JPH037037A - Gas-insulated water-cooled thyristor valve - Google Patents

Abstract

PURPOSE:To reduce the number of components and to obtain a compact thyristor valve by employing a cooling water header as a means for relieving the field stress in a thyristor module and the side wall of tank. CONSTITUTION:Ring headers 28a, 28b are arranged vertically in two stages while surrounding components such as a thyristor module 1, an insulating pole 2 and a light guide 10. Cooling water is distributed uniformly to the ring headers 28a, 28b from the outside of a tank 4. The ring headers 28a, 28b are made of material having high electrical conductivity and function as shield rings for relieving the electrical field in the thyristor module 1 and the tank 4 arranged therein. By such arrangement, installation space or insulating distance need not be secured.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a thyristor valve used for direct current power transmission or interconnection between power systems with different frequencies, and particularly relates to a thyristor valve that is used for direct current power transmission or interconnection between different frequency power systems, and in particular, a thyristor valve that uses water for cooling. Regarding insulated thyristor valves.

(Prior Art) In recent years, semiconductor devices have made remarkable progress, and highly reliable high-voltage, large-current thyristor elements have been developed, and thyristor valves using these thyristor elements are increasing in capacity year by year. Therefore, with the increase in voltage and current,
The problem has been how to cool the equipment compactly and efficiently. The former can be made more compact by housing the thyristor valve in a tank filled with SF6 gas or the like having high insulation performance. In the latter case, it is preferable to use water as a cooling medium which has a high cooling effect and is available at low cost and anywhere.

A conventional example of a gas insulated water-cooled thyristor valve will be described below with reference to FIGS. 4 to 6.

4 to 6, reference numeral 1 denotes a stack 22 consisting of a plurality of thyristor elements 20 and a heat sink 21 connected in series, and its attached circuits such as a water-cooled resistor 24, a capacitor 23, a reactor 25, etc., mounted on a frame 26. This is a thyristor module placed on the top.

Note that 10 is a light guide that transmits a signal to fire the thyristor. A plurality of thyristor modules 1 are stacked vertically in multiple stages via insulating columns 2 and housed in a tank 4 filled with an insulating gas 3 such as SF6. 5
is a column that insulates and supports the entire stacked thyristor module 1. The thyristor modules 1 are electrically connected in series, and both ends thereof are connected by a main circuit conductor 6 to a bushing 7 mounted outside the tank 4. The cooling water that cools the heat-generating components inside the thyristor module 1 is connected to the outside of the tank 4 through an airtight flange 9 that connects with the outside of the tank 4, ensuring a creepage insulation distance through the cooling main piping 8 made of insulating material, and is grounded to each thyristor module 1. The water flows into each header 12 via an insulated pipe 15. header 1
The cooling water flowing into the header 2 passes through the distribution pipe 13 and the insulating pipe 14 as shown by the arrow 27 in the figure, is distributed to the heat generating parts, and returns to the header 12 again. FIG. 6 is a system diagram showing a circuit diagram of cooling water distributed to each thyristor module 1 and drained from the module.

The reason why insulated pipes are used at each location is to connect parts with different potentials. Furthermore, the upper and lower ends of the insulating thyristor module 1 in the stacking direction are provided with an upper shield 16 and a lower shield 17 for alleviating the electric field stress since the electric field stress is severe against the inner wall of the tank. In addition, the metal fittings for fixing the module frame 26 parts and the bosses of the header 12 that serve as insulating pipe connections have sharp edges against the inner wall of the tank 4, which results in severe electric field stress. A shield 18 is provided.

Although not shown, the capacitor 23 in the thyristor module 1, the pipe connection boss of the heat sink 21, and the pipe connection boss of the water-cooled resistor 24 have sharp edges with respect to the upper module frame 25. A shield cover is provided.

(Problems to be Solved by the Invention) As described above, in order to attach the cooling water pipe 13 and the side shield 18 to the thyristor module 1 at each stage, the module design becomes complicated, such as securing space and insulation distance. The outer size of the module becomes larger, and the valve as a whole also becomes larger.

The present invention solves the above-mentioned problems and provides a compact gas-insulated water-cooled thyristor valve with a small number of parts.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides that the cooling water header that distributes or discharges cooling water to each thyristor module 1 is also used for mitigating the electric field stress between the thyristor module and the tank wall surface. It is in. Therefore, each module is equipped with an electrically conductive cooling water circulation ring header (ring-shaped pipe) that surrounds all components such as the thyristor module, insulating column, cooling water insulating pipe, and light guide. , it is characterized by having both a function as a shield ring for mitigating an electric field with the inner wall of the tank and a function as a header for distributing and draining cooling water.

(Function) The headers are installed in two stages above and below each module to surround the modules and insulators that make up the thyristor valve.
It supplies cooling water to the relevant module and the upper module header, and also drains the cooling water drained from the module and the upper module header, and at the same time acts as an electric field mitigation shield with the tank inner wall. .

(Example) Hereinafter, the present invention will be explained in detail using FIGS. 1, 3, and 3.

FIG. 1 is a diagram showing a configuration example of a thyristor valve according to the invention, FIG. 2 is a diagram showing a module configuration according to the invention, and FIG. 3 is a cooling water system diagram of a ring header according to the invention.

Note that the same parts as in FIGS. 4 to 6 are designated by the same reference numerals. Cooling water is supplied from the outside of the tank 4 via the airtight flange 2 to the insulating main cooling pipe 8 to ensure a creepage insulation distance, and reaches the ring header 28 at one of the two upper and lower stages installed in each thyristor module 1. This ring header 28
A boss for the pipe 15 connecting each header 28 is provided on the inside, and the sharp edges of the component fixing fittings of the module frame 26 are not directly opposed to the inner wall of the tank 4. 1. Insulating support 2
, the light guide 10, and other parts are enclosed inside the pipe and is made of electrically conductive material such as stainless steel or copper.

Furthermore, as shown in the system diagram of FIG. 3, the upper and lower ring headers 28a and 28b of each module 1 are connected by at least one or more insulated pipes 15, so that cooling water is evenly distributed to each module. It also serves as an 81 function as a header. The ring header has two layers, upper and lower, to enhance the effect of electric field relaxation, and if necessary,
All you have to do is change the number of stages.

[Effects of the Invention] As described above, according to the present invention, the module side shield that was conventionally required can be removed, and the installation space and insulation distance are no longer required, resulting in a compact gas-insulated water-cooled thyristor. We can provide valves.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an insulated water-cooled thyristor valve showing an embodiment of the present invention, FIG. 2 is a block diagram of a thyristor module according to the present invention, and FIG. 3 is a cooling water system diagram of a ring header according to the present invention. FIG. 4 is a block diagram of a conventional gas insulated water-cooled thyristor valve, FIG. 5 is a block diagram of a conventional thyristor module, and FIG. 6 is a cooling water system diagram of a conventional module header. 1... Thyristor module, 2... Insulating support column, 3
...Insulating gas, 4...Tank, 5...Insulating column,
6... Main circuit conductor, 7... Bushing, 8... Main cooling pipe, 9... Airtight flange, 10... Light guide, 11... Airtight terminal, 12... Header 13
...Distribution pipe, 14゜15...Insulated pipe, 16...
・Top shield, 17...Lower shield, 18...
Side shield, 19... Thyristor valve, 20...
・Thyristor element, 21... heat sink, 22...
・Stack, 23... Capacitor, 24... Water-cooled resistor, 25... Reactor, 26... Frame, 2
8...Ring header

Claims (1)

[Claims] A module containing a tank filled with insulating gas, a plurality of thyristor elements, and their associated circuits are stacked in several stages using insulating supports, and connected to a specified voltage and current, and the thyristor elements are ignited. A fluid pipe is connected to the light guide that transmits the signal, the cooling body for the thyristor element in the module, and its attached circuits such as resistors and reactors, and cooling water is introduced from outside the tank and cooled by circulation. In a gas-insulated water-cooled thyristor valve, an electrically conductive thyristor module is constructed using an insulating support to surround the light guide that transmits the ignition signal of the thyristor element and the thyristor module stacked in multiple layers. A ring header (ring-shaped pipe) for circulating cooling water is provided in each stacked module, and the ring header has the function of a shield ring for mitigating the electric field with the inner wall of the tank and a header for distributing and draining the cooling water. Features a gas insulated water-cooled thyristor valve.