Method for installing nonlinear surge arrester in complete gas-insulated switchgear

Abstract

FIELD: electrical engineering.SUBSTANCE: invention relates to high-voltage equipment, in particular to high-voltage gas-insulated switchgear units (GIS). The method for installing a non-linear surge arrester (NLSA) in a complete gas-insulated switchgear comprising gas-filled high-voltage bushings consists in the fact that a supporting metal structure with mounting places for installing the NLSA is placed in the central part of the complete switchgear between gas-filled high-voltage bushings of the same phase in such a way that the overall dimensions of the supporting metal structure do not extend beyond the overall dimensions of the complete switchgear, the NLSA is installed on the mounting places of the supporting metal structure, arranging them at an angle of 90° to the axis of the switch pole and at an angle from 0 to 90° to each other, ensuring the required insulation distances to the grounded and live elements of the complete switchgear, the surge arrester is connected to the inputs of the complete switchgear by a conductive connection adapted for changing the connection point from the line input to the transformer input and back without dismantling the surge arrester from the supporting metal structure. The method for installing surge arresters in switchgear is applicable both for transporting and installing switchgear as part of a mobile substation in hard-to-reach places, in particular in conditions of extremely low temperatures, by any type of transport, and for using the proposed switchgear configuration as part of stationary substations.EFFECT: ensuring the required insulating distances between high-voltage devices, as well as in ensuring the possibility of changing the point of electrical connection of the surge voltage limiter (SVL) in the gas-insulated switchgear (GIS) without moving the SVL on the transport platform.3 cl, 4 dwg

Description

[0001] The invention relates to the field of electrical engineering, to high-voltage equipment, in particular to high-voltage gas-insulated switchgear units (GIS).

[0002] High-voltage switchgear (GIS) consists of individual modules (high-voltage units) that are functionally connected to each other in a specific sequence via current-carrying elements, thus implementing various electrical circuits of the substation's main circuit. High-voltage GIS units may include circuit breakers, disconnectors, earthing switches, current and voltage transformers, overhead and cable bushings, and surge arresters. The composition of the switchgear assembly may vary depending on the GIS's intended purpose and customer requirements.

[0003] GIS switchgear is used in electrical substations for switching electrical circuits under normal and emergency conditions, as well as for operation during automatic reclosing cycles, as well as for disconnecting and connecting de-energized circuits and, if necessary, grounding them in three-phase AC networks. Furthermore, switchgear is designed to transmit measurement signals to measuring instruments, protection, signaling, and control devices. GIS configured in this manner can be used for both fixed and mobile installations and is widely used in applications requiring compact switchgear placement. The compact mobile GIS configuration is required for transportation and installation in hard-to-reach locations, including in extremely low temperatures, using any mode of transport.

[0004] A known solution for a method of installing a non-linear surge arrester (OSA) in a switchgear (gas regulating unit) of a mobile substation (patent CN 202513479, publication date 10 / 31 / 2012, SPK H02B 7 / 00, H02B 1 / 00, H02B 1 / 20, B60P 3 / 00). The utility model relates to a mobile substation, which comprises a high-voltage power distribution device, a main transformer, an intelligent control device for the main transformer, a low-voltage power distribution device, an intelligent protective communication device, and a station power supply device. According to the description of the mobile substation, it is characterized in that the surge arrester (OSA) connected to the switchgear is installed above the intelligent control device for the main transformer (control cabinet). The installation of the OSA connected to the switchgear is carried out using supporting metal structures on the high-voltage line side.

[0005] The disadvantage of the installation is the need to increase the length of the transport platform for installing the surge arrester in order to meet the requirement for insulating distances between high-voltage nodes, as well as the inability to change the point of electrical connection of the surge arrester to the switchgear without rearranging the surge arrester itself on the transport platform; the connection is made either from the power transformer side to the transformer input of the switchgear, or from the line side to the line input of the switchgear and cannot be changed during operation.

[0006] A solution is known for a method for installing a nonlinear surge arrester (SNLA) in a mobile switchgear (GIS) at a mobile (portable) substation (patent CN 203166366 U, publication date 08 / 28 / 2013, SPK H02B 7 / 06). The utility model relates to a mobile substation, which is characterized in that the mobile substation contains an electrical device and a transformer, as well as series-connected devices and power distribution devices. The SLA is mounted on the platform of the vehicle and connected to the GIS via a flexible conductive connection. The SLA is mounted on a supporting metal structure on the high-voltage line side (connected to the GIS line input).

[0007] The disadvantage of the installation is also the need to increase the length of the trailer vehicle (lowboy) for installing the surge arrester in order to meet the requirement for insulating distances between the units, as well as the inability to change the point of electrical connection of the surge arrester to the switchgear without rearranging the surge arrester on the transport platform; the connection is made either from the power transformer side to the transformer input of the switchgear, or from the line side to the line input of the switchgear and cannot be changed during transportation and operation.

[0008] The technical problem that the invention is aimed at solving is the need to increase the length of the transport platform for installing the arrester in a mobile substation using a switchgear in order to meet the requirement for insulating distances between high-voltage devices, as well as the impossibility of changing the point of electrical connection of the arrester in the switchgear without moving the arrester on the transport platform, which is labor-intensive and involves dismantling the switchgear, the arrester itself and its metal structures.

[0009] The technical result of the claimed invention is to ensure the required insulating distances between high-voltage devices, as well as to enable changing the electrical connection point of the surge arrester (SA) in a gas-insulated switchgear (GIS) without moving the SA on the transport platform. The shape of the metal structure and the installation location of the SA in the GIS allow for its transportation and subsequent operation without the need for dismantling to comply with special transport dimensions or other distances according to the customer's technical specifications. This SA installation method allows for connection of the SA to both the line and transformer inputs of the GIS, from both the high-voltage line side and the power transformer side, without relocating the supporting metal structures. The SA connection to the GIS inputs can be accomplished using either rigid or flexible conductive connections.

[0010] No technical solutions have been identified that match the set of essential features of the invention, which allows us to conclude that the invention complies with the patentability requirement of “novelty”.

[0011] The results of the search for known solutions in the field of high-voltage equipment with the aim of identifying features that coincide with the distinctive features of the technical solution claimed as an invention, which are different from the prototypes, showed that they do not follow clearly from the prior art, which allowed us to conclude that the claimed technical solution complies with the patentability requirement of “inventive step”.

[0012] The condition of patentability of the invention “industrial applicability” is confirmed by the example of a specific design of a cell of a complete switchgear.

[0013] The essence of the invention is explained by drawings, where:

[0014] - Fig. 1 shows a general view of the switchgear with an overvoltage limiter installed on a special supporting metal structure.

[0015] - Fig. 2 shows a general view of the switchgear as part of a mobile substation, including an overvoltage limiter connected from the side of the power transformer.

[0016] - Fig. 3 shows a general view of the switchgear as part of a mobile substation, including an overvoltage limiter connected from the high-voltage line side.

[0017] - Fig. 4 shows a general view of the mobile substation.

[0018] Fig. 1 shows a general view of the switchgear with an arrester surge arrester [1] installed on a special support metal structure [2] between the line input of the switchgear [3] and the transformer input of the switchgear [4] in such a way as to ensure the possibility of connecting the arrester surge arrester to both the line and transformer inputs of the switchgear while maintaining the required insulation distances without moving the support metal structure under the arrester surge arrester. The support metal structure [2] of the arrester surge arrester is installed between the poles of the circuit breaker unit and is secured to the base of the mobile substation in the switchgear.

[0019] Fig. 2 shows a general view of the switchgear installed on a transport platform [5] as part of a mobile substation (in a private design), including an arrester voltage limiter (OPN) connected to a power transformer [6] by means of flexible current-carrying connections [7] with the connection of the arrester voltage limiter [1] from the side of the power transformer by a flexible current-carrying connection [8] to the transformer input of the switchgear [4], while the line input of the switchgear [3] is connected to a high-voltage line by a flexible current-carrying connection [9].

[0020] Fig. 3 shows a general view of the switchgear installed on a transport platform [5] as part of a mobile substation, connected to a power transformer [6] by means of flexible current-carrying connections [7] with the connection of the surge arrester [1] from the high-voltage line side by a flexible current-carrying connection

[10] to the line input of the switchgear [3], wherein the line input [3] is connected to the high-voltage line by a flexible current-carrying connection [9].

[0021] Fig. 4 shows a general view of the switchgear with an arrester [1] installed on a special supporting metal structure [2] between the line input of the switchgear [3] and the transformer input of the switchgear [4], installed on a transport platform [5] together with a power transformer [6].

[0022] The method for installing a non-linear surge arrester in a switchgear consists of: a support metal structure is installed between the switchgear poles in such a way as to ensure the location of the arresters mounted on it at a point between the transformer and line inputs of the switchgear, while the overall dimensions of the metal structure do not extend beyond the overall dimensions of the switchgear itself. The support metal structure is shaped such that the arresters installed on special mounting locations are positioned at an angle of 90 degrees to the circuit breaker pole axis and at an angle of 0 to 90 degrees to each other, ensuring the required interphase distances between the current-carrying and grounded parts of the arresters themselves. The height and shape of the metal structure for installing the arresters ensures the required insulating distances from the current-carrying parts of the arresters to other switchgear components, both grounded and energized.One or more arresters (OSDs) can be installed on the support metal structure, depending on technical requirements. The OSDs are mounted on special mounting locations within the support metal structure and connected to it using fasteners. The OSDs can be installed on the support metal structure either during the switchgear's manufacturing process (at the factory) or at the switchgear's operating site (at the substation). The OSDs can be connected to the switchgear's bushings using either flexible or rigid external conductive connections. The OSD can be connected to both line and transformer bushings via external conductive connections without physically relocating or dismantling the bushing from the support metal structure.

[0023] The proposed method for installing surge arresters in switchgear is intended for use in stationary and mobile electrical substations, in cases where compact placement of the switchgear is required while maintaining high maintainability, as well as the ability to organize protection of substation equipment from overvoltage using surge arresters both on the power transformer side and on the high-voltage line side, with the subsequent ability to switch the point of electrical connection of the surge arrester without relocating it at the substation, either to the high-voltage line side or to the power transformer side.

[0024] The proposed method of installing surge arresters in switchgear ensures high reliability and maintainability, as well as the possibility of easy transportation and installation in hard-to-reach places, including in conditions of extremely low temperatures, by any mode of transport.

[0025] The declared method of installing the surge arrester in the switchgear is planned for implementation on the switchgear of the RUEN-UETM-110 series in a mobile version manufactured by Elmash (UETM) LLC, supplied as a high-voltage switching module for installation in mobile and stationary substations.

Claims

1. A method for installing a non-linear surge voltage limiter (SNVL) in a complete gas-insulated switchgear containing gas-filled high-voltage bushings, characterized in that a supporting metal structure with mounting locations for the surge arrester is placed in the central part of the complete switchgear between the gas-filled high-voltage bushings of the same phase in such a way that the overall dimensions of the supporting metal structure do not extend beyond the overall dimensions of the complete switchgear; The surge arresters are installed on the mounting locations of the supporting metal structure, placing them at an angle of 90° to the axis of the switch pole and at an angle of 0 to 90° to each other, ensuring the required insulating distances to the grounded and live elements of the complete switchgear; The surge arrester is connected to the inputs of the complete switchgear by a conductive connection with the possibility of changing the connection point from the line input to the transformer input and back without dismantling the surge arrester from the supporting metal structure.

2. The method according to paragraph 1, characterized in that the surge arresters are installed on the supporting metal structure in a quantity corresponding to the number of phases of the complete switchgear, and each of them is connected to the line or transformer input of the corresponding phase.

3. The method according to paragraph 1, characterized in that the OPN is installed on the supporting metal structure in a quantity corresponding to one phase of the complete switchgear, and is connected to the line or transformer input of this phase.

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