Abstract: A method of short-circuiting a faulty submodule for a voltage-source power converter is disclosed. The submodule is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches with anti-parallel freewheeling diodes and optionally non-controllable semiconductor valves. The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode. The method further includes selecting a minimum number of power semiconductor switches suitable to provide a bypass path through the submodule depending on the identified faulty semiconductor device and the determined failure mode and driving the selected power semiconductor switches by a modified driving voltage compared to normal operation to cause them to break down in order to provide a durable, stable, low impedance short-circuit path between the AC voltage terminals of the submodule.

Abstract: A modular multipoint power converter for converting an AC voltage to a DC voltage or vice versa, and a method of operating it are provided. The multipoint power converter has a converter branches, whereby two converter branches are connected to each other respectively to form a phase branch of the converter. Each converter branch has a plurality of similar submodules, each of which is formed from a half-bridge circuit with power semiconductor switches. The branch currents through the converter branches are controlled in operation by increasing the DC component of the DC current or the DC intermediate circular current such that a unipolar current flows through the converter branches. As a result, with the same plurality of submodules per converter branch, the transmissible power can be increased, the power semi-conductor elements can be better utilized, or the plurality of submodules can be reduced while the transmissible power remains the same.

Abstract: The invention relates to a power system with an electric circuit connected between a power grid and a power source. The electric circuit includes a main power converter having main input terminals connected to the power source 16 by a DC link and output terminals. The main power converter is controlled by a controller. The electric circuit includes a main transformer having a primary winding 8a and a secondary winding, the primary winding being connected to the output terminals of the main power converter. Main switchgear is connected between the secondary winding of the main transformer and the power grid. An auxiliary transformer has a primary winding connected to the power grid in parallel with the main switchgear and a secondary winding connected to the controller. A pre-charge circuit is connected between the auxiliary transformer and the DC link.

Abstract: A method (36) of short-circuiting a faulty submodule (12, 12?, 12?) for a voltage-source power converter (8) is disclosed. The submodule (12, 12?, 12?) is based on a full-bridge, asymmetric full-bridge or half-bridge circuit design having power semiconductor switches (T1-T4) with anti-parallel freewheeling diodes (D1-D4) and optionally non-controllable semiconductor valves (D1?-D4?). The method 36 includes identifying a faulty semiconductor device and determining a failure mode selected from a short-circuit failure mode and an open circuit failure mode.

Abstract: There is provided a system for analyzing and controlling a productivity of a drilling apparatus. The exemplary system includes a processor and a memory including instructions that cause the processor to perform certain operations. The operations can include receiving information from a control system of the drilling apparatus and determining a key performance metric based on the information. The operations can further include performing a comparison between the key performance metric and at least one other key performance metric. Furthermore, the operations can further include instructing, based on the comparison, the control system to alter the productivity of the drilling apparatus.

Abstract: There are provided control systems and methods for charging batteries. For instance, there is provided a system for charging at least two batteries. The system can include a set of hardware associated with the at least two batteries, and the at least two batteries can be connected in series. Each battery from the at least two batteries can be associated with a subset of the set of hardware, and one subset of the set of hardware can be configured to control an associated battery independently from another subset of the set of hardware and its associated battery.

Abstract: Element of a rotating electrical machine, of the rotor or stator type, comprising a plurality of stacks of magnetic sheets each equipped with a tooth comprising notches intended to accommodate electrical windings, and pins arranged between two successive bundles of sheets forming an air-flow duct. A portion of the pins is distributed asymmetrically on the tooth of the stator or rotor sheet with respect to a median axis of the width of the tooth.

Abstract: A power distribution system includes power converter systems electrically connected to a distribution bus which defines a point of common coupling. Each power converter system includes a power converter with semiconductor switching devices controlled using a pulse width modulation strategy with a switching frequency. A controller for each power converter system applies a spectrum analysis process to the respective power converter system that uses measured or derived zero sequence currents associated with the respective power converter system to determine the location of a ground fault within the power distribution system. Each controller applies a switching frequency process where the switching frequency of the power converter of at least one of the power converter systems is different from the switching frequency of the power converter of at least another one of the power converter systems during at least part of the time that the spectrum analysis process is applied.

Abstract: Provided is a power distribution system that includes a reconfigurable DC/DC power converter configured to be connected with an energy storage device at an input end for receiving an input voltage therefrom, and a power electronics building block having a primary bridge unit, a secondary bridge unit magnetically connected with the primary bridge unit, and an outer bridge unit at an output end and connected to an output of the secondary bridge unit, configured to output an output voltage.

Abstract: The invention relates to a supply system for a plurality of loads connected in parallel to a direct current supply bus. The supply system includes a DC supply bus and a plurality of supply lines connected in parallel to the supply bus and supplying the said loads. The supply system includes uncoupling and damping means that is adapted to decrease the unipolar signals travelling within the supply system while the loads are being supplied. The uncoupling and damping means includes at least one inductance arranged in series in at least one of the supply lines. Protective means (are also provided for protection in the event of a fault.

Abstract: A method, apparatus, and system to control and test a solar inverter are provided. The method commissions a solar inverter of a solar plant before it is placed into power production. The commissioning process verifies that the inverter to be tested is functioning as intended by connecting a first inverter to the inverter to be commissioned, and using the first inverter to emulate the power grid without being connected to the power grid, and circulate reactive and limited active power between the first inverter and the inverter to be commissioned.

Abstract: A method of controlling a power system that includes an electrical machine, e.g., wind turbine generator, a power converter, a DC circuit and a dynamic braking system (DBS) having a braking circuit having a braking resistor and being connected in series to the DC circuit, is provided. The method includes operating the DBS and controlling operation of the electrical machine based on a prevailing temperature of the braking circuit, stopping the electrical machine and controlling the electrical machine to be restarted at its rated output power once the prevailing temperature of the braking resistor reaches or falls below a lower temperature threshold. The electrical machine may be restarted at a lower output power and after restarting, its output power can be increased based on a power starting profile as the braking resistor cools.

Abstract: A stator for an electrical machine (e.g., a motor or generator) is described. The stator includes a stator core consisting of a plurality of axially adjacent generally annular laminations. The stator has axially extending stator teeth between adjacent pairs of which are formed axially extending stator slots for receiving conductors of a stator winding. At least one of the stator teeth includes an axially extending cooling passageway through which a cooling fluid flows in use. The electrical machine can include means for circulating cooling fluid through the cooling passageway(s) to cool the stacked laminations and means for circulating air around the stator along an air cooling circuit where the circulated air is cooled by the stator laminations and there is no need for a separate heat exchanger.

Abstract: There is provided a power converter unit that can include an inverter and a plurality of batteries. The power converter unit can include a battery energy storage system (BESS) and an inverter. The BESS and the inverter can share at least one protection circuit.

Abstract: A power distribution system such as a marine power distribution and propulsion system. The system includes an ac busbar and a plurality of active front end power converters. Each AFE power converter includes a first active rectifier/inverter connected to the busbar and a second active rectifier/inverter connected to an electrical load such as an electric propulsion motor. Power sources are connected to the dc link of the AFE power converters and can be operated under the control of a power management controller or power management system.

Abstract: A rotor for an asynchronous electrical machine comprising a magnetic ring comprising a plurality of layers of ferromagnetic metal sheets stacked axially and a squirrel cage having a plurality of conductive elements regularly distributed over the periphery of the magnetic ring and each having two opposite ends extending axially beyond the magnetic ring and each connected to a short-circuit crown, arranged axially on either side of the magnetic ring and intended to connect the ends of the conductive elements electrically. The rotor is segmented circumferentially into at least two rotor segments.

Abstract: There are provided methods and systems for interfacing converters and solar power arrays. For example, there is provided a method for interfacing a solar power generation apparatus with an electricity grid. The method can include connecting a first level and a second level of the solar power generation apparatus to a two-level converter. Furthermore, the method can include interfacing the two-level converter with the electricity grid via a four-wire connection.

Abstract: A stator for an electrical machine is described. The stator includes a plurality of axially adjacent generally annular laminations. An axially extending coolant passageway through which a coolant fluid flows in use, extends through the stator. A plurality of axially spaced sealing recesses are provided. Each sealing recess is located between a pair of laminations and is in open communication with the surface of the axially extending coolant passageway. Each sealing recess has an axial width greater than the gap between the facing planar surfaces of axially adjacent laminations and is at least partially filled with a cured resin material to define a plurality of axially spaced seals.

Abstract: Provided is an apparatus, including a capacitor module having a plurality of connecting terminals and a plurality of switch elements. Each switch element has at least one switch terminal coupled to a corresponding connecting terminal, wherein the switch elements are configured for mutually exclusive operation via a control device.

Abstract: Provided are systems and methods for cooling a power converter. For example, there is provided a controller programmed to control a heat transport rate between a coolant disposed in a cooling system and a power converter coupled thereto by regulating a pressure of the coolant in the cooling system.