摘要:
The invention relates to a method and apparatus for recognizing a standstill condition when restarting a power converter-fed AC motor without a tachometer generator. According to an embodiment of the invention, a standstill recognition method includes first and second active phases decoupled by a passive phase. In each phase, time characteristics of the orthogonal current components of a measured motor current are recorded, and the energy component of current from the second active phase is further evaluated to generate an average value. This generated average value and an upper range value are then compared to a limiting value, which will be exceeded when the AC motor is at a standstill. Thus, through application of a current measurement and a simple evaluation, one can quickly determine the actual state of the power converter-fed AC motor when restarting.
摘要:
An optoelectronic component includes a carrier element. At least two elements are arranged in an adjacent fashion on a first side of the carrier element. Each element has at least one optically active region for generating the electromagnetic radiation. The optoelectronic component has an electrically insulating protective layer arranged at least in part on a surface of the at least two adjacent elements which lies opposite the first side. The protective layer, at least in a first region arranged between the at least two adjacent elements, at least predominantly prevents a transmission of the electromagnetic radiation generated by the optically active regions.
摘要:
An optoelectronic module has at least one carrier with at least one contact location. A semiconductor chip emitting radiation includes a first contact surface and a second contact surface. An electrically insulating layer has a first and a second recess. The first contact surface is disposed on the side of the semiconductor chip emitting radiation facing away from the carrier. The electrically insulating layer is applied at least in places to the carrier. The semiconductor chip includes the first recess in the area of the first contact surface and the second recess in the area of the contact location. A electrically conductive conductor structure is disposed on the electrically insulating layer. The first contact surface electrically contacts the contact location of the carrier. The electrically insulating layer is formed predominately from a ceramic material.
摘要:
In a chromatograph, a separation column is disposed between an injection system and a detector. The separation column includes a bundle of capillaries which are formed of carbon nanotubes with a typical diameter of 0.5 nm to 5 nm and may number in the several hundreds.
摘要:
A film, based on polyimide or epoxy, is laminated onto a surface of a substrate under a vacuum, so that the film closely covers the surface and adheres thereto. Contact surfaces to be formed on the surface are uncovered by opening windows in the film. A contact is established in a plane manner between each uncovered contact surface and a layer of metal. This establishes a large-surface contact providing high current density for power semiconductor chips.
摘要:
An optoelectronic component includes a carrier element. At least two elements are arranged in an adjacent fashion on a first side of the carrier element. Each element has at least one optically active region for generating the electromagnetic radiation. The optoelectronic component has an electrically insulating protective layer arranged at least in part on a surface of the at least two adjacent elements which lies opposite the first side. The protective layer, at least in a first region arranged between the at least two adjacent elements, at least predominantly prevents a transmission of the electromagnetic radiation generated by the optically active regions.
摘要:
A film, based on polyimide or epoxy, is laminated onto a surface of a substrate under a vacuum, so that the film closely covers the surface and adheres thereto. Contact surfaces to be formed on the surface are uncovered by opening windows in the film. A contact is established in a plane manner between each uncovered contact surface and a layer of metal. This establishes a large-surface contact providing high current density for power semiconductor chips.