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: 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: 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 receiving unit is more precisely synchronized to a transmitting unit by transmitting synchronization signals from the transmitting unit, adjusting a clock-pulse generator of a phase-locked loop, a phase shifter integrating instantaneous phase errors to an integration value, and adjusting the integration value to an integration fraction that is less than one.