Abstract: A converter station has two line-commutated converters for energy transmission via a bipolar high voltage direct current transmission line. In a first operating mode of the converter station the two converters are electrically connected in an anti-parallel circuit to the same pole of the high voltage direct current transmission link and one of the converters is operated as a rectifier and the other converter is operated as an inverter in an network. In a second operating mode the two converters are connected to different poles of the high voltage direct current transmission link and both converters are operated as either rectifiers or inverters in the AC network. In both operating modes a station active power exchanged between the converter station and the AC network is controlled by active power specifications for converter active powers which are exchanged between the converters and the AC network.

Abstract: A converter station includes two line-commutated converters for energy transmission through a bipolar high voltage direct current transmission link. The two converters are electrically connected in an anti-parallel circuit to the same pole of the high-voltage direct current transmission link. One of the converters is operated as a rectifier in an AC grid and the other converter is operated as an inverter in the AC grid. A station reactive power exchanged by the converter station with the AC grid is controlled by real power stipulations for converter real powers which are exchanged between the converters and the AC grid. A method for operating the converter station is also provided.

Abstract: A converter station has two line-commutated converters for energy transmission via a bipolar high voltage direct current transmission line. In a first operating mode of the converter station the two converters are electrically connected in an anti-parallel circuit to the same pole of the high voltage direct current transmission link and one of the converters is operated as a rectifier and the other converter is operated as an inverter in an network. In a second operating mode the two converters are connected to different poles of the high voltage direct current transmission link and both converters are operated as either rectifiers or inverters in the AC network. In both operating modes a station active power exchanged between the converter station and the AC network is controlled by active power specifications for converter active powers which are exchanged between the converters and the AC network.

Abstract: A converter station includes two line-commutated converters for energy transmission through a bipolar high voltage direct current transmission link. The two converters are electrically connected in an anti-parallel circuit to the same pole of the high-voltage direct current transmission link. One of the converters is operated as a rectifier in an AC grid and the other converter is operated as an inverter in the AC grid. A station reactive power exchanged by the converter station with the AC grid is controlled by real power stipulations for converter real powers which are exchanged between the converters and the AC grid. A method for operating the converter station is also provided.

Abstract: An apparatus for detecting and processing a multiplicity of measured values in an HVDCT system has measuring units for detecting measured variables of the HVDCT system, while obtaining measured values, and preprocessing units which are connected to one another in series, are each connected to at least one measuring unit and are connected to a control, regulation and monitoring system by means of a last preprocessing unit which is connected downstream of the rest of the preprocessing units, each preprocessing unit being set up to receive and preprocess the measured values, while obtaining optical measured values, and transmitting both the optical measured values generated by it and the optical measured values received from the upstream preprocessing units to a downstream preprocessing unit or to the control, regulation and monitoring system, with the result that the last preprocessing unit provides all of the measured values for the control, regulation and monitoring system.

Abstract: An evertable drum centrifuge has a drum with a generally cylindrical and perforate outer wall and having an axially forwardly open front end. An end wall of the drum can move axially between a closed position fitting in the front outer-wall end and an open position spaced axially forward of the outer wall and is centrally formed with a fill opening. An annular liner of a flexible foraminous filter medium has a front edge attached to the outer-wall end and a back edge attached to a rim of extension structure fixed on the end wall. When the end wall move between the closed and open positions, the liner moves from a normal position inside the drum and extending backward from the front end to the rim to an everted position substantially outside the drum and extending forward in the solids compartment from the front end to the rim. An axially displaceable fill tube carries an axially nondisplaceable fill head complementarily engageable in the fill opening and having an annular seal engageable with the fill tube.

Abstract: A centrifuge has an upper wall formed with an inspection port, a cover engageable over the port, and an annular seal on the cover compressible against the port in a closed position of the cover. A hinge and operating assembly has a hydraulic cylinder/piston unit having one end pivoted on the housing, at least one pivot lug on the cover defining a cover axis, at least one pivot lug on the housing defining a housing axis parallel to the cover axis, and a support link having one end pivoted on the housing pivot lug at the housing axis and an opposite end defining a support axis. An operating lever centrally pivoted on the opposite end of the support link at the support axis has an end portion extending from the support axis and connected to the opposite end of the hydraulic unit and an opposite end portion on pivoted to one end of an operating link having an opposite end pivoted on the cover lug at the cover axis.

Abstract: A state signal is formed to indicate a transition to a bypass mode of operation. In forming the signal of each winding system of a corresponding converter transformer on a side of the converter transformer are determined, weighted with weighting factors and summed up. The summation current formed in this manner does not have any null zones in the normal operation of the converter. All weighting factors are different if the phase currents between the converter and the converter transformer are used to produce the summation current. In the case of a converter transformer which is connected to the converter via a delta-connected winding system and in which the winding currents are used, certain differences formed by the weighting factors are not to be the same. A DC Hall converter with an insertion hole is particularly well suited for weighting and combining the currents of each individual winding system.