Abstract: An electric power converter for converting AC to DC power or DC to AC power is disclosed. The converter includes a circuit for controlling the voltage and the circuit for controlling the current separately. The voltage is controlled by the switching modules and the up-side controller using the calculated target voltage. The current is controlled by the current controller using the calculated target current.

Abstract: An electric power converter for converting AC to DC power or DC to AC power is disclosed. The converter includes a circuit for controlling the voltage and the circuit for controlling the current separately. The voltage is controlled by the switching modules and the up-side controller using the calculated target voltage. The current is controlled by the current controller using the calculated target current.

Abstract: A converter includes building blocks, each building block being a switching unit. Each building block must be able to receive high power at an elevated switching frequency with low power dissipation in semiconductor switches. The building block includes semiconductor switches and a reactor connected in series, and a series connection of a voltage clamp and a diode. The series connection is connected in parallel to each of the semiconductor switches. The clamps are arranged in such a way that all clamping and voltage control is realised by a clamp connected in parallel with the corresponding semiconductor switch.

Abstract: A converter has a plurality of building blocks, each block is a switching unit. Each building block must be able to receive high power at elevated switching frequency with low power dissipation in the semiconductor switches. The building block includes semiconductors switches and a reacter connected in series, and series connection of a voltage clamp and a diode. The series connection is connected in parallel to each of the semiconductor switches. The clamps are arranged in such a way, that all clamping and voltage control are realised by a clamp connected in parallel to the corresponding semiconductor switch.

Abstract: A signal pattern is generated to produce a current for driving a GCT thyristor. The current is produced by the use of a down converter. Also, a current limiter having an FET is used for protecting the down converter from being damaged by a negative voltage appearing at the gate of GCT when the GCT thyristor receives a reverse direction load current.

Abstract: A semiconductor clamped-stack assembly (32) has at least two clamped stacks, each of these clamped stacks having a plurality of power semiconductor components (8) and a plurality of heat sinks (6), which are arranged in series along a horizontally extending axial direction (A). According to the invention, power semiconductor components (8) from different clamped stacks are assigned to one another and are located in a common mounting plane, which is perpendicular to the axial directions (A) of the clamped stacks (31). Mutually associated power semiconductor components (8) can be removed from the clamped-stack assembly or, respectively, inserted into the clamped-stack assembly in a common mounting direction, which lies in the mounting plane. Mutually associated power semiconductor components (8) are preferably mounted on a common plate (14). As a result, they can be dismantled when the clamped-stack assembly (32) is loosened, without further power semiconductor components or heat sinks having to be dismantled.

Abstract: A predetermined signal pattern is generated to produce current for driving the GCT thyristor. The current is produced by the use of a down converter. Also, a current limiter having an FET is used for protecting the down converter from being damaged by a negative voltage appearing at the gate of GCT when the GCT thyristor receives reverse direction load current.

Abstract: The invention specifies a disconnector for decoupling a load from a supplying AC power supply system. The disconnector comprises a transformer whose primary is connected into the AC power supply system. On the secondary side, a rectifier circuit is provided which has a turn-off thyristor connected to it. In normal operation, the turn-off thyristor is kept closed, so that the power supply system supplies the load. In the event of power supply system faults or interruptions, the turn-off thyristor is opened, which disconnects the power supply system from the load owing to the transformer impedance.

Abstract: A method for turning a GTO on and off and a corresponding driving circuit are specified. A turn-on current and a holding current are generated from voltage pulses which are converted into currents with the aid of an electric energy store. In terms of circuitry, it is particularly advantageous when the required voltage pulses are drawn from the same energy source, or the same energy store, as the pulse required to generate the turn-off current. The holding current is preferably generated by repeating voltage pulses. The repetition frequency of said voltage pulses can then be increased or reduced as required. The frequency is reduced, in particular, when the gate-cathode voltage becomes negative, and is increased again when the voltage is positive again.