Hitachi Energy

A high impedance fault (HIF) may cause a section of a power line to burn open. When the fault current is in the same order of magnitude as the normal load current, the protection device that is upstream from the faulted power line will not trip, which may make it difficult to quickly identify the location of the faulted power line. Accordingly, disclosed embodiments leverage advanced metering infrastructure (AMI) data in a weighted least squares (WLS) distribution state estimation to estimate a state of the power network. The estimated states from successive WLS distribution state estimations may be used to calculate power-flow drops, which are used to define the search space for the faulted power line. From this search space, a single power line may be identified as the faulted power line, such that remedial action(s) may be performed to resolve any resulting power outages.

In one embodiment, the bi-mode insulated gate transistor (1), BiGT, comprises: - a pilot region (21) and a mixed region (22) at a bottom side (20), - a first region (31) at a top side (30) opposite the bottom side (20) and atop the pilot region (21), and a second region (32) at the top side (30) and atop the mixed region (22), wherein - the first region (31) and the second region (32) are each provided with a gate electrode (41, 42), and - the gate electrodes (41) in the first region (31) and in the second region (32) are electrically addressable independent from one another.

An electric power converter (1) comprising an enclosure (2) and a plurality of devices (3) that generate heat during operation and are located inside the enclosure (2), wherein- and enclosure (2) comprises an air inlet opening (21) and an air outlet opening (22),- the enclosure (2) is airtight except for the air inlet opening (21) and the air outlet opening (22),- the air inlet opening (21) is configured to be connected to an air mover (41) creating a positive pressure,- an air distribution manifold (51) is located inside the enclosure (2) and connected to the air inlet opening (21), and- the air distribution manifold (51) has air openings (6) directed towards the devices (3).Further, an electric appliance (10) is specified.

The invention relates to a transformer assembly (2) which comprises a panel radiator (4) provided at least on one side of the transformer assembly (2), and at least one external reinforcement structure (14, 1401, 1402, 1403, 1404, 1405). The panel radiator (4) comprising a first panel (6) and a second panel (8), wherein the second panel (8) and the first panel (6) are joined along a circumferential edge area (10) of the panel radiator (4) to form an internal space (12) configured to accommodate oil for cooling the transformer assembly. The at least one external reinforcement structure (14, 1401, 1402, 1403, 1404, 1405) is to reinforce at least a portion of the circumferential edge area (10). The external reinforcement structure (14) is provided on at least a lateral region (16, 18) and/or an upper region (20) of the circumferential edge area (10).

The present disclosure relates to a system (100) for controlling communication between a first protection system (PS_A) at a first substation (10_A) of an electrical power network (EPN) and a second protection system (PS_B) at a second substation (10_B) of the electrical power network (EPN), wherein the first substation (10_A) and the second substation (10s) are each electrically connected to a power line (PL), wherein a first protection relay (R_A) of the first protection system (PS_A) and a second protection relay (R_B) of the second protection system (PS_B) provide differential protection, the system (100) comprising: a communication network (1000), the system (100) is configured to: communicate critical data and non-critical data between the first protection system and the second protection system via said plurality of communication paths, wherein said critical data comprises first source data (SD_A) representing a first power line measurement of the power line (PL) at the first substation (10_A), and/or second source data (SD_B) representing a second power line measurement of the power line (PL) at the second substation (10_B), wherein the system (100) further comprises: at least one traffic shaper configured to control at least one network parameter associated with at least one node of said communication network to provide from said plurality of communication paths at least one traffic-shaped communication path in which communication of critical data is prioritized over non-critical data. An electrical power network (EPN) comprising the system and a method of controlling differential protection communication are also disclosed.

The present disclosure relates to a device for providing unifying control of a plurality of converters. The device comprises a central controller configured to obtain current and voltage measurements at at least one reference point, a plurality of local controllers each associated with one of a plurality of converters and each configured to obtain a current and voltage measurement of the respective converter and a plurality of unifying controllers each associated with one of the plurality of converters and configured to provide unifying control of the converters based on control signals of the central controller and/or the respective local controller. The disclosure further relates to a corresponding system, method, storage medium and computer program product.

The present disclosure relates to a protection assisting device (100) configured to communicatively connect to a first protection system (PS<A>) at a first substation (10<A>) of an electrical power network (EPN) and a second protection system (PS<B>) at a second substation (10<B>) of the electrical power network (EPN), the first substation (10<A>) and the second substation (10<B>) electrically connected to a power line (PL), the first protection system (PS<A>) and the second protection system (PS<B>) communicatively connected via a primary communication network (1001), said first protection system (PS<A>) and said second protection system (PS<B>) cooperating to provide differential protection via a respective first protection relay (R<A>) and a second protection relay (R<B>) based at least on a first power line measurement of the power line (PL) at the first substation (10<A>) and a second power line measurement of the power line (PL) at the second substation (10<B>). The protection assisting device (100) is configured to provide protection assisting information to the first protection relay and the second protection relay based on one or more predetermined protection assistance conditions determined from operational data received from the first protection system and the second protection system via a secondary communication network different from the primary communication network, which secondary communication network is a nondedicated communication network. The present disclosure also relates to a protection assisting system, an electrical power network, and a method of providing differential protection assistance.

A cooling profile (10) for a transformer comprises an elongated shape with a predetermined length (L) along a longitudinal axis (A) and a first contact portion (11) and a second contact portion (12). Both contact portions (11, 12) are configured to be coupled to an associated first winding (1) or second winding (2) of the transformer. A middle web (18) connects the first and the second contact portions (11, 12) along a transverse axis (B) transverse to the longitudinal axis (A). The cooling profile (10) further comprises a fin structure (20) including at least one protrusion (21) arranged on the middle web (18) between the first and the second contact portion (11, 12) along the transverse axis (B) such that the fin structure (20), the first contact portion (11) and the second contact portion (12) form a plurality of cooling channels (17) opened along the longitudinal axis (A).

A transformer (1) comprises a tank (2) forming a housing of the transformer (1), an active part (3, 4) including electric components for transforming voltage, and a cooling fluid (5) for cooling the active part (3, 4) during operation of the transformer (1). The transformer (1) further comprises a cushion element (7) comprising an elastomer material. The active part (3, 4) is immersed in the fluid (5) inside the tank (2), and the cushion element (7) is arranged inside the tank (2) between a tank bottom (9) and the active part (3, 4) with respect to an upright longitudinal axis (L) of the transformer (1).

The present disclosure relates to a method for fault detection and fault localisation on a power transmission line. The method comprises obtaining a fault location of a fault on the power transmission line, obtaining, by an unmanned aerial vehicle (UAV), image and/or video and/or audio data of the fault at the fault location, and identifying, by analysing the image and/or video and/or audio data, a fault condition.