CN104901255A - High-voltage overhead line crossing method and safe distance separating device - Google Patents

Abstract

A method for cross-drilling high-voltage overhead lines. When two high-voltage overhead lines with different voltage levels cross and cross, a safety distance separation device is provided at the intersection of the two. Also provided is a safety distance spacing device for cross-drilling of high-voltage overhead lines, which includes wire clamps, connecting fittings and composite insulators. The wire clip, the connecting fittings and the composite insulator form a suspension string group, and the top and bottom ends of the suspension string group are respectively fixed at the crossing points of the two lines. This method breaks through the traditional crossing method, and realizes the drill-through of low-voltage grade lines by reducing the air gap between high-voltage grade overhead lines and drill-through lines. This method breaks through the traditional cross-drilling method, and for the first time proposes the method of using insulating spacer rods to clamp between cross-drilling lines. The safety distance spacer is simple in structure, strong in practicability, greatly saves investment, is easy to realize, and is convenient for construction.

Description

A method for cross-drilling of high-voltage overhead lines and a safety distance interval device

technical field

The invention relates to the technical field of high-voltage overhead lines, in particular to a method for realizing cross-drilling of high-voltage overhead lines and a safety distance spacing device.

Background technique

With the development of the power grid, there are more and more substations, the line corridors are becoming more and more dense, and the probability of cross drilling between overhead lines is increasing. The original design of the high-voltage overhead line only considered the distance between the conductor and the ground with a certain margin in the case of the maximum sag calculation. However, when there is a newly-built line with a lower voltage level than the high-voltage overhead line, it is necessary to drill through the overhead line. During the line, due to the insufficient height, it is necessary to increase the height of the high-voltage line tower or use cable drilling. In this way, the construction is difficult and the investment is high. Especially when cables are used, the later operation and maintenance costs are very high. The cable section is the weak link in the entire transmission line, and the overload capacity is weak. The cable failure is often irrecoverable due to the damage of the cable head. Permanent faults require professional teams and corresponding spare parts and spare parts to be replaced and installed again. It is difficult to repair and the power outage takes a long time. For areas with long operation and maintenance distances, the transportation of spare parts and spare parts is inconvenient, and it is more difficult for professional maintenance teams to rush to repair, which has a greater impact on the operation of the power grid itself.

Contents of the invention

In order to overcome the problems existing in the prior art, the present invention provides a new method for realizing cross-drilling of high-voltage overhead lines. This method can save investment costs, on the one hand, avoid the heightening and transformation of high-voltage line towers, and on the other hand, avoid the galloping of the wires in the event of strong winds, resulting in tripping due to the discharge of the upper wire to the lower wire.

The technical solution adopted by the present invention to solve the technical problem is: the method for cross-drilling high-voltage overhead lines, which is characterized in that: the high-voltage overhead lines include a first-stage high-voltage overhead line and a second-stage high-voltage overhead line, wherein The voltage of the first-level high-voltage overhead line is lower than that of the second-level high-voltage overhead line; the first-level high-voltage overhead line crosses the second-level high-voltage overhead line at a certain angle from under the second-level high-voltage overhead line, and then drills through the second-level high-voltage Overhead lines; the first-level high-voltage overhead lines and the second-level high-voltage overhead lines have several intersections viewed from directly above the second-level high-voltage overhead lines, and each intersection is between the first-level high-voltage overhead lines and the second-level high-voltage overhead lines There are respectively corresponding intersections on the overhead lines; a safety distance spacer is provided between the corresponding intersections on the first-level high-voltage overhead lines and the second-level high-voltage overhead lines; one end of the safety distance spacer is fixed At an intersection of the first-level high-voltage overhead lines, the other end of the safety distance spacer is fixed at the intersection corresponding to the intersection of the first high-voltage overhead lines.

Further, the first-stage high-voltage overhead line is a single-circuit overhead line with a voltage of 35kV, and the second-stage high-voltage overhead line is a double-circuit overhead line with a voltage of 110kV.

Further, the single-circuit overhead line of the first-level high-voltage overhead line and the double-circuit overhead line of the second-level high-voltage overhead line have six intersection points in space, and the six intersection points correspond to the first-level high-voltage overhead line and the double-circuit overhead line respectively. Junction D and Junction D', Junction E and Junction E', Junction F and Junction F', Junction M and Junction M', Junction H and Junction H on second-level high-voltage overhead lines H', Intersection N and Intersection N'.

Further, the drilled section of the first-level high-voltage overhead line does not retain the overhead ground wire.

A safety distance spacing device for cross-drilling of high-voltage overhead lines, characterized in that: it includes a wire clip, connecting fittings and a composite insulator; there are two wire clips, namely the first wire clip and the second wire clip, and the There are two connecting metal fittings, which are respectively the first connecting fitting and the second connecting fitting, and the insulator is a composite insulating spacer; the first clamp is hinged to the first connecting fitting, and the first connecting fitting is connected to one end of the insulating spacer Hinged connection, the other end of the insulating spacer is hingedly connected to the second connecting hardware, and the second connecting hardware is hingedly connected to the second clamp.

Further, the first wire clamp and the second wire clamp are suspension wire clamps, and the first wire clamp, the first connecting hardware, the composite insulator, the second connecting hardware and the second wire clamp are sequentially connected to form a suspension string.

Further, the first wire clamp is connected to the first connecting hardware, and the second wire clamp is connected to the second connecting hardware through pin shafts.

Further, the first wire clamp of one of the safety distance spacing devices is fixedly clamped at the intersection D of the first-level high-voltage overhead line, and the second wire clamp is fixedly clamped at the intersection D of the second-level high-voltage overhead line '; the first clamps of the other five safety distance spacers are respectively fixed at intersection E, intersection F, intersection M, intersection H and intersection N, and the second clamps are respectively fixed at intersection E', intersection At point F', intersection point M', intersection point H' and intersection point N'.

In summary, the beneficial effects of the above-mentioned technical solution of the present invention are as follows: by reducing the air gap between the high-voltage level overhead line, that is, the second-level high-voltage overhead line and the drill-through line, that is, the first-level high-voltage overhead line (only need to meet different The minimum safety net distance between the unobstructed live parts that are not under maintenance at the same time as the crossing of the line is enough) to realize the drilling of low-voltage overhead lines. Compared with the traditional drilling method of increasing the height of the tower, the height of the tower to be drilled over the overhead line (the wire hanging point at the lowest point of the tower) is much lower, and the drilling can be realized without heightening the tower. cross.

Through the first line clamp, connecting fittings and insulators of the safety distance spacer, the upper and lower crossing high-voltage overhead lines are connected together at the intersection point, and the low-voltage level high-voltage overhead line pairs are realized without adding high-voltage level overhead line towers. Successful drilling and clamping of overhead lines with high voltage ratings. It ensures that the upper and lower high-voltage overhead lines are always at a fixed safe distance, and at the same time ensures that the ground distance of low-voltage overhead lines meets the requirements of regulations. This method breaks through the traditional cross-drilling method, has a simple structure, strong practicability, greatly saves investment, is convenient for construction, and achieves good field use results.

Description of drawings

Fig. 1 is the cross-drilling schematic diagram of high-voltage overhead line of the present invention;

Fig. 2 is the safe distance interval device adopted by the present invention.

In the picture:

1 first-level high-voltage overhead line, 2 second-level high-voltage overhead line, 31 first clamp, 32 first connecting fitting, 33 insulating spacer, 34 second connecting fitting, 35 second clamp.

Detailed ways

The features and principles of the present invention will be described in detail below with reference to FIG. 1 and FIG. 2 , and the examples given are only used to explain the present invention, not to limit the protection scope of the present invention.

As shown in Figure 1, a high-voltage overhead line is erected between two adjacent high-voltage towers. Generally, the height of the towers is relatively high to meet the safety height requirements of the high-voltage overhead line. The high-voltage overhead lines between adjacent towers of high-voltage overhead lines of the same voltage have a certain sag under the action of the line's own gravity. The high-voltage overhead lines of different voltages cross each other, and when viewed from the top of the high-voltage overhead lines, several intersections are formed between the high-voltage overhead lines of different voltages.

Among the high-voltage overhead lines cross-drilled, the upper high-voltage overhead line is the first-level high-voltage overhead line 1, and the first-level high-voltage overhead line is a single-circuit overhead line; the lower high-voltage overhead line is the second-level high-voltage overhead line 2 , where the second-level high-voltage overhead line is a double-circuit overhead line. In addition, the voltage level of the first-level high-voltage overhead line 1 is a low-voltage level high-voltage overhead line, and the voltage level of the second-level high-voltage overhead line 2 is a high-voltage level high-voltage overhead line, that is, the voltage of the first level high-voltage overhead line 1 is lower than that of the second level. The voltage of the secondary high-voltage overhead line 2 is described below by taking the voltage of the first-level high-voltage overhead line 1 as 35kV and the voltage of the second-level high-voltage overhead line 2 as 110kV as an example.

A safety distance spacer is provided at the intersection of the high-voltage overhead lines. The top of the safety distance spacer is fixedly connected to the first-level high-voltage overhead line 1 , and the bottom is fixedly connected to the second-level high-voltage overhead line 2 .

As shown in Figure 1, the single-circuit overhead line of the first-level high-voltage overhead line and the double-circuit overhead line of the second-level high-voltage overhead line have six intersection points in space, and the six intersection points correspond to the first-level high-voltage overhead line and the double-circuit overhead line respectively. There are corresponding intersections on the second-level high-voltage overhead lines. Define six intersections corresponding to intersection D and intersection D', intersection E and intersection E', intersection F and intersection F' on the first-level high-voltage overhead line and the second-level high-voltage overhead line, Intersection M and intersection M', intersection H and intersection H', intersection N and intersection N'.

Further, the overhead ground wire of the first-level high-voltage overhead line drilling section (the part of the first-level high-voltage overhead line that is close to the intersection point with the second-level high-voltage overhead line) is not retained, that is, the first-level high-voltage overhead line is drilled through. When the second-level high-voltage overhead line is used, the ground wire of the second-level high-voltage overhead line can be used to achieve lightning protection through calculation, thereby further reducing the limit of the drilling height.

As shown in FIG. 2 , the safety distance spacing device includes a wire clip 31 , connecting hardware and an insulator 33 . There are two wire clips, and the structures of the two wire clips are identical, namely the first wire clip 31 and the second wire clip 34 . There are also two connecting fittings, and the structures of the two connecting fittings are also identical, namely the first connecting fitting 32 and the second connecting fitting 35 . The composite insulator is an insulating spacer, and the insulating spacer is connected with the fittings to form a string. The first wire clip 31 is hinged and movably connected with the first connecting hardware 32 . The first connecting fitting 32 is hinged and movably connected to one end of the insulating spacer. The other end of the insulating spacer is hinged and movably connected with the second connecting hardware 34 . The second connecting hardware 34 is hinged and movable with the second wire clamp 35 .

Further, the first wire clamp 31 and the first connecting hardware 32, and the second wire clamp 35 and the second connecting hardware 34 may be connected by pin shafts. The first wire clamp 31 and the first connecting fitting 32, the second wire clamp 35 and the second connecting fitting 34 can be rotated freely, which increases the flexibility of the safety distance spacing device. The first line clamp 31 is clamped and fixed on the first-level high-voltage overhead line 1 , and the second line clamp 35 is clamped and fixed on the second-level high-voltage overhead line 2 . According to the requirement of the minimum safe clear distance between the first-level high-voltage overhead line 1 and the second-level high-voltage overhead line 2, the length of the insulating spacer can be adjusted appropriately.

Further, the first wire clamp 31 and the second wire clamp 35 can be selected as the suspension wire clamp, and the first wire clamp 31, the first connecting fitting 32, the insulating spacer, the second connecting fitting 34 and the second wire clamp 35 are sequentially connected to form a suspension string group.

Further, the single-circuit overhead line of the first-level high-voltage overhead line 1 and the double-circuit line of the second-level high-voltage overhead line 2 have six intersection points in space, and the six intersection points correspond to the first-level high-voltage overhead line respectively. 1 and the intersection D and D', the intersection E and E', the intersection F and F', the intersection M and M', the intersection H on the second level high-voltage overhead line and the intersection H', the intersection N and the intersection N'; the first line clip in one of the safety distance spacers is clamped and fixed at the intersection D, and the safety distance spacer is placed naturally drooping, and the second line clip Clamped and fixed at the intersection D', the first clamps of the other five safety distance spacers are respectively fixed at the intersection E, intersection F, intersection M, intersection H and intersection N, and the second clamps are respectively Fix at intersection E', intersection F', intersection M', intersection H' and intersection N'.

Need to borrow special-purpose ladder during concrete operation, at first the first line clamp 31 is clamped on the first level high voltage overhead line 1, the first connecting fitting 32, insulating spacer bar, the second connecting fitting 34 and the second line clamp 35 are under gravity Naturally droop under action. Then use a hook or other lifting tools to raise the second-level high-voltage overhead line 2 to the position where the second clamp 35 naturally hangs down, and clamp and fix the second clamp 35 on the second-level high-voltage overhead line 2 . Then install other safety distance spacers in sequence.

It is also possible to clamp and fix the first line clamps 31 of all safety distance spacers on the first-level high-voltage overhead line 1, and then clamp and fix the second line clamp 35 on the second-level high-voltage overhead line 2 in the above-mentioned manner. .

The safety distance interval device and its installation method are also applicable to high-voltage overhead lines of other voltage levels and other lines with cross-drilling lines. According to the requirements of the minimum safe clear distance between high-voltage overhead lines of different voltages, the length of the insulating spacer can be adjusted.

The high-voltage overhead lines intersecting up and down are connected together by the first wire clamp, connecting fittings and insulating spacer of the safety distance spacer, and the overhead line has been successfully drilled without adding high-voltage overhead line towers. This method breaks through the traditional cross-drilling method, and for the first time proposes the method of using insulating spacer rods to clamp between cross-drilling lines. The structure is simple, the practicability is strong, the investment is greatly saved, the realization is easy, and the construction is convenient.

The above-mentioned embodiments are only descriptions of preferred implementations of the present invention, and are not intended to limit the scope of the present invention. On the premise of not departing from the design spirit of the present invention, those skilled in the art should make various modifications and improvements of the present invention. Into the scope of protection defined by the claims of the present invention.

Claims (8)

1. A method for cross drilling of high-voltage overhead lines, characterized in that: said high-voltage overhead lines comprise first-level high-voltage overhead lines and second-level high-voltage overhead lines, wherein the voltage ratio of the first-level high-voltage overhead lines is higher than the second The voltage of the first-level high-voltage overhead line is low; the first-level high-voltage overhead line crosses the second-level high-voltage overhead line at a certain angle from the bottom of the second-level high-voltage overhead line, and then drills through the second-level high-voltage overhead line; the first-level high-voltage overhead line There are several intersections between the line and the second-level high-voltage overhead line viewed directly above the second-level high-voltage overhead line, and each intersection has a corresponding intersection on the first-level high-voltage overhead line and the second-level high-voltage overhead line ;A safety distance spacer is provided between the corresponding intersections of the first-level high-voltage overhead line and the second-level high-voltage overhead line; one end of the safety distance spacer is fixed at an intersection of the first-level high-voltage overhead line , the other end of the safety distance spacer is fixed on the intersection point corresponding to the intersection point of the first high-voltage overhead line. 2. A method for cross drilling of high-voltage overhead lines according to claim 1, characterized in that: the first-stage high-voltage overhead lines are single-circuit overhead lines with a voltage of 35kV, and the second-stage high-voltage overhead lines are Double-circuit overhead lines with a voltage of 110kV. 3. A method for cross-drilling high-voltage overhead lines according to claim 2, characterized in that: the single-circuit overhead line of the first-level high-voltage overhead line and the double-circuit overhead line of the second-level high-voltage overhead line There are six intersections in the space, and the six intersections correspond to intersection D and intersection D', intersection E and intersection E', and intersection F on the first-level high-voltage overhead line and the second-level high-voltage overhead line respectively. and intersection F', intersection M and intersection M', intersection H and intersection H', intersection N and intersection N'. 4. A method for cross-drilling high-voltage overhead lines according to claim 1, wherein the overhead ground wire is not reserved in the first-stage high-voltage overhead line drilling section. 5. A safety distance spacing device for cross-drilling of high-voltage overhead lines, characterized in that: it includes wire clips, connecting fittings and composite insulators; there are two wire clips, which are respectively the first wire clip and the second wire clip, There are two connecting fittings, namely the first connecting fitting and the second connecting fitting, and the insulator is a composite insulating spacer; the first clamp is hinged to the first connecting fitting, and the first connecting fitting is connected to the insulating spacer One end of the insulating spacer is hingedly connected, the other end of the insulating spacer is hingedly connected to the second connecting hardware, and the second connecting hardware is hingedly connected to the second clamp. 6. A safety distance spacing device for cross-drilling of high-voltage overhead lines according to claim 5, characterized in that: the first wire clip and the second wire clip are suspension wire clips, the first wire clip, the first wire clip The connecting fittings, the composite insulators, the second connecting fittings and the second clamp are sequentially connected to form a suspension string. 7. A safety distance spacing device for cross-drilling of high-voltage overhead lines according to claim 5, characterized in that: the first wire clamp and the first connecting hardware, the second wire clamp and the second connecting hardware pass through pins shaft connection. 8. A safety distance spacing device for cross-drilling of high-voltage overhead lines according to claim 5, characterized in that: the first wire clamp of one of the safety distance spacing devices is fixed and clamped on the first-stage high-voltage overhead line At the intersection point D of the line, the second line clamp is fixed and clamped at the intersection point D' of the second-level high-voltage overhead line; the first line clamps of the other five safety distance devices are respectively fixed at the intersection point E, intersection point F, and intersection point At the point M, the point H and the point N, the second clamps are respectively fixed at the point E', the point F', the point M', the point H' and the point N'.