97 results about "Electric field stress" patented technology

It is intended to achieve the weight reduction, sliming, and downsizing of bushings, compatibility of types of bushings, and simplification of operating steps. A polymer bushing comprises a conductor draw-out bar (1) having a conductor insertion hole (1a) in the lower end, a hard insulation sleeve (2) installed around the outer periphery of the conductor draw-out bar (1), a polymer clad body (3) installed around the outer periphery of the insulation sleeve (2), and an electric field stress-control layer installed on the interface between the insulation sleeve (2) and the polymer clad body (3). The insulation sleeve (2) comprises a large-diameter insulation sleeve (2a) installed around the outer periphery of the lower region of the conductor draw-out bar (1), and a small-diameter insulation sleeve (2b) installed around the outer periphery of a portion of the conductor draw-out bar (1) excluding the front end. An embedment metal part (4) for electric field mitigation purposes is embedded in a portion of connection between the large-and small-diameter insulation sleeves (2a, 2b). Further, installed at the lower end of the large-diameter insulation sleeve (2a) is a cone-shaped receiving port (5) for receiving the stress cone (13) of a cable terminal (11), the receiving port (5) communicating with the conductor insertion hole (1a) in the conductor draw-out bar (1).

The invention relates to a three-dimensional power frequency electric field measurement method and a device capable of correcting the distortion of electric fields. In the method, three pairs of electrode boards of three capacitance type induced voltage sensors are respectively arranged vertical to the direction of a three-dimensional coordinate to form a three-dimensionally-combined capacitance type sensing voltage sensor probe; in a uniform electric field generating device, three induced voltage values and the electric fields corresponding to the three induced voltage values are measured when the directions of applied electric fields are consistent with an X axis, a Y axis and a Z axis; and then the distortion impact factors Lambada are obtained. The device consists of the three-dimensionally-combined capacitance type induced voltage sensor probe and a subsequent signal processing circuit. The method and the device improve the measurement accuracy of the sensors, collect remote measurement data, have the characteristics of small volume and light weight, and is convenient to install and carry; and the measurement accuracy error is about 5 percent. The method and the device are suitable for the measurement of the electric fields nearby transmission lines, transformer substations, high-voltage switch, living quarters and other neighboring areas.

The invention provides a wrapping and molding manufacturing method for a middle connector of a cross-linked polyethylene insulated power cable. The wrapping and molding manufacturing method comprises the following steps of step a, removing an outer sheath and a metal sleeve from a cable at two ends, and reserving a water-blocking buffer band; step b, performing cable preprocessing; step c, welding a wire core conductor; step d, recovering an inner semi-conductive layer: cleaning the port of the semi-conductive layer, and then wrapping the conductor with a semi-conductive layer wrapping band; step e, recovering an insulating layer; and step f, recovering an outer semi-conductive layer. The manufacturing method provided by the invention is convenient to operate; the manufactured middle connector and the cable body form an integrated structure; the electric field stress is uniform in distribution while the electric performance is stable; and the problem of a movable interface generated by different materials between the cable and the middle connector, and the problem of breakdown of the middle connector of the cable caused by partial electric field distortion of the insulating layer due to space accumulated charge are solved.

The invention discloses a multi-functional electrostatics experimental facility. The multi-functional electrostatics experimental facility includes a power supply, a controllable device, a first electrode plate, a second electrode plate and a casing, wherein the first electrode plate and the second electrode plate are connected with the power supply through wires and fixed on a support, the controllable device is used for providing uninterrupted charge particles, the charge particles can move in an electric field and form clearly seen motion tracks, the casing forms a closed environment so that the motion of the charge particles is not affected by the outside, and the power supply is an induction generator or a high voltage power supply. The multi-functional electrostatics experimental facility vividly and intuitively proves the existence of electric field forces and enables people to observe the motion and variation tracks of the charge particles in a uniform electric field.

The invention discloses a multi-iron-heterogeneous magnetic field sensor adjustable in measuring range and a measuring range adjusting method. The magnetic field sensor comprises a bottom metal electrode layer, a free layer, an isolation layer, a pinning layer and a top metal electrode layer which are arranged from bottom to top in sequence. The free layer is of a multi-iron-heterogeneous multi-layer structure and comprises a ferroelectric layer and a first ferromagnetic layer from bottom to top in sequence. The pinning layer is of a multi-layer structure and comprises a second ferromagnetic layer and a reverse ferromagnetic layer from bottom to top in sequence. A ferroelectric stress axis direction of the free layer is perpendicular to a magnetic moment direction of the pinning layer in horizontal projection. The measuring range adjusting method comprise the steps that: a measuring range switching voltage V is applied to the ferroelectric layer of the magnetic field sensor, the ferroelectric layer is enabled to generated an electric field stress, the first ferromagnetic layer is under the effect of the electric field stress, and a saturated magnetic field is changed, so that the measuring range of the magnetic field sensor is changed. The invention provides the multi-iron-heterogeneous magnetic field sensor simple in structure, small in size and convenient and flexible, and the measurement precision of the sensor in a low magnetic field is ensured.

The invention discloses a GIS equipment low-voltage conductor surface electric field intensity measurement method which belongs to the technical field of conductor surface electric field measurement. The structure of an electric field intensity measurement device is that a GIS equipment housing is fixed on a pedestal through a short support, a high-voltage conductor is supported in the center of the GIS equipment housing through a long support on the pedestal, and a wedge block is cut in the middle of the housing and is supported in situ with insulating material; the wedge block is connected with a resistor of 10 kilo ohms, the resistor is connected to the ground, and two ends of the resistor are connected with an amplifier circuit; the amplifier circuit is connected with a display; electric field intensity measurement is that high-voltage electricity of alternating current 220kV is applied to the high-voltage conductor, voltage signals of the two ends of the resistor are input to the amplifier circuit through a cable, and the reading of the electric field intensity is displayed on the display. Through electric field calculation and analysis of internal defects of GIS equipment, and through verification by a test, the GIS equipment low-voltage conductor surface electric field intensity measurement structure is of great significance to improving the internal insulating strength of the GIS and researching a relation between the internal defects and electric field intensity of the GIS equipment.

The invention discloses a grain coating method and a grain coating system for diamond wire saws. The grain coating method includes firstly, coating resin binders uniformly on surfaces of wire cores; secondly, applying negative charge to diamond grains, applying positive charge to the wire cores, enabling the diamond grains with the negative charge to move under action of electric field stress so as to implant the diamond grains into the resin binders on the core wires; and thirdly, curing the wire cores. In the grain coating method, the diamond grains with negative charge are implanted into the resin binders on the surface of the wire cores under action of the electric field stress so as to be uniformly distributed in the resin binders on the surfaces of the wire cores; implanted depth of the diamond grains in the resin binders is controlled by controlling the electric field stress of the diamond particles, the exposure rate of the diamond grains is then controlled, and accordingly cutting precision and cutting efficiency of diamond wire saws can be guaranteed and service lives thereof can be prolonged.

The invention provides a cross-linked polyethylene insulated cable insulation shielded isolation joint and a mold casting manufacturing process thereof. The cross-linked polyethylene insulated cable sequentially at least comprises a conductor cable core, an inner semi-conducting layer, a main insulating layer and an outer semi-conducting layer from the interior to exterior. The mold casting manufacturing process is characterized by comprising the following steps: stripping various layers at the cable end; welding conductor wire cores; restoring the main insulating layer; restoring the outer semi-conducting layer. The insulation shielded isolation joint comprises a stress control module. The manufacturing process disclosed by the invention is convenient to operate, and the manufactured insulation shielded isolation joint forms an integral structure with a cable body; electric stress distribution has stable electrical property, and the problem that cable insulation breakdown is caused by air-gap discharge on an insulated junction due to an active interface is generated by different materials between the cable and the stress control module is solved.

The invention belongs to the technical field of silicon carbide semiconductor device reliability test and relates to a SiC MOSFET device low-temperature stability evaluation test method. The method includes the following steps that: (1) a sample subjected to ECR nitrogen plasma passivation treatment is arranged into a probe station so as to be subjected to vacuumization and cooling; (2) C-V curvemeasurement is performed on the sample which has not been subjected to electric field stress; (3) C-V curve measurement is performed on the sample which has been subjected to electric field stress; (4) the drift quantity of a C-V curve before and after the application of the electric field stress is calculated; and (5) the influence of an ECR nitrogen plasma passivation process on device stabilityis evaluated. With the method of the invention adopted, the influence of movable charges and fixed charges on the stability of a SiC MOSTET device at low-temperature (80-300K) measurement can be eliminated; the separate passivation effects of the passivation process for an oxide layer trap and an interface trap are explored; and the charge number of the oxide layer trap and the charge number of the interface trap of the sample are calculated; and the low-temperature stability of the SiC MOSFET device can be evaluated.

The present invention discloses a resistivity measurement method based on vertical components of an electromagnetic field, belonging to the fields of earth sciences and physical geography. According to the method, under the excitation of a vertical incident plane to the vertical components of the electromagnetic field, the upper and lower sides of the boundary have inductive charges to cause a discontinuous electric field and changed vertical components of the field, the change appears at the upper and lower sides of the boundary so as to accurately reflect the positions of the upper and lowerboundaries of an object. The [Rho]EH T-inverted definition equation provided by the invention improves the resolution capability for the upper and lower interfaces of an electricity anomalous body due to direct reference of the discontinuity of the electric field on the upper and lower interfaces, and the resolution capability is only related to the electricity contrast ratio and the burying of the anomalous body and is not related to the size of the anomalous body so as to have important meaning for accurate detection of a small anomalous body in a superficial layer and the depth fine detection of the mineral resources in the engineering geophysics. The resistivity measurement method based on vertical components of an electromagnetic field is not better sensitive to the noise response inthe impedance Z than a Cagniard resistivity formula.

The invention discloses a crosslinked cable hot melting connector which is used for the protection layer connecting the cable and the cable arranged in the protection layer. The crosslinked cable hotmelting connector comprises a connecting group and a sheath group. The sheath group wraps outside the connecting group. The connecting group comprises a melting body which is used for connecting the internal conductor of the cable in a melting way, an internal semi-conductive layer which wraps outside the melting body and the conductor and an insulator. The internal semi-conductive layer is connected with a conductor shielding layer. The insulator wraps outside the internal semi-conductive layer. The insulator is externally connected with a cable insulating layer. According to the crosslinkedcable hot melting connector, the connecting group is used for connecting the cable and the sheath group is used for connecting the protection layer so as to realize double-layer protection; the connecting group can keep great conductivity so as to avoid cable breakdown caused by electric field stress concentration; and the shielding paint layer is arranged on the insulator so that the situation ofcable arc breakdown can be avoided, the external semi-conductive layer is connected with the galvanized copper mesh layer so that the whole cable insulating shielding is enabled to be completely andreliably recovered. The cable connector can be manufactured onsite so that operation is convenient, the cost is low and the cable connector is suitable for popularization.

The invention discloses a cellulose diacetate fibrous membrane and a preparing method thereof. Cellulose diacetate powder is dissolved in acetone/water or a mixed solvent of acetone/dichloromethane tobe prepared into a spinning solution, an electrostatic spinning technology is adopted, under the effect of electrostatic high-voltage electric field stress, the cellulose diacetate spinning solutionis drafted into fibers, and the fibers are cured on a receiver to form the fibrous membrane. According to the technical scheme, the preparing method is easy to operate, and the condition is easy to control. The fibers in the prepared cellulose diacetate fibrous membrane are thin, the diameter reaches the macron order, the surface of the fibers has a porous structure, the cross section of the fibers is flat, the specific area of the fibrous membrane is large, the adsorbing performance is excellent, and the cellulose diacetate fibrous membrane has a good application prospect in the fields like biological dressing, drug sustained release and tissue stent.

The invention provides a 500kV and below crosslinked polyethylene power cable intermediate connector and a manufacturing method thereof. The manufacturing method comprises the steps: stripping the twoends of a cable and enabling at least a cable conductor, a semi-conductive layer in the cable conductor and a cable main insulating layer to be exposed and fusing the cable conductors of the two ends; recovering the semi-conductive layer in the connector: mounting the semi-conductive pipe prefabricated from the polyethylene semi-conductive material to the connecting position of the cable conductors of the two ends and covering at least the cable conductor and the semi-conductive layer in the cable conductor and mounting a pressing mold on the semi-conductive pipe and heating the pressing mold; recovering the main insulating layer of the connector: and mounting a connector insulating forming mold and at least partially covering the cable main insulating layer and the semi-conductive layerin the connector by the mold and heating the mold after the polyethylene granular material fully fills in the mold. The invention also provides the intermediate connector manufactured by the method. The connector manufactured by the manufacturing method and the cable body form a consistent structure, and the electric property of the internal electric field stress distribution is equivalent to thatof the cable body.

A polymer bushing includes a conductor bar, a conductor insertion hole at a lower end, a rigid insulator around the outer circumference of the conductor bar and having a receiving port for a cable termination, a polymer covering around 4 the outer circumference of the insulator and a number of shades 4a formed separately along the longer dimension at the outer circumference. A large diameter part is provided above the conductor insertion hole which is in the vicinity of the lower end part of the insulator. A cylindrical shielding metal fitting is concentrically embedded together with the conductor bar in the large diameter part. An electric-field stress-control layer is provided at the interface between the large diameter part and the polymer covering.

The invention discloses a high-voltage pulse electric field sterilizing treatment chamber for monitoring the strength and temperature of electric fields on line. Two coaxial treatment chamber bodies are formed from two tubular high-voltage electrodes and tubular grounding electrodes, the two tubular high-voltage electrodes are partitioned by an insulating tube, and both ends of the tubular grounding electrodes are sheathed with insulated protecting sleeves, thereby a coaxial continuous high-voltage pulse electric field treatment chamber is formed. A Hall element and a linear digital temperature sensor are installed in the treatment chamber, signals are sent into a single-chip machine after conditioning, amplification and A/D conversion, and then each parameter is displayed by a liquid crystal display module. The high-voltage pulse electric field sterilizing treatment chamber can ensure the distributing uniformity of the electric fields and also improve the flow characteristics of liquid materials to improve the treatment flow, and avoids the occurrence of dead zones, and the treatment effect is obviously improved; and moreover, the high-voltage pulse electric field sterilizing treatment chamber quantitatively monitors the strength and temperature values of the electric fields in the treatment chamber on line in real time and can provide data support for the simulated modeling of a treatment system.

The invention discloses an ohm law-based evaluation method of soil ionization critical electric field intensity. The evaluation method comprises following steps of selecting a to-be-tested region and measuring resistivity, dielectric constant and magnetic permeability of soil in the region; establishing an to-the-ground discharging loop; arranging a test electrode; acquiring test voltage; converting the test voltage into electric field intensity; determining ionization time of the soil according to through of the function K; and obtaining the maximum changing curve of the electric filed intensity in the soil and determining the soil ionization critical electric field intensity by combining the precise ionization time of the soil. According to the invention, by directly testing the to-be-tested region of the soil, natural features of the soil will not be damaged; the obtained soil ionization critical electric field intensity is completely the same as the soil ionization critical electric field intensity in the natural environment; and high precision measurement can be realized.

The invention discloses an applied electric field-induced friction device and a testing method thereof. The applied electric field-induced friction device comprises a pedestal, an upper friction pairscomposed of a conductive clamp and a metal friction piece arranged at the bottom of the conductive clamp, a lower friction pairs composed of a carbon based film and a plate electrode arranged at thebottom of the carbon based film, and a motion unit and an adjusting unit arranged at the pedestal, a strain beam, a loading unit, a cantilever beam, and a power source which are arranged at the pedestal. The motion unit pushes the lower friction pairs to move, a strain sheet is arranged at the strain beam, the front bottom of the cantilever beam is connected with the upper friction pairs, the topof the front end of the cantilever beam is connected with the loading unit, the rear end of the cantilever beam is connected with the front end of the strain beam, the adjusting unit is connected withthe rear end of the strain beam, the position of the upper friction pairs is adjusted, a positive pole of the power source is electrically connected with the conductive clamp, a negative pole of thepower source is electrically connected with a plate electrode, so that the friction coefficient between the metal friction piece and the carbon based film is reduced.

The invention discloses an organic electric field distributed control agent migration-based self-adaptive control electric field method, and belongs to the technical field of high-voltage insulation.A method which can be used for effectively suppressing distortion of an electric field in an insulation structure and homogenizing electric field distribution is provided. The working principle of themethod is in a way that a few amount of low molecular polymer containing benzene ring and an ether bond functional group or a non-free-radical scavenger voltage stabilizer is added into an insulationpolymer, the field-enhanced non-linear conductivity and polarization of a composite material can be improved, polar molecules migrate to form self-adaptive gradient distribution under driving of an electric field gradient force of a non-uniform electric field, so that the conductivity and the polarization of a high electric field region are improved, and the electric field intensity of the high electric field region is reduced. A control agent added into an insulation system is wide in source, is economic and available and has good compatibility with a polymer matrix, a homogenization effecton electric field distortion caused by any factor is achieved, and the control agent has favorable self-adaptive capability of controlling the electric field.