CN117895803A - Suspension type converter valve tower device and flexible direct current transmission system - Google Patents

Abstract

The invention relates to the technical field of power electronics, in particular to a suspension type converter valve tower device and a flexible direct current transmission system. A suspended converter valve tower apparatus comprising: a valve module layer; the valve module comprises a first suspension type insulating rod, one end of the first suspension type insulating rod is fixedly connected with a valve module layer, the other end of the first suspension type insulating rod is suitable for being fixedly connected with a valve hall roof steel beam so that the valve module layer is in a suspension state, the valve module layer is suitable for keeping the minimum insulation distance with the ground, and vehicles and personnel are maintained on the ground. The invention solves the problems that a ground support type converter valve tower occupies most of the area of a converter valve hall, so that a converter valve tower installation area cannot pass through vehicles and equipment, maintenance vehicles need to repeatedly bypass the converter valve tower in the valve hall during maintenance, and manpower and time are consumed, thereby providing a suspension type converter valve tower device and a flexible direct current transmission system.

Description

Suspension type converter valve tower device and flexible direct current transmission system

Technical Field

The invention relates to the technical field of power electronics, in particular to a suspension type converter valve tower device and a flexible direct current transmission system.

Background

The flexible direct current converter valve is core equipment of flexible direct current transmission, and a plurality of basic functional unit modules are connected in series by means of a modularized multi-level technology, so that conversion and transmission between high-voltage and high-power alternating current and direct current are realized.

The basic functional unit of a converter valve, also called a sub-module, employs a power electronics device with a turn-off function as its core functional unit, such as an IGBT. Because of the relatively low voltage levels experienced by the power electronics in a single sub-module, it is generally necessary to connect several sub-modules in series for use. The number of the series sub-modules of each flexible direct current transmission project is generally hundreds of different according to the rated voltage and the transmission capacity of each flexible direct current transmission project. If each sub-module is installed in series one by one on the engineering site, the workload is very huge. The engineering technician therefore chooses to assemble a smaller number of sub-modules in series in the factory in advance into a unit that is relatively independent both electrically and structurally, and then transport this unit to the engineering site for installation, this independent unit being referred to as a valve module.

The number of the submodules connected in series in the valve module is more than or equal to two, and voltage differences exist among different submodules, so that certain insulation distance between the submodules is ensured. The structural beams used for fixing the plurality of sub-modules in the ground support type valve module need to use insulating beams, such as glass fiber reinforced epoxy resin U-shaped beams; the two ends of the insulating beam are provided with metal beams which, together with the insulating beam, form a rectangular frame structure which provides sufficient strength for the transport and installation of the sub-modules and also to resist the seismic loads which may occur in the site of the project.

The converter valve is installed in the converter valve hall, and the valve module or the submodule cannot be directly tiled on the ground of the valve hall in consideration of the economic factors of occupied land. Engineering technicians have designed a layered structure on the valve hall floor, similar to warehouse racks, into which valve modules are to be installed, and through other auxiliary facilities, the valve modules are connected in series, this layered installation structure being called a supporting converter valve tower. Each flexible direct current transmission project is required to be provided with a plurality of converter valve towers, the converter valve towers are evenly distributed into six converter phase bridge arms, and the converter valve towers in the same phase bridge arm are serially connected through a bus bar.

With the improvement of the voltage class of the flexible direct current transmission engineering, the height of a post insulator required to support a converter valve tower is also continuously increased, and in order to maintain the rigidity and strength of the post insulator, the diameter of a core rod is also rapidly increased, so that the cost of the insulator and the process complexity are extremely rapidly increased. On the other hand, the floor space of the flexible dc converter station is severely limited due to low cost, and in order to install more converter valves per unit area, it is necessary to increase the valve tower height, and at the same time, the shock resistance of the entire structure of the valve tower is raised, which further results in the rise of the valve tower structure cost. The existing ground-supported converter valve tower occupies most of the area of a converter valve hall, and vehicles and equipment cannot pass through the area where the converter valve tower is installed, and various maintenance vehicles need to repeatedly bypass the converter valve tower in the valve hall during maintenance, so that great manpower and time consumption are caused.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defects that the ground-supported converter valve tower occupies most of the area of a converter valve hall in the prior art, so that a converter valve tower installation area cannot pass through vehicles and equipment, maintenance vehicles need to repeatedly bypass the converter valve tower in the valve hall during maintenance, and labor and time are consumed, and therefore, the suspended converter valve tower device and the flexible direct current transmission system are provided.

In order to solve the above problems, the present invention provides a suspended converter valve tower apparatus comprising:

A valve module layer;

the valve module comprises a first suspension type insulating rod, one end of the first suspension type insulating rod is fixedly connected with a valve module layer, the other end of the first suspension type insulating rod is suitable for being fixedly connected with a valve hall roof steel beam so that the valve module layer is in a suspension state, the valve module layer is suitable for keeping the minimum insulation distance with the ground, and vehicles and personnel are maintained on the ground.

Optionally, the valve module layer comprises two valve module assemblies, and the two valve module assemblies are fixedly connected to form the valve module layer.

Optionally, the valve module layer is divided into a first valve module layer, a second valve module layer and a third valve module layer, the first valve module layer is fixedly connected with the first suspension type insulating rod, the first valve module layer is fixedly connected with the second valve module layer through the second suspension type insulating rod, and the second valve module layer is fixedly connected with the third valve module layer through the second suspension type insulating rod.

Optionally, each valve module assembly includes first girder, second girder, third girder, suspension pull rod and a plurality of submodule, first girder and second girder parallel arrangement, first girder and second girder interval set up, each submodule passes through suspension pull rod respectively with first girder, second girder fixed connection, the quantity of third girder is two, one the one end of first girder and second girder is located to the third girder, another the other end of first girder and second girder is located to the third girder, third girder respectively with first girder and second girder fixed connection in order to form the frame.

Optionally, a second suspended insulating rod is arranged between third main beams between valve module assemblies of the adjacent valve module layers.

Optionally, the valve house further comprises two suspension brackets, the two suspension brackets are symmetrically arranged, and each suspension bracket is fixedly connected with the first valve module layer and the valve hall roof steel beam respectively.

Optionally, the cooling assembly comprises a main water inlet pipe and a main water outlet pipe, wherein the main water inlet pipe is fixedly connected with a suspension bracket, and the main water outlet pipe is fixedly connected with the suspension bracket.

Optionally, the first valve module layer, the second valve module layer and the third valve module layer are respectively and correspondingly provided with two four-way valves, two long water pipes and an interlayer water pipe, one interlayer water pipe is connected between the four-way valves of the adjacent valve module layers, a first horizontal valve port of one four-way valve of the same valve module layer is connected with the long water pipe, a second horizontal valve port is connected with the short water pipe, a first horizontal valve port of the other four-way valve is connected with the long water pipe, a second horizontal valve port is connected with the short water pipe, an upper valve port of one four-way valve of the first valve module layer is connected with a main water inlet pipe, and an upper valve port of the other four-way valve is connected with a main water outlet.

Optionally, the optical fiber cable comprises two optical fiber channels, wherein one optical fiber channel is fixedly connected with one suspension bracket, and the optical fiber channels are arranged diagonally.

A flexible direct current transmission system comprises the suspension type converter valve tower device.

The technical scheme of the invention has the following advantages:

1. The present invention provides a suspension type converter valve tower device, comprising: a valve module layer; the valve module comprises a valve module layer, a first suspension type insulating rod, a valve module layer and a valve cover, wherein one end of the first suspension type insulating rod is fixedly connected with the valve module layer, the other end of the first suspension type insulating rod is suitable for being fixedly connected with a valve hall roof steel beam, so that the valve module layer is in a suspension state, the valve module layer is suitable for keeping the minimum insulation distance with the ground, and vehicles and personnel can pass through the ground. Through the setting of first suspension insulator spindle, make valve module layer be in suspension state, keep minimum insulating distance between valve module layer and ground, be convenient for ground through vehicle and personnel, maintenance vehicle and personnel need not to avoid valve module layer any more to maintenance efficiency has been promoted.

2. The invention provides a suspension type converter valve tower device, wherein a valve module layer comprises two valve module components, the two valve module components are fixedly connected to form the valve module layer, and each valve module layer is provided with two valve module components.

3. The valve module layer is divided into a first valve module layer, a second valve module layer and a third valve module layer, the first valve module layer is fixedly connected with a first suspension type insulating rod, the first valve module layer is fixedly connected with the second valve module layer through the second suspension type insulating rod, the second valve module layer is fixedly connected with the third valve module layer through the second suspension type insulating rod, and the function of connecting the valve module layers is achieved through the second suspension type insulating rod.

4. The invention provides a suspension type converter valve tower device, each valve module assembly comprises a first girder, a second girder, a third girder, a suspension type pull rod and a plurality of submodules, wherein the first girder and the second girder are arranged in parallel, the first girder and the second girder are arranged at intervals, each submodule is fixedly connected with the first girder and the second girder respectively through the suspension type pull rod, the number of the third girders is two, one third girder is arranged at one end of the first girder and one end of the second girder, the other third girder is arranged at the other end of the first girder and the other end of the second girder, and the third girders are fixedly connected with the first girder and the second girder respectively to form a frame. The frame encloses the sub-modules to provide a load bearing for the sub-modules through the frame.

5. According to the suspension type converter valve tower device provided by the invention, the second suspension type insulating rod is arranged between the third main beams among the valve module assemblies of the adjacent valve module layers, so that the second suspension type insulating rod is connected with the valve module layers at the upper layer and the lower layer.

6. The invention provides a suspension type converter valve tower device which further comprises two suspension brackets, wherein the two suspension brackets are symmetrically arranged, each suspension bracket is fixedly connected with a first valve module layer and a valve hall roof steel beam respectively, and the suspension brackets are used for suspending other components.

7. The invention provides a suspension type converter valve tower device, which also comprises a cooling component, wherein the cooling component comprises a main water inlet pipe and a main water outlet pipe, the main water inlet pipe is fixedly connected with a suspension bracket, and the main water outlet pipe is fixedly connected with the suspension bracket to play a role in suspending the main water inlet pipe and the main water outlet pipe.

8. The invention provides a suspension type converter valve tower device, wherein a first valve module layer, a second valve module layer and a third valve module layer are respectively and correspondingly provided with two four-way valves, two long water pipes, two short water pipes and an interlayer water pipe, one interlayer water pipe is connected between four-way valves of adjacent valve module layers, a long water pipe is connected with a first horizontal valve port of one four-way valve of the same valve module layer, a short water pipe is connected with a second horizontal valve port, a long water pipe is connected with a first horizontal valve port of the other four-way valve, a short water pipe is connected with a second horizontal valve port of the other four-way valve, an upper valve port of one four-way valve of the first valve module layer is connected with a main water inlet pipe, and an upper valve port of the other four-way valve is connected with a main water outlet to form a cooling assembly.

9. The invention provides a suspension type converter valve tower device, which also comprises two optical fiber channels, wherein one optical fiber channel is fixedly connected with one suspension bracket, and the optical fiber channels are arranged diagonally so as to transmit signals.

10. The flexible direct current transmission system provided by the invention comprises the suspension type converter valve tower device, and has the advantages of any one of the above because the suspension type converter valve tower device is adopted.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of a suspended converter valve tower apparatus provided in an embodiment of the present invention;

FIG. 2 is a front view of a suspended converter valve tower apparatus provided in an embodiment of the present invention;

FIG. 3 is a left side view of a suspended converter valve tower apparatus provided in an embodiment of the present invention;

FIG. 4 is a schematic illustration of a valve module assembly provided in an embodiment of the present invention;

FIG. 5 is a schematic diagram of a sub-module and a suspension tie provided in an embodiment of the present invention;

FIG. 6 is a three view of a valve module assembly provided in an embodiment of the present invention;

FIG. 7 is a schematic illustration of a suspension link provided in an embodiment of the present invention;

FIG. 8 is a schematic view of a cooling assembly provided in an embodiment of the present invention;

FIG. 9 is a schematic diagram of a cooling assembly and a fiber channel provided in an embodiment of the present invention.

Reference numerals illustrate: 101. a first suspended insulating rod; 102. a second suspended insulating rod; 103. a hanging bracket; 201. a main water inlet pipe; 202. a four-way valve; 203. an interlayer water pipe; 204. a long water pipe; 205. a short water pipe; 206. a main water outlet pipe; 301. a fiber channel; 400. a valve module assembly; 401. a sub-module; 402. a suspension type pull rod; 403. a first main beam; 404. a second main beam; 405. a third main beam; 406. a fourth main beam; 407. a support rod; 408. connecting a busbar; 500. a pressure equalizing shielding cover; 600. a busbar path; 701. and a damping member.

Detailed Description

The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.

One embodiment of a suspended converter valve tower apparatus as shown in fig. 1-9, comprises: a three-layer valve module layer, and a plurality of first suspension insulating rods 101 suspending the valve module layer.

As shown in fig. 1, the number of the first suspension type insulating rods 101 is eight, one end of each first suspension type insulating rod 101 is suitable for being fixedly connected with a valve hall roof steel beam, the other end of each first suspension type insulating rod is fixedly connected with a valve module layer, the minimum insulation distance between the valve module layer and the ground is kept, and vehicles and personnel can be safely maintained on the ground. In order to adjust the length error of the first suspension type insulation rods 101 caused by manufacturing and installation, a damping piece 701 is correspondingly arranged between each first suspension type insulation rod 101 and the valve hall roof steel beam, and the damping piece 701 can also provide buffering for the first suspension type insulation rods 101.

As shown in fig. 1,2 and 3, the valve module layer is sequentially divided into a first valve module layer, a second valve module layer and a third valve module layer from top to bottom, wherein the upper part of the first valve module layer is fixedly connected with the first suspension insulating rod 101. As shown in fig. 1,2 and 3, the first valve module layer is fixedly connected with the second valve module layer through a second suspension type insulating rod 102, and the second valve module layer is fixedly connected with the third valve module layer through a second suspension type insulating rod 102.

As shown in fig. 1, 2, 3 and 4, the first, second and third valve module layers include two valve module assemblies 400, respectively. As shown in fig. 4, each valve module assembly 400 includes a first main beam 403, a second main beam 404, a third main beam 405, a suspension rod 402 and seven sub-modules 401 arranged at intervals, where the number of the first main beam 403 and the second main beam 404 is one, the number of the third main beam 405 is two, the first main beam 403 and the second main beam 404 are parallel and arranged at intervals, and the lengths of the first main beam 403 and the second main beam 404 are equal, the third main beam 405 is located below the first main beam 403 and the second main beam 404, i.e., one third main beam 405 is located at one end of the first main beam 403 and one end of the second main beam 404, the other third main beam 405 is located at the other end of the first main beam 403 and the second main beam 404, the third main beam 405 is fixedly connected with the first main beam 403 and the second main beam 404 respectively to form a frame, and the length direction of the third main beam 405 is perpendicular to the length direction of the first main beam 403 and the second main beam 404 respectively. Specifically, the first main beam 403, the second main beam 404, and the third main beam 405 are i-beams. To enhance the strength of the third beam, a support bar 407 is provided between two third main beams 405 of the same valve module assembly 400, as shown in fig. 4. As shown in fig. 4, the sub-module 401 is located in the frame and below the first main beam 403 and the second main beam 404, and in order to fixedly connect the sub-module 401 with the first main beam 403 and the second main beam 404, a suspension type pull rod 402 is further provided, and the sub-module 401 is fixedly connected with the first main beam 403 and the second main beam 404 through the suspension type pull rod 402. As shown in fig. 7, two ends of the suspension type pull rod 402 are respectively provided with a pin shaft hole, and are connected with the submodule 401 and the main beam through pin shafts, and the axes of the two pin shaft holes are mutually perpendicular. In order to avoid the shake of the sub-modules 401, a fourth main beam 406 is further disposed below the sub-modules 401, that is, the length direction of the fourth main beam 406 is parallel to the length direction of the first main beam 403, so as to be fixedly connected with each sub-module 401 through the fourth main beam 406, ensure that the sub-modules 401 are integrally linked when shake, and avoid collision between each other. As shown in fig. 5, each sub-module 401 is fixed by three suspension links 402, that is, one suspension link 402 of each sub-module 401 is fixedly connected to the second main beam 404, and the other two suspension links 402 are fixedly connected to the first main beam 403. As shown in fig. 6, adjacent sub-modules 401 of the same valve module assembly 400 are connected by a connection busbar 408, two valve module assemblies 400 of the same valve module layer are connected by a same-layer busbar, and adjacent valve module layers are connected by a cross-layer busbar to form a busbar path 600.

As shown in fig. 1, 2 and 3, the same valve module layer is fixedly connected by two valve module assemblies 400, two first girders 403 of the two valve module layers are arranged in parallel, and the two first girders 403 are equal in height and level, and it should be noted that the first girders 403 and the second girders 404 in the same valve module layer are arranged in a manner of 'first girders 403-second girders 404-first girders 403', that is, after one valve module assembly 400 is placed, the other valve module assembly 400 is placed after being rotated 180 degrees, so that the valve module layer is formed by the two valve module assemblies 400 with the same structure and electrical function. As shown in fig. 1, 2 and 3, the valve module assembly 400 of the first valve module layer is fixedly connected with the valve module assembly 400 of the second valve module layer through the second suspension insulating rod 102, the valve module assembly 400 of the second valve module layer is fixedly connected with the valve module assembly 400 of the third valve module layer through the second suspension insulating rod 102, and it should be noted that the valve module assemblies 400 belong to an up-down relationship, and in the valve module assembly 400 of the second valve module layer, the central axes of the second suspension insulating rods 102 above and below the third main beam 405 are overlapped. As shown in fig. 4, the valve module assembly 400 belonging to the first valve module layer and the second valve module layer is provided with two second suspended insulating rods 102 disposed at intervals under each third main beam 405 of the valve module assembly 400, that is, one valve module assembly 400 of the first valve module layer and the second valve module layer is provided with four second suspended insulating rods 102. As shown in fig. 1, a first suspended insulating rod 101 is disposed above a third main beam 405 of the valve module assembly 400 belonging to the first valve module layer, and central axes of the first suspended insulating rod 101 and the second suspended insulating rod 102 coincide.

As shown in fig. 1, 2 and 3, the valve house further comprises two suspension brackets 103, the two suspension brackets 103 are symmetrically arranged, and each suspension bracket 103 is fixedly connected with the first valve module layer and the valve house roof steel beam respectively. As shown in fig. 1 and 3, the suspension bracket 103 is disposed between two valve module assemblies 400 of the first valve module layer, and the suspension bracket 103 has a ladder shape, and two second main beams 404 of the same suspension bracket 103 are fixedly connected.

For cooling the sub-module 401, the cooling assembly is further included, as shown in fig. 1, the cooling assembly includes a main water inlet pipe 201 and a main water outlet pipe 206, and the main water inlet pipe 201 and the main water outlet pipe 206 are fixedly connected with a suspension bracket 103 respectively, and the main water inlet pipe 201 and the main water outlet pipe 206 are arranged diagonally. As shown in fig. 4, 8 and 9, the first valve module layer, the second valve module layer and the third valve module layer are respectively provided with two four-way valves 202, two long water pipes 204, two short water pipes 205 and an interlayer water pipe 203 correspondingly, one interlayer water pipe 203 is connected between the four-way valves 202 of the adjacent valve module layers, a first horizontal valve port of one four-way valve 202 of the same valve module layer is connected with the long water pipe 204, a second horizontal valve port is connected with the short water pipe 205, a first horizontal valve port of the other four-way valve 202 is connected with the long water pipe 204, a second horizontal valve port is connected with the short water pipe 205, an upper valve port of one four-way valve 202 of the first valve module layer is connected with the main water inlet pipe 201, and an upper valve port of the other four-way valve 202 is connected with the main water outlet pipe 206. As shown in fig. 8 and 9, the long water pipe 204 and the short water pipe 205 are L-shaped, one end of the long water pipe 204 and one end of the short water pipe 205 are connected with the four-way valve 202, and the other end is connected with the sub-module 401, so as to form a circulating water path between the same-valve module layers, and compared with the traditional design, the circulating water path has the effects of saving space and cost.

As shown in fig. 1, 8 and 9, two fiber channels 301 are further included, one fiber channel 301 is fixedly connected to one suspension bracket 103, and the two fiber channels 301 are disposed diagonally. Each fiber channel 301 is disposed corresponding to the fiber notch of one valve module assembly, as shown in fig. 1, since one valve module assembly 400 of the same valve module layer is disposed after being rotated 180 degrees and the other valve module assembly 400 is disposed after being rotated 180 degrees, the fiber notch of the valve module layer is exactly in a diagonal state. Meanwhile, the two optical fiber channels 301 arranged diagonally are convenient for a person to count the optical fiber numbers of the optical fiber channels 301 from the left hand side when facing any valve module assembly during maintenance.

As shown in fig. 1,2 and 3, a tubular annular equalizing ring is disposed at the periphery of each valve module layer, and tubular U-shaped equalizing rings are disposed at the bottoms of the uppermost first valve module layer and the lowermost third valve module layer to enclose the equalizing shield 500 forming the suspended converter valve tower device. It should be noted that, the uniformity ring of each valve module layer is fixed on the first main beam 403 or the second main beam 404, and because the first main beam 403 and the second main beam 404 are made of metal materials, an equipotential body is formed after the first main beam 403 and the second main beam 404 are connected with each other, and the equipotential body is formed by the equipotential ring and the main beam when the equipotential ring is fixed on any main beam, therefore, the equipotential ring connected with each valve module assembly has the same electric potential, the electric potential is clear, and the external field intensity of the equipotential ring is more uniform.

A flexible direct current transmission system comprises a plurality of suspension type converter valve tower devices.

As an alternative embodiment, the number of valve module layers may also be 1, 2, 4 or even more layers.

As an alternative embodiment, the valve module assemblies 400 within the same valve module layer may also be 1, 3, 4 or even more.

As an alternative embodiment, the number of sub-modules 401 within the valve module assembly 400 may also be 1,2,3 or even more.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.

Claims (10)

1. A suspended converter valve tower apparatus, comprising:

A valve module layer;

The valve module comprises a first suspension type insulating rod (101), one end of the first suspension type insulating rod (101) is fixedly connected with a valve module layer, the other end of the first suspension type insulating rod (101) is suitable for being fixedly connected with a valve hall roof steel beam, so that the valve module layer is in a suspension state, the valve module layer is suitable for keeping the minimum insulation distance with the ground, and vehicles and personnel are maintained on the ground.

2. A suspended converter valve tower device according to claim 1, characterized in that the valve module layer comprises two valve module assemblies (400), the two valve module assemblies (400) being fixedly connected to form a valve module layer.

3. The suspended converter valve tower device according to claim 2, wherein the valve module layer is divided into a first valve module layer, a second valve module layer and a third valve module layer, the first valve module layer is fixedly connected with a first suspended insulating rod (101), the first valve module layer is fixedly connected with the second valve module layer through a second suspended insulating rod (102), and the second valve module layer is fixedly connected with the third valve module layer through a second suspended insulating rod (102).

4. A suspended converter valve tower device according to claim 3, wherein each valve module assembly (400) comprises a first main beam (403), a second main beam (404), a third main beam (405), a suspension pull rod (402) and a plurality of sub-modules (401), the first main beam (403) and the second main beam (404) are arranged in parallel, the first main beam (403) and the second main beam (404) are arranged at intervals, each sub-module (401) is fixedly connected with the first main beam (403) and the second main beam (404) respectively through the suspension pull rod (402), the number of the third main beams (405) is two, one third main beam (405) is arranged at one end of the first main beam (403) and one end of the second main beam (404), the other third main beam (405) is arranged at the other end of the first main beam (403) and the other end of the second main beam (404), and the third main beam (405) is fixedly connected with the first main beam (403) and the second main beam (404) respectively to form a frame.

5. A suspended converter valve tower device according to claim 4, characterized in that a second suspended insulation rod (102) is provided between third main beams (405) between valve module assemblies (400) of adjacent valve module layers.

6. The suspended converter valve tower device according to claim 5, further comprising two suspension brackets (103), wherein the two suspension brackets (103) are symmetrically arranged, and wherein each suspension bracket (103) is fixedly connected with the first valve module layer and the valve hall roof steel beam, respectively.

7. The suspended converter valve tower device according to claim 6, further comprising a cooling assembly comprising a main water inlet pipe (201) and a main water outlet pipe (206), said main water inlet pipe (201) being fixedly connected to a suspension bracket (103), said main water outlet pipe (206) being fixedly connected to a suspension bracket (103).

8. The suspended converter valve tower device according to claim 7, wherein the first valve module layer, the second valve module layer and the third valve module layer are respectively provided with two four-way valves (202), two long water pipes (204) and an interlayer water pipe (203) correspondingly, one interlayer water pipe (203) is connected between the four-way valves (202) of the adjacent valve module layers, a long water pipe (204) is connected to a first horizontal valve port of one four-way valve (202) of the same valve module layer, a short water pipe (205) is connected to a second horizontal valve port of the other four-way valve (202), the long water pipe (204) is connected to a first horizontal valve port of the other four-way valve (202), the short water pipe (205) is connected to a second horizontal valve port of the other four-way valve (202), and the upper valve port of the first four-way valve (202) is connected to the main water inlet pipe (201).

9. A suspended converter valve tower device according to claim 6, further comprising two fibre channels (301), one fibre channel (301) being fixedly connected to one suspension bracket (103), said fibre channels (301) being arranged diagonally.

10. A flexible direct current transmission system comprising a suspended converter valve tower apparatus according to any one of claims 1-9.