RU2150763C1 - Disconnecting switch - Google Patents

Abstract

FIELD: electrical engineering; circuit- opening devices. SUBSTANCE: disconnecting switch has frame-mounted ribbed insulating members coated with sealing compound and protective layer, as well as knife-blades with hooks and/or rings, and contacts for connecting power supply and outgoing buses arranged within frame plane. Novelty is that insulating members are one-piece structures in the form of cylinders with taper ribs, gaps, and double-ended flat parallel bevels in the form of segments according to phase number, with holes made in them to connect conducting members of contact blades. Each insulating member is rigidly fixed on two sides of frame by means of flat oval terminators with bevel slots. Contacts holding the blades are provided with turning pins. EFFECT: simplified design, facilitated manufacture and wiring, improved reliability and economic efficiency. 7 dwg

Description

 The invention relates to electrical engineering, namely to disconnectors designed to disconnect electrical installations or high-voltage lines of a distribution network.

A disconnector is known in which fixed contacts are fixed on three insulators, chopping knives are set on three others, which are set in motion when switching on and off by insulating rods and a lever system. [1]
The disadvantage of this disconnector is an unstable arrangement of current-carrying elements (insulators are fastened only at one point of the bracket), a large number of insulating elements and a complex kinematic scheme for moving knives when turned on and off, which reduces reliability and complicates the manufacture and installation, requires large resources for manufacturing, which leads to high energy intensity of products. In operation, knife backlash occurs, which makes it difficult to turn on, and damage is possible.

 Also known is a disconnector with spacers and soft gaskets under the insulators. They protect insulators from damage when exposed to dynamic forces arising from short-circuit currents.

Disconnectors of this type are equipped with a complex kinematic scheme, the location of live elements is unstable, and the design of the disconnector is complicated by additional elements (spacers, gaskets). [2]
Also known is the switchgear currently widespread in the distribution networks, comprising insulating elements mounted on the frame with horizontal knives mounted on them, supply buses with contacts, discharge tires with flexible inserts and a manual mechanical drive. [3]
This disconnector also has the following disadvantages: the on-off kinematic scheme is complex. To set the knives in motion, it is necessary to have pivoting levers at each movable insulator, interconnected by a common rod, on which a vertical metal rod is mounted with a drive at the bottom of the rack. During ceilings, an electric arc often destroys insulators, which leads to prolonged outages and accidents. The voltage across the insulation structure is unevenly distributed. A high electric field is created at insulators near live parts. It causes accelerated aging, especially due to ionized breakdown, which is very unfavorable for new polymer insulators. In the short-circuit current mode, the insulators are subjected to a bending load, which is unfavorable for many insulating materials from which the insulators are made (porcelain, glass), due to which the dimensions of the insulators increase significantly.

 Therefore, the disconnector has a relatively large weight, inconvenient during transportation and movement, difficult to install and unreliable in operation. In addition, rotary insulators, especially with knives, have two unreliable connections made using cement (pins with insulators and the base of knives with insulators), which, when the disconnector is operated frequently with impact and torsion loads during on-off processes, structural damage. These damages are amplified by moisture penetrating into the microcracks during freezing and thawing.

 In addition, all of the above analogues have one common drawback, they are very dangerous for birds that sit on the disconnector. This is facilitated by the horizontal arrangement of the design of the disconnector mounted on the support with the help of a volumetric support frame, which is far visible to flying birds due to its significant size and location on the upper part of the free-standing support.

 Insulators made of traditional materials specified in analogues, such as glass or porcelain, which are fragile in nature, often undergo splitting - splitting during mechanical stress: during transportation and during loading and unloading, as well as during thermal stress during emergency ceilings, shooting at them also causes similar damage.

 Insulators made of polymeric materials do not have these disadvantages.

 The closest in technical essence to the invention is a disconnector [4] containing insulating elements mounted in the plane of the frame, made in the form of two rods assembled on a sealant layer deposited on the surface of the rib rods, creating an increased creepage distance. Contact busbars and discharge busbars are also mounted on the rods.

 The disadvantages of this disconnector are the multi-operation of its manufacture, which consists in a single nozzle of the ribs on the rod with a pre-applied sealant; the complexity of the nozzle and the strengthening of metal terminators; the probability of gaps between the rod and the surface of the ribs, which can be filled with contaminated moisture, which can create destruction processes under the influence of an electric field, which in some cases cause tracking ionization of the gap and breakdown along the rod. It presents difficulties and equipment disconnector in the manufacture.

 For fixing knives and contacts, platforms with holes are required, and it is necessary to cut off part of the round surface of the rod and part of the protective coating with a mill before drilling holes, which requires subsequent fixing work.

 The aim of the present invention is to simplify the design, manufacturing technology, installation, giving versatility to insulating elements for their use against the overlapping of wires on overhead lines, to prevent damage to birds, that is, increase reliability, efficiency.

 This goal is achieved by the fact that in the disconnector containing insulating elements mounted on the frame, covered with a layer of sealant and a protective layer, with ridges-ribs on them, knives with hooks and / or rings and contacts to which are connected the supply and outgoing buses located in the plane of the frame, it is new that the insulating elements are made integral in the form of a cylinder with conical protrusions, gaps and flat double-sided parallel sections in the form of segments in the number of phases with molded holes for crepe eniya conductive contact elements, knives. In addition, each insulating element is rigidly fixed to the frame on both sides by means of flat oval shaped terminators with beveled grooves, and the contacts in which the knives are fixed are equipped with rotary axes.

 The disconnector device is shown in FIG. 1, 2, 3, 4, 5, 6, 7.

 FIG. 1. General view of the disconnector with the frame in the plan.

 FIG. 2. Disconnector - side view, without grounding knives and with drive only from the rod.

 FIG. 3. Disconnector - side view with grounding knives.

 FIG. 4. Disconnector - end view (kinematics).

 FIG. 5. An insulating element with pads for mounting conductive fittings and terminators for mounting on the frame.

 FIG. 6. The site of attachment of the knife to the insulating element and the outgoing wire. The knife is fixed on the axis.

 FIG. 7. Disconnector with two-way disconnection.

 The disconnector includes a frame 1 with insulating elements 2. The insulating elements are mounted on a frame with a frame 3. They have cavities 4 and protrusions 5. To save material and torsion resistance, the insulating elements can be made in the form of basalt-plastic or fiberglass hollow pipes filled with polyurethane. The insulating elements can be made discrete with a building length equal to the interfacial distance, and equipped with connecting fasteners.

 Conducting parts are mounted on the insulating elements: contacts 6 with the supply busbars 7 and contacts 8 with the outgoing busbars 9. Moreover, in contact 8 there is an opening with an axis 10 for attaching the knife 11 and its turns during operation "B-O". Knives can be made in pairs of different lengths.

 The outgoing tire is mounted on the protrusion of the contact 8. The contact with the knife is fixed on the site 12 with the help of the studs 13, which pass into the formed holes 14 in advance on the platforms.

 For the operation “B-O” of the knives, they have hook holes (bracket, ring) 15. The fastening of the insulating elements to the frame is carried out with the help of terminators 16, which inside have a groove 17 in which the bolt or wire 18 is located when the insulating element used on a disconnector or as an interphase spacer. To pass the wire into the groove, the terminal has an oblique passage. The bevel prevents the wire from slipping out of the spacer (insulating element).

 The disconnector is equipped with grounding knives 19 mounted on the lower axis 20, mounted on the frame corners located transversely, 21. The axis at the end has a lever with an eye 22, into which the tip of the insulating rod is inserted, which enables the grounding knives to turn on and off 23 main knives through the rod insulators and blocking. The disconnector is mounted on the support using clamps, for which there are holes 24 and hinges 25 on the lower part of the frame.

 In FIG. 5 shows an insulating element with three pads and terminators.

DISCONNECTOR WORK
The initial position is disabled. In this case, the knives 11 are pulled out of the upper contacts and set aside, and the grounding knives 19 are included.

 When the position is on, the knives enter the upper contacts 6, the grounding knives 19 are disabled. Operations with a disconnector installed vertically at (B-O) are performed as follows.

 In FIG. 1, 2, the disconnector can be turned on using hooks 15 located on the upper ends of the knives 11. The rod is brought into engagement with it and the knife is brought into contact or pulled out.

 The disconnector is turned off in the reverse order, i.e. the rod is inserted into the eye 22 (ring) of the knife and rotates downward, thereby the knife 11 leaves contact 6 and turns off. This is repeated in all three phases. With the simultaneous inclusion of the knives, they are fixed to each other rigidly on the same axis.

 The disconnector can turn on and off both 3-phase and single-phase circuit, fixing the position of the knives. It is allowed to disconnect the 6-10 kV overhead line when the transformer is idling with an open-circuit current of up to 10 A. 75% of disconnections in single-phase distributors that are disconnected automatically by the proposed disconnector.

 For fastening the insulating elements to the frame with a bolt or wire, if used, an insulating spacer (on 0.4-6-10 kV OHL), it is equipped with a terminal 16 having an oval hole with a cut and a channel with inclined walls.

 For the manufacture of insulating elements, advanced materials are used, for example, PET-G type [5], tested for tracking resistance according to IEC-12. The insulating elements used as spacers are installed energized using an insulating rod in the center of the span.

 To save materials (metal), labor costs and, therefore, cheaper, operational switching is carried out by an insulating rod, which eliminates the need for a mechanical drive, usually installed along the support.

 When installed vertically, the disconnector is safe for birds, as prevents their landing on live parts.

 The mass of this disconnector is significantly (7-8 times) less than the mass of traditional disconnectors, if a comparative characteristic is taken into account the frames on which the disconnectors are mounted. This facilitates installation and operation, reduces transportation costs, which gives significant resource savings.

SOURCES OF INFORMATION
1. Catalog 02.06.46-77. type of IV (3) RON.

 2. A.S. USSR N 137150, class 21c, 28/08, publ. 1961

 3. A.S. USSR N 358736, H 01 H, 31/10, publ. 1972

 4. A.S. USSR N 864368, publ. 1981, H 01 H 31/00 (prototype).

 5. A.S. USSR N 1669944, publ. 1991, class C 08 L 63/00.

Claims (1)

 A disconnector containing insulating elements mounted on the frame with protrusions-ribs on them, knives with contacts to which supply and outgoing busbars are located, located in the plane of the frame, characterized in that the insulating elements are coated with a sealant and a protective layer, the knives are made with hooks and / or rings, insulating elements are made integral in the form of a cylinder with conical protrusions-ribs, spaces and flat double-sided parallel sections in the form of segments in the number of phases with holes formed in them for mounting the conductive element contacts, blades, wherein each sealing element is rigidly fixed to the frame on both sides by flat oval end fittings with oblique slots, the contacts, in which the fixed blades are provided with pivot axes.

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