37results about How to "Reduce arc voltage" patented technology

A method for testing high-voltage alternating-current power switches in a synthetic test circuit has the step of connecting a high-voltage oscillating circuit in parallel to a test switch Bt in a time interval before the current zero of an interruptible high current, which is determined by a half-cycle duration (Th / 2) of the oscillating current (ih) less the duration of equivalence (Δtse) of the sole flow of the oscillating current as sequential current in the test switch with a stress exerted upon the switch by the homogeneous current in a direct test circuit. The sequential-current flow duration of the equivalence results, at least approximately, from the comparison of the values of common physical stress parameters acting in the test switch during the test, on the one hand, in the synthetic test circuit and, on the other hand, in the direct test circuit.

A method for controlling striations in a lamp powered by an electronic ballast includes the steps of generating an asymmetric lamp current using an unbalanced circuit component in the electronic ballast and supplying that current to the lamp. The unbalanced circuit component may be an unbalanced output transformer or an unbalanced DC choke. The output transformer is unbalanced by offsetting the number of turns on each side of the tap on the primary winding of the transformer. In a similar manner, the DC choke is unbalanced by offsetting the number of turns in each winding of the choke.

The invention discloses a mold for forming a quartz crucible, which comprises a metal alloy mold, an outer mold, a porous alloy base, a rotating table, and a rotating shaft. The outer layer of the metal alloy steel mold is covered with an outer mold. The metal alloy steel mold The bottom of the mold is equipped with a porous alloy base, and the porous alloy base is placed on a rotating table, and a rotating shaft is arranged under the rotating table. The present invention has the advantages of high strength, long service life, efficient use of heat energy, and reduced power consumption. Advantages, the invention increases the melting temperature, can quickly remove metal impurities in the raw material, solves the disadvantage that the raw material can only rely on imported quartz sand, and improves the tightness between particles through high-temperature melting, reducing the number of bubbles, The product quality is improved, the production cycle is shortened, the production efficiency is improved, the energy is fully saved, and the production cost is reduced.

The invention relates to a high-voltage, ultrahigh-voltage and extra-high voltage switch transfer current device for busbar transfer load current operation. The high-voltage switch transfer current device comprises a horizontally arranged vacuum switch, a switch operating box and a steering square box between the horizontally arranged vacuum switch and the switch operating box, wherein a fixed contact and a moving contact of the vacuum switch are coaxially arranged opposite to each other in a shielding case of a vacuum arc extinction chamber, a plurality of thread grooves are arranged on a columnar contact of the fixed contact from the columnar face to the end face of the contact at equal intervals, and the contact end of the moving contact is provided with a slot matched with the columnar contact of the fixed contact; a brake separating spring crank arm, a braking crank arm and a roller crank arm are arranged on a control main shaft of an operating mechanism of the switch operating box. By the technical scheme, an isolating switch is endowed with the capability of switching on and off busbar transfer current during double-busbar changeover operation, and thus, the technical purpose that power-frequency low-voltage great-current transfer current arcs produced in the busbar transfer can be switched on and off by the moving contact and the fixed contact of a 100-1100 KV outdoor AC high-voltage isolating switch can be achived.

The present invention relates to a high-voltage vacuum circuit-breaker. It is composed of upper wiring flange, lower wiring flange, arc extinguishing unit, frame, supporting frame and control box. The frame is fixedly mounted on the supporting frame, the three-phase arc extinguishing unit is fixedly mounted on the frame, all the movable components of said arc extinguishing unit are mechanically connected on the spring mechanism in the control box, the arc extinguishing unit is characterized by that in its arc extinguishing chamber a vacuum tube is mounted, and its movable contact and static contact are mounted in the vacuum tube.

The invention belongs to a vacuum circuit breaker field and especially relates to a disc-type overlapping gyromagnetic longitudinal blowing vacuum arc extinguish chamber. The vacuum arc extinguish chamber comprises: a conducting rod (1), a contact cup (5), an iron core (7) and an electrode (4) which is connected to the contact cup (5). The contact cup (5) is fixedly matched with the conducting rod (1). The iron core (7) is placed in the contact cup (5). The contact cup (5) is provided with a plurality of circulation side slots with equal intervals. The iron core (7) is provided with the winding slots (6) with the equal intervals. More than two groups of the coaxial coil windings (8) are stacked into the winding slots (6) and the coaxial coil windings are staggered with a certain angle theta successively. According to the invention, through a strong force of a rotating magnetic field and simultaneously under an effect of a vertical magnetic field, an arc voltage can be reduced; arc columns are impelled to be uniformly distributed on an anode surface; arc energy release can be accelerated; a breaking capacity of the vacuum circuit breaker can be increased.

The invention discloses a -70 degrees centigrade low-temperature steel welding bar. The -70 degrees centigrade low-temperature steel welding bar comprises a welding core and a coating, the coating of the welding bar is composed of 44-54% of marble, 15-24% of fluorite, 3-6% of barium carbonate, 2-5% of quartz, 2-5% of dehydration potassium titanate, 0.5-1.5% of borax, 1-3% of manganese metal, 3-6% of atomized ferrosilicon, 1-3% of rare earth ferrosilicon, 3-6% of ferrotitanium, 0.5-1.0% of silicon calcium alloy, 6.0-8.0% of nickel powder and 0.2-1.0% of Teflon. The -70 degrees centigrade low-temperature steel welding bar is featured with low nickel content, less splashing, good molten bath fluidity, uniform slag cover, soft electric arc sound, beautiful weld joint appearance, easiness in sediment separation and good welding technique, the content of diffusible hydrogen in the weld joint metal is within 5ml / 100 g (mercury process), and this meets the standard super-low-hydrogen welding bar requirement.

The invention relates to a magnesium alloy micro-arc oxidation solution for carrying out micro-arc oxidation on a magnesium alloy to form a corrosion resistance layer on the surface of the magnesium alloy. The magnesium alloy micro-arc oxidation solution is characterized in that 1 L of the magnesium alloy micro-arc oxidation solution contains 1-9 g of caustic alkali, 2-12 g of a silicate, 1-9 g of an aluminate, 1-9 g of a fluoride, 0.3-1 g of a borate, and 2-6 mL of triethanolamine, wherein a solvent of the solution is water. The method for forming a corrosion resistance layer on the surface of a magnesium alloy by using the magnesium alloy micro-arc oxidation solution is characterized by comprising the following steps: preparing a magnesium alloy micro-arc oxidation solution, adding a certain mass of caustic alkali, a silicate, an aluminate, a fluoride, a borate and triethanolamine or hydrates of the compounds to water, carrying out stirring dissolving, adding water to achieve a certain volume, carrying out degreasing and washing on a magnesium alloy, placing the magnesium alloy in the micro-arc oxidation solution, carrying out micro-arc oxidation by adopting direct current pulse current, washing the magnesium alloy, and drying.

The present invention discloses a magnetization, decompression and cooling arc extinction line returning device of a coal mine well ventilator electric power case. The device comprises a fixed connection groove, a magnetization arc extinction device, a controller and an operation key. The fixed connection groove is inlaid and installed at the left end face of the magnetization arc extinction device. The air bag and a negative pressure cavity form a low pressure to allow an actuation block to be pasted to the surface of the electric power case for isolation from air and avoid that a lot of airpromotes arc recrudescence, the action force of a magnetic patch to arc electrons is employed to allow the arc to be close to an arc-shaped blocking plate gate, because a steel bar gate has a ferromagnetic feature to effectively absorb the arc and allow the arc to be stayed in a slit of an aperture and a laminated barb so as to reduce the arc voltage, a heat conductive pad and a condensation cavity are employed to absorb heat, the deformation of a balance rotation needle is employed to promote transmission of heat, The condensation and liquidation of distilled water in a water storage cavity are performed to consume and release the heat to reduce the arc temperature, prevent electrons from thermal ionization and allow the arc to be extinguished.