Abstract: The present disclosure relates to a power grid including a converting stage including a plurality of DC/DC converters connected in parallel. At least one of the DC/DC converters is a single-stage isolated DC/DC converter including a voltage control configured to control a voltage of the respective DC/DC converter.

Abstract: An electrical interconnection circuit can be used with a solid-state-transformer (SST) system. The interconnection circuit includes medium voltage direct current (MVDC) to low voltage direct current (LVDC) direct current to direct current (DC/DC) converters, independent LVDC buses respectively connected to one of the MVDC to LVDC DC/DC converters, and an interconnecting DC/DC converter connecting at least two of the independent LVDC buses in order to ensure equal power demand from each MVDC to LVDC DC/DC converters. The interconnecting DC/DC converter is configured to re-route power between the plurality of independent LVDC buses. A power rating of the interconnecting DC/DC converter is set according to power to be rerouted from other LVDC buses via the interconnecting DC/DC converter.

Abstract: The disclosure relates to a power grid, comprising a converting stage comprising a plurality of DC/DC converters. At least one of the DC/DC converters is a single-stage isolated DC/DC converter comprising a voltage control configured to control a voltage of the respective DC/DC converter. The DC/DC converters are connected in series and at least one of the plurality of converters of the converting stage is configured to provide a respective predetermined output voltage to a load.

Abstract: An electrical interconnection circuit can be used with a solid-state-transformer (SST) system. The interconnection circuit includes medium voltage direct current (MVDC) to low voltage direct current (LVDC) direct current to direct current (DC/DC) converters, independent LVDC buses respectively connected to one of the MVDC to LVDC DC/DC converters, and an interconnecting DC/DC converter connecting at least two of the independent LVDC buses in order to ensure equal power demand from each MVDC to LVDC DC/DC converters. The interconnecting DC/DC converter is configured to re-route power between the plurality of independent LVDC buses. A power rating of the interconnecting DC/DC converter is set according to power to be rerouted from other LVDC buses via the interconnecting DC/DC converter.

Abstract: Techniques for assessing a health of a transformer breather are provided. The transformer breather contains a desiccant and is in fluid communication with an expansion tank of a fluid-insulated transformer. A weight measurement that is dependent on a weight of the transformer breather or of a component or sub-assembly thereof is processed to assess the health of the transformer breather.

Abstract: A transformer assembly includes an electric transformer, a temperature sensor system, and a computation unit for determining a thermal state of the electric transformer. The electric transformer includes a cooling device having at least one liquid coolant channel to absorb exhaust heat from the electric transformer, a heat spreader for transferring heat from the liquid coolant to a heat dissipation surface of the heat spreader, and an air blower configured to effect an airstream along the heat dissipation surface. The temperature sensor system includes an entering coolant sensor for providing an entering coolant temperature signal, a leaving coolant sensor for providing a leaving coolant temperature signal, an entering airstream sensor providing an entering airstream temperature signal, and a leaving airstream sensor providing a leaving airstream temperature signal. The computation unit is configured to determine a thermal state of the transformer.

Abstract: An aspect of the present disclosure provides a method for measuring a quantity of liquid in a liquid-insulated electrical component. The liquid-insulated electrical component includes a main tank (1) and an expansion tank (2) fluidly connected to the main tank (1). The method includes measuring a first pressure (P1) of the liquid at a first point in the main tank (1), measuring a second pressure (P2) of the liquid at a second point in the main tank (1), the second point being at a height (H) above the first point, measuring a third pressure (P3) of the liquid at a third point in the expansion tank (2), and determining the quantity of liquid in the liquid-insulated electrical component based, on the first pressure (P1), the second pressure (P2) and the third pressure (P3).

Abstract: A transformer assembly includes an electric transformer a temperature sensor system, and a computation unit for determining a thermal state of the electric transformer. The electric transformer includes a cooling device having at least one liquid coolant channel to absorb exhaust heat from the electric transformer a heat spreader for transferring heat from the liquid coolant to a heat dissipation surface of the heat spreader, and an air blower configured to effect an airstream along the heat dissipation surface. The temperature sensor system includes an entering coolant sensor for providing an entering coolant temperature signal, a leaving coolant sensor for providing a leaving coolant temperature signal, an entering airstream sensor for providing an entering airstream temperature signal, and a leaving airstream sensor for providing a leaving airstream temperature signal. The computation unit is configured to determine a thermal state of the transformer.

Abstract: A transformer assembly includes an electric transformer a temperature sensor system, and a computation unit for determining a thermal state of the electric transformer. The electric transformer includes a cooling device having at least one liquid coolant channel absorb exhaust heat from the electric transformer a heat spreader for transferring heat from the liquid coolant to a heat dissipation surface of the heat spreader, and an air blower configured to effect an airstream along the heat dissipation surface. The temperature sensor system includes an entering coolant sensor for providing an entering coolant temperature signal, a leaving coolant sensor for providing a leaving coolant temperature signal, an entering airstream sensor for providing an entering airstream temperature signal, and a leaving airstream sensor for providing a leaving airstream temperature signal. The computation unit is configured to determine a thermal state of the transformer.

Abstract: The invention relates to a traction transformer for railbound vehicles comprising: an insulating liquid filled enclosure, at least two windings contained in the enclosure, a transformer core, mounting means for mounting the transformer to the railbound vehicle, wherein the transformer core is arranged outside the enclosure, and wherein the mounting means are attached to the transformer core.

Abstract: A transformer which includes an enclosure with a first and second cover arranged at opposite ends of the enclosure, the enclosure having an enclosed volume filled with isolation material and including at least one channel which extends through the enclosure from the first cover to the second cover. The interior of each channel is separated from the enclosed volume, and the core is provided outside of the enclosed volume and comprises a leg and a yoke. The leg extends through the channel. The transformer further includes a coil inside the enclosed volume and being wound about the channel. The first and second cover each comprise an electrically insulating material and at least one electrically conductive component.

Abstract: A transformer is provided, which comprises an enclosure (10) with a first and second cover (12, 14) arranged at opposite ends of the enclosure (10), the enclosure having an enclosed volume (11) filled with isolation material (20) and comprising at least one channel (25, 26) which extends through the enclosure (10) from the first cover (12) to the second cover (14). The interior of each channel (25, 26) is separated from the enclosed volume (11), and the core (30) is provided outside of the enclosed volume (11) and comprises a leg (32, 34) and a yoke (40, 42). The leg (32, 34) extends through the channel (25, 26). The transformer (5) further comprises a coil (50, 52) inside the enclosed volume (11) and being wound about the channel (25, 26). The first and second cover (12, 14) each comprise an electrically insulating material (58) and at least one electrically conductive component (60).

Abstract: The invention relates to a traction transformer for railbound vehicles comprising: an insulating liquid filled enclosure, at least two windings contained in the enclosure, a transformer core, mounting means for mounting the transformer to the railbound vehicle, wherein the transformer core is arranged outside the enclosure, and wherein the mounting means are attached to the transformer core.

Abstract: An arrangement for reading out an analog voltage input signal includes an input applying the input signal thereto, and a reference unit generating an analog reference voltage. To perform online self-calibration, the arrangement includes a superposition unit generating a combined analog signal by superimposing the analog reference voltage onto the input signal, a converting unit converting the combined analog signal into a one-bit serial data stream at a conversion sampling rate, and a decomposition unit, which includes at least two digital filters configured to generate from the serial data stream two corresponding digital signals at different data rates, which can be less than the conversion sampling rate.

Abstract: An arrangement for reading out an analog voltage input signal includes an input applying the input signal thereto, and a reference unit generating an analog reference voltage. To perform online self-calibration, the arrangement includes a superposition unit generating a combined analog signal by superimposing the analog reference voltage onto the input signal, a converting unit converting the combined analog signal into a one-bit serial data stream at a conversion sampling rate, and a decomposition unit, which includes at least two digital filters configured to generate from the serial data stream two corresponding digital signals at different data rates, which can be less than the conversion sampling rate.