WO2017036274A1

WO2017036274A1 - Single-row valve tower of high-voltage dc transmission converter valve

Info

Publication number: WO2017036274A1
Application number: PCT/CN2016/093907
Authority: WO
Inventors: 高冲; 杨俊�; 魏晓光; 刘杰
Original assignee: 全球能源互联网研究院; 国家电网公司; 国网浙江省电力公司
Priority date: 2015-09-02
Filing date: 2016-08-08
Publication date: 2017-03-09
Also published as: CN105207498B; CN105207498A

Abstract

A single-row valve tower of a high-voltage DC transmission converter valve comprises horizontally-arranged top and bottom shielding covers (1) and (6), and a converter valve arranged between the top shielding cover (1) and the bottom shielding cover (6). The converter valve is connected with the top shielding cover (1) and the bottom shielding cover (6) through suspension insulators (12). The converter valve is formed in such a manner that converter valve modules (3), which form an angle of inclination with respect to a horizontal direction, are orderly connected in series in a vertical direction in the form of a zigzag rule. Having a more compact overall structure and a more reasonable layout, the high-voltage DC transmission converter valve single-row valve tower well solves the problem of high-frequency oscillation resulting from insulation of a cooling water path and connecting busbar inductance, reduces the operational risk, and conforms to the design requirements of (ultra) high-voltage DC transmission converter valves with higher voltage and current levels.

Description

Single-column valve tower for high-voltage direct current transmission converter valve

Technical field

The invention relates to a valve tower, in particular to a folding single-row valve tower of a high-voltage direct current transmission converter valve.

Background technique

The continuous increase in the demand for electric energy in modern social and economic activities has promoted the continuous evolution of the structure and scale of the power system. At present, in order to adapt to the high concentration of power load, energy distribution, and shortage of energy resources in large-load areas, and to meet the requirements of environmental protection, large-scale clean energy centralized development and long-distance transportation have gradually become the mainstream energy development and utilization methods. HVDC transmission technology is widely used due to its economic advantages in long-distance transmission of electric energy and the technical advantages of enhancing grid stability.

The HVDC converter valve is the core equipment of the HVDC transmission system and is the key to ensure the reliable operation of the system. Due to the continuous improvement of the transmission capacity of the HVDC transmission line, the maximum rated DC voltage and DC current of the DC transmission converter valve are 1100kV and 6250A, respectively. The large increase in voltage and current has brought great challenges to the design of DC transmission converter valves, among which the design of the converter valve is particularly prominent.

The structural design of the converter valve is based on electrical design. It is necessary to consider the overvoltage insulation coordination between components, reliable mechanical strength, good heat dissipation and rational layout of key components, and operability of electrical wiring between components. And reliability, while considering fire protection design and EMC requirements.

At present, HVDC (High-Voltage Direct Current) converter valves mostly use water-cooled, air-insulated, suspended modular structure, and the valve tower structure is more and more compact due to the expensive cost of the converter valve hall. Figure 1 and Figure 2 show the two types of structures, single-row valve tower and double-row valve tower, which are commonly used in current DC transmission projects.

Whether it is a single-row valve tower or a double-row valve tower, some electrical and structural problems will become more prominent as voltage and current increase. First, the voltage increase requires that the pressure resistance of the converter valve increases, the number of series components of the converter valve increases, the size of the converter valve module and the insulation distance between the valve tower layers increase, and objectively requires commutation. The appearance of the valve is increasing, but the cost of the valve chamber is becoming more and more expensive. It is necessary to require the design of the converter valve to improve the space utilization. It is as compact as possible to meet the insulation requirements of the converter valve to reduce the valve. The proportion of the office area. Second, the main water pipe between the layers of the converter valve is connected between the two layers of the valve tower, and the two ends of the converter are to withstand the interlayer voltage of the converter valve. The voltage increase will cause the leakage current in the interlayer water pipe to increase, and the influence layer The static distribution of the voltage creates electrical corrosion in the metal joint portion of the water pipe, which reduces the reliability and life of the valve tower. Third, the shunt valve shielding system's capacitive shunting results in uneven voltage distribution between the converter valve layers, and the increase in valve tower size and series number increases the degree of non-uniformity. For the valve module of a single-row valve tower, the voltage equalization capacitor must be connected in parallel to balance the voltage distribution. However, since the interlayer busbar functioning as an electrical connection in the valve tower of the converter valve has a certain inductance, under the action of a high-frequency surge voltage such as a lightning wave, high-frequency oscillation occurs between the voltage-inductance of the part of the inductor and the component. This causes high-frequency oscillating voltage to be generated across the thyristor element in the converter valve, as shown in Figure 3. The peak value of the oscillating voltage and the high rate of voltage change are very unfavorable for the thyristor. In severe cases, the thyristors can be destroyed and the converter station is shut down. Therefore, special measures must be taken to avoid oscillations.

Summary of the invention

In order to solve the above-mentioned deficiencies in the prior art, embodiments of the present invention provide a single-column valve tower for a high-voltage direct current transmission converter valve.

The technical solution provided by the embodiment of the present invention is: a single-column valve tower of a high-voltage direct current transmission converter valve, comprising a horizontally disposed top shield cover, a bottom shield cover, and a bottom shield cover disposed between the top shield cover and the bottom shield cover a converter valve, the converter valve being connected to the top shield and the bottom shield by a suspension insulator, the converter valve being folded in a vertical direction by a converter valve module inclined at an angle to a horizontal direction The form of the ruler is connected in series.

As an embodiment, the converter valve module includes a stabilizing frame and a branch water pipe, a main water pipe, a trigger plate, a thyristor (TCA), a damping capacitor, a damping resistor, and a saturable reactor installed in the stabilizing frame.

As an embodiment, the stabilizing frame includes two insulating groove beams parallel to each other and a metal groove beam vertically disposed between the two insulating groove beams; the insulating groove beam is provided with a through hole penetrating through the metal, the metal The two ends of the channel beam respectively have mounting holes corresponding to the through holes, and the metal channel beams are fixed to the insulating channel beams by bolts penetrating the mounting holes and the through holes.

As an embodiment, the saturable reactor is symmetrically installed between the metal channel beams on the inner side of the two ends of the stabilizing frame; two saturated reactors are disposed at each end, and each of the saturated reactors is respectively fixed to the two metal slots by bolts On the beam, the other side is provided with an end busbar;

A damping capacitor, a damping resistor, a branch water pipe, a thyristor (TCA) and a trigger plate parallel to the insulating channel beam are disposed in sequence from one side to the other side in a direction perpendicular to the insulating channel beam between the two ends of the saturable reactor; The damper capacitor, the damper resistor, the thyristor (TCA) and the two ends of the trigger plate are respectively fixed on the metal channel beam by bolts; the two ends of the branch water pipe are respectively fixed to the metal channel beam through the flange tube on;

The flanges of the two metal channel beams between the insulating channel beams are respectively welded to the plane perpendicular to the plane of the metal channel beam and the insulating channel beam, and the side wall of the flange tube is reserved for communication The through hole of the branch water pipe, the two ends of the branch water pipe are respectively connected with the flange pipe on the two metal groove beams.

As an embodiment, two upper and lower adjacent converter valve modules are connected at a short end through a main water pipe and an interlayer bus bar;

The main water pipe is a hose, and two ends of the main water pipe are respectively provided with a metal flange, and the two ends of the main water pipe are respectively connected with the flange pipes of the upper and lower two converter valve modules through a metal flange;

The two ends of the interlayer busbar are electrically connected to the end busbars of the upper and lower two converter valve modules, respectively.

As an embodiment, a vertical square is also arranged between the upper and lower two adjacent converter valve modules. The interlayer insulators are respectively provided with metal hangers on both sides of the interlayer insulators, and the metal hangers at both ends of the interlayer insulators are respectively connected to the metal channel beams of the upper and lower two converter valve modules through the connecting members.

As an embodiment, the top shield and the bottom shield are each a rectangular parallelepiped shape, and an insulator support structure is longitudinally disposed in the shield, the insulator support structure includes two longitudinal angles parallel to each other and vertical welding. A transverse angle steel between two longitudinal angles, the longitudinal angle steel is also welded with a support angle perpendicular to the plane of the longitudinal angle steel and the transverse angle steel, and the other end of the support angle steel is welded in the shield.

As an embodiment, the top shield and the bottom shield are respectively connected to the converter valve modules at the upper and lower ends by a suspension insulator;

The two ends of the suspension insulator are respectively provided with metal hangers, and the suspension insulators connecting the top shield cover and the upper converter valve module respectively pass through the metal hangers at both ends thereof and the transverse and longitudinal angles in the top shield respectively. Connected to the metal channel beam of the upper converter valve module;

The suspended insulator connecting the bottom shield and the lower converter valve module is respectively connected to the horizontal and vertical angle steels in the bottom shield and the metal channel beam of the lower end converter valve module through the metal hangers at both ends thereof.

In one embodiment, the upper-end converter valve module is connected to the top shield through an interlayer busbar and a main water pipe at a short-distance end, and one end of the interlayer busbar is electrically connected to the upper-end converter valve module. The other end is electrically connected to the top shield; the main water pipe is overlapped in the top shield by a fixing member, one end of which is connected to the flange tube of the upper end converter valve module, and the other end is connected The top shield is led out and connected to the external water cooling system;

The lower-end converter valve module is connected to the bottom shield through the interlayer busbar and the main water pipe at a short-distance end, and one end of the interlayer busbar is electrically connected to the end busbar of the lower-end converter valve module, and One end is electrically connected to the bottom shield; the main water pipe is overlapped in the bottom shield by a fixing member, one end of which is connected to the flange tube of the lower end converter valve module, and the other end is connected through the bottom shield cover and then connected External water cooling system.

As an embodiment, the angle of inclination of the converter valve module with respect to the horizontal direction is 7 degrees to 10 degrees.

Embodiments of the present invention have significant advancements as compared to the closest prior art:

(1) The high-voltage DC converter valve module is arranged at an angle to the horizontal plane, and the near-end of the layer is electrically and water-circuited. The structure of the valve tower is more compact and compact, which effectively improves the space utilization of the converter valve and helps to save the valve hall. Land occupation cost;

(2) The water flow of the converter valve is consistent with the potential distribution of the electric part to achieve natural pressure equalization. There is no potential difference between the two ends of the main water pipe, no leakage current, eliminating the static static pressure between the layers caused by the water leakage current and the metal joint of the waterway. Adverse effects such as corrosion;

(3) The length of the busbar between the layers is greatly reduced, which greatly reduces the stray inductance of the busbar between the layers. Under the high-frequency surge voltage such as lightning, the high-frequency oscillation between the voltage-dividing capacitor of the component and the busbar between the layers is no longer Occurs to protect the converter valve thyristor components from oscillating voltage spikes and high voltage rate of change.

DRAWINGS

1 is a schematic structural view of a conventional single-column valve tower of a high-voltage direct current transmission converter valve;

2 is a schematic structural view of a conventional double-column valve tower of a high-voltage direct current transmission converter valve;

Figure 3 is a transformation diagram of the voltage across the thyristor element in the converter valve under the applied surge voltage of the existing single-row valve tower;

4 is a schematic structural view of a single-row valve tower of a high-voltage direct current power transmission converter valve according to an embodiment of the present invention;

Figure 5 is a perspective view of the shield of Figure 4;

Figure 6 is a perspective view of the converter valve module of Figure 4.

Wherein 1-top shield; 2-layer insulator; 3-flow valve module; 4-main water pipe; 5-layer busbar; 6-bottom shield; 7-metal hanger; 8-support angle steel; - Shield; 10 - transverse angle steel; 11 - longitudinal angle steel; 12 - suspended insulator; 13 - saturated reactor; 14 - end busbar; 15 - damping capacitor; 16 - branch water pipe; 17 - damping resistance; - metal channel beam; 19-thyristor TCA; 20-trigger board; 21-insulated channel beam; 22-flange tube; 23-shield.

detailed description

In order to better understand the present invention, the contents of the present invention are further described below in conjunction with the drawings and examples.

The single-column valve tower of the high-voltage direct current transmission converter valve provided by the embodiment of the present invention is as shown in FIG. 4, and is mainly composed of a top shield cover 1, a bottom shield cover 6, a converter valve module 3, a main water pipe 4, an interlayer busbar 5, and a layer. The insulator 2 and the suspended insulator 12 are composed.

The top shield 1 and the bottom shield 6 function as a uniform electric field distribution and anti-electromagnetic interference, and the top shield 1 and the bottom shield 6 and the converter valve module 3 are connected by a suspension insulator 12, suspended The metal hanger 7 at both ends of the insulator 12 is a coupling member. As shown in FIG. 5, the shield cover 9 has a rectangular parallelepiped shape as a whole. The sides and corners of the rectangular shield 9 are polished and arc-transformed, and the shield 9 is longitudinally disposed. An insulator support structure is provided. The insulator support structure comprises two parallel longitudinal angles 11 and a transverse angle 10 vertically welded between the two longitudinal angles 11. Further, the longitudinal angle 11 is welded to the longitudinal angle 11 and the transverse direction. The supporting angle 8 of the plane of the angle steel 10, the other end of the supporting angle 8 is welded in the shield 9; in order to fix the insulator supporting structure and the suspended insulator 12, the transverse angle steel 10 and the longitudinal angle steel 11 of the insulator supporting structure are arranged Through holes, in particular, transverse angle steel 10 at the four corners of the insulator support structure and through holes are formed in the longitudinal angle steel 11,

A metal hanger 7 is respectively disposed at two ends of the suspension insulator 12, and a through hole is also disposed on the metal hanger 7 at both ends, and the metal hanger 7 at one end of the suspension insulator 12 is attached to the insulator support structure to make the metal hanger The through hole on the seat 7 corresponds to the through hole of the insulator supporting structure, and is fixedly connected to the insulator supporting structure through a bolt penetrating the through hole.

The converter valve module 3 is the core part of the converter valve, and its structure is as shown in FIG. 6, which mainly includes the branch water pipe 16, the main water pipe 4, the trigger plate 20, the thyristor (TCA) 19, the damping capacitor 15, the damping resistor 17 and Saturated reactor 13, all devices are mounted on metal channel beams 18 and insulated channel beams In the stabilizing frame formed by the 21, a shield cover 23 is disposed around the periphery of the stabilizing frame for ensuring the shielding effect on the electric field of the converter valve module 3.

The stabilizing frame is composed of two insulating groove beams 21 parallel to each other and a metal groove beam 18 vertically disposed between the two insulating groove beams 21. The insulating groove beam 21 is provided with a transverse through hole, a metal groove beam Each of the two ends of the 18 has a mounting hole corresponding to the through hole, and the two ends of the metal groove beam 18 respectively fit the inner sides of the two insulating groove beams 21, and the mounting holes correspond to the through holes on the insulating groove beam 21, The metal channel beam 18 is fixed between the insulating channel beams 21 by bolts penetrating the mounting holes and the through holes.

The saturable reactors 13 are symmetrically mounted between the metal channel beams 18 on the inner sides of the two ends of the stabilizing frame; two saturated reactors 13 are disposed at each end, and each of the saturated reactors 13 is respectively fixed to the two metal channel beams by bolts. On the other side, an end busbar 14 is provided.

A damping capacitor 15 parallel to the insulating channel beam 21, a damping resistor 17, a branch water pipe 16, and a thyristor TCA 19 are fixed in order from the one side to the other side in a direction perpendicular to the insulating groove beam 21 between the both ends of the saturated reactor 13 And the trigger plate 20; wherein the two ends of the damping capacitor 15, the damping resistor 17, the thyristor TCA 19 and the trigger plate 20 are respectively fixed to the metal channel beam 18 by bolts.

Two of the metal channel beams 18 between the insulating channel beams 21 are respectively fixed with flange tubes 22 perpendicular to the plane of the metal channel beams 18 and the insulating channel beams 21, and the side walls of the flange tubes 22 are provided with connecting branches. The through holes of the water pipe 16 and the two ends of the branch water pipe 16 are respectively connected to the two flange pipes 22.

The main water pipe 4 is a hose, and two ends thereof are respectively provided with a metal flange for connecting the branch water pipe 16 of the upper and lower adjacent converter valve modules 3, and the flange of the main water pipe 4 and the converter valve module 3 The flange tube 22 is connected at one end, and the flange at the other end is connected to one end of the flange tube 22 of the other converter valve module 3.

One end of the interlayer busbar 5 is connected to the end busbar 14 of the saturation reactor 13 at one end of the converter valve module 3, and the other end is connected to the end busbar 14 of the saturated reactor 13 at the end of the other converter valve module 3.

The converter valve module 3 is inclined at an angle to the horizontal plane (for example, 7°-10°), according to the layer The distance between the long distance ends is continuously adjusted; the upper and lower adjacent converter valve modules 3 are connected at the close end through the main water pipe 4 and the interlayer busbar 5, so that the converter valve is folded like a folding ruler as a whole. . In this arrangement, the adjacent two ends of the converter valve tower are equipotential ends, and the design value of the clearance is small, which effectively reduces the height of the valve tower, and the inclined valve module 3 is tilted to lower the valve tower. The projected area effectively improves the space utilization of the converter valve tower; at the same time, the water circuit voltage distribution is consistent with the main circuit voltage distribution, realizing the natural pressure equalization of the waterway, and the potentials at both ends of the main water pipe 4 are consistent, and there is no creepage ratio requirement. And the leakage current problem; in addition, due to the small distance between the layers at the close end, the length of the inter-layer connection busbar is greatly shortened, and the inductance value is reduced to negligible, thereby fundamentally eliminating the possibility of high-frequency oscillation. .

The suspension load between the converter valve modules 3 is realized by the interlayer insulators 2. The two ends of the interlayer insulators 2 are respectively provided with metal hangers 7, and the metal hangers 7 at the two ends are respectively connected with the upper and lower converter valve modules. The metal channel beams 18 of 3 are connected by bolts.

The short-distance end busbars 14 of the single-row valve bottom converter valve module 3 are electrically connected to the bottom shield 6 via the interlayer busbar 5. The proximal end flange tube 22 of the bottom end converter valve module 3 is connected to one end of the main water pipe 4, the main water pipe 4 is fixed in the bottom shield cover 6 through a mounting member, and the other end of the main water pipe 4 is connected to the water cooling system;

The close end end busbar 14 of the single row valve top end converter valve module 3 is electrically connected to the top shield 1 by an inter-layer busbar 5. The proximal end flange tube 22 of the top converter valve module 3 is connected to one end of the main water pipe 4, and the main water pipe 4 is fixed in the top shield 1 by a mounting member, and the other end of the main water pipe 4 is connected to the water cooling system.

In order to satisfy the folding connection between the converter valve modules 3, only one-way branch water pipe 16 is provided inside the converter valve module 3, and the cooling water supplied from the water cooling system enters the valve from the main water pipe 4 of the bottom converter valve module 3 The tower is cooled again by flowing back to the water cooling system through the main water pipe 4 of the top of the valve valve module 3 of the valve tower.

The above are only the embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are made within the spirit and principles of the present invention, are included in the application. It is within the scope of the appended claims.

Industrial applicability

The technical scheme of the embodiment of the invention makes the overall structure of the single-row valve tower of the high-voltage direct current transmission converter valve more compact and the layout is more reasonable by adopting the novel valve tower structure, and better solves the high frequency caused by the insulation of the cooling water channel and the inductance of the coupled busbar. Oscillation problem, reduce operational risk, meet the design requirements of (special) HVDC converter valve with higher voltage and current levels.

Claims

A single-column valve tower of a high-voltage direct current transmission converter valve includes a horizontally disposed top shield, a bottom shield, and a converter valve disposed between the top shield and the bottom shield, the converter valve passing The suspension insulator is connected to the top shield and the bottom shield, and the converter valve is formed by connecting the converter valve modules at an oblique angle to the horizontal direction in a vertical direction in the form of a folding rule.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 1, wherein:

The converter valve module includes a stabilizing frame and a branch water pipe, a main water pipe, a trigger plate, a thyristor TCA, a damping capacitor, a damping resistor, and a saturable reactor installed in the stabilizing frame.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 2, wherein:

The stabilizing frame comprises two insulated trough beams parallel to each other and a metal trough beam vertically disposed between the two insulating trough beams; the insulating trough beam is provided with a transverse through hole, and the two ends of the metal trough beam respectively a mounting hole corresponding to the through hole, the metal channel beam being fixed to the insulating groove beam by a bolt penetrating the mounting hole and the through hole.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 3, wherein:

The saturable reactor is symmetrically installed between the metal channel beams on the inner side of the two ends of the stabilizing frame; two saturated reactors are arranged at each end, and each of the two sides of the saturable reactor is respectively fixed on the two metal channel beams by bolts, and the other The side is provided with an end busbar;

a damping capacitor, a damping resistor, a branch water pipe, a thyristor TCA and a trigger plate parallel to the insulating channel beam are disposed in order from the one side to the other side in a direction perpendicular to the insulating channel beam between the two ends of the saturable reactor; the damping The two ends of the branch water pipe are respectively fixed on the metal channel beam by bolts;

The flanges of the two metal channel beams between the insulating channel beams are respectively welded to the plane perpendicular to the plane of the metal channel beam and the insulating groove beam, and the side walls of the flange tube are left for communication. The through hole of the branch water pipe, the two ends of the branch water pipe are respectively connected with the flange pipe on the two metal groove beams.
A single-column valve tower for a high-voltage direct current transmission converter valve according to any one of claims 1 to 4, wherein:

Two upper and lower adjacent converter valve modules are connected at a short distance through the main water pipe and the interlayer busbar;

The main water pipe is a hose, and two ends of the main water pipe are respectively provided with a metal flange, and the two ends of the main water pipe are respectively connected with the flange pipes of the upper and lower two converter valve modules through a metal flange;

The two ends of the interlayer busbar are electrically connected to the end busbars of the upper and lower two converter valve modules, respectively.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 5, wherein:

A vertical insulator is disposed between the upper and lower adjacent converter valve modules, and two sides of the interlayer insulator are respectively provided with metal hangers, and metal hangers at both ends of the interlayer insulator are respectively connected The piece is connected to the metal channel beam of the upper and lower converter valve modules.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 1, wherein:

The top shield and the bottom shield are each a rectangular parallelepiped shape. The shield cover is longitudinally disposed with an insulator support structure. The insulator support structure includes two longitudinal angles parallel to each other and vertically welded to the two longitudinal angles. The transverse angle steel is welded to the longitudinal angle steel with a support angle perpendicular to the plane of the longitudinal angle steel and the transverse angle steel, and the other end of the support angle steel is welded in the shield.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 7, wherein:

The top shield and the bottom shield are respectively connected to the converter valve modules at the upper and lower ends by a suspension insulator;

The two ends of the suspension insulator are respectively provided with metal hangers, and the suspension insulators connecting the top shield cover and the upper converter valve module respectively pass through the metal hangers at both ends thereof and the transverse and longitudinal angles in the top shield respectively. Connected to the metal channel beam of the upper converter valve module;

Suspended insulator connecting the bottom shield and the lower converter valve module through the metal hanger at both ends They are respectively connected to the horizontal and longitudinal angle steels in the bottom shield and the metal channel beams of the lower end converter valve module.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 8, wherein:

The upper end converter valve module is connected to the top shield through the interlayer busbar and the main water pipe at a short distance end, and one end of the interlayer busbar is electrically connected to the end busbar of the upper end converter valve module, and One end is electrically connected to the top shield; the main water pipe is overlapped in the top shield by a fixing member, one end of which is connected to the flange tube of the upper end converter valve module, and the other end is connected by a top shield cover and then connected External water cooling system;

The lower-end converter valve module is connected to the bottom shield through the interlayer busbar and the main water pipe at a short-distance end, and one end of the interlayer busbar is electrically connected to the end busbar of the lower-end converter valve module, and One end is electrically connected to the bottom shield; the main water pipe is overlapped in the bottom shield by a fixing member, one end of which is connected to the flange tube of the lower end converter valve module, and the other end is connected through the bottom shield cover and then connected External water cooling system.
A single-column valve tower for a high-voltage direct current transmission converter valve according to claim 1, wherein:

The angle of inclination of the converter valve module with respect to the horizontal direction is 7 degrees to 10 degrees.