CN113866505B - Grounding grid on-resistance measurement and grounding grid state evaluation method and system - Google Patents
Grounding grid on-resistance measurement and grounding grid state evaluation method and system Download PDFInfo
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- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/08—Measuring resistance by measuring both voltage and current
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- G—PHYSICS
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Abstract
The invention provides a method and a system for measuring the on-resistance of a grounding grid and evaluating the state of the grounding grid, comprising the following steps: selecting a grounding down-lead as a measuring point and a datum point; the metal surface of the exposed grounding down conductor is respectively connected with a current pole and a voltage pole for conducting a power supply; a constant direct current test current is led in between the current pole of the datum point and the current pole of the measuring point; analyzing the materials used by the grounding down conductor, calculating the cross section area of the grounding down conductor, and calculating the ideal value and the actual value of the on-resistance of the grounding grid; and calculating the ratio of the ideal value to the actual value of the on-resistance of the grounding grid, and evaluating the state of the grounding grid according to the ratio. According to the materials and cross sectional areas of different grounding conductors, adopting different on-resistance approximate calculation formulas to calculate the on-resistance ideal values of the grounding network of different materials, and accurately evaluating the state of the grounding network according to the ratio of the ideal value to the actual value of the on-resistance of the grounding network.
Description
Technical Field
The invention relates to the field of power system measurement and evaluation, in particular to a method and a system for measuring on-resistance of a grounding grid and evaluating the state of the grounding grid.
Background
The grounding grid is a horizontal net-shaped grounding device which is buried underground and consists of vertical and horizontal grounding poles, and is an important facility for maintaining the normal operation of the power system. Once the grounding grid is constructed, the grounding grid is buried underground throughout the year, and the grounded metal conductor is in direct contact with soil. As the operational years increase, grounded metal conductors may be subject to varying degrees of corrosion, affecting the integrity of the grounding device, thereby jeopardizing the safe operation of the power system. Therefore, it is necessary to measure the electrical conductivity between various electrical devices and between the parts of the grounding device, ensuring the normal operation of the power system. The electrical conductivity of the ground plane is typically characterized by a dc resistance measurement, and thus measuring the electrical conductivity of the ground plane requires measuring the on-resistance of the ground plane.
The publication No. CN106154047A (publication No. 2016-11-23) provides a method for measuring the grounding resistance of a grounding network, comprising the following steps: setting a measuring loop, a voltage pole and an auxiliary current pole; measuring the distance between the voltage pole and the auxiliary current pole and the potential difference between the voltage pole and the grounding grid; according to the distance and the potential difference, adopting a least square method to obtain the optimal parameter of the analytic function; and calculating the grounding resistance value by using the optimal parameters and the analytic function. The auxiliary current pole potential distribution is measured, an analytical calculation formula of the auxiliary current pole potential is combined, error analysis and parameter selection of a fitting result are carried out by a least square method, an auxiliary current pole actual measurement potential distribution curve is determined, meanwhile, the drop of the auxiliary current pole potential to the potential of the grounding network to be measured is compensated in the measurement curve, an accurate value of the ground network potential rise is obtained, and therefore the grounding resistance is obtained.
However, this method ignores the material of the ground conductor and the cross-sectional area of the ground conductor, and the measured on-resistance of the ground network is inaccurate, and the result of evaluating the state of the ground network using this on-resistance is also inaccurate.
Disclosure of Invention
The invention provides a method and a system for measuring the on-resistance of a grounding grid and evaluating the state of the grounding grid, which are used for overcoming the defects of inaccurate on-resistance measurement result and inaccurate state evaluation result of the grounding grid in the prior art.
In order to solve the technical problems, the technical scheme of the invention is as follows:
the invention provides a method for measuring the on-resistance of a grounding grid and evaluating the state of the grounding grid, which comprises the following steps:
s1: selecting a grounding down-lead as a measuring point of the on-resistance of the grounding grid, selecting the grounding down-lead of the main transformer as a reference point of the measuring point, and respectively connecting the grounding down-lead of the measuring point and the grounding down-lead of the reference point with a current pole and a voltage pole of the on-state power supply;
s2: a constant direct current test current is led in between the current pole of the datum point and the current pole of the measuring point;
s3: measuring and recording the potential difference between the current pole of the datum point and the voltage pole of the measuring point, and measuring the linear distance between the current pole of the datum point and the measuring point on the power station plan;
s4: calculating the actual value of the on-resistance of the grounding grid by utilizing the potential difference between the current pole of the datum point and the voltage pole of the measuring point;
s5: analyzing the materials used by the grounding down conductor, calculating the cross section area of the grounding down conductor, and calculating the ideal value of the on-resistance of the grounding grid according to the materials used by the grounding down conductor, the cross section area and the linear distance between the current pole of the datum point and the measuring point;
s6: calculating the ratio of an ideal value to an actual value of the on-resistance of the grounding grid, and evaluating the state of the grounding grid according to the ratio;
s7: and selecting the next measuring point, and jumping to execute the step S2 until all the measuring points are measured, and ending the measurement.
Preferably, in the step S1, the ground down line selected as the measurement point of the on-resistance of the ground network includes a high voltage device, a low voltage device, a main control ground trunk line, an internal ground trunk line, an independent lightning rod, or a ground down line of the microwave tower. If a plurality of main transformers are arranged, the grounding down-lead closest to the center of the grounding grid is selected as a reference point of the measuring point.
Preferably, the step S2 further comprises defining a first entryThe ground current is I+, and the second ground current is I-; a constant direct current test current is led in between the current pole of the datum point and the current pole of the measuring point, and the first ground current I + And a second earth-entering current I - And (5) setting zero.
Preferably, the steps S3 and S4 further include the following steps, specifically: measuring the composite magnetic induction intensity of the conductor surface of the grounding down conductor between the datum point current pole and the measuring point and the composite magnetic induction intensity of the conductor surface of the steel framework in the power station by using a magnetometer; and if the composite magnetic induction intensity of the conductor surface of the grounding down conductor or the composite magnetic induction intensity of the conductor surface of the steel framework is larger than 0.005Oe, measuring the direct current flowing on the conductor of the grounding down conductor or the conductor of the steel framework by using a flexible coil.
Preferably, when the current direction of the direct current is the direction of the ground, the direct current is added up to the first ground current I + The method comprises the steps of carrying out a first treatment on the surface of the When the current direction of the direct current is the flowing-out ground, the direct current is added up and counted into a second ground current I - 。
Preferably, in the step S4, the calculation formula of the actual value R' of the on-resistance of the ground network is as follows:
wherein V is the potential difference between the current pole of the reference point and the voltage pole of the measurement point.
Preferably, the step S5 specifically includes:
if the grounding down conductor is a copper conductor, the conduction resistance is ideal value R 1 The approximate calculation formula of (a) is:
wherein D is the linear distance between the current pole of the reference point and the measuring point, S is the cross section area of the grounding down conductor;
if the grounding is conducted down conductorThe conductor is a steel conductor, and the conduction resistance is ideal value R 2 The approximate calculation formula of (a) is:
preferably, in the step S6, a calculation formula for calculating a ratio K of an ideal value to an actual value of the on-resistance of the ground network is as follows:
wherein R is i Indicating the ideal on-resistance of the different ground down-lead conductor materials.
Preferably, in the step S6, the evaluating the state of the ground network specifically includes:
when K is less than 2, the grounding grid is in good state;
when K is more than or equal to 2 and less than 5, the grounding grid can still be in a state;
when K is more than or equal to 5 and less than 50, the grounding grid is in a poor state;
when K > 50, the grounding grid is extremely poor.
In a second aspect, the present invention further provides a system for measuring on-resistance of a ground network and evaluating a state of the ground network, which is applied to the method for measuring on-resistance of a ground network and evaluating a state of a ground network provided in any one of the above schemes, and the method includes:
the selection module is used for selecting the grounding down-lead as a measuring point of the on-resistance of the grounding grid, selecting the grounding down-lead of the main transformer as a reference point of the measuring point, and respectively connecting the current pole and the voltage pole of the on-power supply on the grounding down-lead of the selected measuring point and the grounding down-lead of the reference point;
the current lead-in module is used for leading in constant direct current test current between the current pole of the datum point and the current pole of the measuring point;
the measuring module is used for measuring and recording potential difference between the current pole of the datum point and the voltage pole of the measuring point, measuring the linear distance between the current pole of the datum point and the measuring point on the power station plan, and analyzing the material used by the grounding down-lead conductor and measuring the cross section area of the grounding down-lead conductor;
the calculation module is used for calculating the actual on-resistance of the grounding grid by utilizing the potential difference between the current pole of the datum point and the voltage pole of the measuring point; calculating an ideal value of the on-resistance of the grounding grid according to the materials used by the grounding down-lead conductor, the cross-sectional area and the linear distance between the current pole of the datum point and the measuring point; calculating the ratio of an ideal value to an actual value of the on-resistance of the grounding grid;
and the evaluation module is used for evaluating the state of the grounding grid according to the ratio of the ideal value to the actual value of the on-resistance of the grounding grid.
Compared with the prior art, the technical scheme of the invention has the beneficial effects that: the invention establishes an approximate calculation formula of ideal on-resistance based on an approximate theoretical model, calculates the ideal values of the on-resistance of the grounding grid of different materials by adopting different approximate calculation formulas of the on-resistance according to different materials of the grounding conductor and the cross-sectional area of the grounding conductor, and accurately evaluates the state of the grounding grid according to the ratio of the ideal value of the on-resistance of the grounding grid to the actual value.
Drawings
Fig. 1 is a flowchart of a method for measuring on-resistance of a ground network and evaluating the state of the ground network in embodiment 1.
Fig. 2 is a schematic diagram showing the installation of current and voltage poles on the ground down conductor in example 1.
Fig. 3 is a schematic diagram of the system for measuring and evaluating the on-resistance of the grounding grid in embodiment 3.
Wherein, 1-ground down conductor, 2-current pole, 3-voltage pole, 4-ground.
Detailed Description
The drawings are for illustrative purposes only and are not to be construed as limiting the present patent;
for the purpose of better illustrating the embodiments, certain elements of the drawings may be omitted, enlarged or reduced and do not represent the actual product dimensions;
it will be appreciated by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The technical scheme of the invention is further described below with reference to the accompanying drawings and examples.
Example 1
Referring to fig. 1-2, the present embodiment provides a method for measuring on-resistance of a ground network and evaluating a state of the ground network, which specifically includes the following steps:
s1: the grounding down-lead 1 is selected as a measuring point of the on-resistance of the grounding grid, the grounding down-lead 1 of the main transformer is selected as a reference point of the measuring point, and the grounding down-lead 1 of the measuring point and the grounding down-lead 1 of the reference point are respectively connected with a current pole 2 and a voltage pole 3 of the on-state power supply.
In this embodiment, the ground down line 1 selected as the measurement point of the on-resistance of the ground network includes the ground down line 1 of the high voltage device, the low voltage device, the main control ground trunk, the internal ground trunk, the independent lightning rod or the microwave tower. If there are a plurality of main transformers of the ground down-lead 1, the ground down-lead 1 closest to the center of the ground network is selected as the reference point of the measurement point.
In this embodiment, before the grounding down conductor 1 is respectively connected to the current pole 2 and the voltage pole 3 of the power supply, a tool is used to clean the anti-corrosion coating on the metal conductor surface of the grounding down conductor 1, and then the exposed metal conductor surface of the grounding down conductor 1 is respectively connected to the current pole 2 and the voltage pole 3 of the power supply. As shown in fig. 2, fig. 2 is a schematic diagram illustrating the installation of the current electrode 2 and the voltage electrode 3 on the ground down conductor 1 in the present embodiment. In this embodiment, the current electrode 2 is mounted on the ground lead 1 at a height of 0.5m from the ground 4, and the voltage electrode 3 is mounted on the ground lead 1 at a height of 0.3m from the ground 4.
S2: a constant direct current test current is led in between the current pole 2 of the datum point and the current pole 2 of the measuring point; defining a first ground current as I+, and a second ground current as I-; a constant direct current test current is led in between the current pole of the datum point and the current pole of the measuring point, and the first ground current I + And a second earth-entering current I - And (5) setting zero.
In the embodiment, a magnetometer is also used for measuring the composite magnetic induction intensity of the conductor surface of the main grounding down conductor 1 between the datum point current pole 2 and the measuring point and the composite magnetic induction intensity of the conductor surface of the steel framework in the power station; and if the composite magnetic induction intensity of the conductor surface of the grounding lead-down wire 1 or the composite magnetic induction intensity of the conductor surface of the steel framework is larger than 0.005Oe, measuring the direct current flowing on the conductor of the grounding lead-down wire 1 or the steel framework by using a flexible coil. When the current direction of the direct current is the direction of flowing to the ground, the direct current is added up to the first ground current I + The method comprises the steps of carrying out a first treatment on the surface of the When the current direction of the direct current is the flowing-out ground, the direct current is added up and counted into a second ground current I - 。
The steel frame in this embodiment is a member such as a door-shaped frame, a pillar, a bracket, etc. provided in a power station where the ground net is located.
S3: measuring and recording the potential difference between the current pole 2 of the reference point and the voltage pole 3 of the measuring point, and measuring the linear distance between the current pole 2 of the reference point and the measuring point on the power station plan;
s4: the actual value R' of the on-resistance of the grounding network is calculated by using the potential difference between the current electrode 2 of the reference point and the voltage electrode 3 of the measuring point, and the calculation formula is as follows:
where V is the potential difference between the current pole 2 of the reference point and the voltage pole 3 of the measurement point.
S5: analyzing the material used by the conductor of the grounding down-lead 1, calculating the cross-sectional area of the conductor of the grounding down-lead 1, and calculating the ideal value of the on-resistance of the grounding grid according to the material used by the conductor of the grounding down-lead 1, the cross-sectional area and the linear distance between the current pole 2 of the datum point and the measuring point, as follows:
if the conductor of the grounding down conductor 1 is a copper conductor, the conduction resistance is ideal value R 1 The approximate calculation formula of (a) is:
wherein D is the linear distance between the current electrode 2 of the reference point and the measuring point, S is the cross section area of the conductor of the grounding downlead 1;
if the conductor of the grounding down conductor 1 is a steel conductor, the conduction resistance is ideal value R 2 The approximate calculation formula of (a) is:
s6: calculating the ratio of an ideal value to an actual value of the on-resistance of the grounding grid, and evaluating the state of the grounding grid according to the ratio; the calculation formula of the ratio K of the ideal value and the actual value of the on-resistance of the grounding grid is as follows:
wherein R is i Indicating the ideal on-resistance of the different ground down-conductor 1 conductor materials.
S7: the next measuring point is selected, and the step S2 is continued until the measurement is completed.
According to the ground network on-resistance measurement and ground network state evaluation method provided by the embodiment, the shunt of the ground on-network is measured by using the flexible coil in the field actual measurement process, so that the influence of the unknown ground on-network on-resistance measurement value on the ground network is corrected. Based on an approximate theoretical model, an approximate calculation formula of the ideal on-resistance is established, and a ground network state evaluation method according to the ratio K of the ideal value and the actual value of the on-resistance of the ground network is provided. According to different materials of the grounding conductor and the cross sectional area of the grounding conductor, different on-resistance calculation formulas are adopted, so that the on-resistance of the grounding network can be accurately calculated, and the state of the grounding network can be accurately and effectively estimated by utilizing the ratio K of the ideal value and the actual value of the on-resistance of the grounding network.
Example 2
The embodiment provides a method for measuring the on-resistance of a grounding grid and evaluating the state of the grounding grid, wherein when evaluating the state of the grounding grid according to the ratio K of the ideal value to the actual value of the on-resistance of the grounding grid, the evaluating step further comprises:
when the ratio K of the ideal value to the actual value of the on-resistance of the grounding grid is less than 2, the grounding grid is good in state and can maintain normal work;
when K is more than or equal to 2 and less than 5, the state of the grounding grid is still acceptable, the change of the grounding grid is focused, and important equipment is checked and processed when appropriate;
when K is more than or equal to 5 and less than 50, the state of the grounding grid is poor, important equipment is checked as soon as possible, and other equipment is checked at proper time;
when K is more than 50, the state of the grounding grid is extremely poor, the electrical connection performance between the grounding down conductor 1 and the main grid is poor, and the whole equipment should be checked.
Example 3
Referring to fig. 3, the present embodiment provides a system for measuring on-resistance of a ground network and evaluating a state of the ground network, which is applied to the methods for measuring on-resistance of a ground network and evaluating a state of a ground network provided in embodiments 1 and 2, and includes:
the selection module is used for selecting the grounding down lead 1 as a measuring point of the on-resistance of the grounding grid, selecting the grounding down lead 1 of the main transformer as a reference point of the measuring point, and respectively connecting the current pole 2 and the voltage pole 3 of the on-power supply to the grounding down lead 1 of the selected measuring point and the grounding down lead 1 of the reference point;
the current lead-in module is used for leading in constant direct current test current between the current pole 2 of the datum point and the current pole 2 of the measuring point;
the measuring module is used for measuring and recording the potential difference between the current pole 2 of the datum point and the voltage pole 3 of the measuring point, measuring the linear distance between the current pole 2 of the datum point and the measuring point on a power station plan view, and analyzing the material used by the conductor of the grounding down conductor 1 and measuring the cross section area of the conductor of the grounding down conductor 1;
the calculation module is used for calculating the actual on-resistance of the grounding grid by utilizing the potential difference between the current electrode 2 of the datum point and the voltage electrode 3 of the measuring point; calculating an ideal value of the on-resistance of the grounding grid according to the material used by the conductor of the grounding down-lead 1, the cross-sectional area and the linear distance between the current pole 2 of the datum point and the measuring point; calculating the ratio of an ideal value to an actual value of the on-resistance of the grounding grid;
and the evaluation module is used for evaluating the state of the grounding grid according to the ratio of the ideal value to the actual value of the on-resistance of the grounding grid.
In the specific implementation process, the selection module selects the grounding down lead as a measuring point of the on-resistance of the grounding grid, selects the grounding down lead of the main transformer as a reference point of the measuring point, and connects the current pole and the voltage pole of the on-power supply respectively on the grounding down lead of the selected measuring point and the grounding down lead of the reference point; the current lead-in module is used for leading in constant direct current test current between the current pole of the datum point and the current pole of the measuring point; the measuring module measures and records the potential difference between the current pole of the datum point and the voltage pole of the measuring point, measures the linear distance between the current pole of the datum point and the measuring point on the power station plan, and analyzes the materials used by the grounding down conductor and the cross section area of the grounding down conductor; the calculation module calculates the actual on-resistance of the grounding grid by utilizing the potential difference between the current pole of the datum point and the voltage pole of the measuring point; calculating an ideal value of the on-resistance of the grounding grid according to the materials used by the grounding down-lead conductor, the cross-sectional area and the linear distance between the current pole of the datum point and the measuring point; calculating the ratio of an ideal value to an actual value of the on-resistance of the grounding grid; and the evaluation module evaluates the state of the grounding network according to the ratio of the ideal value to the actual value of the on-resistance of the grounding network.
The terms describing the positional relationship in the drawings are merely illustrative, and are not to be construed as limiting the present patent;
it is to be understood that the above examples of the present invention are provided by way of illustration only and not by way of limitation of the embodiments of the present invention. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are desired to be protected by the following claims.
Claims (4)
1. The method for measuring the on-resistance of the grounding grid and evaluating the state of the grounding grid is characterized by comprising the following steps of:
s1: selecting a grounding down-lead as a measuring point of the on-resistance of the grounding grid, selecting the grounding down-lead of the main transformer as a reference point of the measuring point, and respectively connecting the grounding down-lead of the measuring point and the grounding down-lead of the reference point with a current pole and a voltage pole of the on-state power supply;
s2: a constant direct current test current is led in between the current pole of the datum point and the current pole of the measuring point; defining the first ground current as I+ and the second ground current as I-; a constant direct current test current is led in between the current pole of the datum point and the current pole of the measuring point, and simultaneously, a first ground current is led inI + And a second current to groundI - Setting zero; when the current direction of the direct current is the direction of the direct current flowing to the ground, the direct current is added up to the first ground currentI + The method comprises the steps of carrying out a first treatment on the surface of the When the current direction of the direct current is the flowing ground, the direct current is added up to the second ground currentI - ；
S3: measuring and recording the potential difference between the current pole of the datum point and the voltage pole of the measuring point, and measuring the linear distance between the current pole of the datum point and the measuring point on the power station plan;
s4: calculating the actual value of the on-resistance of the grounding grid by using the potential difference between the current pole of the datum point and the voltage pole of the measuring point；
S5: analyzing the material used by the grounding down conductor, calculating the cross section area of the grounding down conductor, and calculating the ideal value of the on-resistance of the grounding grid according to the material used by the grounding down conductor, the cross section area and the linear distance between the current pole of the measured datum point and the measuring point;
wherein if the grounding down conductor is a copper conductor, the on-resistance is idealR 1 The approximate calculation formula of (a) is:
wherein,Dfor the linear distance between the current pole of the measured reference point and the measurement point,Sa cross-sectional area of the ground down-conductor;
if the grounding down conductor is a steel conductor, the on-resistance is idealR 2 The approximate calculation formula of (a) is:
s6: calculating the ratio of the actual value to the ideal value of the on-resistance of the grounding grid, and evaluating the state of the grounding grid according to the ratio;
wherein, the ratio of the actual value to the ideal value of the on-resistance of the grounding grid is calculatedKThe calculation formula of (2) is as follows:
，i=1,2
wherein,R i representing ideal on-resistance of different ground down conductor materials;
the evaluating the state of the grounding network specifically comprises the following steps:
when (when)K<2, the grounding grid is good;
when 2 is less than or equal toKWhen the voltage is less than 5, the state of the grounding grid is still acceptable;
when the time is less than or equal to 5%KWhen the voltage is less than 50, the state of the grounding grid is poor;
when (when)KWhen the current is more than 50, the state of the grounding grid is extremely poor;
s7: and selecting the next measuring point, and jumping to execute the step S2 until all the measuring points are measured, and ending the measurement.
2. The method for measuring on-resistance of a ground network and evaluating the state of the ground network according to claim 1, wherein in the step S1, the ground down line selected as the measuring point of the on-resistance of the ground network includes a high voltage device, a low voltage device, a main control ground trunk line, an internal ground trunk line, an independent lightning rod or a ground down line of a microwave tower; if a plurality of main transformers are arranged, the grounding down-lead closest to the center of the grounding grid is selected as a reference point of the measuring point.
3. The method for measuring on-resistance of a ground network and evaluating a state of a ground network according to claim 1, wherein the steps between the step S3 and the step S4 further comprise the following steps: measuring the composite magnetic induction intensity of the conductor surface of the grounding down conductor between the datum point current pole and the measuring point and the composite magnetic induction intensity of the conductor surface of the steel framework in the power station by using a magnetometer; and if the composite magnetic induction intensity of the conductor surface of the grounding down conductor or the composite magnetic induction intensity of the conductor surface of the steel framework is larger than 0.005Oe, measuring constant direct current test current flowing on the conductor of the grounding down conductor or the conductor of the steel framework by using a flexible coil.
4. A system for measuring on-resistance of a ground network and evaluating state of the ground network, which is applied to the method for measuring on-resistance of a ground network and evaluating state of a ground network according to any one of claims 1 to 3, comprising:
the selection module is used for selecting the grounding down-lead as a measuring point of the on-resistance of the grounding grid, selecting the grounding down-lead of the main transformer as a reference point of the measuring point, and respectively connecting the current pole and the voltage pole of the on-power supply on the grounding down-lead of the selected measuring point and the grounding down-lead of the reference point;
the current lead-in module is used for leading in constant direct current test current between the current pole of the datum point and the current pole of the measuring point;
the measuring module is used for measuring and recording potential difference between the current pole of the datum point and the voltage pole of the measuring point, measuring the linear distance between the current pole of the datum point and the measuring point on the power station plan, and analyzing the material used by the grounding down-lead conductor and measuring the cross section area of the grounding down-lead conductor;
the calculation module is used for calculating the actual on-resistance of the grounding grid by utilizing the potential difference between the current pole of the datum point and the voltage pole of the measuring point; calculating an ideal value of the on-resistance of the grounding grid according to the materials used by the grounding down-lead conductor, the cross-sectional area and the linear distance between the current pole of the measured datum point and the measuring point; calculating the ratio of the actual value to the ideal value of the on-resistance of the grounding grid;
and the evaluation module is used for evaluating the state of the grounding grid according to the ratio of the actual value of the on-resistance of the grounding grid to the ideal value.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111095563.XA CN113866505B (en) | 2021-09-17 | 2021-09-17 | Grounding grid on-resistance measurement and grounding grid state evaluation method and system |
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| CN202111095563.XA CN113866505B (en) | 2021-09-17 | 2021-09-17 | Grounding grid on-resistance measurement and grounding grid state evaluation method and system |
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