A method for determining the installation height of a photovoltaic booster station PLP in plateau mountains

Abstract

The present invention discloses a method for determining the installation height of PLP of a photovoltaic booster station in a plateau mountainous area, and belongs to the field of lightning protection of a power system. The method comprises: measuring the surface area of ​​PLP protection required for lightning protection of a booster station, determining the height of the protected object of the booster station, and conducting on-site geological and topographic surveys of substations to determine the installation position and quantity of PLP; calculating and analyzing the protection range of PLP; determining the key points of the protected object of the booster station; determining the installation height of PLP; verifying that the protected object is within the protection range of PLP to achieve effective lightning protection for the entire station. The method for determining the installation height of PLP of a photovoltaic booster station in a plateau mountainous area of ​​the present invention is intuitive and simple, easy to operate and implement, and by constructing a discriminant formula for lightning protection key points of a booster station in a plateau mountainous area, a lightning protection design is carried out starting from the key points, which greatly simplifies the lightning protection design process of a photovoltaic booster station, improves the installation efficiency of PLP and the lightning protection effect of the booster station; a large amount of measured data shows that the method is simple and reliable, and can effectively improve the lightning protection effect of the booster station.

Description

Technical Field

[0001] The present invention belongs to the field of lightning protection for electric power systems, and in particular relates to a method for determining the installation height of a photovoltaic booster station (PLP) in plateau mountainous areas. Background Art

[0002] The booster station is an important hub of the power system and is responsible for the important task of power supply to the power grid. Its stable operation is crucial to the reliability and safety of the entire power grid. With the vigorous development of clean energy such as photovoltaic power generation, a large number of microelectronic circuits are equipped in photovoltaic booster stations, and photovoltaic booster stations are facing increasingly serious lightning disasters. The huge energy released by lightning discharge in the booster station will cause serious damage to power generation and transformation equipment, control systems, etc., and even cause the booster station to stop operating, causing economic losses. Therefore, the lightning protection design of the booster station is particularly important.

[0003] Historically, lightning rods and lightning arresters are usually used to protect substations from direct lightning strikes. The main idea of ​​lightning protection is to "lead lightning into the ground". Although the principle is simple, using metal tip discharge to lead lightning into the ground can easily cause hazards such as induced overvoltage, lightning overvoltage and electromagnetic shock.

[0004] PLP is a lightning protection device that mainly shields and concentrates thunderclouds. It uses the electric field of thunderclouds to achieve passive strong ionization. The strong ionization discharger generates high-concentration plasma that diverges bidirectionally from cloud to ground, neutralizes the charge of thunderclouds, and shields the equipment in the station from lightning, thereby achieving lightning protection.

[0005] The lightning protection design of the booster station is a process of repeated calculation and verification. In the lightning protection design of the booster station, due to the inconsistency of the size and layout freedom of each building, the size and position coordinates of each building have to be repeatedly substituted into the lightning protection formula in the traditional lightning protection design process to verify whether the buildings in the station are effectively protected. The process is cumbersome and the efficiency is extremely low. Due to the difference in the lightning protection principles of PLP and lightning rod, the installation of the PLP device cannot completely copy the installation method of the traditional lightning rod. Therefore, the present invention proposes a method for determining the installation height of the PLP of the plateau mountain photovoltaic booster station, which provides a new idea for the installation of the PLP of the plateau mountain photovoltaic booster station. Summary of the invention

[0006] The purpose of the present invention is to provide a method for determining the installation height of a plateau mountain photovoltaic booster station PLP. The prior art has the problems of cumbersome lightning protection design process and low installation efficiency for plateau mountain photovoltaic booster stations.

[0007] The present invention discloses a method for determining the installation height of a photovoltaic booster station (PLP) in a plateau mountainous area. The identification method comprises the following steps:

[0008] Step 1: Measure the surface area of ​​the booster station that needs PLP protection for lightning protection and determine the height h of the protected object of the booster station x , conduct on-site survey of the geological topography of the booster station to determine the installation location and quantity of PLP;

[0009] Step 2: Calculate and analyze the protection range of PLP and set the protection angle of the PLP device as θ;

[0010] The protection radius of a single PLP on the ground is:

[0011] (1)

[0012] Where h represents the installation height of PLP;

[0013] A single PLP The protection radius on the xx plane at height is:

[0014] (2)

[0015] in Indicates the height of the building;

[0016] Step 3: Determine the key points of the protected objects in the booster station;

[0017] +x(3)

[0018] Where f is the key value, is the distance between the building and the PLP.

[0019] According to formula (3), calculate the point in the booster station that can make f reach the maximum value. This point is the key point of the lightning protection design in the booster station. The distance from the key point to PLP is x d .

[0020] Step 4: Determine the installation height of PLP;

[0021] The building height at the key point , substituting into formula (2) we can get:

[0022] (4)

[0023] Step 5: Verify that the protected object is within the protection range of the PLP to achieve effective lightning protection for the entire site.

[0024] Preferably, the calculation and analysis of the protection range of the PLP in Step 1 comprehensively considers the layout and height of the structures within the station to ensure that no part of the protected object protrudes into the unprotected area.

[0025] Preferably, the protection angle of the PLP device in Step 2 is θ, which varies from 84° to 86° depending on the altitude and is determined according to the actual scenario.

[0026] Preferably, the key points of the protected objects in the booster station in Step 3 are some special points in the booster station. When the key points in the booster station are effectively protected by PLP, the buildings in the entire station can be effectively protected. That is, after the key points are determined, the lightning protection of the booster station only needs to consider the lightning protection design of the key points, and points in other locations can be automatically satisfied.

[0027] Preferably, the method for selecting key points of protected objects in the booster station in Step 3 is also effective and applicable to the selection of key points of booster stations in plain areas.

[0028] In the long-term lightning protection design, it is found that there are some special points in the substation. If these points can be effectively protected by lightning rods, all buildings in the entire station can be effectively protected. Therefore, the present invention proposes a fast judgment formula (3) using the spatial distribution position and height difference of the buildings in the station, which simplifies the lightning protection design of the substation, and calls this special point the key point of lightning protection of the booster station.

[0029] The discriminant (3) of the key points of the booster station protected object is established after utilizing the spatial distribution position and height difference of the buildings in the booster station. It can be seen from the discriminant (3) that the method for establishing the key points utilizes the spatial distribution position and height difference of the buildings in the station and the protection angle of the proposed PLP device. θ , which is not greatly affected by other factors. Therefore, it is not only suitable for booster stations in plateau mountains, but also effective for the selection of key points of booster stations in plain areas.

[0030] Preferably, the installation height of the PLP described in Step 4 is h Need to be smaller than the actual installation height of PLP h r , thereby preventing the edge area of ​​the booster station from protruding into the unprotected area.

[0031] Preferably, the actual installation height of PLP h r After confirmation, the actual installation height of PLP h r Substitute into formula (2) to reversely verify the protection scope of PLP and determine that the protected building is within the protection scope of PLP.

[0032] The present invention has the following beneficial technical effects:

[0033] The method for determining the PLP installation height of a plateau mountain photovoltaic booster station of the present invention is intuitive and simple, easy to operate and implement, and by constructing a discriminant formula for lightning protection key points of a plateau mountain booster station, lightning protection design is carried out based on key points, which greatly simplifies the photovoltaic booster station lightning protection design process, improves the PLP installation efficiency and the lightning protection effect of the booster station; the method is based on the lightning protection design of a plateau mountain photovoltaic booster station but is not limited to the terrain and area of ​​the booster station, and is suitable for determining the PLP installation height of various types of booster stations such as wind power booster stations and hydropower booster stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a flow chart of a method for determining the installation height of a photovoltaic booster station PLP in a plateau mountain area according to the present invention;

[0035] Figure 2 This is a diagram of the PLP device of the present invention;

[0036] Figure 3 This is a cross-sectional view of the protection range of a single lightning rod of the present invention;

[0037] Figure 4 A top view of the protection range of a single lightning rod of the present invention;

[0038] Figure 5 This is a schematic diagram of the installation position of a 220kV photovoltaic booster station PLP in a plateau mountain area according to Example 1 of the present invention;

[0039] Figure 6 This is a schematic diagram of the installation location of a 35kV photovoltaic booster station PLP in a plateau mountain area according to Example 2 of the present invention. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Embodiment 1:

[0042] like Figure 5 This is the general layout of a 220kV photovoltaic booster station in a plateau mountain area. The construction scale is as follows:

[0043] Main transformer h1=10.8m; reactive power compensation device h2=10.2m; station transformer and grounding transformer h3=6.5m; distribution room h4=4.6m; central control room h5=3.5m; switch station h max =9.8m; the area of ​​the booster station is: 90×86m 2 .

[0044] The specific steps to determine the PLP installation height are as follows:

[0045] Step 1. According to the topography, geology and safety distance requirements of the booster station, two equal-height lightning rods are used to protect the entire station from direct lightning strikes. They are installed at positions ① and ②.

[0046] Step 2: The outer side of PLP①② is considered as the protection range of a single lightning rod, and the inner abcd area is the protection overlapping area, and the protection angle θ is 84.3°;

[0047] Step 3, calculate the point in the booster station that can make f reach the maximum value according to formula (3);

[0048] h d =h3=6.5m,x ad =x bd =37.69m, f(x ad ,h d )=f(x bd ,h d )=45.75m

[0049] h c =h1=10.8m,x ac =x bc =39.36m, f(x ac ,h c )=f(x bc ,h c )=49.75m

[0050] h e =h2=10.2m,x ae =39.44m, f(x a ,h ae )=49.54m

[0051] h f =h max =9.8m,x bf =35.53m, f(x a ,h bf )=45.43m

[0052] Depend on Figure 5 From the simple geometric relationship, we can know that point c is the key point of this lightning protection design, h c =10.8m,x ac =x bc =39.36m, f(x ac ,h c )=f(x bc ,h c )=49.75m;

[0053] Step 4. Determine the installation height of PLP h ;

[0054] The building height h at the key point c Substituting into formula (4) we can get: m.

[0055] Considering that the installation height of 14.736m must be less than the actual installation height of PLP, two PLPs with an actual installation height of 16m are installed at points ① and ② respectively to provide lightning protection for the entire station.

[0056] Step 5: Verify that the protected object is within the protection scope of the PLP;

[0057] Substituting the actual installation height of PLP 16m into formula (2), we can obtain: r = 10 (16-10.8) = 52m > 39.36m.

[0058] This shows that this installation scheme can achieve effective lightning protection for the entire station.

[0059] Embodiment 2:

[0060] like Figure 6 This is the general layout of a 35kV photovoltaic booster station in a plateau mountain area. The construction scale is as follows:

[0061] Main transformer h1=3.5m; reactive power compensation device h2=3.5m; alarm room h3=3.9m; secondary equipment room h4=4.5m; 10kV indoor distribution room h5=4.1m; 35kV indoor distribution room h6=4.6m; the area of ​​the booster station is: 41×32m 2 .

[0062] The specific steps to determine the PLP installation height are as follows:

[0063] Step 1. According to the topography, geology and safety distance requirements of the booster station, two equal-height lightning rods are used to protect the entire station from direct lightning strikes. They are installed at positions ① and ②.

[0064] Step 2: The outer side of PLP①② is considered as the protection range of a single lightning rod, and the inner abcd area is the protection overlapping area, and the protection angle θ is 84.3°;

[0065] Step 3, calculate the point in the booster station that can make f reach the maximum value according to formula (3);

[0066] h d =h6=4.6m,x ad =24.2m, f(x ad ,h d )=30.98m

[0067] h d =h6=4.6m,x bd =22.3m, f(x bd ,h d )=29.08 m

[0068] h c =h5=4.1m,x ac =20m,f(x ac ,h c )=26.40m

[0069] h c =h5=4.1m,x bc =22.05m, f(x bc ,h c )=28.45 m

[0070] Depend on Figure 6 From the simple geometric relationship, we can know that point d is the key point of this lightning protection design, h d =4.6m,x ad =24.2m, f(x ad ,h d )=30.98m;

[0071] Step 4. Determine the installation height of PLP h ;

[0072] The building height at the key point Substituting into formula (4) we can get: m.

[0073] Considering that the installation height of 7.02m needs to be lower than the actual installation height of PLP, two PLPs with an actual installation height of 10m are installed at points ① and ② respectively to provide lightning protection for the entire station.

[0074] Step 5: Verify that the protected object is within the protection scope of the PLP;

[0075] Substituting the actual installation height of PLP 10m into formula (2), we can obtain: r = 10(10-4.6) = 54m>24.2m.

[0076] This shows that this installation scheme can achieve effective lightning protection for the entire station.

[0077] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for determining the installation height of a photovoltaic booster station PLP in a plateau mountainous area, characterized by: The steps of the method include: Step 1: Measure the surface area of ​​the booster station that needs PLP protection for lightning protection and determine the height h of the protected object of the booster station x , conduct on-site survey of the geological topography of the booster station to determine the installation location and quantity of PLP; Step 2: Set the protection angle of the PLP device as θ, and calculate and analyze the protection range of the PLP; The protection radius of a single PLP on the ground is: (1)； Where h represents the installation height of PLP; A single PLP The protection radius on the xx plane at height is: (2)； in Indicates the height of the protected object; Step 3: Determine the key points of the protected objects in the booster station; +x (3)； Where f is the key value, is the distance between the protected object and the PLP; According to formula (3), the point in the booster station where f can reach the maximum value is calculated. This point is the key point of the lightning protection design in the booster station. The distance from the key point to the PLP is x d； Step 4: Determine the installation height of PLP; The height of the protected object at the key point , substituting into formula (2) we can get: (4)； Step 5: Verify that the protected object is within the protection range of the PLP to achieve effective lightning protection for the entire site.

2. According to claim 1, a method for determining the installation height of a photovoltaic booster station PLP in a plateau mountainous area is characterized by: The protection angle θ of the PLP device described in Step 2 varies with altitude and takes a value of 84°-86°.

3. According to claim 1, a method for determining the installation height of a photovoltaic booster station PLP in a plateau mountainous area is characterized by: The method of determining the key points of the protected objects in the booster station in Step 3 is also applicable to the selection of key points of booster stations in plain areas.

4. According to claim 1, a method for determining the installation height of a photovoltaic booster station PLP in a plateau mountainous area is characterized by: The installation height of the PLP described in Step 4 h Need to be smaller than the actual installation height of PLP h r .

5. A method for determining the installation height of a photovoltaic booster station PLP in a plateau mountain area according to claim 4, characterized in that: The Step 5 is specifically as follows: The actual installation height of PLP h r Substitute into formula (2) to reversely verify the protection scope of PLP and confirm that the protected object is within the protection scope of PLP.

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