4 results about "Surface breakdown" patented technology

The invention provides a method for calculating the surface breakdown field intensity of a high-voltage direct-current insulator. The method comprises the following steps: 1) calculating a direct-current air gap discharge field intensity expected value Ed; 2) designing the specification of the tested insulation sample according to the Ed obtained in the step 1); 3) loading the tested insulation sample into a test device for breakdown test to obtain a lightning impulse voltage and direct current voltage superposed breakdown voltage U0; and 4) calculating the superposition breakdown field strength E of the lightning impulse voltage and the direct-current voltage of the insulation sample according to the U0. The complete method for calculating the superposition breakdown field intensity of the lightning impulse voltage and the direct-current voltage is provided, the specification of the tested insulation sample is reasonably determined based on the expected value of the negative polarity direct-current air gap discharge field intensity, then the field intensity is calculated, and the field intensity design reference of the direct-current insulator is provided for the design of the high-voltage direct-current insulator.

The invention discloses a surface breakdown test device for a high-voltage insulator. The surface breakdown test device comprises a cylinder and an insulating support structure, an insulator is arranged in the cylinder body and separates an air chamber in the cylinder body; an end cover is arranged at the end part of the cylinder body; the insulating pillar structure comprises a first conductor, an insulating pillar and a second conductor. The first conductor is connected with the insulator, the second conductor is connected with the end cover, and the insulating pillar is arranged between the first conductor and the second conductor. The insulating pillar structure in the test device is convenient to disassemble and can be repeatedly used.

The utility model relates to a test tool for gas insulation criterion research, and belongs to the technical field of test tools, the test tool comprises a test box body and a capacitive high-voltage bushing communicated with the test box body, and the test box body comprises a shell, an upper electrode, a lower electrode and an insulation cushion block. According to the application, the test is relatively convenient, the surface breakdown voltage characteristic and the breakdown path of the solid insulation under the specified pressure can be obtained, and the air gap breakdown characteristic between the two electrodes (after the insulating cushion block between the electrodes is taken out) can be obtained. And design regulations are provided for turn-to-turn insulation design, main insulation design and lead-to-ground insulation design of the gas insulation transformer. The lower electrode of the test tool is designed to be a movable electrode, breakdown voltage values under different distances can be obtained by adjusting the distance between the lower electrode and the upper electrode, and a breakdown voltage curve can be drawn.

The application relates to a terminal structure and a preparation method of a power device. In a terminal region, a depletion stop ring is arranged in the direction of a second conductive type VLD region of a main junction, wherein the depletion stop ring is distributed in the terminal region at least in the second conductive type VLD region; for any depletion stop ring, a plurality of interval distributed depletion stop grooves are arranged, and the groove bottom of the depletion stop groove is below the second conductive type VLD region; for any depletion stop groove, in-groove conductive polysilicon filled in the depletion stop groove and in-groove low dielectric insulator covering the inner wall of the depletion stop groove are arranged, and the in-groove conductive polysilicon is insulated and separated from the inner wall of the depletion stop groove through the in-groove low dielectric insulator. The application can effectively avoid the surface breakdown of the VLD region, eliminate the influence of the periphery of the main junction and the deviation of the injection dose of a production line machine on the breakdown voltage, and improve the reliability of the terminal.