252 results about "Electric strength" patented technology

The invention discloses a reduction insulation structure suitable for a high-voltage motor and an insulation processing method thereof. The reduction insulation structure comprises a plurality of low resin mica tapes (2) lapped outside an electromagnetic coil (1), and is characterized in that vacuum dipping treatment is carried out by utilizing vacuum pressure dipping resin after the low resin mica tape is lapped, and the insulation structure with reduced insulation thickness is formed after baking and curing. The breakdown voltage of the insulation structure is qualified, the normal dielectric loss, the thermal state dielectric loss, the dielectric loss increment and the electrical strength of the insulation structure reach high grade.

The invention discloses a heat-conducting insulated adhesive, comprising the following components in parts by weight: 50-60 parts of epoxy resin, 5-8 parts of curing agent, 6-9 parts of plasticizer, 3-5 parts of diluent, 9-12 parts of aluminium nitride, 5-6 parts of coupling agent, and 2-3 parts of fire retardant. The heat-conducting insulated adhesive is prepared by the following steps: weighing the epoxy resin; adding the diluent; evenly stirring and heating to 160-180 DEG C; cooling at room temperature, adding aluminium nitride and the curing agent, which are processed by the coupling agent; evenly stirring and curing for 4-5 hours at 60-80 DEG C. In the manner, the heat-conducting insulated adhesive disclosed by the invention is reasonable in proportion, has excellent heat-conducting coefficient, electric strength and bonding strength, also has a plurality of functions, and can be used as heat-conducting resin, an adhesive, a coating and a potting compound.

The invention discloses a preparation method for a polyimide thin film. The preparation method comprises the steps of adding an inorganic filler dispersing liquid, the surface of which is modified by coupling agents, and dianhydride and diamine into a polarity organic solvent to be mixed, and performing condensation polymerization on the dianhydride and diamine to obtain polyamide acid resin; and performing de-foaming, curtain coating and imidization on the polyamide acid resin in sequence to obtain the polyimide thin film, wherein the coupling agents comprise a coupling agent A and a coupling agent B; the coupling agent A is selected from a silane coupling agent or a titanate coupling agent with any one reactive group of amino group, formyl group, epoxy group, isocyanato, anhydride group, sulfydryl group and the like; the coupling agent B is selected from the silane coupling agent or the titanate coupling agent comprising long-chain alkyl; and the molar ratio of the coupling agent A to the coupling agent B is 2:8-8:2. The polyimide thin film prepared by the preparation method is 165-180MPa in tensile strength, 48-60% in breaking elongation, 210-230MV/m in power frequency electric strength, and 60-80h in corona resistance service life.

The invention relates to an electric strength inspection device for oil paper compound insulation oil during flowing, belongs to the technical field of high voltage and insulation, and aims at solving the problems of difficulty in mounting and frequent flashover caused by processing errors of the existing electric strength inspection devices. The electric strength inspection device comprises a high-voltage bushing, a lower connecting piece of the high-voltage bushing, an upper electrode connecting piece, an upper electrode, an upper electrode insulating member, a lower electrode insulating member, an insulating screw rod, an insulating nut, a lower electrode, an insulating paper board, an oil duct, an earthing bolt, an oil inlet, an oil outlet, an oil inlet connecting piece and an oil outlet connecting piece, wherein the low connecting piece of the high-voltage bushing, the upper electrode connecting piece, the upper electrode, the upper electrode insulating member, the lower electrode insulating member, the insulating screw rod, the insulating nut, the lower electrode, the insulating paper board, the oil duct and the earthing bolt are arranged in a high-voltage test box, the upper electrode is arranged right above the lower electrode and is embedded in the upper electrode insulating member, the lower electrode is embedded in the lower electrode insulating member, and the upper electrode insulating member is arranged above the lower electrode insulating member.

The invention discloses an abrasive steel paperboard. The abrasive steel paperboard is prepared from the following materials in percentage by weight: 93.8%-96.8% of cotton fiber, 3%-6% of wood fiber and 0.1%-0.2% of styrene-acrylic emulsion. The manufacturing process of the abrasive steel paperboard comprises the following steps of: (1), pulping and rinsing; (2), making paper and gelling; (3), aging and desalinizing; (4), washing and gluing; (5), pre-drying and drying; and (6), carrying out press polishing and packaging. Relative to the pure-cotton fiber abrasive steel paperboard, the volume resistance of the abrasive steel paperboard disclosed by the invention is increased by 30%, the electric strength of the abrasive steel paperboard is increased by 12%, the longitudinal drying shrinkage and the transverse drying shrinkage are reduced by 6% and 15%, respectively; and compared with the water adsorption of the un-glued abrasive steel paperboard, the water adsorption of the abrasive steel paperboard provided by the invention is reduced by 14%.

The invention relates to a high-power-resistant type lead-free environment-friendly ceramic dielectric material which comprises a primary crystalline phase, an indirect material, a modified additive and a sintered fluxing agent, wherein a structural formula of the primary crystalline phase is BaTiO3; the indirect material is SrTiO3; the modified additive refers to one or more of MnCO3, TiO2, CaCO3, ZrO2, Nd2O3 and Nb2O5; the sintered fluxing agent refers to one or more of Bi2O3, ZnO, MgO and SiO2; and the ceramic dielectric material comprises the following components in parts by mole: 50-65mol% of primary crystalline phase, 30-45mol% of indirect material, 2-10mol% of modified additive and 2.5-20mol% of sintered fluxing agent. The ceramic dielectric material accords with the N4700 characteristic, has the advantages of high dielectric constant, good frequency-dielectric loss characteristics, high electric strength, uniform particle size distribution and good forming process and accords with the environment-friendly requirement.

Disclosed is a P2P (peer-to-peer) network node selecting method. The method includes: through an IP (internet protocol) address mapping library of a Tracker server, performing fast coarse granularity division on existing nodes to enable the divided nodes to have same location information, and selecting a final node list possessing requested media resources according to the location information of a request node; performing improved node selecting for delay measurement on the nodes returned by the final node list, performing electric strength test on the nodes in the node list by the request node, increasing the number of download data blocks so as to fast acquire the nodes preliminarily meeting the requirements, and selecting most suitable nodes as neighbor nodes. The method has the advantages that networking is simplified without participation of operators, establishment and maintenance cost is low, network-to-network flow is reduced, flow among operator interfaces is reduced, data congestion of a backbone network is avoided, the needed neighbor nodes can be selected fast, the selected nodes are fast in response and high in bandwidth.

The invention belongs to the technical field of high voltage and insulation, and specifically relates to a method for fluorinating an insulator through use of a CF4 plasma. According to the method, an insulator is put in a reaction cavity, a mixture of CF4 and an inert gas is fed into the reaction cavity, the insulator is processed by a discharge plasma for 2-30min at room temperature and at low pressure of 0.01-0.1atm, so CF4 and the surface of the insulator are reacted with each other to generate a fluorinated layer. The method has the characteristic that the surface of a insulator is fluorinated through plasma processing in CF4, the surface flashover characteristic of insulators is improved, the electric strength of insulators is improved, the flashover voltage can be improved by about 50% to the maximum, the hydrophobic and oleophobic properties of the surfaces of insulators are improved, and the capability of insulators to prevent wet flashover and pollution flashover is improved.

The invention discloses an epoxy resin vacuum degassing mixing tank. The mixing tank comprises a tank body (1), a tank cover (2), an electric heating device (3), a feeding hole (4), a discharge hole (5), a stirring assembly (7) and a motor and is characterized in that the bottom of the tank body (1) is turbinate; spoilers (8) are axially arranged on the cylindrical inner wall sides of the tank body (1); a vacuum valve (6) is arranged on the tank cover (2) and is connected with a vacuum pump; the stirring assembly (7) comprises a rotating shaft (9), lower stirring blades (10, 11), upper stirring blades (12, 13) and a stirring flat steel frame (14). The mixing tank substantially reduces the equipment cost, is simple to manufacture, convenient to maintain and easy to clean, can not only ensure the quality of the mixture but also improve the mixing efficiency, thoroughly eliminates the hidden danger of local friction overheat possibly occurring in the mixing process, especially can achieve good stirring effects when a few mixtures exist and greatly improves the electrical strength and mechanical strength of a transformer.

The invention relates to a small-sized hip type surface mounting (SMD) high-voltage and safety standard recognized ceramic capacitor and a manufacturing method thereof. The capacitor comprises holosymmetrical copper electrode ceramic chips, a copper belt pin and an encapsulating material, wherein the holosymmetrical copper electrode ceramic chips are cylindrical; a ceramic medium is positioned between upper and lower electrodes which are integral copper electrodes; the copper belt pin is welded and fixed with the upper and lower electrodes; the encapsulating material is used for encapsulating the copper electrode ceramic chips and one part of the copper belt pin together, and the tail end of the copper belt pin is exposed out of the encapsulating material. The manufacturing method for the capacitor comprises the following steps: inserting chips, welding, vacuum injection-molding and encapsulating epoxy resin, curing and molding at a high temperature, laser-printing product performance information and safety certification information, cutting a pin, performing full-automatic performance test, taping and packaging a reel. The capacitor has the characteristics of being stable in capacity, high in electric strength and small in size, effectively saves the surface space of a PCB (printed circuit board), and is suitable for existing small-sized and ultrathin requirements of a whole circuit of an electrical appliance product, so that the market needs are met.

The invention discloses a device and method for measuring the electrical strength of material under the stress condition. The device comprises an insulating oil tank used for encapsulating a sample to be tested, test electrodes, an electrical strength testing device and a stress generation system, wherein the test electrodes are arranged at the two sides of the sample to be tested and are connected with the electrical strength testing device by electrode leads; and the stress generation system comprises a clamping device used for clamping the sample to be tested. The method for measuring the electrical strength of the material under the stress condition comprises the following steps of: firstly encapsulating the sample in the insulating oil tank, and installing the test electrodes; then, leading the sample to be clamped on the stress generation system and connected with the electrical strength testing device, and fully filling insulating oil; starting the stress generation system for providing a load; after that, starting the electrical strength testing device, and recording the voltage values of the tested sample which is broken down along with the rise of output voltage; and finally, obtaining the electrical strength of the sample. The measurement device is simple in structure and convenient in assembly and operation, the test method is simple and convenient, the test cost is lower, and test results is accurate.

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 discloses an electrode device for measuring the electrical strength of a composite insulator silicon rubber umbrella skirt and a measuring method.The electrode device is characterized by comprising an upper plate, an upper electrode fixed with the upper plate through a bolt, a middle support plate, a lower plate and a lower electrode fixed with the lower plate through a bolt, and the vertical height of the middle support plate and the vertical height of the upper plate are adjustable.In the use process, the height of the upper surface of the middle support plate is adjusted to be flush with the upper end of the lower electrode, a silicon rubber sample wafer is put on the middle support plate, and then the position of the upper electrode is adjusted according to the thickness of the silicon rubber sample wafer to enable the electrodes to directly make tight contact with the sample wafer.In the measuring process, the measuring device is immersed in a container filled with transformer oil, a breakdown voltage value of the silicon rubber sample wafer is measured through a voltage measuring instrument, and therefore the electrical strength of the silicon rubber umbrella skirt is obtained.The electrode device is simple in structure, convenient to install, easy to maintain, convenient and rapid in use method and capable of accurately measuring the electrical strength of the composite insulator silicon rubber umbrella skirt.