32results about How to "Reduce step voltage" patented technology

The invention discloses a grounding method of reducing local impact grounding resistance of a power plant and a substation, which comprises an inner-layer annular horizontal grounding body, an outer-layer annular horizontal grounding body, a horizontal connection body and a vertical grounding body. According to the grounding method of reducing local impact grounding resistance of a power plant and a substation, local impact grounding resistance of a power plant and a substation can be reduced, diffusion of local impact grounding current is enhanced, a grounding grid local electric potential can be prevented from rising, and safety of primary and secondary devices such as a transformer can be protected; electric potential and electric field distribution around a grounding electrode can be improved, the step voltage, device contact voltage values and the like can be reduced; and the grounding method of reducing local impact grounding resistance of a power plant and a substation has the advantages of wide application range, convenient construction, corrosion resistance, safety and reliability, and long service life.

The present invention discloses a novel step voltage calculation method based on circular ring-shaped DC power transmission earth electrode different buried depths. The method comprises the followingtwo situations of (1) analyzing the potential distribution that the homogeneous medium circular ring-shaped earth electrodes are not buried at the equal depth to obtain a calculation expression of a step voltage on an earth surface; (2) analyzing the potential distribution that the horizontal dual-layer medium circular ring-shaped earth electrodes are not buried at the equal depth to obtain a calculation expression of the step voltage on the earth surface; utilizing a MALTAB software to simulate to obtain the results and the influence of different earth electrode ring numbers and different buried depths on a surface potential, thereby demonstrating that the method provided by the present invention enables the step voltage to be reduced. The present invention creatively provides the thoughtthat the dual-circular ring-shaped earth electrodes are not buried at the equal depth, the calculation is simple, and the operation speed is fast.

The invention provides a grounding electrode insulation shielding structure used for reducing the pace voltage of grounding electrodes, which comprises the grounding electrode that is arranged under the ground surface, a coke bed covering the grounding electrode, and an insulating barrier that is arranged between the grounding electrode and the ground surface and is used for preventing the electric current from flowing towards superficial layer soil and forcing the electric current from flowing towards submerged soil, thus reducing the pace voltage of the ground surface. According to the structure, the maximum pace voltage is reduced in a way of saving more instruction funds under the condition that the size of the grounding electrode is not increased, and land occupying area is not enlarged.

A microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device relates to the technical field of arc extinguishing and harmonic eliminating of an electric power system. The microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device comprises a high-voltage current-limiting fuse, a voltage transformer, a three-phase combined type overvoltage protector, a vacuum contactor, a microcomputer arc-extinguishing controller, a high-voltage fuse and a zero-sequence current transformer, wherein three-phase ports of the three-phase combined type overvoltage protector are connected with a three-phase high-voltage isolation switch; a grounding terminal of the three-phase combined type overvoltage protector is connected with the voltage transformer and then grounded; the high-voltage fuse is connected in series between three-phase ports of the voltage transformer and the three-phase high-voltage isolation switch; a voltage transformer control terminal of the microcomputer arc-extinguishing controller is connected with the voltage transformer; a vacuum contactor control terminal of the microcomputer arc-extinguishing controller is connected with the vacuum contactor; three-phase ports of the high-voltage current-limiting fuse are respectively connected with the three-phase high-voltage isolation switch, while the other ends of the high-voltage current-limiting fuse are connected with the vacuum contactor; a grounding terminal of the vacuum contactor is grounded; and the zero-sequence current transformer is arranged between the grounding terminal of the vacuum contactor and a grounding point. The overvoltage-protecting device is high in action speed and capable of arc-extinguishing and harmonic-eliminating.

A microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device relates to the technical field of arc extinguishing and harmonic eliminating of an electric power system. The microcomputer arc-extinguishing, harmonic-eliminating and overvoltage-protecting device comprises a high-voltage current-limiting fuse, a voltage transformer, a three-phase combined type overvoltage protector, a vacuum contactor, a microcomputer arc-extinguishing controller, a high-voltage fuse, and a zero-sequence current transformer, wherein three-phase ports of the three-phase combined type overvoltage protector are respectively connected with a three-phase high-voltage isolation switch; a grounding terminal of the three-phase combined type overvoltage protector is connected with the voltage transformer and then grounded; the high-voltage fuse is connected in series between three-phase ports of the voltage transformer and the three-phase high-voltage isolation switch; a voltage transformer control terminal of the microcomputer arc-extinguishing controller is connected with the voltage transformer; a vacuum contactor control terminal of the microcomputer arc-extinguishing controller is connected with the vacuum contactor; three-phase ports of the high-voltage current-limiting fuse are respectively connected with the three-phase high-voltage isolation switch, while the other ends of the high-voltage current-limiting fuse are connected with the vacuum contactor; a grounding terminal of the vacuum contactor is grounded; and the zero-sequence current transformer is arranged between the grounding terminal of the vacuum contactor and a grounding point. The overvoltage-protecting device is high in action speed and capable of arc-extinguishing and harmonic-eliminating.

The invention relates to a microcomputer arc harmonic elimination and overvoltage protection device and belongs to the arc harmonic elimination field of an electrical power system. The protection device comprises a high voltage current limit fuse, a voltage transformer, a three-phase combined overvoltage protection device, a vacuum contactor, a microcomputer arc elimination controller, a high voltage fuse and a zero sequence current transformer, wherein three-phase ports of the three-phase combined overvoltage protection device are respectively connected with a three-phase high voltage isolation switch, a ground end is connected with the voltage transformer and is then in ground connection, the high voltage fuse is connected between three-phase ports of the voltage transformer and the three-phase high voltage isolation switch, a voltage transformer control end of the microcomputer arc elimination controller is connected with the voltage transformer, a vacuum contactor control end is connected with the vacuum contactor, three-phase ports of the high voltage current limit fuse are respectively connected with the three-phase high voltage isolation switch, the other end is connected with the vacuum contactor, a ground end of the vacuum contact is in ground connection, and the zero sequence current transformer is arranged between the ground end and a ground point. The protection device is advantaged in that the motion speed is fast, and arc harmonic elimination effects can be realized.

The invention relates to the field of a lightning-protection grounding geographic pole and particularly relates to a graphite lightning-protection grounding module and a preparation method thereof. The graphite lightning-protection grounding module is made from graphite powder, granular graphite and asphalt. The preparation method comprises the steps of material preparing, kneading, blank preparing, roasting, post processing, and the like. The graphite lightning-protection grounding module disclosed by the invention is low in electrical resistivity, relatively high in mechanical strength, resistant to corrosion and long in service life.

The invention discloses an arc extinction, harmonic elimination and overvoltage protection device of a microcomputer, and relates to the technical field of arc extinction and harmonic elimination of a power system. The arc extinction, harmonic elimination and overvoltage protection device comprises high-voltage current-limiting fuses, a voltage transformer, a three-phase combined overvoltage protector, vacuum contactors, a microcomputer arc extinction controller, high-voltage fuses and a zero sequence current transformer, wherein three phase ports of the three-phase combined overvoltage protector are separately connected with three phase high-voltage isolation switches, a ground end is connected with the voltage transformer and then is grounded, the high-voltage fuses are connected in series between three phase ports of the voltage transformer and the three phase high-voltage isolation switches, a voltage transformer control end of the microcomputer arc extinction controller is connected with the voltage transformer, vacuum contactor control ends are connected with the vacuum contactors, the three phase ports of the high-voltage current-limiting fuses are separately connected with the three phase high-voltage isolation switches, the other ends of the high-voltage current-limiting fuses are connected with the vacuum contactors, vacuum contactor ground ends are grounded, and the zero sequence current transformer is arranged between the ground end and a ground point. The overvoltage protection device has the advantages of fast action speed and can be used for arc extinction and harmonic elimination.

Electric resistance stone materials and a method for manufacturing the same are provided to reduce a step voltage and a contact voltage and to maintain high electric resistance for a long period of time by securing water repellent characteristic and non-repairing characteristic based on a silicon water repellent layer. A method for manufacturing electric resistance stone materials(1) includes the following: A composition containing (A) components and (B) components is prepared. The composition is attached to the surface of dry natural stone(2) of 5-50mm diameters. A heat treating process is implemented at a temperature between 50 and 250 degrees Celsius. The (A) components are organopolysiloxane containing at least three Si-H bonds in one molecule, and the (B) components are platinum catalysts.