CN108169760B - high-voltage circuit breaker low-frequency swing measuring method - Google Patents
high-voltage circuit breaker low-frequency swing measuring method Download PDFInfo
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- CN108169760B CN108169760B CN201711380467.3A CN201711380467A CN108169760B CN 108169760 B CN108169760 B CN 108169760B CN 201711380467 A CN201711380467 A CN 201711380467A CN 108169760 B CN108169760 B CN 108169760B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/46—Indirect determination of position data
- G01S17/48—Active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves
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Abstract
The invention discloses a high-voltage circuit breaker low-frequency swing measuring method which comprises the steps of arranging two laser ranging sensors around a high-voltage circuit breaker, measuring the distance of a position to be measured on the high-voltage circuit breaker by the laser ranging sensors at fixed frequency, calculating the swing track of the position to be measured in the projection direction of the connecting line of the laser ranging sensors and the position to be measured on a horizontal plane according to the distance and the included angle between the connecting line of the laser ranging sensors and the position to be measured and the horizontal direction, decomposing the swing tracks in the two directions into two directions which are perpendicular to each other respectively, and combining the two directions to calculate the complete swing track of the position to be measured.
Description
Technical Field
The invention relates to a low-frequency swing measuring method of a high-voltage circuit breaker in an ultrahigh-voltage transmission power transformation system.
Background
In the ultrahigh voltage power transmission and transformation system, the top end of a high-voltage circuit breaker is provided with high voltage up to 750 kilovolts, the swing amplitude of the high-voltage circuit breaker is the largest, the lower end of the high-voltage circuit breaker is provided with an end, the potential of 0 volt is constrained by a base, the swing amplitude is the smallest, and the force is not small; the top end of the high-voltage circuit breaker is provided with ultrahigh voltage, the whole circuit breaker sleeve is hollow, is made of insulating materials and is rigid, the whole circuit breaker sleeve is not allowed to be approached from the safety angle, and a sensor cannot be directly installed to measure the swing condition of the circuit breaker sleeve, so that an effective method for measuring the low-frequency swing of the top end of the high-voltage circuit breaker is not available.
The above background disclosure is only for the purpose of assisting understanding of the concept and technical solution of the present invention and does not necessarily belong to the prior art of the present patent application, and should not be used for evaluating the novelty and inventive step of the present application in the case that there is no clear evidence that the above content is disclosed at the filing date of the present patent application.
Disclosure of Invention
In order to solve the technical problems, the invention provides high-voltage circuit breaker low-frequency swing measuring methods, and the low-frequency swing track of the high-voltage circuit breaker is measured in a non-contact remote mode.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention discloses a high-voltage circuit breaker low-frequency swing measuring method, which comprises the following steps:
s1, mounting a th laser ranging sensor at a position with a preset distance from the th position of the high-voltage circuit breaker, and mounting a second laser ranging sensor at a position with a second preset distance from the high-voltage circuit breaker;
s2, the laser ranging sensor measures the distance from the position to be measured on the high-voltage circuit breaker at a th frequency, and calculates the swing track of the position to be measured in a th direction according to the measured distance between the laser ranging sensor and the position to be measured and the th included angle between the connecting line of the laser ranging sensor and the position to be measured and the horizontal direction, wherein the direction is the projection direction of the connecting line of the laser ranging sensor and the position to be measured on the horizontal plane;
s3, the second laser ranging sensor measures the distance from the position to be measured at a second frequency, and calculates and obtains the swing track of the position to be measured in a second direction according to the measured distance between the second laser ranging sensor and the position to be measured and a second included angle between the connecting line of the second laser ranging sensor and the position to be measured and the horizontal direction, wherein the second direction is the projection direction of the connecting line of the second laser ranging sensor and the position to be measured on the horizontal plane, a preset included angle is arranged between the second direction and the direction, and the preset included angle is larger than 0 degree and smaller than 180 degrees;
and S4, decomposing the swing tracks of the position to be detected in the th direction and the second direction into two directions which are perpendicular to each other respectively, and then combining and calculating to obtain the complete swing track of the position to be detected.
Preferably, the th preset distance is 10-20 m, and the second preset distance is 10-20 m.
Preferably, the th predetermined distance is equal to the second predetermined distance.
Preferably, the th direction is perpendicular to the second direction.
Preferably, the th angle is equal to the second angle.
Preferably, the th laser ranging sensor and the second laser ranging sensor are both installed on a horizontal plane where the bottom end of the high-voltage circuit breaker is located.
Preferably, the th frequency and the second frequency are equal.
Preferably, the th frequency and the second frequency are respectively 1-10 Hz.
Preferably, an elevation angle measuring module is respectively arranged on the th laser ranging sensor and the second laser ranging sensor.
Preferably, the method for measuring the low-frequency swing of the high-voltage circuit breaker further comprises the following steps:
and S5, respectively installing a contact type sensor and a second contact type sensor in two mutually perpendicular directions on the bottom end of the high-voltage circuit breaker, and then obtaining a complete swing track of the bottom end of the high-voltage circuit breaker according to swing tracks obtained by respectively measuring the contact type sensor and the second contact type sensor.
Compared with the prior art, the method has the advantages that the two laser ranging sensors are arranged around the high-voltage circuit breaker, the distance from the position to be measured on the high-voltage circuit breaker is measured by the laser ranging sensors at fixed frequency, the swing track of the position to be measured in the projection direction of the connecting line of the laser sensor and the position to be measured on the horizontal plane can be obtained through calculation according to the distance and the included angle between the connecting line of the laser ranging sensors and the position to be measured and the horizontal direction, the two swing tracks with the preset included angle are combined and can be respectively decomposed to the two directions which are perpendicular to each other, the complete swing track of the position to be measured can be obtained through combination calculation, and the complete swing track of any positions to be measured on the high-voltage circuit breaker can be measured by the measuring method without contacting the top end of the high-.
In the scheme of the step , the direction and the second direction of the two laser ranging sensors are perpendicular to each other, so that the swing track of the position to be measured in the direction and the swing track of the position to be measured in the second direction can be directly combined and calculated in the step S4 to obtain a complete swing track of the position to be measured, the step is simplified, and the step is further performed, wherein the frequencies measured by the two laser ranging sensors are the same and are both 1-10 Hz, and the method is suitable for natural wind frequency, so that the measurement data volume of the laser ranging sensors is smaller on the basis of accurately measuring the swing track, and the calculated amount is not large.
Drawings
Fig. 1 is a schematic flow diagram of a low frequency swing measurement method for a high voltage circuit breaker according to a preferred embodiment of the present invention;
FIG. 2 is a schematic view of a th laser ranging sensor measuring in accordance with an embodiment of the present invention;
FIG. 3 is a dimensional schematic of the measurements in FIG. 2;
FIG. 4 is a schematic projection view of the wobble measurement of FIG. 2;
FIG. 5 is a schematic view of a computational analysis of the measurements in FIG. 2;
FIG. 6 is a schematic illustration of the installation of th laser ranging sensor and a second laser ranging sensor in accordance with an embodiment of the present invention;
fig. 7 is a schematic diagram of the swing locus of the low frequency swing of the high voltage circuit breaker measured according to the embodiment of the present invention;
fig. 8 is a schematic view of a structure for measuring the bottom end of a high voltage circuit breaker according to an embodiment of the present invention.
Detailed Description
The invention will now be described in further detail with reference to the drawings and preferred embodiments.
As shown in fig. 1, the method for measuring low frequency swing of a high voltage circuit breaker according to a preferred embodiment of the present invention includes the following steps:
s1, mounting a th laser ranging sensor at a position with a preset distance from the th position of the high-voltage circuit breaker, and mounting a second laser ranging sensor at a position with a second preset distance from the high-voltage circuit breaker;
s2, the laser ranging sensor measures the distance from the position to be measured on the high-voltage circuit breaker at the th frequency, and calculates and obtains the swing track of the position to be measured in the th direction according to the measured distance between the laser ranging sensor and the position to be measured and the th included angle between the connecting line of the laser ranging sensor and the position to be measured and the horizontal direction, wherein the direction is the projection direction of the connecting line of the laser ranging sensor and the position to be measured on the horizontal plane;
s3, the second laser ranging sensor measures the distance from the position to be measured at a second frequency, and calculates and obtains the swing track of the position to be measured in a second direction according to the measured distance between the second laser ranging sensor and the position to be measured and a second included angle between the connecting line of the second laser ranging sensor and the position to be measured and the horizontal direction, wherein the second direction is the projection direction of the connecting line of the second laser ranging sensor and the position to be measured on the horizontal plane, a preset included angle is arranged between the second direction and the direction, and the preset included angle is larger than 0 degree and smaller than 180 degrees;
s4, decomposing the swing tracks of the position to be detected in the th direction and the second direction into two directions which are perpendicular to each other, and combining and calculating to obtain a complete swing track of the position to be detected;
and S5, respectively installing a contact type sensor and a second contact type sensor in two mutually perpendicular directions on the bottom end of the high-voltage circuit breaker, and then obtaining a complete swing track of the bottom end of the high-voltage circuit breaker according to swing tracks respectively obtained by measuring the contact type sensor and the second contact type sensor.
In the step embodiment, the predetermined distance is 10-20 m, the second predetermined distance is 10-20 m, wherein the 0 predetermined distance may be equal to the second predetermined distance, the step is that the direction is perpendicular to the second direction, the included angle is equal to the second included angle, that is, the laser ranging sensor and the second laser ranging sensor may be installed on the same horizontal plane, preferably, both the laser ranging sensor and the second laser ranging sensor are installed on the horizontal plane where the bottom end of the high voltage circuit breaker is located, in the embodiment, the frequency and the second frequency are equal and are 1-10 Hz respectively.
The principle of using a non-contact remote measurement method to measure the swing track of a position to be measured on a high-voltage circuit breaker in the present application is described below by taking an th laser ranging sensor as an example.
The -th laser ranging sensor 200 is fixed at a point, the distance measurement is carried out on the fixed position of the high-voltage circuit breaker 100 at fixed angles (the -th included angle), the high-voltage circuit breaker 100 swings in natural wind, the -th laser ranging sensor 200 is used for continuously measuring the distance in the same fixed direction, different distances can be output, different distances are output relative to the fixed -th laser ranging sensor 200, namely the swing of the high-voltage circuit breaker 100, as shown in fig. 2, a sphere 10 represents the position where the high-voltage circuit breaker 100 is relatively static under breeze, spheres 20 and 30 respectively represent the positions where the high-voltage circuit breaker 100 swings under natural wind, and points B, A and C respectively represent the position points of the high-voltage circuit breaker 100 on the light path 201 of the -th laser ranging sensor 200.
With reference to fig. 3, in which the swing of the high voltage circuit breaker 100 surrounds the fixed end position thereof, and the distance between the measuring point of the th laser ranging sensor 200 and the fixed end position 101 (bottom end) of the high voltage circuit breaker 100 does not change, taking the example that the th laser ranging sensor 200 is disposed on the horizontal plane where the fixed end position 101 (bottom end) of the high voltage circuit breaker 100 is located, the projection of the swing track of the high voltage circuit breaker 100 perpendicular to the horizontal plane (ground) also changes within fixed ranges, and the swing track of the th laser ranging sensor 200 and the plane where the high voltage circuit breaker 100 is located in the projection direction of the horizontal plane can be obtained through the following calculation through the measurement of the th laser ranging sensor 200.
As shown in fig. 3, Δ d ═ d-d1Or Δ d ═ d2-d is the variation range of the high voltage circuit breaker 100 swing on the optical path 201; Δ r ═ r-r1Or Δ r ═ r2R is the variation range of the swing locus of the high-voltage circuit breaker 100 projected on the horizontal plane (ground) on the optical path, wherein, as can be seen from the figure, r is d cos α. the swing locus of the high-voltage circuit breaker 100 needs to be measured, what needs to be described is the projection of the swing locus of the high-voltage circuit breaker 100 on the horizontal plane (ground), as shown in fig. 4, the blocks 40 and 50 respectively represent the horizontal values of the high-voltage circuit breaker projected on the horizontal plane (ground).
Under the premise of distance measurement and unchanged elevation angle under the same light path, the height h of the high-voltage circuit breaker 100 vertical to the ground is1、h、h2The calculation is not affected, namely the height perpendicular to the ground on the high-voltage circuit breaker 100 on the same optical path is not affected, wherein an elevation angle dynamic measurement module is arranged on the laser ranging sensor 200, and the elevation angle of the laser ranging sensor 200 is set to be kept unchanged in each measurement process, namely, the measurement result is not affected.
Due to the existence of the elevation angle in the measurement process, the projection of the swing track of the high-voltage circuit breaker 100 to be described on the vertical ground is influenced, as shown in fig. 5, the projection of the swing track of the high-voltage circuit breaker is directly described by adopting a formula Δ r ═ Δ d ═ cos α, and a right triangle b is obtained1A, and for high voltage disconnection on the same light pathThe swing locus of the device 100 is described by the projection of the same height (i.e. the fixed position of the high-voltage circuit breaker 100, i.e. the position to be measured) on the horizontal plane (ground), and as can be seen from fig. 5, the triangle b1A is similar triangle, and for the same measurement of light paths at the same time, the triangle b in the same measurement needs to be measured1A is scaled up to triangle a1And the measured values in the a direction (swinging towards the th laser ranging sensor 200 direction) are amplified in equal proportion, wherein the amplification proportion is
Where h is the height of the position of the light spot in the stationary state of the high voltage circuit breaker 100.
According to the calculation, the swing track of the position to be measured of the high-voltage circuit breaker 100 on the plane shared by the laser ranging sensor 200 and the high-voltage circuit breaker 100 can be calculated, through repeating the measurement and calculation processes, the swing track of the position to be measured of the high-voltage circuit breaker 100 on the plane shared by the second laser ranging sensor 300 and the high-voltage circuit breaker 100 can be measured through the second laser ranging sensor 300, then the swing tracks of the swing tracks and the swing tracks of the swing tracks are respectively decomposed in the x-axis direction and the y-axis direction (two directions perpendicular to each other), and combined calculation is carried out, so that the complete swing track of the position to be measured of the high-voltage circuit breaker is obtained.
As shown in FIG. 8, an -th contact sensor 400 and a second contact sensor 500 are respectively installed in two vertical directions at the bottom end of the high voltage circuit breaker 100, acceleration (force), speed and displacement data in corresponding directions can be respectively measured by the -th contact sensor 400 and the second contact sensor 500, a waveform and a frequency are obtained in , a swing track in the corresponding direction is obtained, and a complete swing track of the bottom end of the high voltage circuit breaker 100 is obtained according to the swing tracks obtained by the two measurements.
By the measuring method, the low-frequency swing track of the high-voltage circuit breaker is measured in a non-contact remote mode, and the measuring safety is guaranteed.
It will be apparent to those skilled in the art that many equivalent substitutions or obvious modifications, all of which are intended to be encompassed by the present invention, whether identical in performance or use, are possible without departing from the spirit of the invention.
Claims (9)
1, A low-frequency swing measuring method of a high-voltage circuit breaker, which is characterized by comprising the following steps:
s1, installing a th laser ranging sensor at a position which is a preset distance away from the th position of the high-voltage circuit breaker, installing a second laser ranging sensor at a position which is a second preset distance away from the high-voltage circuit breaker, and installing both the th laser ranging sensor and the second laser ranging sensor on a horizontal plane where the bottom end of the high-voltage circuit breaker is located;
s2, the laser ranging sensor measures the distance from the position to be measured on the high-voltage circuit breaker at a th frequency, and calculates the swing track of the position to be measured in a th direction according to the measured distance between the laser ranging sensor and the position to be measured and the th included angle between the connecting line of the laser ranging sensor and the position to be measured and the horizontal direction, wherein the direction is the projection direction of the connecting line of the laser ranging sensor and the position to be measured on the horizontal plane;
s3, the second laser ranging sensor measures the distance from the position to be measured at a second frequency, and calculates and obtains the swing track of the position to be measured in a second direction according to the measured distance between the second laser ranging sensor and the position to be measured and a second included angle between the connecting line of the second laser ranging sensor and the position to be measured and the horizontal direction, wherein the second direction is the projection direction of the connecting line of the second laser ranging sensor and the position to be measured on the horizontal plane, a preset included angle is arranged between the second direction and the direction, and the preset included angle is larger than 0 degree and smaller than 180 degrees;
and S4, decomposing the swing tracks of the position to be detected in the th direction and the second direction into two directions which are perpendicular to each other respectively, and then combining and calculating to obtain the complete swing track of the position to be detected.
2. The method for measuring the low frequency swing of the high voltage circuit breaker according to claim 1, wherein the -th predetermined distance is 10-20 m, and the second predetermined distance is 10-20 m.
3. The high voltage circuit breaker low frequency swing measurement method of claim 1, wherein said th predetermined distance is equal to said second predetermined distance.
4. The method of claim 1, wherein the th direction and the second direction are perpendicular to each other.
5. The method for measuring low frequency swing of a high voltage circuit breaker according to claim 1, wherein said th angle is equal to said second angle.
6. The method of claim 1, wherein the frequency and the second frequency are equal.
7. The method for measuring the low-frequency swing of the high-voltage circuit breaker according to claim 6, wherein the th frequency and the second frequency are respectively 1-10 Hz.
8. The method for measuring the low-frequency swing of the high-voltage circuit breaker according to claim 1, wherein an elevation angle measuring module is respectively arranged on the th laser ranging sensor and the second laser ranging sensor.
9. The method of measuring low frequency swing of a high voltage circuit breaker of any of claims 1-8, further comprising the steps of:
and S5, respectively installing a contact type sensor and a second contact type sensor in two mutually perpendicular directions on the bottom end of the high-voltage circuit breaker, and then obtaining a complete swing track of the bottom end of the high-voltage circuit breaker according to swing tracks obtained by respectively measuring the contact type sensor and the second contact type sensor.
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| CN104697768A (en) * | 2014-12-23 | 2015-06-10 | 华北电力大学（保定） | Method for testing movement characteristics of dynamic contact of high-voltage circuit breaker |
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| JP2011053025A (en) * | 2009-08-31 | 2011-03-17 | Nissan Motor Co Ltd | Distance measuring device and method of measuring distance |
| CN104697768A (en) * | 2014-12-23 | 2015-06-10 | 华北电力大学（保定） | Method for testing movement characteristics of dynamic contact of high-voltage circuit breaker |
| CN106650551A (en) * | 2015-10-30 | 2017-05-10 | 国网山西省电力公司电力科学研究院 | High-voltage breaker moving contact movement track real-time identification method based on priori knowledge |
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