Abstract: A method controls a power converter in which a target value of a control parameter is limited by at least one limiting value. The method is characterized in that the at least one limiting value is determined dynamically over time as a function of a power converter temperature. A power converter system having a control device is provided and configured to carry out the method.

Abstract: An optical coupler is described herein. The optical coupler includes at least one optical coupler unit. The at least one optical coupler includes an optical coupler entrance face and an optical coupler exit face. The optical coupler entrance face is configured to face, and receive light emitted by, at least one LED during operation. The optical coupler exit face is shaped as a Fresnel lens with a focal point at or behind a light emitting area of the at least one LED and is configured to face a lightguide entrance face of a slab lightguide. The optical coupler exit face has dimensions that match at least a part of the lightguide entrance face. The optical coupler entrance and exit faces are configured to refract light emitted by the at least one LED during operation.

Abstract: A screen printing form (1, 1?) for use in screen printing, in particular for producing a metallic contact structure of a photovoltaic solar cell, having a woven screen printing fabric (1b) with a plurality of elongate woven fabric elements, which are arranged in a first element direction and a second element direction perpendicular thereto, and a stencil (1c), arranged on the woven screen printing fabric (1b) that has at least one opening formed as straight channel with a channel width BK. The woven fabric elements have a spacing AF in the first element direction and a spacing which deviates by less than 5% from AF in the second element direction, and the woven fabric elements have a diameter DG in the first element direction and a diameter which deviates by less than 5% from DG in the second element direction. A screen printing device and screen printing form are also provided.

Abstract: A printing form for producing a structure of an electronic component, in particular a photovoltaic solar cell, having a screen frame and a screen, which is in the form of a sheet-like textile and has a multiplicity of elongate screen elements. The screen is arranged in the screen frame and the screen has at least one printing region which a printing paste can permeate and at least one barrier region which the printing paste cannot permeate. The elongate screen elements are made from glass fiber, carbon fiber and/or carbon nanotubes.

Abstract: An optical coupler is described herein. The optical coupler includes at least one optical coupler unit. The at least one optical coupler includes an optical coupler entrance face and an optical coupler exit face. The optical coupler entrance face is configured to face, and receive light emitted by, at least one LED during operation. The optical coupler exit face is shaped as a Fresnel lens with a focal point at or behind a light emitting area of the at least one LED and is configured to face a lightguide entrance face of a slab lightguide. The optical coupler exit face has dimensions that match at least a part of the lightguide entrance face. The optical coupler entrance and exit faces are configured to refract light emitted by the at least one LED during operation.

Abstract: A screen printing form (1, 1?) for use in screen printing, in particular for producing a metallic contact structure of a photovoltaic solar cell, having a woven screen printing fabric (1b) with a plurality of elongate woven fabric elements, which are arranged in a first element direction and a second element direction perpendicular thereto, and a stencil (1c), arranged on the woven screen printing fabric (1b) that has at least one opening formed as straight channel with a channel width BK. The woven fabric elements have a spacing AF in the first element direction and a spacing which deviates by less than 5% from AF in the second element direction, and the woven fabric elements have a diameter DG in the first element direction and a diameter which deviates by less than 5% from DG in the second element direction. A screen printing device and screen printing form are also provided.

Abstract: A method controls a power converter in which a target value of a control parameter is limited by at least one limiting value. The method is characterized in that the at least one limiting value is determined dynamically over time as a function of a power converter temperature. A power converter system having a control device is provided and configured to carry out the method.

Abstract: In a method for monitoring a high-voltage DC transmission the following are predefined: an amperage threshold value for an amperage of the high-voltage DC transmission, at least one interval length for time intervals and, for each predefined interval length, a change threshold value for a change in the amperage averaged over time intervals of the interval length. The amperage for each terminal of the high-voltage DC transmission is determined, and a change in the amperage averaged over time intervals of the interval length is determined for each predefined interval length. A DC error is determined if the magnitude of the amperage of at least one terminal is greater than the amperage threshold value or if, for an interval length, the magnitude of the averaged change in the amperage of at least one terminal is greater than the change threshold value predefined for the interval length.

Abstract: In a method for monitoring a high-voltage DC transmission the following are predefined: an amperage threshold value for an amperage of the high-voltage DC transmission, at least one interval length for time intervals and, for each predefined interval length, a change threshold value for a change in the amperage averaged over time intervals of the interval length. The amperage for each terminal of the high-voltage DC transmission is determined, and a change in the amperage averaged over time intervals of the interval length is determined for each predefined interval length. A DC error is determined if the magnitude of the amperage of at least one terminal is greater than the amperage threshold value or if, for an interval length, the magnitude of the averaged change in the amperage of at least one terminal is greater than the change threshold value predefined for the interval length.

Abstract: A hydraulic cylinder unit (1) having a hydraulic cylinder (2), a piston (3) which can be moved in the hydraulic cylinder (2), and a servo valve (7). The piston (3) separates working volumes (5A, 5B) of the hydraulic cylinder unit (1) from one another. The servo valve (7) is connected to a hydraulic pump (8), a tank (9), and the working volumes (5A, 5B). The servo valve (7) is supplied with a pump pressure (pP) via the hydraulic pump (8). The tank (9) has a tank pressure (pT). The servo valve (7) is adjusted to a defined valve position (y). A piston position (z) of the piston (3) in the hydraulic cylinder (2) and working pressures (pA, pB) which are applied to the working volumes (5A, 5B) are detected.

Abstract: A hydraulic cylinder unit (1) having a hydraulic cylinder (2), a piston (3) which can be moved in the hydraulic cylinder (2), and a servo valve (7). The piston (3) separates working volumes (5A, 5B) of the hydraulic cylinder unit (1) from one another. The servo valve (7) is connected to a hydraulic pump (8), a tank (9), and the working volumes (5A, 5B). The servo valve (7) is supplied with a pump pressure (pP) via the hydraulic pump (8). The tank (9) has a tank pressure (pT). The servo valve (7) is adjusted to a defined valve position (y). A piston position (z) of the piston (3) in the hydraulic cylinder (2) and working pressures (pA, pB) which are applied to the working volumes (5A, 5B) are detected.

Abstract: The present invention relates to an optical lens package, said lens package (1) having a lens body comprising a base (7), a central surface section (4) opposite to the base (7) and a peripheral surface section extending between the central surface section (4) and the base (7). The central surface section (4) is centered with respect to the optical axis (5) of the lens package (1) and has a convex shape in at least a first cross-sectional plane including the optical axis (5). At least a portion (6) of the peripheral surface section has a concave shape in said first cross-sectional plane. With such a design of the optical lens package (1) in addition to a central collimated light bundle with high luminous flux also side visibility is achieved by means of the concave portion (6) up to a high angle with respect to the optical axis (5). This side visibility is achieved without additional optics thus lowering the production costs of such an optical system compared to a solution using additional optics.

Abstract: The invention discloses a method for the preparation of 1-methyl-3-(trifluoromethyl)-1H-pyrazol-5-ol with high selectivity with respect to the content of the isomer 1-methyl-5-(trifluoromethyl)-1H-pyrazol-3-ol.

Abstract: The present invention relates to an optical lens package, said lens package (1) having a lens body comprising a base (7), a central surface section (4) opposite to the base (7) and a peripheral surface section extending between the central surface section (4) and the base (7). The central surface section (4) is centered with respect to the optical axis (5) of the lens package (1) and has a convex shape in at least a first cross-sectional plane including the optical axis (5). At least a portion (6) of the peripheral surface section has a concave shape in said first cross-sectional plane. With such a design of the optical lens package (1) in addition to a central collimated light bundle with high luminous flux also side visibility is achieved by means of the concave portion (6) up to a high angle with respect to the optical axis (5). This side visibility is achieved without additional optics thus lowering the production costs of such an optical system compared to a solution using additional optics.

Abstract: The invention relates to a tube bundle heat exchanger having a plurality of tube windings (1) through which a heat transfer medium flows in parallel. The tube windings start from a common inlet chamber (2) for the heat transfer medium and open into a common outlet chamber (3). Each tube winding comprises an alternating sequence of tube sections (6) running alternately in two planes parallel to each other, and tube bends (7) connecting same, wherein within each of the two planes four or more pipe sections extend disposed side by side or parallel to each other, and wherein the pipe bends are designed to have a change of direction through 180° with respect to an associated bend axis and have the same bend radii.