摘要:
The disclosure relates to a converter control unit or power system stabilizing unit for counteracting oscillations in electric power systems that is equipped and employed to provide and processes information for system-wide monitoring, protection, control and metering. It comprises means for synchronized (e.g. via GPS or another absolute/global time reference) sampling of voltages and/or currents, means for down-sampling in order to decrease the number of samples, and means for calculating phasors, i.e. time stamped amplitude and phase angle of the voltages and/or currents.
摘要:
The disclosure relates to a converter control unit or power system stabilizing unit for counteracting oscillations in electric power systems that is equipped and employed to provide and processes information for system-wide monitoring, protection, control and metering. It comprises means for synchronized (e.g. via GPS or another absolute/global time reference) sampling of voltages and/or currents, means for down-sampling in order to decrease the number of samples, and means for calculating phasors, i.e. time stamped amplitude and phase angle of the voltages and/or currents.
摘要:
The document specifies a method for fault handling in a converter circuit for switching three voltage levels, in which the converter circuit has a converter subsystem provided for each phase (R,S,T), in which a top fault current path (A) or a bottom fault current path (B) in the converter subsystem is detected, the top fault current path (A) running through the first, second, third and sixth power semiconductor switches in the converter subsystem or through the first and fifth power semiconductor switches (S1, S5) in the converter subsystem, and the bottom fault current path (B) running through the second, third, fourth and fifth power semiconductor switches in the converter subsystem or through the fourth and sixth power semiconductor switches in the converter subsystem, and in which the power semiconductor switches are switched on the basis of a fault switching sequence. To avoid phase shorting of all the phases of the converter circuit in order to achieve a safe operating state for the converter circuit in the event of a fault, the fault switching sequence in the event of detection of the top or the bottom fault current path (A, B) is initially followed by the detection's accompanying switching status of each power semiconductor switch being recorded. In addition, in the event of detection of the top fault current path (A) the first power semiconductor switch and then the third power semiconductor are turned off, and in the event of detection of the bottom fault current path (B) the fourth power semiconductor switch and then the second power semiconductor are turned off.
摘要:
This invention relates to an improvement in a hot water pump having a cooled sealing housing in a pump cover in the upper pump portion. The improvement comprises means mounting the sealing housing in a recess of the pump cover in a manner such that an annular air space is present between the outer surface of said sealing housing and the inner surface of the recess of the pump cover, said air space being in communication with the exterior space surrounding the pump.
摘要:
A starting apparatus is disclosed for at least two synchronous machines, which starting apparatus includes an exciter unit which is provided for each synchronous machine and is associated with the respective synchronous machine. Each exciter unit can be connected to the field winding of the associated synchronous machine. A superordinate control unit is provided, with the superordinate control unit being connected via a communication link to each exciter unit. Furthermore, the starting apparatus includes at least one stator feed unit and at least one switching device, which is provided for each stator feed unit and is associated with the respective stator feed unit, in which case the respective switching device can be connected to the associated stator feed unit, the respective switching device can be connected to at least one synchronous machine, and the switching devices can be connected to one another when there are a plurality of switching devices. The exciter units can be connected to one another via a ring communication link. Each stator feed unit can be connected to the ring communication link. Each stator feed unit can also be connected via a communication link to an associated switching device, and exciter units which are associated with the stator feed units can be each connected via a communication link to a switching device.
摘要:
The document specifies a method for fault handling in a converter circuit for switching three voltage levels, in which the converter circuit has a converter subsystem provided for each phase (R,S,T), in which a top fault current path (A) or a bottom fault current path (B) in the converter subsystem is detected, the top fault current path (A) running through the first, second, third and sixth power semiconductor switches in the converter subsystem or through the first and fifth power semiconductor switches (S1, S5) in the converter subsystem, and the bottom fault current path (B) running through the second, third, fourth and fifth power semiconductor switches in the converter subsystem or through the fourth and sixth power semiconductor switches in the converter subsystem, and in which the power semiconductor switches are switched on the basis of a fault switching sequence. To avoid phase shorting of all the phases of the converter circuit in order to achieve a safe operating state for the converter circuit in the event of a fault, the fault switching sequence in the event of detection of the top or the bottom fault current path (A, B) is initially followed by the detection's accompanying switching status of each power semiconductor switch being recorded. In addition, in the event of detection of the top fault current path (A) the first power semiconductor switch and then the third power semiconductor are turned off, and in the event of detection of the bottom fault current path (B) the fourth power semiconductor switch and then the second power semiconductor are turned off.