Hitachi Energy

The present disclosure relates to a retrieval-augmented generation (RAG) system. The system comprises a controller node configured to receive a query, a plurality of retriever nodes provided in parallel to each other and communicatively coupled to the controller node, an evaluation node communicatively coupled to the plurality of retriever nodes, and a language model (LM) node communicatively coupled to the evaluation node and the plurality of retriever nodes. The controller node is configured to forward the query to the plurality of retriever nodes, the plurality of retriever nodes are configured to simultaneously generate, based on the query, respective intermediate responses, the evaluation node is configured to receive the respective intermediate responses and assign a score to each of the intermediate responses, and the LM node is configured to generate a final response based on the intermediate responses and the assigned score.

In at least one embodiment, the static electric induction device (1) comprises: - a tank (2) configured to be filled with an electrically insulating liquid (3), and - a gas analyzer (5) configured to provide concentration data indicative of an oxygen concentration of a gas sample (40), wherein - the gas analyzer (5) comprises a laser (51) configured to emit a test radiation (52) which is narrow-band radiation, and - the concentration data is optical absorption data of the test radiation (52) through the gas sample (40).

The present disclosure relates to a computer-implemented method comprising: estimating a plurality of dynamic phasors x̂_in,k(θ) of a single- or multi-phase input signal x_in(θ), corresponding to an electrical parameter of an electrical power system (EPS), wherein said step of estimating said plurality of dynamic phasors x̂_in,k(θ) comprises: based on information at least indicative of a highest harmonic order of non-negligible dynamic phasors of the input signal x_in(θ), selecting a finite harmonic order k_max equal to or greater than said highest harmonic order of non-negligible dynamic phasors of the input signal x_in(θ), providing a set of matrix representations (x̂, K, d, ŷ, G, I, Γ) based on said input signal x_in(θ) and/or said finite harmonic order k_max, and computing a plurality of matrix operations applied to said set of matrix representations (x̂, K, d, ŷ, G, I, Γ) to provide a corresponding plurality of dynamic phasor estimates x̂_k(θ) (k ∈ {-k_max, ..., k_max}) to said plurality of dynamic phasors x̂_in,k(θ), wherein the plurality of matrix operations represents at least a first step of extracting signals ŷ_k(θ) (k ∈ {-k_max, ..., k_max}) from the input signal x_in(θ) by application of a plurality of lowpass filters, and a second step of applying harmonic cancellation on the signal components y_k(θ) = e^jkθŷ_k(θ), wherein said phase angle θ is controlled via a phase locked loop, PLL, which PLL receives as input at least one component of the plurality of dynamic phasor estimates x̂_k(θ).The present disclosure further relates to a phasor measurement unit, PMU, a monitoring system, a control device, and a power supporting system.

The invention relates a protection circuit (100) for protecting modular multilevel converter, MMC, cell, a MMC cell (1000) and a protection method. The protection circuit (100) comprises a bypass semiconductor device (1) with a first thyristor structure (10) and a second thyristor structure (20) connected in antiparallel. The first thyristor structure (10) comprises a first trigger region (61) and a first emitter region (71). The second thyristor structure (20) comprises a second trigger region (62) and a second emitter region (72). The disposition of the trigger regions (61, 62) and of the emitter regions (71, 72) being such that in response to a failure of the MMC cell, the first thyristor structure (10) fails to a permanent short circuit by a first gate pulse current between the first trigger region (61) and the first emitter region (71), while the second thyristor structure (20) fails to a permanent short circuit by a second gate pulse current between the second trigger region (62) and the second emitter region (72).

A power module (1) comprising several switching units (2a, 2b, 2c) and a cooler (3) for liquid cooling, wherein the switching units (2a, 2b, 2c) are mounted on the cooler (3), wherein the cooler (3) comprises an inlet (6) and an outlet (8) for a cooling liquid, the inlet (6) and the outlet (8) being located on a top side (4) and/or a bottom side (5) of the cooler (3), wherein in a view on the top side (4) of the cooler (3) an overlap (Aa, Ab, Ac) of one of the switching units (2a, 2b, 2c) with the inlet (6), the outlet (8), a blind channel section (19) of the cooling channel (7) and/or an area of the cooler (3) where the cooling channel (7) is not present is larger than for another one of the switching units (2a, 2b, 2c).

The invention relates to a semiconductor device, a bypass circuit comprising the semiconductor device and a method manufacturing the semiconductor device. The semiconductor device (1) comprising a first thyristor structure (10) and a second thyristor structure (20) which are antiparallel connected and share a common semiconductor body (2). A first main electrode (51) functions as a cathode (11) for the first thyristor structure (10) and an anode (22) for the second thyristor structure (20). A second main electrode (52) functions as an anode (12) for the first thyristor structure and a cathode (21) for the second thyristor structure (20). The semiconductor body further comprises a first trigger region (61) and a first emitter region (71) facing the first gate and main electrodes, a second trigger region (62) and a second emitter region (72) facing the second gate and main electrodes to facilitate self-destruction of the thyristor structures.

The disclosure provides a method for controlling a hybrid transformer, HT, comprising an electric line with a plurality of phases, a first transformer connected to the electric line in series, and a converter module connected on a first side to the electric line in shunt, and a second side of the converter module, opposite to the first side, being connected to the first transformer; wherein the converter module comprises a shunt connected converter with an alternating current, AC, side which is the first side of the converter module, and the converter module further comprises a series connected converter with an AC side of the series connected converter which is the second side of the converter module, wherein a direct current, DC, side of the shunt connected converter is connected to a DC side of the series connected converter by a DC link, the method comprising: obtaining: a first voltage of each of the plurality of phases of the electric line at a first point of common coupling, PCC, where the shunt connected converter is connected to the electric line in shunt, a second voltage of each of the plurality of phases of the electric line at a second PCC, where the first transformer is connected to the electric line, and a first current of each of the plurality of phases of the electric line at the second PCC; determining a voltage imbalance and/or a current imbalance based on the obtained first voltage, second voltage and/or first current; and controlling, based on the determined voltage imbalance and/or current imbalance, the shunt connected converter to inject an injection current and/or the series connected converter to inject an injection voltage for balancing the magnitudes and/or phase angles of a voltage and/or a current between the plurality of phases of the electric line.

The invention relates to an apparatus (1) for connection to a gas-insulated electrical device (100) and providing an interior for insulating gas, e.g. gas-insulated line or gas-insulated switchgear, comprisinga first housing member (10) sectionally forming the interior, having openings (11, 12, 13) of which a first opening (11) includes a first flange (F1); anda second housing member (30) sectionally forming the interior, including a further flange (F3) and connected for telescoping in an axial direction (X1) and in an electrically conductive manner to the first housing member (10) at a further opening (13) of the openings (11, 12, 13).

The disclosure provides a method for controlling a hybrid transformer, HT, comprising an electric line with a plurality of phases, a first transformer connected to the electric line in series, and a converter module connected on a first side to the electric line in shunt, and a second side of the converter module, opposite to the first side, being connected to the first transformer; wherein the converter module comprises a shunt connected converter with an alternating current, AC, side which is the first side of the converter module, and the converter module further comprises a series connected converter with an AC side of the series connected converter which is the second side of the converter module, wherein a direct current, DC, side of the shunt connected converter is connected to a DC side of the series connected converter by a DC link, the method comprising: generating one or more electric perturbations in the electric line; obtaining: a first voltage of the electric line at a first point of common coupling, PCC, where the shunt connected converter module is connected to the electric line in shunt, wherein the first voltage is influenced by the one or more electric perturbations, a second voltage of the electric line at a second PCC, where the first transformer is connected to the electric line, wherein the second voltage is influenced by the one or more electric perturbations, and/or a first current of the electric line at the second PCC, wherein the first current is influenced by the one or more electric perturbations; and determining an impedance and/or an admittance based on at least one of the one or more electric perturbations, and the obtained one or more of the first voltage, the second voltage and the first current.

A power transformer (1) comprising a plurality of active components (11) immersed in a fluid (3), a tank (51), and an expansion vessel (52) connected to the tank (51) is specified, wherein a volume (2) in the expansion vessel (52) comprises a porous filler material (4) configured to dampen a sloshing motion of the fluid (3) within the volume (2).