# US 2019/0172668 A1 · Gas-insulated high-voltage switching device with improved main nozzle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0172668 A1 - Document ID: US20190172668A1 - Status: Published application - Kind: A1 - Application number: 16/253,367 - Filed: 2019-01-22 - Published: 2019-06-06 - Earliest claimed: 2016-07-21 - Assignees: ABB Power Grids Switzerland AG - Applicants: ABB Schweiz AG - Inventors: Bernardo Galletti; Manuel Gotti; Markus Bujotzek; Martin Seeger - Web page: https://patentgrep.com/patent/US20190172668A1 ## CPC - H01H 33/7023: {characterised by an insulating tubular gas flow enhancing nozzle (H01H33/7038 takes precedence)} - H01H 33/91: the arc-extinguishing fluid being air or gas - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) ## Abstract A gas-insulated high-voltage switching device which includes an arcing contact arrangement having a first arcing zone member and a second arcing zone member that are movable relative to one another along an axis. An auxiliary nozzle surrounds at least a part of a second arcing contact unit and has an auxiliary nozzle throat having an axial extension and allowing passage at least of an end of the first arcing contact unit. A main nozzle throat has an axial extension sideways of the auxiliary nozzle throat and allows passage at least of the end of the first arcing contact unit. A cross-sectional area of the main nozzle throat is substantially decreasing in the direction away from the auxiliary nozzle throat so as to form a substantially converging duct for the flow of an arc-extinguishing gas. ## Claims ### Claim at position 1 1-19. (canceled) ### Claim 20 A gas-insulated high-voltage switching device, comprising: an arcing contact arrangement comprising a first arcing zone member and a second arcing zone member, wherein the first arcing zone member and the second arcing zone member are movable relative to one another along an axis (B), wherein the first arcing zone member comprises a first arcing contact unit; and wherein the second arcing zone member comprises: a second arcing contact unit configured to receive the first arcing contact unit; an auxiliary nozzle surrounding at least a part of the second arcing contact unit and having an auxiliary nozzle throat which has an axial extension and allows passage at least of an end of the first arcing contact unit; a main nozzle surrounding at least a part of the auxiliary nozzle, and having a main nozzle throat, which has an axial extension sideways of the auxiliary nozzle throat and allows passage at least of the end of the first arcing contact unit, a cross-sectional area of the main nozzle throat is substantially decreasing in the axial direction away from the auxiliary nozzle throat so as to form a converging flow duct for a flow of an arc-extinguishing gas, wherein the converging flow duct of the main nozzle throat has a length L in the axial direction in a range of 15 mm to 80 mm, and the main nozzle throat has an aperture angle a in a range from more than 0° to at most 15° and a shape of the main nozzle throat is frusto-conical. ### Claim 21 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein a larger cross-sectional area of the main nozzle throat is at a first end of the main nozzle throat adjacent to the heating channel and a narrower cross-sectional area of the main nozzle throat is at a second end of the main nozzle throat remote from the heating channel. ### Claim 22 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the substantially converging flow duct of the main nozzle is converging in downstream direction of the arc-extinguishing gas. ### Claim 23 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the main nozzle throat has a largest cross-sectional area Amax at a first end of the main nozzle throat towards the auxiliary nozzle throat, and has a smallest cross-sectional area Amin at a second end of the main nozzle throat away from the auxiliary nozzle throat. ### Claim 24 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the main nozzle throat has an n-fold discrete rotational symmetry or a continuous rotational symmetry with respect to the axis (B). ### Claim 25 (depends on 22) The gas-insulated high-voltage switching device according to claim 22, wherein an axial position of a stagnation point of the arc-extinguishing gas is located upstream of the substantially converging flow duct of the main nozzle. ### Claim 26 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the main nozzle throat is continuously rotational symmetric with respect to the axis (B), has a largest cross-sectional area Amax=π Rmax2 with Rmax=maximal radius of the main nozzle throat, at a first end of the main nozzle throat towards the auxiliary nozzle throat, and has a smallest cross-sectional area Amin=π Rmin2 with Rmin=minimal radius of the main nozzle throat at a second end of the main nozzle throat away from the auxiliary nozzle throat, wherein Rmax and Rmin are radii measured from the axis (B). ### Claim 27 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein α=arctan((Rmax−Rmin)/L) with Rmin=minimal radius and Rmax=maximal radius of the main nozzle throat with the radii being measured from the axis (B), and L is the length of the main nozzle throat along the axis (B), with preferably Rmax, Rmin or a mean radius of the main nozzle throat or of the substantially converging duct lying in a range from 5 mm to 20 mm. ### Claim 28 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the main nozzle throat is strictly monotonously converging. ### Claim 29 (depends on 28) The gas-insulated high-voltage switching device according to claim 28, wherein the cross-sectional area of the main nozzle throat decreases quadratically along the length of the main nozzle throat. ### Claim 30 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the main nozzle comprises a diffuser portion adjacent to and downstream of the main nozzle throat, the diffuser portion being divergent in the direction away from the auxiliary nozzle throat, thereby forming a diverging duct for the flow of an arc-extinguishing gas. ### Claim 31 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, comprising a pressure volume, wherein the second arcing zone member comprises a heating channel formed between the main nozzle and the auxiliary nozzle, the heating channel being in fluid communication on one end with the pressure volume and on the other end with a part of an arcing zone (Z) lying between the auxiliary nozzle throat and the main nozzle throat. ### Claim 32 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the first arcing contact unit is an arcing contact pin, and the second arcing contact unit is an arcing contact tulip. ### Claim 33 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein an interior surface of the main nozzle has a surface roughness Rz smaller than 20 μm at least in the main nozzle throat. ### Claim 34 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the gas-insulated high-voltage switching device is a gas-insulated high-voltage self-blast circuit breaker. ### Claim 35 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the convergent profile of the insulating nozzle throat helps to have a higher flow velocity at a second end of the nozzle throat away from the auxiliary nozzle throat, which higher flow velocity supports a more effective removal of the hot gas that resides in the region adjacent to an end of the contact pin after the arc has been extinguished thermally. ### Claim 36 (depends on 20) A method of manufacturing a gas-insulated high-voltage switching device according to claim 20, the method comprising: controlled shaping of the main nozzle throat of the main nozzle of the gas-insulated high-voltage switching device according to claim 20 to form the substantially converging flow duct for the flow of the arc-extinguishing gas. ### Claim 37 (depends on 36) The method according to claim 36, wherein controlled shaping of the main nozzle throat comprises sintering the main nozzle and machining it. ### Claim 38 A method of operating a gas-insulated high-voltage switching device, the method comprising: providing a gas-insulated high-voltage switching device, comprising: an arcing contact arrangement comprising a first arcing zone member and a second arcing zone member, wherein the first arcing zone member and the second arcing zone member are movable relative to one another along an axis (B), wherein the first arcing zone member comprises a first arcing contact unit; and wherein the second arcing zone member comprises: a second arcing contact unit configured to receive the first arcing contact unit; an auxiliary nozzle surrounding at least a part of the second arcing contact unit and having an auxiliary nozzle throat which has an axial extension and allows passage at least of an end of the first arcing contact unit; a main nozzle surrounding at least a part of the auxiliary nozzle, and having a main nozzle throat, which has an axial extension sideways of the auxiliary nozzle throat and allows passage at least of the end of the first arcing contact unit, a cross-sectional area of the main nozzle throat is substantially decreasing in the axial direction away from the auxiliary nozzle throat so as to form a converging flow duct for a flow of an arc-extinguishing gas, wherein the converging flow duct of the main nozzle throat has a length L in the axial direction in a range of 15 mm to 80 mm, and the main nozzle throat has an aperture angle a in a range from more than 0° to at most 15° and a shape of the main nozzle throat is frusto-conical; performing a low short-circuit current switching operation, wherein the switching current is smaller than 0.3 times the rated short-circuit current, particularly wherein the rated short-circuit current is between 31.5 kA and 80 kA. ### Claim 39 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein a larger cross-sectional area of the main nozzle throat is at a first end of the main nozzle throat adjacent to the heating channel and a narrower cross-sectional area of the main nozzle throat is at a second end of the main nozzle throat remote from the heating channel, in particular adjacent to a main nozzle diffuser portion. ### Claim 40 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the main nozzle throat has a largest cross-sectional area Amax at a first end of the main nozzle throat towards the auxiliary nozzle throat, and has a smallest cross-sectional area Amin, in particular Amin=π Rmin2 with Rmin=minimal radius of the main nozzle throat, at a second end of the main nozzle throat away from the auxiliary nozzle throat. ### Claim 41 (depends on 20) The gas-insulated high-voltage switching device according to claim 20, wherein the gas-insulated high-voltage switching device is a gas-insulated high-voltage self-blast circuit breaker, preferably a double-motion self-blast circuit breaker.