CN103175998B - A kind of portable test shaft tower detected for transmission circuit insulator string high-voltage performance - Google Patents

Abstract

A portable test pole tower for testing the high-voltage performance of transmission line insulator strings. The test tower body adopts a frame structure, and the bottom ends of the two pillars (3) are fixed to the concrete pouring foundation (2) by pre-embedded anchor bolts (1) , set two synchronous electric hoists (8) with self-locking function in the center of the fixed cross arm (5) at the top of the pillar (3), respectively pass the fixed pulley (12) on the inner side of the two pillars (3) close to the top with the wire rope (10) It is connected with both ends of the movable cross arm (6) below the fixed cross arm (5), and the movable cross arm (6) forms a guide rail pair (7) with the fixed guide rails (4) arranged inside the two pillars (3). The invention is easy to assemble, can be used for detecting the high-voltage performance of a single string of insulators, and can also be used for detecting the mutual influence of electrical properties between multi-phase insulators.

Description

A portable test tower for testing the high-voltage performance of transmission line insulator strings

technical field

The invention relates to the field of high-voltage electric power system, in particular to the structural field of a high-voltage performance detection test device for transmission equipment such as transmission line fittings and insulator strings.

Background technique

The high-voltage transmission line is an important part of the power system, and the safe and stable operation of the transmission line directly determines the safety and stability of the power system and the reliability of power supply. The operation performance and anti-interference performance of transmission equipment such as insulator strings and line fittings, protection equipment such as lightning arresters and transformers, and secondary equipment and anti-interference performance are the basis for ensuring the safe and stable operation of transmission lines, especially the insulator strings are responsible for the line-to-ground and other The insulation between objects is the most basic equipment for transmission lines. Insulator strings with different structural sizes, different materials, and operating in different environments have different insulation properties. The insulation performance of the insulator strings will also change when they are matched with other fittings on the line. In order to ensure the actual operating performance and anti-interference performance of the insulator strings after hanging , it is usually necessary to check the power frequency withstand voltage and power frequency flashover voltage (for insulator strings for AC lines), DC withstand voltage and DC flashover voltage (for insulator strings for DC lines) of insulator strings or insulator strings with other fittings ) and lightning impulse overvoltage, operating impulse overvoltage and other characteristics to conduct a series of high-voltage electrical performance testing tests.

Usually the above-mentioned electrical performance test is carried out on the real-type tower, but the real-type tower has high construction cost, long construction period, bulky and bulky, occupies a lot of land, and once one type of tower is built, it is not easy to refit and build it into another tower type, thus Insulator strings or insulator strings combined with other fittings cannot be tested for electrical performance under different layout forms, and the utilization rate of the tower is not high; Working at heights not only increases the risk of operators, but also is inconvenient to operate, time-consuming and labor-intensive, requiring more coordinating personnel and low work efficiency. Therefore, it is necessary to propose a portable test tower that can effectively solve the above-mentioned inherent shortcomings in the electrical performance testing of the real tower.

Contents of the invention

The technical problem to be solved by the present invention is: to solve the problem that line insulator strings or insulator strings cooperate with other fittings and other equipment to perform various high-voltage electrical performance testing tests that require true-type towers, and the construction period of true-type towers is long and the cost is high. It is inconvenient to hang, replace and adjust the insulator string of the test product, and it needs to work at heights, resulting in low efficiency and high risk.

The invention provides a convenient pole tower that can be used for insulator strings or insulator strings in conjunction with other equipment such as other fittings to perform the above-mentioned high-voltage electrical performance detection test. The test pole tower is easy to assemble, has a short construction period, low cost, and occupies less land. Practical, the use of the test tower avoids high-altitude operations when hanging, replacing and adjusting the insulator strings of the test product, and can perform high-voltage electrical performance testing tests of insulator strings or insulator strings with other fittings in different layout forms, greatly improving The tower utilization rate is improved, while reducing the number of operators and improving work efficiency.

The technical scheme adopted in the present invention is:

A portable test pole tower for testing the high-voltage performance of insulator strings in transmission lines. The invention is characterized in that the test tower body adopts a frame structure, the two pillars and the fixed cross arms at the top are fixed by connecting flanges, and the bottom ends of the two pillars are pre-buried. The anchor bolts are fixed to the foundation of concrete pouring, and two synchronous electric hoists with self-locking function are installed in the center of the fixed cross arm at the top of the pillar, and the steel wire rope for the fixed pulley near the top on the inner side of the two pillars and the movable cross arm under the fixed cross arm are respectively connected to each other. The two ends of the pole are connected, and the moving cross arm and the fixed guide rails set on the inside of the two pillars form a guide rail pair.

The movable cross-arm can freely slide up and down in the vertical plane along the fixed guide rail, driving the test insulator string connected with the movable cross-arm to move up and down, thereby raising and lowering the test insulator string and adjusting the height of the test insulator string to the ground.

The synchronous electric hoist with self-locking function in the center of the fixed cross arm at the top of the pillar can ensure that the moving cross arm below the fixed cross arm can rise and fall smoothly along the fixed guide rail. The cross arm and the test insulator string are fixed at a certain height from the ground.

The steel wire rope of the electric hoist of the present invention is connected with the movable cross arm through the electrical isolation insulator, which ensures reliable electrical isolation between the electric hoist (8) and the high voltage during the high voltage test.

The connecting rod for hanging the test insulator strings of the present invention can be flexibly disassembled and installed on the movable cross arm, and is used for adjusting the layout of the test insulator strings and the electrical gap between the test insulator strings or between the test insulator strings and the pillars.

The two sides of the electric hoist protective cover on the fixed cross arm of the present invention respectively chisel out a round hole to lead out the steel wire rope, to protect the electric hoist.

The basic steps of the present invention when carrying out the high-voltage electrical performance detection test are as follows:

(1) Operate the synchronous electric hoist by remote control, so that the moving cross arm will drop steadily along the fixed guide rail until it is convenient to manually cut off the power at the height above the ground where the test insulator string is installed on the moving cross arm. The electric hoist locks itself, and the moving cross arm bear fixed;

(2) According to the test content and test plan, according to the arrangement type of the test insulator string and various electrical clearances, determine the position and length of the connecting rod on the moving cross arm and fix it well, hang the test insulator string, and connect the high-voltage lead wire and ground, etc.;

(3) Operate the synchronous electric hoist by remote control to make the moving cross arm rise steadily along the fixed guide rail until the power is cut off at the height of the test insulator string from the ground required by the test, the electric hoist is self-locking, and the moving cross arm and the test insulator string are fixed;

(4) Carry out the high-voltage electrical performance testing test according to the test arrangement;

(5) After the test is completed, operate the synchronous electric hoist again by remote control, so that the moving cross arm can be lowered steadily along the fixed guide rail until the power is cut off at the position where it is convenient to manually replace or adjust the height above the ground of the insulator string of the test product, and the electric hoist automatically Lock, mobile cross arm fixed;

(6) According to the test content and test plan, replace or adjust the test insulator string on the ground, repeat steps (2), (3), (4), and (5) until the test is completed;

(7) After all the tests are completed, operate the synchronous electric hoist by remote control, so that the moving cross arm will drop steadily along the fixed guide rail until the power is cut off at the height above the ground where it is convenient for manual removal of the test insulator string on the ground. bear fixed;

(8) Remove the insulator string of the test product, and operate the synchronous electric hoist remotely to lower the moving cross arm to the ground so that the wire rope is not stressed.

The invention has the advantages of novel structure, ingenious conception, convenient implementation, low cost, small risk and high efficiency. Specifically, it has the following advantages:

(1) Remotely operate the synchronous electric hoist to control the mobile cross arm to slide freely up and down in the vertical plane on the fixed guide rail, and then control the different heights of the test insulator strings from the ground, avoiding high-altitude operations, reducing operation risks, and improving work efficiency. Usually, it is necessary to hang, replace and adjust the insulator string of the test product many times during the high-voltage electrical performance testing test. When operating on the real tower, an aerial work vehicle is required to cooperate. There are many operators, the work efficiency is low, and there are operators when working at altitude. Risk of falling from height. This portable test pole tower only needs to operate the synchronous electric hoist remotely to lower the mobile cross arm to a height convenient for manual operation when suspending, replacing and adjusting the insulator string of the test product. Fewer personnel, while improving work efficiency.

(2) Low construction cost and short construction period. Generally, the real-type towers used for electrical performance testing and testing mostly adopt the space truss structure with section steel connected by bolts or welded together. long. The portable test pole tower adopts frame structure and segmented assembly form. The manufacturer first produces the assembly sections, connecting flanges, guide rails, connectors, etc. required for the test tower in the workshop according to the design drawings. At the same time, the pillar foundation can be carried out. The concrete pouring construction with pre-embedded anchor bolts and the preparation of the synchronous electric hoist with self-locking function. After the above preparatory work is completed, the test tower can be assembled on site through the flange. The construction process is simple, and the main body of the test tower is a pole section made of high-strength hard aluminum alloy, which is light and easy to transport. Under the premise, the required tower material is less than that of the iron tower, which reduces the cost and shortens the construction period.

(3) The connecting rods used to connect the test insulator strings on the movable cross arm are easy to disassemble, and the layout of the test insulator strings and the electrical gap between the test products or between the test products and the pillars can be adjusted, so it can meet all kinds of high voltage Requirements for different gap distances in electrical performance testing tests.

Description of drawings

Fig. 1 is a schematic diagram of the structure of a portable test pole tower for the detection of the high-voltage performance of a three-phase insulator string of a transmission line according to the present invention;

Fig. 2 is a high-voltage performance detection diagram of the present invention used in three-phase insulator strings matching arcing angles of transmission lines.

In the figure: 1. Anchor bolts; 2. Pillar foundation; 3. Hard aluminum alloy section assembly pillar; 4. Cast iron fixed guide rail; 5. Hard aluminum alloy section assembly and fixed cross arm; 6. Hard aluminum alloy section assembly Moving cross arm; 7. Partial enlarged top view of the contact part of guide rail pair; 8. Synchronous electric hoist with self-locking function; 9. Protective cover of electric hoist; 10. Wire rope of electric hoist; 11. Electric isolation insulator of electric hoist; 12. Fixed pulley ; 13. Connecting flange; 14. Connecting rod; 15. Test insulator string; 16. Upper and lower electrodes of arcing angle;

detailed description

Below, the specific implementation manners of the present invention will be further described in conjunction with the accompanying drawings.

A portable test tower for testing the high-voltage performance of transmission line insulator strings. The present invention is characterized in that the test tower body adopts a frame structure, and the two pillars 3 and the fixed cross arm 5 at the top are fixed by connecting flanges 13. The two pillars 3 bottom The end is fixed with the concrete pouring foundation 2 by pre-embedded anchor bolts 1, and two synchronous electric hoists 8 with self-locking function are installed in the center of the fixed cross arm 5 on the top of the pillar 3, respectively passing through the fixed pulleys on the inner side of the two pillars 3 near the top 12 is connected with the mobile cross arm 6 two ends of fixed cross arm 5 below with steel wire rope 10, and the fixed guide rail 4 that moves cross arm 6 and two pillars 3 inner sides that are provided with forms guide rail pair 7.

The movable cross arm 6 can freely slide up and down in the vertical plane along the fixed guide rail 4, and drives the test insulator string 15 connected with the movable cross arm 6 to move up and down, thereby lifting and lowering the test insulator string 15 and adjusting the height of the test insulator string 15 to the ground .

The synchronous electric hoist 8 with self-locking function in the center of the fixed cross arm 5 at the top of the pillar 3 of the present invention can ensure that the moving cross arm 6 below the fixed cross arm 5 can move up and down smoothly along the fixed guide rail 4. The gourd 8 is self-locking when power is off, and the movable cross arm 6 and the test insulator string 15 are fixed at a certain height from the ground.

The electric hoist steel wire rope 10 of the present invention is connected to the movable cross arm 6 through the electrical isolation insulator 11, which ensures reliable electrical isolation between the electric hoist 8 and the high voltage during the high voltage test.

The connecting rod 14 for suspending the test insulator string 15 of the present invention can be flexibly disassembled and installed on the movable cross arm 6 for adjusting the layout of the test insulator string 15 and between the test insulator strings 15 or between the test insulator string 15 and the pillar 3 electrical clearance between them.

The both sides of the electric hoist protective cover 9 on the fixed cross arm 5 of the present invention respectively chisel out a circular hole and lead the wire rope 10, to protect the electric hoist.

As shown in Fig. 1 and Fig. 2, the present invention is generally composed of six major parts: foundation, pillar, fixed crossarm, movable crossarm, guide rail pair and synchronous electric hoist with self-locking function, among which pillar, fixed crossarm, mobile The cross arm is made of duralumin alloy, which is processed by the manufacturer in standard sections in the workshop, including connecting flanges, connecting rods, anchor bolts, and various connecting screws. The guide rail pair used in this test tower, the fixed guide rail (vertically placed guide rail) is made of hard wear-resistant cast iron, and the moving guide rail (horizontally placed guide rail) is composed of two parts: the movable cross arm and the hard aluminum alloy guide rail head, and the surface of the guide rail head is sprayed with a layer The wear-resistant coating, the guide rail head and the moving cross arm are reliably connected through the two-way flange to form a moving guide rail.

After the above preparatory work is completed, all the parts required for the test tower can be transported to the site to start the construction of the test tower. The basic steps for the construction of the test tower are as follows:

(1) Assemble the tower sections into pillars, fixed cross-arms and movable crosspieces on the ground;

(2) Connect the pillar and the fixed cross arm through the flange, configure and debug the synchronous electric hoist in the center of the fixed cross arm, and install the fixed guide rail inside the two pillars;

(3) Use a crane to hoist the test pole tower assembled on the ground to the position of the poured concrete pillar foundation, and keep the test pole tower vertical to the foundation;

(4) Fix the tower feet of the two pillars on the pre-embedded anchor bolts in the concrete foundation (here, if there are special requirements for the stability of the tower, you can also lead four stay wires at the top of the two pillars and fix them on the on the ground);

(5) Connect the guide rail head and the mobile cross arm through the flange, and use the crane to transport the mobile cross arm to the fixed pole tower foot;

(6) Connect the synchronous electric hoist to the two ends of the moving crosspiece with steel wire ropes through the electrical isolation insulator, and align the guide rail heads at both ends of the moving crossarm with the fixed guide rail;

(7) Remotely operate the synchronous electric hoist to lift the mobile cross arm along the fixed guide rail, and the construction of the portable test tower is completed.

As an example, the lightning impulse U _50% discharge characteristic of the 220kV composite insulator string with the strike arc angle is tested by using the portable pole tower for the test invented by the present invention, as shown in Figure 2, wherein the test product is composed of composite insulator string, stroke arc Composition of arc angle and simulated wire. Due to the different lightning impulse characteristics under different insulator string lengths and different arc strike angle sizes, the test needs to frequently replace the test insulator string and arc strike angle.

According to the relevant test regulations, the lightning impulse U _50% discharge characteristics are obtained by the lifting method. The main test steps are: first select 10% of the expected U _50% as the voltage difference ΔU, and select a voltage close to 50% of the flashover voltage as the Start the voltage and pressurize it. If there is no flashover, the voltage will increase by ΔU, otherwise, the voltage will decrease by ΔU in the next test; then determine the first effective starting voltage value, which is different from the effect produced by the previous test. The first test is selected as the first "effective" test, only this test and at least 9 subsequent tests are considered valid tests, and they are used to determine the 50% flashover voltage, which is calculated using the following formula .

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 50</span>}<span\; class="notranslate">\; \%</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; no</span>}}$

The main steps of the lightning impulse U _50% discharge characteristic test of 220kV composite insulator strings with the arc angle are as follows:

(1) Operate the synchronous electric hoist by remote control, so that the moving cross arm will drop steadily along the fixed guide rail until the power is cut off at the height above the ground where it is convenient to manually install the test product on the moving cross arm on the ground, the electric hoist is self-locking, and the moving cross arm is fixed ;

(2) According to the test plan, according to the installation type of the composite insulator string and the arc angle, determine the position and length of the connecting rod on the moving cross arm and fix it well, hang the composite insulator string, the arc angle and the simulated wire, etc., at the same time Connect the high-voltage leads and ground wires, etc.;

(3) Operate the synchronous electric hoist by remote control, so that the moving cross arm rises steadily along the fixed guide rail, until the power is cut off at the safe height above the ground required by the test, the electric hoist locks itself, and the moving cross arm and the sample are fixed;

(4) Start the test according to the test procedure of lightning impulse discharge characteristic U _50% , and make a record;

(5) Operate the synchronous electric hoist again by remote control, so that the moving cross arm will descend steadily along the fixed guide rail until the power is cut off at the height above the ground where the test product is convenient for manual operation on the ground, the electric hoist is self-locking, and the moving cross arm is fixed;

(6) According to the test plan, adjust the size of the arcing angle on the ground, repeat steps (2), (3), (4), and (5) until the lightning impulse characteristic tests of the composite insulator strings with different sizes of the arcing angle are all completed ;

(7) After all the tests are completed, operate the synchronous electric hoist by remote control to make the moving cross-arm drop steadily along the fixed guide rail until the power is cut off at the height above the ground where it is convenient to manually remove the test product on the ground, the electric hoist locks itself, and the moving cross-arm is fixed ;

(8) Remove the test product, and operate the synchronous electric hoist by remote control to lower the moving cross arm to the ground so that the wire rope is not stressed.

The test results of lightning impulse discharge characteristics U _50% of composite insulator series with parallel gap are as follows, in which the upper electrode of the arcing angle is rod-shaped, and the lower electrode is racket-shaped. When the ratio of arc angle gap length to composite insulator string structure height is 0.80, the test results of the lightning impulse U _50% discharge characteristic are shown in Table 1, and the lightning impulse discharge characteristic U _50% is 953.86kV.

Table 1

Claims (1)

1. A portable test pole tower for testing the high-voltage performance of transmission line insulator strings, characterized in that the test tower body adopts a frame structure, and the bottom ends of the two pillars (3) adopt pre-embedded anchor bolts (1) and concrete pouring The foundation (2) is fixed, and the center of the fixed cross arm (5) on the top of the pillar (3) is equipped with two synchronous electric hoists (8) with self-locking function, and the two electric hoists pass through the inner side of the two pillars (3) near the top. The fixed pulley (12) is connected with the two ends of the movable cross arm (6) under the fixed cross arm (5) by a steel wire rope (10), and the movable cross arm (6) is composed of the fixed guide rail (4) arranged inside the two pillars (3) The pair of guide rails (7), the connecting rod (14) for suspending the test insulator string (15) can be flexibly and detachably installed on the mobile cross arm (6), and the steel wire rope (10) and the mobile cross arm (6) are electrically isolated through the insulator ( 11) Connect.