271results about How to "Reduce partial discharge" patented technology

The invention discloses a compound insulating tube busbar and a preparation method thereof in the technical field of high voltage insulated conduction. The compound insulating tube busbar comprises a conductor tube, a compound insulating layer, a semiconductor electric strip layer, a shielding layer and a sleeve, wherein, the conductor tube is positioned on the innermost layer; a plurality of the compound insulating layers and the semiconductor electric strip layers are crosswise arranged at the external part of the semiconductor tube; a copper foil layer is arranged at the external part of the semiconductor electric strip layer and the sleeve is arranged at the external part of the copper foil layer. The preparation method of the invention adopts different properties of a solid buddle-free insulating film strip and insulating liquid to enwind and solidify the shaped insulating tube busbar on the surface of the tubular conductor, which causes the production procedure to be simple and the maintenance to be simple and convenient; compared with the prior art, the compound insulating tube busbar has better insulating property and longer service life, and can be applied to bitter environments.

The invention provides a halogen-free flame retardant epoxy resin composition and a dry type transformer poured by the same. The transformer comprises a base, an iron core which is vertically arranged on the base and transformer coils, wherein an upper iron core clamps are arranged above the transformer coil; lower iron core clamps are arranged between the position below the transformer coil and the base; halogen-free flame retardant insulating cushion blocks are respectively arranged between the upper iron core clamps and the transformer coil and between the lower iron core clamps and the transformer coil; the transformer coil comprises a halogen-free flame retardant foil type winding and a halogen-free flame retardant coiling winding; each transformer coil is supported by halogen-free flame retardant foil type coil supporting board, a halogen-free flame retardant iron core clamp insulating piece is arranged between the upper iron core clamp pieces; a conductive copper bar is arranged on the lateral face; and a hanging ring and a pin are further arranged on the upper iron core clamp. According to the transformer provided by the invention, an insulating material is flame-retardant; the burning capacity of a non-metal part is very low; and no smoke exists in high-temperature combustion, and toxic substances are not decomposed, so that no environment pollution is caused, security and environmental friendliness can be achieved.

Disclosed is an epoxy resin cast dry type transformer, which comprises a low-voltage winding, two high-voltage windings, an iron core, an upper heel piece, a lower heel piece, an upper clamp, and a lower clamp. The low-voltage winding is arranged at the inner layer of the loop and the high-voltage windings are arranged at the outer layer of the loop. The low-voltage winding is made of clutch gold and is provided with an insulating interlayer which is presoaked with DMD resin. The initial loops of the high-voltage windings are located at one end of the whole loop, and the starting end of the first coil of each layer of the high-voltage windings is connected with the finishing end of the last coil of the next layer. The number of the coils of the windings descends from the inner layer to the outer layer, making the windings developing into antiparallelogram structures; a soft gridding cloth layer is arranged between each two adjacent layers; the whole medium is epoxy resin and solvent-free gridding material is arranged between the outer layers of the windings at both ends of the whole loop. The epoxy resin cast dry type transformer is reasonable in design, novel in design, large in power, and small in size, and is convenient to install and easy to maintain. The epoxy resin cast dry type transformer is safe, stable and reliable and is long in service life and low in using cost and requires no daily maintenance. The epoxy resin cast dry type transformer is of strong practicability and is applicable in power supplying departments and power consuming departments.

The invention relates to a corona-resistant groove insulation material and a preparation method thereof. The groove insulation material sequentially comprises a first adhesive layer, a first mica paper layer, a second adhesive layer, a film layer, a third adhesive layer, a second mica paper layer and a fourth adhesive layer from top to bottom, wherein the first adhesive layer, the second adhesive layer, the third adhesive layer and the fourth adhesive layer are respectively formed by nano modified adhesive, the nano modified adhesive is the adhesive which is mixed with nano powder body, the content of the nano powder body in the nano modified adhesive is 15 to 25 percent, and the granularity of the nano powder body is 20nm to 100nm. The corona-resistant service life of the insulation material can be improved by more than 50 times compared with the existing groove insulation material; and meanwhile, the paint quantity in the resin immersing process can be increased, and the mechanical property and the electric insulation performance of a curing system can be improved. In addition, the cost of the groove insulation material is lower, so that the industrialized mass production and popularization of the groove insulation material can be favored.

The invention relates to a 132kV-class 36-pulse-wave transmission rectifier transformer and belongs to the technical field of transformers. According to the technical scheme, the rated voltage of a primary side is 132kV, and the primary side is subjected to D connection and in an all-insulation structure; and a secondary side is subjected to double split and phase shifting, and the difference between phase shifting angles is 10 degrees. A single transformer outputs 12 pulse waves, and three transformers output 36 pulse waves. Low-voltage windings comprise an axially arranged low-voltage basic winding I (2) and low-voltage phase shifting winding I (3) and an axially arranged low-voltage basic winding II (7) and low-voltage phase shifting winding II (8). High-voltage windings comprise a high-voltage winding I and a high-voltage winding II which are connected in parallel vertically. By means of the rectifier transformer, the utility rate of space of the transformer is improved, and the size of the transformer and the production cost are reduced; effects of grid-side overvoltage on valve-side rectifying elements and effects of valve-side harmonic components on power grids are reduced; and the transformer is reliable in insulation, high in short-circuit bearing capacity and phase shifting angle accuracy and capable of improving power quality.

The invention discloses an axial double-split dry-type transformer coil structure with the same connection groups and a winding method. The axial double-split dry-type transformer coil structure comprises a first low-voltage coil, a second low-voltage coil and a group of high-voltage coils, wherein each of the first low-voltage coil and the second low-voltage coil is provided with two low-voltage coil sections, the two low-voltage coil sections of the first low-voltage coil and the two low-voltage coil sections of the second low-voltage coil are distributed in a cross mode, and two sections of leads for winding forming of the first low-voltage coil and the second low-voltage coil are leaded in and out from the upper end and the lower end respectively. The high-voltage coils are provided with multiple high-voltage coil sections distributed in the axial direction, the high-voltage coil sections are sequentially and mutually connected in series, and leads for winding forming of the high-voltage coils are leaded in and out from the upper end and the lower end respectively. The axial height of the first low-voltage coil and the axial height of the second low-voltage coil are both consistent to the axial height of the high-voltage coils.

An electric cable made from at least one elongated electric conductor and a multilayer insulation surrounding the electric conductor. The multilayer insulation has a first semiconducting layer and an electrically insulating layer, where the two layers are made from a silicone rubber based composition. The semiconducting silicone rubber based composition of the first semiconducting layer has carbon rovings as conductive filler.

The invention discloses a casting type split reactor. A coil of the casting type split reactor comprises a first winding and a second winding which are arranged coaxially, and encapsulation parts of the first winding and encapsulation parts of the second winding are arranged alternatively from inside to outside in sequence. A first wire inlet bar and a second wire outlet bar are arranged at an interval radially and fixed at the upper end of the coil, and the other first wire inlet bar and a first wire outlet bar are arranged at an interval radially, connected with a current introducing end of the second winding in a conductive mode and fixed at the lower end of the coil. Each encapsulation part comprises a conductive part formed by winding a plurality of multi-layer round leads, and an insulation part formed by casting epoxy resin in a vacuum mode is arranged outside the conductive part. According to the casting type split reactor, the encapsulation parts are formed by casting epoxy resin in the vacuum mode through a casting mould, consistency of sizes of the insulation layers can be ensured, and uneven thicknesses of the insulation layers are avoided. In addition, no bubbles exist in the windings, partial discharge is reduced, occurrence of air gaps can be avoided effectively, and therefore, insulation performance of the insulation layers can be improved.

The invention discloses a method for manufacturing an extra-high-voltage composite insulation paper board. The method comprises the following steps that 1) stem grafting modification is conducted on aramid fiber pulp; 2) an aramid paper board is manufactured. The high-temperature (220 DEG C) resistant performance of aramid fiber is utilized, so that the temperature which the insulation paper board is resistant to is increased to 140 DEG C-150 DEG C; the low dielectric constant of the aramid fiber ranges from 1.6 to 3.7 so that the partial discharge of extra-high-voltage transformer oil can be reduced, the electric intensity of the extra-high-voltage transformer oil and paper insulation are completely used, and the dielectric constant of the paper is reduced. The surface modification technology is conducted on the aramid fiber so that the aramid fiber can be completely merged with wood pulp fiber.

The invention relates to the technical field of electrics, in particular to a high-insulativity, high-precision and environment-friendly capacitive divider. The embodiment of the invention provides a plurality of self-healing type high-voltage capacitors with inner series structures and an outer shell, wherein the self-healing type high-voltage capacitors with the inner series structures are arranged in the outer shell, and the outer shell is filled with nitrogen gas; the series approaches among the self-healing type high-voltage capacitors with the inner series structures are arrayed in the outer shell in a cosine curve law. The embodiment of the invention can reduce the local discharge among capacitors and can reduce the size of the high-voltage capacitive divider.

The invention discloses a fruit and vegetable preservation device based on a nanosecond pulse low-voltage electric field. The fruit and vegetable preservation device comprises a treatment chamber anda nanosecond pulse electric field generating device, wherein the treatment chamber comprises a closed cavity, a box body with an open top and an upper cover arranged at the open top of the box body, the upper cover contains a copper sheet protecting path, the box body matches with the upper cover by virtue of a positioning assembly, and an electromagnetic device, the copper sheet protecting path and a work indicating lamp form a safety protection device together; and the nanosecond pulse electric field generating device comprises a nanosecond pulse power with adjustable parameters and a multichannel dual electrode sealed in an insulating barrier, and the multichannel dual electrode is connected with an electrode outgoing post. The electric field generating device forms a nanosecond pulse electric field in the box body, and fruits and vegetables are put in the nanosecond pulse electric field for performing electric field treatment, thereby achieving an enzyme inactivating effect by changing the inherent electric fields of the fruits and vegetables, inhibiting the respiratory action of the fruits and vegetables and achieving a good cold sterilization effect. The fruit and vegetable preservation device based on the nanosecond pulse low-voltage electric field has a convenient operation method, is pollution-free and suitable for preserving various perishable fruits and vegetables and has very high application value.

The invention discloses an insulation system for a stator bar in high voltage electric machines, comprising an anti-corona tape that is wound uniformly and continuously over the entire length of a bare bar. The anti-corona tape comprises a thin resistive sublayer engaged to a thick insulative sublayer. The insulative sublayer provides resistance against high voltage. The resistive sublayer protects the insulation against partial discharges. These partial discharges can occur in voids, such as delamination voids, transposition crossover gaps, strand corners, slot voids, overlap voids etc. The resistive sublayer also increases the thermal conductivity hence reduces the operating temperature. Such insulation using a single-tape approach can replace several layers used in prior-art, viz., an internal corona protection layer, an external corona protection layer, a stress-grading layer and mica layers. This single-tape approach also simplifies the process of manufacturing the stator bar and reduces its cost.

The invention discloses an integral heat shrinkable cable middle connector which comprises a conductor connecting pipe, a stress multiunit pipe, an inner insulating pipe, an outer insulating pipe, a semiconducting pipe and a sleeve multiunit pipe, wherein two ends of the conductor connecting pipe are respectively connected with the cores of two segments of cables; the stress multiunit pipe is coated outside the connection pipe, and the two ends of the stress multiunit pipe are respectively in lap joint with the insulation shielding layers of two segments of cables; the inner insulating pipe is coated outside the stress multiunit pipe; the outer insulating pipe is coated outside the stress multiunit pipe and the inner insulating pipe, and the two ends of the outer insulating pipe are respectively in lap joint with the insulation shielding layers of the two segments of cables; the semiconducting pipe is coated outside the outer insulating pipe, and the two ends of the semiconducting pipe are respectively in lap joint with copper shielding layers of the two segments of cables; and the sleeve multiunit pipe is coated outside the semiconducting pipe, and the two ends of the sleeve multiunit pipe are respectively in lap joint with the outer sleeves of the two segments of cables. Due to the adoption of the connector provided by the invention, the magnitude of partial discharge is reduced, sealing and insulating performance is strengthened. Moreover, the connector has the advantages of prolonged service life and simplicity in installation.

The invention provides a built-in transformer of a wind power tower barrel, comprising a low-voltage winding, a high-voltage winding and an iron core. The structural key points are as follows: the iron core is provided with an upper iron yoke and a lower iron yoke; a side column is respectively arranged between the left end and the right end of the upper iron yoke and the lower iron yoke; the upper and lower ends of the side column are respectively connected with the left end and the right end of the iron yoke in an overlapping manner; the middle part of the iron yoke is provided with a middle column; the upper end and the lower end of the middle column are respectively connected with the middle part of the iron yoke in an overlapping manner; the side column and the middle column are respectively provided with the winding; the inner layer of the winding is provided with low-voltage coil; the outer layer of the low-voltage coil is sheathed with a high-voltage coil; clamping units are respectively arranged at the front and rear sides of the iron yoke; the low-voltage coil is wound with a copper foil; the materials pre-impregnated by DMD resin is used as the insulation between layers; a flexible grid cloth is arranged between two adjacent layers of the high-voltage winding; and the periphery of the high-voltage is provided with the solventless grid materials. The invention is characterized by compact structure, long service life, low noise, free maintenance, high reliability, no pollution, flame retardancy and the like, the probability of partial discharge is approximately zero, and the invention can be recycled after the service life is ended up.