阅读说明：本技术 一种直流输电线下电场强度检测系统与方法 (System and method for detecting electric field intensity under direct-current transmission line ) 是由 翟国庆 项君莉 董丽 李军 于 2021-09-07 设计创作，主要内容包括：本发明公开了一种直流输电线下电场强度检测系统,包括：氢气球探头,能在静风条件下悬浮于空气中；带正电荷的氢气球,用于使氢气球探头带正电荷；带负电荷的氢气球,用于使氢气球探头带负电荷；摄像头,用于拍摄带电荷的氢气球探头在电场下的运动轨迹,并将视频实时传输至计算机；计算机,用于记录氢气球探头所处位置的三维坐标,并根据所述三维坐标计算出氢气球探头所处任意位置处的电场强度；本发明公开了一种直流输电线下电场强度检测方法；本发明系统成本较低,本发明方法能连续测量直流输电线下不同位置处的电场强度,且操作简单。(The invention discloses a system for detecting the electric field intensity under a direct current transmission line, which comprises: a hydrogen balloon probe capable of suspending in air under calm wind conditions; a hydrogen balloon with positive charge for making the hydrogen balloon probe have positive charge; a negatively charged hydrogen balloon for negatively charging the hydrogen balloon probe; the camera is used for shooting the motion track of the hydrogen balloon probe with charges under the electric field and transmitting the video to the computer in real time; the computer is used for recording the three-dimensional coordinates of the position of the hydrogen balloon probe and calculating the electric field intensity of any position of the hydrogen balloon probe according to the three-dimensional coordinates; the invention discloses a method for detecting the electric field intensity under a direct current transmission line; the system of the invention has lower cost, the method of the invention can continuously measure the electric field intensity at different positions under the direct current transmission line, and the operation is simple.)

1. The utility model provides an electric field strength detecting system under direct current transmission line which characterized in that includes:

a hydrogen balloon probe capable of suspending in air under calm wind conditions;

a hydrogen balloon with positive charge for making the hydrogen balloon probe have positive charge;

a negatively charged hydrogen balloon for negatively charging the hydrogen balloon probe;

the camera is used for shooting the motion track of the hydrogen balloon probe with charges under the electric field and transmitting the video to the computer in real time;

and the computer is used for recording the three-dimensional coordinates of the position of the hydrogen balloon probe and calculating the electric field intensity of any position of the hydrogen balloon probe according to the three-dimensional coordinates.

2. The system for detecting the electric field strength under the direct current transmission line according to claim 1, further comprising an insulating container having three cavities, namely a left cavity, a middle cavity and a right cavity, wherein the hydrogen balloon probe is placed in the cavity close to the electric field to be detected, and the hydrogen balloon with positive charge and the hydrogen balloon with negative charge are respectively placed in the other two cavities; except the bottom surface and the side surface connected with the middle cavity, the top surface and the other three side surfaces of the cavity where the hydrogen balloon probe is located can be folded outwards.

3. The system of claim 2, wherein an electrode M is disposed at the center of the bottom of each chamber_{Is just}、M_{Negative pole}And P_MThe three electrodes are respectively contacted with a hydrogen balloon with positive charge, a hydrogen balloon with negative charge and a hydrogen balloon probe, and are all wrapped by insulating rubber sleeves.

4. The system for detecting the electric field strength under the direct current transmission line according to claim 1, wherein the hydrogen balloon probe is a hydrogen balloon wrapped by a metal film.

5. The system for detecting the electric field strength under the direct current power transmission line according to claim 1, wherein the cameras comprise a first camera and a second camera for shooting the motion tracks of the hydrogen balloon probe in different planes.

6. A method for detecting electric field intensity under a direct current transmission line, characterized in that the detection system of any one of claims 1 to 5 is adopted, and the method comprises the following steps:

1) under the condition of calm wind, setting the position of the probe releasing the hydrogen balloon as a coordinate origin, and establishing a three-dimensional coordinate system; the positive directions of the x axis, the y axis and the z axis are respectively the initial moving directions of the hydrogen balloon probe in the directions of the x axis, the y axis and the z axis after being released;

2) the two cameras are respectively arranged on an xz plane and a yz plane, the height of the two cameras is equal to the height of the position of the hydrogen balloon releasing probe, the horizontal distance from the hydrogen balloon releasing position is D, and the directions of the cameras are adjusted to enable the cameras to point to the position of the hydrogen balloon releasing probe for shooting;

3) charging the hydrogen balloon probe with positive or negative charges with the charge quantity q;

4) releasing the hydrogen balloon probe with charges, and starting to move under the action of the electric field to be detected;

5) recording the three-dimensional coordinates of the position of the hydrogen balloon probe according to the motion tracks of the hydrogen balloon probe shot by the two cameras and by utilizing an image processing technology at a time interval delta t;

6) and calculating the electric field intensity of any position where the hydrogen balloon probe is recorded in the step 5) according to the three-dimensional coordinates of the hydrogen balloon probe.

7. The method for detecting the electric field strength under the direct current transmission line according to claim 6, wherein the implementation method of the step 3) is as follows:

if the hydrogen ball probe is to be positively charged, the electrode P is connected_MAnd M_{Is just}Removing the rubber sleeve, and connecting the electrode P by a lead_MAnd M_{Is just}So that the hydrogen ball probe can have positive charge;

if the hydrogen gas ball probe is to be negatively charged, the electrode P is charged_MAnd M_{Negative pole}Removing the rubber sleeve, and connecting the electrode P by a lead_MAnd M_{Negative pole}The hydrogen gas ball probe can be negatively charged.

8. The method for detecting the electric field strength under the direct current power transmission line according to claim 6, wherein in the step 3), if the position for releasing the hydrogen balloon probe is close to the positive conductor of the direct current power transmission line, the hydrogen balloon probe is enabled to have positive charge; if the position of releasing the hydrogen balloon probe is close to the negative lead of the direct current power transmission line, the hydrogen balloon probe is required to carry negative charges.

9. The method for detecting the electric field strength under the direct current transmission line according to claim 6, wherein in the step 6), the recorded electric field strength at any position where the hydrogen balloon probe is located is calculated, and the method is implemented as follows:

at t₀At the moment, the hydrogen balloon probe starts moving from the release position (0, 0, 0), after n time intervals Δ t, at t_n(t_n＝t₀+ n Δ t), the hydrogen balloon moves to (x)_n，y_n，z_n)；

At t_nAt any moment, the electric field intensity E of the position where the hydrogen balloon probe is located_nThe calculation formula of (2) is as follows:

in the formula (1), E_x|n、E_y|nAnd E_z|nAre each at t_nAt any moment, the components of the electric field at the position of the hydrogen balloon probe in the directions of the x-axis, the y-axis and the z-axis can be respectively calculated by the following formulas:

formula (II)(2) In (1) to (4), x_n-1、x_n、x_n+1And x_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The x coordinate of the position of the hydrogen balloon probe at any moment; y is_n-1、y_n、y_n+1And y_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The y coordinate of the position of the hydrogen balloon probe at any moment; z is a radical of_n-1、z_n、z_n+1And z_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The z coordinate of the position of the hydrogen balloon probe at all times; m is the mass of the hydrogen balloon probe; q is the charge quantity carried by the hydrogen balloon probe;

at t_nTime of day, E_x|n、E_y|nAnd E_z|nThe direction of (2) is determined as follows:

at t_nAt time E_x|n＞0，E_x|nPointing to the positive direction of the x axis; if E_x|n＜0，E_x|nPointing in the negative x-axis direction. If E_y|n＞0，E_y|nPointing to the positive direction of the y axis; if E_y|n＜0，E_y|nPointing in the negative y-axis direction. If E_z|n＞0，E_z|nPointing to the positive direction of the z axis; if E_z|n＜0，E_z|nPointing in the negative z-axis direction.

10. The method according to claim 6, wherein after the detection of the electric field intensity, the hydrogen balloon probe is recovered and the charge on the hydrogen balloon probe is removed; the method for eliminating the charges carried by the hydrogen balloon probe comprises the following steps:

the metal grounding electrode is inserted to the depth of 1m below the wet ground, and the recovered hydrogen balloon probe is contacted with the grounding electrode, so that the charges carried by the probe can be removed.

Technical Field

The invention relates to the technical field of electric field intensity detection, in particular to a system and a method for detecting the electric field intensity under a direct current transmission line.

Background

The electric field strength is an important index for evaluating the electromagnetic environment near the direct current transmission line. China releases 'limit value of synthetic electric field of direct current transmission engineering and monitoring method thereof' in 5 months in 2020 (GB39220-2020), and the standard stipulates that 95% measured value of the synthetic electric field strength of places such as farmlands, gardens, pastures, livestock and poultry raising places, breeding water surfaces, roads and the like under direct current overhead transmission lines cannot exceed 30 kV/m.

The electric field strength under the direct current transmission line is generally measured by a field mill type direct current field strength detector, and the working principle is as follows: the probe of the field grinding type direct current field intensity detector consists of a rotatable shielding blade and a fixed induction blade, and when the direct current field intensity is measured, the shielding blade rotates at a high speed, so that the exposure area of the induction blade in a direct current electric field is periodically changed; further, the amount of induced electric charge accumulated on the surface of the induction blade also changes periodically, so that an alternating induced current signal is generated; the DC electric field strength can be determined by detecting the corresponding signal.

However, the field mill type dc field strength detector is expensive, cannot be used to determine the direction of the electric field to be detected, and only detects the field strength at a certain position each time, and the field strength at different positions needs to be measured again after changing the position of the field strength detector.

The patent specification with publication number CN107727947B discloses a device for detecting the intensity of a dc electric field by using the electrorheological effect of electrorheological fluid, which mainly comprises a bracket, a closed container, electrorheological fluid, a built-in slide rail, a through hole, a built-in pipe, a working ball, a reflective film, a laser emitting and receiving device, a lead wire and an electromagnetic valve. When the device is in an external electric field, the viscosity, the fluidity and the like of the electrorheological fluid are changed, so that the motion state of the working ball moving in the electrorheological fluid is changed, and finally, the output time of the laser transmitting and receiving device is different. The output time is transmitted to an industrial personal computer and then matched with a storage database to achieve the purpose of detecting the electric field intensity applied to the electrorheological fluid.

Patent specification with publication number CN111579889B discloses a device and method for detecting electric field strength under an extra-high voltage direct current transmission line, the device comprises: the device comprises an insulating support, a graphite plate arranged at the top of the insulating support and a container which is arranged on the graphite plate and is used for containing acid solution or alkali solution; and the bottom of the graphite plate is provided with a grounding wire. The method comprises the steps of placing a container filled with an acid solution or an alkali solution with fixed concentration at a position where the electric field intensity needs to be measured under an extra-high voltage direct current transmission line, measuring the pH value of the circle center position of the upper layer of the solution in the container by a colorimetric method, and determining the electric field intensity of a measuring point according to a relation model of the pH value and the electric field intensity E.

The above-mentioned devices are complicated in structure and the method is complicated in operation, so that it is necessary to develop a detection system and method for electric field strength under dc transmission line which is low in cost, simple in operation and capable of continuously measuring electric field strength at different positions.

Disclosure of Invention

The invention aims to provide a system for detecting the electric field strength under a direct current transmission line, which has the advantages of low system cost, capability of continuously measuring the electric field strengths at different positions under the direct current transmission line and simplicity in operation.

A system for detecting electric field strength under a direct current transmission line includes:

a hydrogen balloon probe capable of suspending in air under calm wind conditions;

a hydrogen balloon with positive charge for making the hydrogen balloon probe have positive charge;

a negatively charged hydrogen balloon for negatively charging the hydrogen balloon probe;

the camera is used for shooting the motion track of the hydrogen balloon probe with charges under the electric field and transmitting the video to the computer in real time;

and the computer is used for recording the three-dimensional coordinates of the position of the hydrogen balloon probe and calculating the electric field intensity of any position of the hydrogen balloon probe according to the three-dimensional coordinates.

The system is simple in design and low in cost, and can continuously measure the electric field intensity at different positions under the direct current transmission line.

Preferably, the hydrogen measuring device further comprises an insulating container with a left cavity, a middle cavity and a right cavity, the hydrogen balloon probe is placed in the cavity close to the electric field to be measured, and the hydrogen balloon with positive charges and the hydrogen balloon with negative charges are respectively placed in the other two cavities; except the bottom surface and the side surface connected with the middle cavity, the top surface and the other three side surfaces of the cavity where the hydrogen balloon probe is located can be folded outwards. The insulating container is a cuboid container.

The hydrogen balloon with positive charge and the hydrogen balloon with negative charge have the same charge quantity Q, and the size, the structure, the material and the like as those of the hydrogen balloon probe.

Preferably, an electrode M is respectively arranged at the center of the bottom surface of each cavity_{Is just}、M_{Negative pole}And P_MThe three electrodes are respectively contacted with a hydrogen balloon with positive charge, a hydrogen balloon with negative charge and a hydrogen balloon probe, and are all wrapped by insulating rubber sleeves.

Preferably, the hydrogen balloon probe is a hydrogen balloon wrapped by a metal film.

The diameter d of the hydrogen balloon probe is preferably 28cm, the mass m is smaller, preferably 14.8g, the thickness of a metal film wrapping the hydrogen balloon is uniform, and the hydrogen balloon probe is preferably made of lithium metal.

Preferably, the cameras comprise a first camera and a second camera which are used for shooting the motion tracks of the hydrogen balloon probe in different planes. The camera is preferably a high-speed camera.

Another objective of the present invention is to provide a method for detecting an electric field strength under a dc power transmission line, which includes the following steps:

1) under the condition of calm wind, setting the position (height from the ground is h) for releasing the hydrogen balloon probe as a coordinate origin, setting a certain horizontal direction as an x-axis, setting another horizontal direction perpendicular to the x-axis as a y-axis, and setting a vertical direction as a z-axis, and establishing a three-dimensional coordinate system; the positive directions of the x axis, the y axis and the z axis are respectively the initial moving directions of the hydrogen balloon probe in the directions of the x axis, the y axis and the z axis after being released;

2) the two cameras are respectively arranged on an xz plane and a yz plane, the height of the two cameras is equal to the height of the position of the hydrogen balloon releasing probe, the horizontal distance from the hydrogen balloon releasing position is D, and the directions of the cameras are adjusted to enable the cameras to point to the position of the hydrogen balloon releasing probe for shooting;

specifically, two height-adjustable supports are respectively arranged on the ground which is positioned on an xz plane and a yz plane and has a horizontal distance D from the release position of the hydrogen balloon probe, two cameras are respectively fixed at the tops of the supports, and the height of the supports is adjusted to enable the two cameras to be as high as the position of the hydrogen balloon probe to be released (the height above the ground is h);

3) charging the hydrogen balloon probe with positive or negative charges with the charge quantity q;

4) releasing the hydrogen balloon probe with charges, and starting to move under the action of the electric field to be detected;

specifically, the top surface and the three movable side surfaces of the cavity where the hydrogen balloon probe is located in the insulating cuboid container are turned outwards, the insulating container is rapidly evacuated, and at the moment, the hydrogen balloon probe starts to move under the action of an electric field to be detected;

5) recording three-dimensional coordinates of the position of the hydrogen balloon probe according to the motion tracks of the hydrogen balloon probe shot by the two cameras and by utilizing an image processing technology according to a time interval delta t (delta t is the time interval between two adjacent frames of images shot by the cameras);

under the calm wind condition, the ion flow exists under the direct current transmission line, and the charged hydrogen balloon probe can cause the charged loss after contacting the ground, if the hydrogen balloon probe moves to the position under the direct current transmission line or contacts the ground, the recording is stopped;

6) calculating the electric field intensity of any position where the hydrogen balloon probe recorded in the step 5) is located according to the three-dimensional coordinates of the hydrogen balloon probe;

specifically, the calculation is carried out through the three-dimensional coordinates of the hydrogen balloon probe and Newton's second law.

Preferably, the implementation method of step 3) is as follows:

if the hydrogen ball probe is to be positively charged, the electrode P is connected_MAnd M_{Is just}Removing the rubber sleeve, and connecting the electrode P by a lead_MAnd M_{Is just}So that the hydrogen ball probe can be positively charged, and the charged quantity Q is Q/2;

if the hydrogen gas ball probe is to be negatively charged, the electrode P is charged_MAnd M_{Negative pole}Removing the rubber sleeve by adopting a leadConnecting electrode P_MAnd M_{Negative pole}The hydrogen ball probe is charged negatively, and the charged amount Q is Q/2.

Preferably, in the step 3), if the position of releasing the hydrogen balloon probe is close to the positive lead of the direct current power transmission line, the hydrogen balloon probe is enabled to have positive charge; if the position of the hydrogen balloon probe is close to the negative lead of the direct current power transmission line, the hydrogen balloon probe is provided with negative charges so as to prevent the hydrogen balloon from moving to the vicinity of the power transmission line under the action of electric field force and leading the hydrogen balloon probe to be difficult to recover.

Preferably, in step 6), the recorded electric field intensity at any position where the hydrogen balloon probe is located is calculated, and the method is implemented as follows:

at t₀At the moment, the hydrogen balloon probe starts moving from the release position (0, 0, 0), after n time intervals Δ t, at t_n(t_n＝t₀+ n Δ t), the hydrogen balloon moves to (x)_n，y_n，z_n) (ii) a Because the delta t is smaller, the hydrogen balloon probe can be regarded as being acted by constant electric field force in the delta t time interval and respectively does uniform variable-speed linear motion in the directions of the x axis, the y axis and the z axis.

At t_nAt any moment, the electric field intensity E of the position where the hydrogen balloon probe is located_nThe calculation formula of (2) is as follows:

in the formula (1), E_x|n、E_y|nAnd E_z|nAre each at t_nAt any moment, the components of the electric field at the position of the hydrogen balloon probe in the directions of the x-axis, the y-axis and the z-axis can be respectively calculated by the following formulas:

in the formulae (2) to (4), x_n-1、x_n、x_n+1And x_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The x coordinate of the position of the hydrogen balloon probe at any moment; y is_n-1、y_n、y_n+1And y_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The y coordinate of the position of the hydrogen balloon probe at any moment; z is a radical of_n-1、z_n、z_n+1And z_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The z coordinate of the position of the hydrogen balloon probe at all times; m is the mass of the hydrogen balloon probe; q is the charge quantity carried by the hydrogen balloon probe;

the electric field strength is vector, and further determination is needed at t_nAt any moment, the intensity E of the electric field at the position of the hydrogen balloon probe_nIn the direction of (i.e. at t)_nTime of day, E_x|n、E_y|nAnd E_z|nThe direction of the sum of the three vectors. At t_nTime of day, E_x|n、E_y|nAnd E_z|nIs calculated by the equations (2) to (4) at t_nTime of day, E_x|n、E_y|nAnd E_z|nThe direction of (2) is determined as follows:

at t_nAt time E_x|n＞0，E_x|nPointing to the positive direction of the x axis; if E_x|n＜0，E_x|nPointing in the negative x-axis direction. If E_y|n＞0，E_y|nPointing to the positive direction of the y axis; if E_y|n＜0，E_y|nPointing in the negative y-axis direction. If E_z|n＞0，E_z|nPointing to the positive direction of the z axis; if E_z|n＜0，E_z|nPointing in the negative z-axis direction.

Preferably, after detecting the electric field intensity, the hydrogen balloon probe should be recovered and the charge on the hydrogen balloon probe should be removed.

The recycled hydrogen balloon probe can be electrified again by adopting the methodAgain for detecting the electric field strength. After the electric field intensity is detected for the first time, the charge quantity of the hydrogen balloon with positive charge or negative charge is changed to Q/2, so that the charge quantity Q of the hydrogen balloon probe after being charged again is equal to Q/4. By analogy, when the recovered hydrogen balloon probe is electrified again and used for detecting the electric field intensity for the k time, the electric charge quantity Q charged by the hydrogen balloon probe is Q/2^k。

The method for eliminating the charges carried by the hydrogen balloon probe comprises the following steps:

the metal grounding electrode is inserted to the depth of 1m below the wet ground, and the recovered hydrogen balloon probe is contacted with the grounding electrode, so that the charges carried by the probe can be removed.

The invention has the beneficial effects that:

the system has low cost, can continuously measure the electric field intensity at different positions under the direct current transmission line, and is simple to operate.

Drawings

FIG. 1 is a schematic diagram of the system arrangement of the present invention;

FIG. 2 is a schematic diagram of the top surface and three side surfaces of the cavity in which the hydrogen balloon probe is located in the insulated rectangular parallelepiped vessel according to the embodiment of the present invention are turned over;

FIG. 3 shows a determination at t in an embodiment of the present invention_nSchematic diagram of the direction of the electric field at the position of the hydrogen balloon probe at that moment.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

This embodiment detects the electric field intensity near the head of a human body when the human body stands on the ground near the positive conductor side in an area of a farmland spanned by a ± 800kV extra-high voltage direct current transmission line.

As shown in figure 1, the system for detecting the electric field strength under the DC power transmission line comprises a hydrogen balloon probe

1. The hydrogen generating device comprises an insulating cuboid container 2 with three cavities, a hydrogen balloon 3 with positive charges, a hydrogen balloon 4 with negative charges, two cameras 5, two height-adjustable supports 6, a data line 7, a computer 8 and a metal grounding electrode 9.

Wherein, the hydrogen balloon probe 1 is a hydrogen balloon wrapped by a lithium metal film with uniform thickness (0.01mm), can be suspended in air under the condition of calm wind, and has a diameter d of 28cm and a mass m of 14.8 g.

The hydrogen balloon probe comprises an insulating cuboid container 2 with three cavities, wherein a hydrogen balloon 3 with positive charges, a hydrogen balloon 4 with negative charges and a hydrogen balloon probe 1 are respectively arranged in the left cavity, the middle cavity and the right cavity of the insulating cuboid container, and the top surface and the other three side surfaces of the insulating cuboid container can be turned outwards except the bottom surface and the side surface connected with the middle cavity of the insulating cuboid container where the hydrogen balloon probe 1 is arranged.

A micro electrode M is respectively arranged at the center of the bottom surfaces of the three cavities_{Is just}、M_{Negative pole}And P_MThe three electrodes are respectively contacted with a hydrogen balloon 3 with positive charge, a hydrogen balloon 4 with negative charge and a hydrogen balloon probe 1 and are all wrapped by insulating rubber sleeves; the hydrogen balloon 3 with positive charge and the hydrogen balloon 4 with negative charge have the same charge quantity Q, and the size, the structure, the material and the like as those of the hydrogen balloon probe 1.

The camera 5 is a high-speed camera, and the time interval between two adjacent frames of images shot by the camera is delta t; the top of the height-adjustable bracket 6 is used for fixing the camera 5; the data line 7 is connected with the camera 5 and the computer 8 and transmits the shot video to the computer 8 in real time.

A method for detecting the electric field intensity under a direct current transmission line by using the detection system comprises the following specific steps:

1) under the condition of calm wind, the position of releasing the hydrogen balloon probe is set as the origin of coordinates, a certain horizontal direction is set as an x-axis, another horizontal direction perpendicular to the x-axis is set as a y-axis, and a vertical direction is set as a z-axis, so that a three-dimensional coordinate system is established. The positive directions of the x axis, the y axis and the z axis are the initial moving directions of the hydrogen balloon probe in the directions of the x axis, the y axis and the z axis after being released. According to the Chinese adult human body size (GB/T10000-1988), the average height of a male aged 18-60 is 167.8cm, and the height above the ground of the release position of the hydrogen balloon probe in the example is slightly higher than 167.8cm, namely 170cm, because the hydrogen balloon probe is continuously close to the ground under the action of an electric field force after being released;

2) two height-adjustable supports are respectively arranged on the ground positioned on an xz plane and a yz plane, and the horizontal distance D between each support and the release position of the hydrogen balloon is 20 m. Respectively fixing the two cameras at the top of the support, adjusting the height of the support to enable the height h of the two cameras to be 170cm from the ground, and adjusting the directions of the cameras to enable the cameras to point to the release positions of the hydrogen balloon probes for shooting;

3) an upper electrode P of the insulated rectangular container_MAnd M_{Is just}Removing the insulating rubber sleeve, and connecting the electrode P by a lead_MAnd M_{Is just}Making the hydrogen ball probe positively charged, and making the charged quantity Q equal to Q/2;

4) the top surface and the three movable side surfaces of the cavity where the hydrogen balloon probe is located in the insulating cuboid container are turned outwards as shown in fig. 2, the insulating container is rapidly withdrawn towards the left and the bottom, and the hydrogen balloon probe starts to move under the action of an electric field to be measured;

5) the three-dimensional coordinates of the position of the hydrogen balloon probe are recorded at time intervals at according to the motion trajectories of the hydrogen balloon probe photographed by the two cameras by using an image processing technique (a system for measuring the moving distance of a sphere by using a 3D camera as disclosed in patent specification with publication number CN 112802065A). Under the calm wind condition, the ion flow exists under the direct current transmission line, and the charged hydrogen balloon probe can cause the charged loss after contacting the ground, if the hydrogen balloon probe moves to the position under the direct current transmission line or contacts the ground, the recording is stopped;

6) according to the three-dimensional coordinates of the hydrogen balloon probe and Newton's second law, calculating the recorded electric field intensity at any position where the hydrogen balloon probe is located, wherein the method comprises the following steps:

at t₀At the moment, the hydrogen balloon probe starts moving from the release position (0, 0, 0), after n time intervals Δ t, at t_n(t_n＝t₀+ n Δ t), the hydrogen balloon moves to (x)_n，y_n，z_n) (ii) a Since Δ t is small, Δ t time intervalThe inner hydrogen balloon probe can be regarded as under the action of constant electric field force and respectively makes uniform variable-speed linear motion in the directions of an x axis, a y axis and a z axis.

At t_nComponent v of movement speed of hydrogen balloon probe in x-axis direction at moment_x|nComprises the following steps:

in the formula (5), x_n-1And x_n+1Are each at t_n-1And t_n+1The x coordinate of the position of the hydrogen balloon probe at that time.

At t_n+1Component v of movement speed of hydrogen balloon probe in x-axis direction at moment_x|n+1Comprises the following steps:

in the formula (6), x_nAnd x_n+2Are each at t_nAnd t_n+2The x coordinate of the position of the hydrogen balloon probe at that time.

At t_nTo t_n+1In, hydrogen balloon probe is in the even variable speed rectilinear motion of x axle direction, satisfies:

v_x|n+1＝v_x|n+a_x|nΔt (7)

in the formula (7), a_x|nIs at t_nAt the moment, the component of the motion acceleration of the hydrogen balloon probe in the x-axis direction is calculated according to the following formula:

in the formula (8), m is the mass of the hydrogen balloon probe; f_x|nIs at t_nAt any moment, the component of the electric field force applied to the hydrogen balloon probe in the x-axis direction is calculated according to the following formula:

F_x|n＝qE_x|n (9)

formula (9)In q, the charge quantity carried by the hydrogen balloon probe is shown; e_x|nIs at t_nAt that moment, the component of the electric field in the x-axis direction where the hydrogen balloon probe is located.

Combining equations (5) to (9) at t_nComponent E of the electric field in the x-axis direction at the location of the hydrogen balloon probe at that moment_x|nComprises the following steps:

in a similar manner, at t_nThe components E of the electric field in the directions of the y-axis and the z-axis at the moment when the hydrogen balloon probe is positioned_y|nAnd E_z|nRespectively as follows:

in formulas (3) and (4), y_n-1、y_n、y_n+1And y_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The y coordinate of the position of the hydrogen balloon probe at any moment; z is a radical of_n-1、z_n、z_n+1And z_n+2Are each at t_n-1、t_n、t_n+1And t_n+2The z coordinate of the location of the hydrogen balloon probe at that time.

At t_nAt any moment, the electric field intensity E of the position where the hydrogen balloon probe is located_nThe calculation formula of (2) is as follows:

the electric field strength is vector, and further determination is needed at t_nAt any moment, the intensity E of the electric field at the position of the hydrogen balloon probe_nIn the direction of (i.e. at t)_nTime of day, E_x|n、E_y|nAnd E_z|nThe directions of the three vector sums are as shown in fig. 3. At t_nTime of day, E_x|n、E_y|nAnd E_z|nThe magnitude of (2) can be calculated by the following equations (2) to (4), and the direction can be determined by the following method:

at t_nAt time E_x|n＞0，E_x|nPointing to the positive direction of the x axis; if E_x|n＜0，E_x|nPointing in the negative x-axis direction. If E_y|n＞0，E_y|nPointing to the positive direction of the y axis; if E_y|n＜0，E_y|nPointing in the negative y-axis direction. If E_z|n＞0，E_z|nPointing to the positive direction of the z axis; if E_z|n＜0，E_z|nPointing in the negative z-axis direction.

7) After detecting the electric field intensity, the metal grounding electrode is inserted to the depth of 1m below the wet ground, and the hydrogen balloon probe is recovered and is contacted with the grounding electrode, so that the charges carried by the probe can be removed. And (4) recovering the hydrogen balloon probe, repeating the step 3), and electrifying the hydrogen balloon probe again and using the hydrogen balloon probe for detecting the electric field intensity again. Since the charged amount of the hydrogen balloon charged with positive charges is Q/2 after the electric field intensity is detected for the first time, the charged amount Q of the hydrogen balloon probe charged again is Q/4. By analogy, when the hydrogen balloon probe is recovered and electrified for detecting the electric field intensity for the k time, the charged quantity Q of the hydrogen balloon probe is Q/2^k。

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.