Abstract: A method for generating a series of ultra-thin sections of a microscopic sample is provided. The method includes detaching the sections from the sample using an ultramicrotome. The sections detached from the sample are made to float on a liquid surface and thereafter are transferred onto a solid carrier element. The method also includes determining, for at least one of the sections detached from the sample, a position and an orientation on the solid carrier element by monitoring the placement of the sections onto the solid carrier element using a monitoring system comprising a camera, and obtaining monitoring data.

Abstract: A leading-edge device for an aerodynamic component is disclosed having a first skin element having an inner surface and an aerodynamic outer surface, and further includes a second skin element having an inner surface and an aerodynamic outer surface. The leading-edge device includes a first coupling element protruding from the inner surface of the first skin element and a second coupling element protruding from the inner surface of the second skin element. The first and second coupling elements are coupled to each other in a coupling region. The first skin element and the first coupling element are formed as a single-piece structure.

Abstract: An energy converter includes a regenerative rectifier electrically connected to a DC voltage circuit and electrically connectable to a first AC voltage grid. The regenerative rectifier includes a first bridge arm with first and second power semiconductor modules connected in series and forming a first center-point pick-up connectable to a first AC voltage phase of the first AC voltage grid. The first power semiconductor module is electrically connected to a first DC voltage phase and the second power semiconductor module is electrically connected to a second DC voltage phase of the DC voltage circuit. First and second capacitors are connected in series and form a second center-point pick-up, with the first capacitor electrically connected to the first DC voltage phase and the second capacitor to the second DC voltage phase of the DC voltage circuit. A coil is electrically connected between the first center-point pick-up and the second center-point pick-up.

Abstract: A filter apparatus for use in a converter in an alternating voltage supply system includes a choke unit, a capacitor unit and saturation reducing unit for the choke unit. A converter having the filter apparatus and to a method for operating the filter apparatus are also disclosed.

Abstract: A leading-edge device for an aerodynamic component is disclosed having a first skin element having an inner surface and an aerodynamic outer surface, and further includes a second skin element having an inner surface and an aerodynamic outer surface. The leading-edge device includes a first coupling element protruding from the inner surface of the first skin element and a second coupling element protruding from the inner surface of the second skin element. The first and second coupling elements are coupled to each other in a coupling region. The first skin element and the first coupling element are formed as a single-piece structure.

Abstract: An arrangement having an insulation monitor for an IT system and a discharge resistor for discharging a ground discharge capacitance of the IT system is provided. The arrangement has two Z diodes that are arranged back-to-back and connected in series with the discharge resistor. Each of the two Z diodes has a reverse voltage above a test voltage of the insulation monitor.

Abstract: A protection apparatus for operating an electric machine at a converter comprises a first and second conductor of a DC link, a switching device having a first and second switch, a link capacitor, a load resistor as a precharge and braking resistor, a semiconductor switch and an electrical fuse for protecting the load resistor. The electrical fuse and the first switch are connected in series to the first conductor and to a first resistor connection of the load resistor and to a first power connection of the semiconductor switch. The second switch is connected to the electrical conductor and to a first capacitor connection of the link capacitor and to a second resistor connection of the load resistor. The semiconductor switch is connected by a second power connection to the second conductor and the link capacitor is connected by a second capacitor connection to the second conductor.

Abstract: An optical observation instrument according to the invention, in particular a surgical microscope or exoscope, comprises an optics unit with an objective arrangement and at least one electronic image recorder, wherein the optics unit has a first stereo channel with a first beam path and a second stereo channel with a second beam path for recording a stereo image of an object field with the at least one electronic image recorder and wherein the first and the second beam path extend through the objective arrangement. Further, the observation instrument comprises a retaining apparatus which comprises a retaining bracket, which engages over the optics unit, wherein the retaining bracket comprises an operating device with a number of operating elements for controlling a retaining arm, to which the retaining apparatus is connectable.

Abstract: A filter apparatus for use in a converter in an alternating voltage supply system includes a choke unit, a capacitor unit and saturation reducing unit for the choke unit. A converter having the filter apparatus and to a method for operating the filter apparatus are also disclosed.

Abstract: A method is proposed for generating a series of ultra-thin sections of a microscopic sample (10), wherein the sections (11) are detached from the sample (10) using an ultramicrotome (100) and wherein the sections (11), which are detached from the sample (10) are caused to float on a liquid surface and are thereafter transferred onto a solid carrier element (20). For at least for some of the sections (11) detached from the sample (10) a position and an orientation on the solid carrier element (20) are determined by monitoring the placement of these sections (11) onto the solid carrier element (20) using a monitoring system (400) comprising a camera (410), obtaining monitoring data. A method (2000) for the three-dimensional reconstruction of a microscopic sample (10), a microtome system and a computer program are also part of the present invention.

Abstract: An energy converter includes a regenerative rectifier electrically connected to a DC voltage circuit and electrically connectable to a first AC voltage grid. The regenerative rectifier includes a first bridge arm with first and second power semiconductor modules connected in series and forming a first center-point pick-up connectable to a first AC voltage phase of the first AC voltage grid. The first power semiconductor module is electrically connected to a first DC voltage phase and the second power semiconductor module is electrically connected to a second DC voltage phase of the DC voltage circuit. First and second capacitors are connected in series and form a second center-point pick-up, with the first capacitor electrically connected to the first DC voltage phase and the second capacitor to the second DC voltage phase of the DC voltage circuit. A coil is electrically connected between the first center-point pick-up and the second center-point pick-up.

Abstract: A protection device, for operating an electric machine at a converter, comprises a first and second conductor of a DC link, a switching device having a first and second switch, a link capacitor, a load resistor as a precharge and braking resistor, a semiconductor switch and an electrical fuse for protecting the load resistor. The electrical fuse and the first switch are connected in series to the first conductor and to a first resistor connection of the load resistor and to a first power connection of the semiconductor switch. The second switch is connected to the electrical conductor and to a first capacitor connection of the link capacitor and to a second resistor connection of the load resistor. The semiconductor switch is connected by a second power connection to the second conductor and the link capacitor is connected by a second capacitor connection to the second conductor.

Abstract: Several DC link converters are interconnected at first and second terminals. Each DC link converter has an input-side rectifier connected to a power supply and an output-side inverter connected to a load, and a DC link with a DC link capacitor. Potentials of the DC link capacitor are connected via first and second lines respective first and second terminals. A switching element and a parallel-connected diode are arranged in at least one of the lines. A control device controls the switching element depending on the DC link voltage and/or as the current flowing through the respective line, allowing the DC link capacitor to be charged, but not discharged via the diode when the switching element is non-conducting, and to be at least discharged when the switching element is conducting. An inductor is arranged in at least one of the lines, and a flyback diode is connected between the lines.

Abstract: A power converter arrangement includes a first converter and a second converter which include each an intermediate voltage circuit and a load-side converter. The intermediate voltage circuit of the first converter is connected electrically to the intermediate voltage circuit of the second converter by a connecting line. The connecting line is connected to a node point either with three partial connecting lines when the load-side power converters include two half-bridges, or with four partial connecting lines when the load-side power converters includes three half-bridges. Each of the partial connecting lines has at least one semiconductor component for generating a voltage drop.

Abstract: An optical observation instrument according to the invention, in particular a surgical microscope or exoscope, comprises an optics unit with an objective arrangement and at least one electronic image recorder, wherein the optics unit has a first stereo channel with a first beam path and a second stereo channel with a second beam path for recording a stereo image of an object field with the at least one electronic image recorder and wherein the first and the second beam path extend through the objective arrangement. Further, the observation instrument comprises a retaining apparatus which comprises a retaining bracket, which engages over the optics unit, wherein the retaining bracket comprises an operating device with a number of operating elements for controlling a retaining arm, to which the retaining apparatus is connectable.

Abstract: A power converter arrangement includes a first converter and a second converter which include each an intermediate voltage circuit and a load-side converter. The intermediate voltage circuit of the first converter is connected electrically to the intermediate voltage circuit of the second converter by a connecting line. The connecting line is connected to a node point either with three partial connecting lines when the load-side power converters include two half-bridges, or with four partial connecting lines when the load-side power converters includes three half-bridges. Each of the partial connecting lines has at least one semiconductor component for generating a voltage drop.

Abstract: Several DC link converters are interconnected at first and second terminals. Each DC link converter has an input-side rectifier connected to a power supply and an output-side inverter connected to a load, and a DC link with a DC link capacitor. Potentials of the DC link capacitor are connected via first and second lines respective first and second terminals. A switching element and a parallel-connected diode are arranged in at least one of the lines. A control device controls the switching element depending on the DC link voltage and/or as the current flowing through the respective line, allowing the DC link capacitor to be charged, but not discharged via the diode when the switching element is non-conducting, and to be at least discharged when the switching element is conducting. An inductor is arranged in at least one of the lines, and a flyback diode is connected between the lines.

Abstract: The invention relates to a freezing machine (150) for freezing samples, encompassing: a freezing device (140) for freezing a sample received in the freezing machine (150); a container (100) for receiving the frozen sample, having a reservoir (105) for liquid nitrogen; and a transfer apparatus for transferring the frozen sample from the freezing device (140) into the container (100), the container (100) comprising at least two receiving devices (104), separated from one another, each for at least one frozen sample; a selection apparatus being provided for selecting one of the receiving devices (104) for a frozen sample that is to be transferred into the container (100), the freezing machine (150) being configured to carry out the transfer of the frozen sample, by means of the transfer apparatus, into the respectively selected receiving device (104) of the container (100); and to a method for transferring frozen samples into a container provided therefor.

Abstract: A discharge device for discharging electrical energy from a circuit of an electrical converter includes an excitation device electrically connected to the circuit and producing during operation of the discharge device from the electrical energy of the circuit an alternating electromagnetic field, and an electrically conductive body constructed as a heatsink and receiving from the excitation device the alternating electromagnetic field so as to induce an eddy current in the electrically conductive body and converting the electrical energy generated in the electrically conductive body into thermal energy. Further disclosed is an electrical converter which includes the afore-described discharge device.