. In the present invention, the degree of deformation of transformer winding is judged particular by following judging rules.

Within the scope of first frequency, for instance first frequency ranges for 10Hz-100kHz, obtain maximum extreme point deviation rate �� p_L; Within the scope of second frequency, for instance second frequency ranges for 100kHz 200kHz and obtains maximum extreme point deviation rate �� p_H��

If �� p_L>=0.4 or �� p_H>=0.3 is the first degree deformation, it is believed that deformation of transformer winding is very serious, now the quantity of the quantity with the extreme point on original impedance frequency sweep curve without comparing the extreme point on present impedance frequency sweep curve;

If4 or 0.1�ܦ� p_HThe quantity of the extreme point in the quantity of the extreme point on < 0.3 or present impedance frequency sweep curve and original impedance frequency sweep curve is not all the second degree deformation, it is believed that deformation of transformer winding ratio is more serious;

If �� p_L< 0.2 and �� p_HThe quantity of the extreme point on < 0.1 and present impedance frequency sweep curve and the quantity of the extreme point on original impedance frequency sweep curve are all the 3rd degree deformation mutually, it is believed that Transformer Winding is substantially free of deformation.

Fig. 3 is the schematic diagram of deformation of transformer winding degree provided by the invention.

The present invention judge one measure point be whether extreme point according to being:

If the current measurement data measuring point is all higher than or is respectively less than the current measurement data measuring point being adjacent, then this measurement point is extreme point;

Wherein, if the current measurement data measuring point is all higher than the current measurement data measuring point being adjacent, then this measurement point is maximum point;

If the current measurement data measuring point is respectively less than the current measurement data measuring point being adjacent, then this measurement point is minimum point.

Wherein, the measurement data of described disallowable extreme point is specifically carried out single order medium filtering process by smoothing processing in the above-described embodiments.

The decision method of the deformation of transformer winding that above-described embodiment provides, after obtain each current measurement data measuring point according to present impedance frequency sweep curve, judge to measure whether point is extreme point according to current measurement data, then the measurement point being extreme point is stored in extreme point and concentrates. Concentrate at extreme point and determine whether continuous print extreme point, if had, then reject these extreme points, then the measurement data that remaining extreme point is corresponding is smoothed, then proceed to judge whether remaining measurement point remains as extreme point, repetitive cycling above-mentioned steps, until the extreme point that extreme point is concentrated is all discontinuous, the extreme point finally extreme point concentrated is analyzed obtaining the degree of deformation of transformer winding. Due to, in above process, the measurement point not being extreme point is not paid attention to, it is to avoid the process of invalid data, reduce the workload of calculating process, improve work efficiency.

Above the decision method of deformation of transformer winding provided by the present invention is described in detail. In description, each embodiment adopts the mode gone forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar portion mutually referring to. For device disclosed in embodiment, owing to it corresponds to the method disclosed in Example, so what describe is fairly simple, relevant part illustrates referring to method part. It should be pointed out that, for those skilled in the art, under the premise without departing from the principles of the invention, it is also possible to the present invention carries out some improvement and modification, these improve and modify in the protection domain also falling into the claims in the present invention.

Professional further appreciates that, the unit of each example described in conjunction with the embodiments described herein and algorithm steps, can with electronic hardware, computer software or the two be implemented in combination in, in order to clearly demonstrate the interchangeability of hardware and software, generally describe composition and the step of each example in the above description according to function. These functions perform with hardware or software mode actually, depend on application-specific and the design constraint of technical scheme. Professional and technical personnel specifically can should be used for using different methods to realize described function to each, but this realization is it is not considered that beyond the scope of this invention.

The method described in conjunction with the embodiments described herein or the step of algorithm can directly use the software module that hardware, processor perform, or the combination of the two is implemented. Software module can be placed in any other form of storage medium known in random access memory (RAM), internal memory, read only memory (ROM), electrically programmable ROM, electrically erasable ROM, depositor, hard disk, moveable magnetic disc, CD-ROM or technical field.

Claims (7)

1. the decision method of a deformation of transformer winding, it is characterised in that including:

S1: within the scope of predeterminated frequency, obtains described Transformer Winding present impedance frequency sweep curve and original impedance frequency sweep curve;

S2: respectively measure current measurement data a little according to described present impedance frequency sweep curve acquisition;

S3: judge whether described measurement point is extreme point according to described current measurement data;

S4: concentrate if it is, described extreme point to be stored in extreme point;

S5: concentrate at described extreme point, it may be judged whether there is continuous print extreme point;

If there is continuous print extreme point, entering S6, if there is no continuous print extreme point, then entering S8;

S6: concentrate at described extreme point and reject described continuous print extreme point;

S7: the measurement data in described disallowable extreme point frequency range is smoothed; Return S3;

S8: the extreme point concentrated according to described extreme point is analyzed judging the degree of deformation of transformer winding.

2. the decision method of deformation of transformer winding according to claim 1, it is characterised in that described S8 specifically includes:

Obtain each extreme point raw measurement data in described original impedance frequency sweep curve that described extreme point is concentrated;

The frequency shift (FS) rate corresponding with described current measurement data according to described raw measurement data and resistance shift rate calculate the deviation ratio of extreme point;

Deviation ratio according to described extreme point and deformation of transformer winding judging rules judge the degree of described deformation of transformer winding.

3. the decision method of deformation of transformer winding according to claim 2, it is characterised in that described frequency shift (FS) rate is calculated by equation below:

$\mathrm{\&Delta;}f=\frac{\left|f_f-f_o\right|}{f_o}\&times;100\%;$

Wherein, f_fFor this extreme point frequency values in described raw measurement data, f_oFor this extreme point frequency values in described current measurement data;

Described resistance shift rate is calculated by equation below:

$\mathrm{\&Delta;}z=\frac{\left|z_f-z_o\right|}{z_o}\&times;100\%;$

Wherein, z_fFor this extreme point resistance value in described raw measurement data, z_oFor this extreme point resistance value in described current measurement data;

The deviation ratio of described extreme point is calculated by equation below:

$\mathrm{\&Delta;}p=\sqrt{{\left(\mathrm{\&Delta;}z\right)}^2+{\left(\mathrm{\&Delta;}f\right)}^2}.$

4. the decision method of deformation of transformer winding according to claim 3, it is characterised in that the described deviation ratio according to described extreme point and deformation of transformer winding judging rules obtain the degree of described deformation of transformer winding and specifically include:

Maximum extreme point deviation rate �� p is obtained within the scope of first frequency_L;

Maximum extreme point deviation rate �� p is obtained within the scope of second frequency_H;

The degree of described deformation of transformer winding is obtained according to described deformation of transformer winding judging rules;

Wherein, as �� p_L>=0.4 or �� p_H>=0.3 is the first degree deformation;

As 0.2�ܦ� p_L< 0.4 or 0.1�ܦ� p_HThe quantity of the extreme point in the quantity of the extreme point on < 0.3 or described present impedance frequency sweep curve and described original impedance frequency sweep curve is not all the second degree deformation;

As �� p_L< 0.2 and �� p_HThe quantity of the extreme point on < 0.1 and described present impedance frequency sweep curve and the quantity of the extreme point on described original impedance frequency sweep curve are all the 3rd degree deformation mutually.

5. the decision method of deformation of transformer winding according to claim 4, it is characterised in that described first frequency ranges for 10Hz-100kHz; Described second frequency ranges for 100kHz-200kHz.

6. the decision method of deformation of transformer winding according to claim 1, it is characterised in that described S3 specifically includes:

If the current measurement data measuring point is all higher than or is respectively less than the current measurement data measuring point being adjacent, then this measurement point is extreme point;

Wherein, if the current measurement data measuring point is all higher than the current measurement data measuring point being adjacent, then this measurement point is maximum point;

If the current measurement data measuring point is respectively less than the current measurement data measuring point being adjacent, then this measurement point is minimum point.

7. the decision method of deformation of transformer winding according to claim 1, it is characterised in that described S7 specifically includes:

The measurement data of described disallowable extreme point is carried out single order medium filtering process.