Siemens Ag Osterreich

Other

Andreas Kranister

Harald Schweigert

Harald Weinmeier

Thomas Rothmayer

Switching converter to convert an input direct current (U) into at least one output direct current (U), wherein an internal auxiliary voltage (U, U) is derived from at least one auxiliary winding (W, W) of a transformer (Tr), a controllable load element (BAL) is provided for the output voltage, and a stop signal (s) can be fed to turn the output voltage of the switching converter ON/OFF, which is used to connect the load element (BAL) to the output direct current to such an extent that a short-circuit-like condition is produced, in which the output voltage (U) is adequately close to null, but the at least one auxiliary voltage (U, U) is adequately high to supply the units associated therewith.

Switching converter having a controllable load element

The invention pertains to a method for detecting and/or limiting short-circuit or overcurrent states of a switching regulator, where the load current or a variable proportional to the load current is measured and compared with a predetermined maximum value, and where the result of this comparison is used to influence the switching pulses. In this case, the result of the comparison between the load current and the maximum value is only taken into consideration within at least one time window during at least one timing period of the switching pulses.

Method for recognition and/or limiting the short-circuit state of a switching converter and switching converter

The invention relates to a buffer circuit for a load (LAS) to be supplied by the supply DC voltage (U ), comprising a buffer capacitor (Cp), which may be charged to a voltage (U ) by means of a charging circuit (HSS). Said voltage is higher than the supply voltage and may be brought in for supply of the load by means of a step-down controller (TSS). An input of a step-down controller (TSS) is connected to the buffer capacitor (C ) and the output thereof to the load (LAS), whereby a trigger circuit (TRI) is provided to activate the step-down controller on drop-out of the voltage (U ) at the load.

Buffer circuit

A mains power supply unit for the purpose of supplying consumers that are connected directly or by way of a voltage system converter to a direct voltage branch of a mains power supply unit comprises a buffer capacitor (C) that can be charged from the mains supply and that still supplies the direct voltage branch for a predetermined minimum period of time in the event of a failure or interruption in the mains supply. In such an event, the buffer capacitor (C) can be charged by way of a dedicated charging circuit (,) to a voltage (U,), which, regardless of the voltage fluctuations in the direct voltage branch, is substantially constant and corresponds in a substantial manner to the upper limit value of the direct voltage (U,) to which limit value the mains power supply unit is dimensioned. The buffer capacitor can be connected onto the direct voltage branch by way of a controlled switch (S) in the event of undervoltage in the mains supply or in the direct voltage branch.

Power mains supply unit for directly and/or indirectly supplying consumers with power

A mains power supply for supplying an electricity consumer connected directly or via a converter to an unstabilised direct current branch of the mains power supply, having a buffer capacitor which can be charged from the direct current branch and which also supplies the direct current branch for a predetermined minimum period of time in the event of a mains power failure or interruption in power, and wherein the buffer capacitor (C) is connected via a high impedance charge resistance (R) at the voltage (U1) of the direct current branch, a voltage limiting means (D.sub.z) is connected in parallel with the buffer capacitor (C) and limits the voltage at the capacitor substantially to the minimum voltage (U.sub.M) of the direct current branch which is to be expected in the normal operation, wherein one diode (D) is connected in parallel with the charge resistance and serves to supply the electricity consumer from the buffer capacitor in the event that the input direct current voltage falls below the minimum voltage (U.sub.M).

Growing community of inventors

Wilhelmsburg, Austria

Andreas Kranister