Siemens Aktiengesellschaft

Siemens Energy Global Gmbh & Co. Kg

Jürgen Rupp

Reinhard Maier

Werner Hartmann

Gerd Griepentrog

Martin Hergt

Birger Schmidt

Arno Döbbeler

Martin Bischoff

Ralf Cordes

Michael Schröck

Various embodiments include a device for coupling two DC grids comprising source-side and load-side capacitances comprising: a switching device for current regulation, the switching device including two series-connected switching modules; wherein each of the switching modules includes at least one controllable semiconductor switching element connected in parallel to a respective series circuit comprising a resistor and a capacitor; and a control unit. The control unit is programmed to: switch the controllable semiconductor switching element of one of the two switching modules on and at the same time switch the controllable semiconductor switching element of the other of the two switching modules off; switch the controllable semiconductor switching element of the other of the two switching modules on and at the same time switch the controllable semiconductor switching element of the one of the two switching modules off; repeat steps a) and b) until the voltages of the source-side and load-side capacitances have aligned with one another; and switch the controllable semiconductor switching elements of the two switching modules on.

Device and method for coupling two DC grids

Various embodiments include an apparatus for limiting voltage for a DC voltage network, wherein overvoltages resulting from switching operations occur between a first supply potential level and a second supply potential level of the DC voltage network. The apparatus comprises at least two limiter cells connected in series between the first supply potential level and the second supply potential level. Each limiter cell comprises a controllable switching element, a discharge resistor, and a capacitor, across all of which a voltage applied between the first supply potential level and the second supply potential level is dropped. During operation of the apparatus, based at least in part on the voltage dropped across the respective capacitor of a particular limiter cell, the controllable switching element of the limiter cell is switched on or off.

Apparatus for limiting voltage for a DC voltage network

Various embodiments include a switching device for disconnecting a current path in a DC supply system, said current path comprising inductances at the source end and the load end, the switching device comprising: two series-connected switching modules; wherein each of the series-connected switching modules comprises a controllable semiconductor switching element and a series circuit; the series circuit including a resistor and a capacitor connected in parallel to the controllable semiconductor switching element.

Switching device for disconnecting a current path

Various embodiments may include a voltage switch having two terminals linked by an operating current path comprising a mechanical switch, and having means of generating a counter voltage to the voltage in the operating path. In some embodiments, there are: two terminals linked by an operating current path comprising a mechanical switch; a transformer having a primary side connected in series with the mechanical switch in the operating current path; a voltage source connected to a secondary side of the transformer; and a switch connected in series with the voltage source.

DC voltage switch

Power is supplied to excitation windings in order to generate magnetic fields, preferably for activating superconducting coils. An AC transformer is used, and triggering of the coil is performed via a rectifier having little power loss. Preferably, a two-way rectifier using a freewheeling circuit is utilized in the associate device, thus preventing losses when power is supplied and especially when the power is discharged.

Method for supplying and discharging power to and from a resistive-inductive load, and rectifier used therein

An anti-serial cascade circuit including two silicon carbide JFETs and two silicon MOSFETs is known. Disclosed is a combination of a JFET, a smart power MOSFET SPM and a thyristor with an associated trigger circuit, which is connected in parallel to the SPM. According to an embodiment of the invention, a logic circuit co-ordinates the functional sequence.

Electronic switching device, in particular circuit-breaker and associated operating method

Individual measuring sensors each have a different specific signal type and must therefore be appropriately connected to the analog measuring inputs. An adjustable voltage with adjustable current limitation, or an adjustable current with adjustable voltage clamping is used. The voltage or current is connected to the measuring sensors and the corresponding signal is detected and classified according to the sensor type. This permits the automated integration of the measuring sensor. The corresponding assembly can form part of the complete module.

Method for identifying analog measuring sensors and associated assembly

A method with corresponding circuit arrangement is disclosed, whereby for evaluation of a measured signal arising as an analogue value with a potential greater than zero potential in a measuring device requiring a supply current, the measured information therefrom is transmitted as a digital signal to an analytical unit lying at earth potential after an A/D conversion. The generated digital signal thus provides the clock signal for a modulation of the supply current and thus also carries out the function of the carrier for the information content of the measured signal. Curved characteristic lines for compression/decompression of the signals are used. Suitable devices for temperature compensation may be similarly provided.

Method and circuit arrangement for current measurement

In order to measure the current in a shunt, the voltage drop in the resistor of said shunt is evaluated as a measurement of the current. Normally, galvanic separation of the measuring device is required for high-potential shunts. A digital measuring signal provides the clock pulse for modulation of the supply current for the measuring device after an A/D conversion. The modulated supply current is also used as a carrier for the measuring information. In the associated evaluation device, an A/D converter and a modulation unit are arranged downstream from an amplifier for voltage signal which is picked off from the shunt. The modulated measuring signal is transmitted to an evaluation device.

Method for evaluating a measuring signal and corresponding circuit arrangement

By rectifying, comparing and X-OR gating two signals (A,B) from a transmitting device (G) that are to be sinusoidal and have a corresponding rotational frequency, of the same amplitude, and ideally offset from one another electrically by 90.degree., a binary signal (RD) is generated that is indicative of whether a disturbance of the two signals (A,B) exists. A processing device (VE) determines if errors exist with respect to the amplitude, the offset or the phase relationship of the signals (A,B) by monitoring the mark-to-space ratio of the binary signal (RD) for its adherence to a ratio of 1:1, and generates a signal indicative of a disturbance when an error is determined to exist. Additionally, by dividing the binary signal (RD) via a 1:8 convertor (U) and monitoring that signal, the processing device can determine if a change in the rotational frequency of the two signals (A,B) of the transmitting device occurs.

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Erlangen, Germany

Jürgen Rupp