Abstract: Described is an electric circuit which is intended, in particular, for the testing of a power producer in a wind power plant. The power producer is connected to a terminal point and is provided with a converter circuit which can be used to influence a voltage that is present at the terminal point. Also provided is a series connection configured with a choke coil and a first switch and connected to the terminal point. In at least one embodiment, a control and/or regulating system is provided for influencing, in a time-synchronized manner, on the one hand the converter circuit, such that the voltage at the terminal point transitions to a desired value and, on the other hand, the closing of the first switch.

Abstract: One embodiment of the present invention discloses a method for operating a mill train, in particular used in a cold-rolling mill. The mill train includes operating rolls with a roll gap disposed in-between through which a rolled strip is guided. With the method of at least one embodiment, the thickness and the roll-in speed of the rolled strip are measured in front of the roll gap. The roll-out speed of the rolled strip after the roll gap is reconstructed with the aid of the tangential speed of the operating rolls. The thickness after the roll gap is then determined with the aid of the thickness and the roll-in speed in front of the roll gap and the reconstructed roll-out speed.

Abstract: Described is a method for operating a converter for a system for generating electrical energy. In an embodiment of the method, the output voltage of the converter is converted to a d, q coordinate system, wherein the d, q coordinate system is assigned to the frequency of the voltage for the energy supply grid. A desired value is furthermore specified in the d, q coordinate system, several momentary or future values are determined from the output voltage in the d, q coordinate system for different switch positions of the converter, deviations between the desired value and the momentary or future values are determined in the d, q coordinate system, and the converter is switched to one of the switch positions in dependence on these deviations.

Abstract: Described is a circuit for converting electric power between a three-phase grid and a single-phase grid. The circuit includes, in at least one embodiment, a first transformer that is connected to the three-phase grid, a number of first converter stages assigned to the first transformer, the associated DC intermediate circuits and the associated second converter stages. The second converter stages are connected to each other at the alternating-current side outputs with the aid of a series connection.

Abstract: Described is a modular switch for an electrical converter. The modular switch is provided with a first series circuit including a first controllable power semiconductor component and a first diode as well as with a second series circuit including a second diode and a second controllable power semiconductor. The connecting point between the first power semiconductor component and the first diode forms a first terminal and the connecting point between the second diode and the second power semiconductor component forms a second terminal of the modular switch. Also provided is a capacitor, wherein the first series circuit and the second series circuit and the capacitor are switched parallel to each other.

Abstract: Described is a heat sink for an electronic component. In at least one embodiment, the heat sink includes several cooling fins and carbon nanotubes, present between the top surface of the heat sink and the cooling fins. The carbon nanotubes extend from the top surface of the heat sink in the direction toward one of the cooling fins and are oriented at an angle to the orientation of the associated cooling fin.

Abstract: Described is a transport vehicle provided with a plurality of electrical machines and power converters which serve to connect the electrical machines to a DC intermediate circuit. Also provided is a separate power converter for feeding electrical energy into the DC intermediate circuit. All power converters are respectively configured with an identical power electronic module which includes controllable power semiconductor switches, wherein different functions can be achieved through differently activating the power semiconductor switches.

Abstract: Described is a cooling device for cooling an equipment component with the aid of a cooling agent, as well as a method for cooling an equipment component. In at least one embodiment, the cooling device includes a heat source for transferring thermal energy from the equipment component to the cooling agent and a heat sink for dissipating thermal energy from the cooling agent. The heat source and the heat sink are connected to each other. The cooling agent can be supplied via a forward flow line to the heat source and can flow via a return line away from the heat sink. The cooling device includes a control mechanism and two storage containers or a stratified storage tank for the cooling agent. The control mechanism is connected to the two containers and/or the stratified storage tank, the forward flow line and the return flow line.

Abstract: Disclosed is an electric circuit, in particular for a medium voltage power converter. The circuit has at least four semiconductor switches which form a series connection and which are connected to poles of a direct current voltage (Ud). A diode is connected in parallel in an inverse direction to each semiconductor switch. A capacitor is connected in parallel to the two semiconductors in the middle of the series connection. The circuit is provided with a pole of an output potential (Ua) which is connected centrally in the series connection. The circuit has a control device for successively controlling the semiconductor switches. The time interval between the transition of two of the semiconductor switches into their respective controlling states is minimal.

Abstract: A wind turbine includes a turbine rotor with at least one blade and a generator with a rotor and a stator. The turbine rotor is mechanically coupled with the rotor of the generator. A diode rectifier is electrically coupled to the stator of the generator. A direct current link is electrically coupled with the diode rectifier. A line converter is electrically coupled with the direct current link.