Abstract: The present invention relates to a method for obtaining switching angles (?1, . . . , ?i), and to an associated conversion system. In the method, possible values (IM) are established for a modulation index, within a predetermined range of values (R) and divided into a plurality of segments (S1, . . . , Sj); a value is obtained for each of the switching angles (?1, . . . , ?i) in each segment (S1, . . . , Sj) and for each of the possible values (IM); a switching curve (SC) is formed for each switching angle (?1, . . . , ?i) over the entire range (R); and the height or amplitude and the slope of each switching curve (SC) at a possible value shared by two segments (S1, . . . , Sj) are considered constant.

Abstract: An output filter for a power conversion system having a plurality of power converters connected in parallel, the output filter including a magnetic core and a plurality of filtering windings each wound around a corresponding one of a plurality of segments of the magnetic core and corresponding to one of the plurality of power converters, each of the plurality of filtering windings including a free-end configured for connection to an output of a corresponding one of the plurality of power converters and a second end, the second ends of all of the filtering windings being electrically connected to each other in a common connection; at least one additional winding wound around the additional segment of the magnetic core, the additional winding having a free-end for being connected to an electrical grid and a second end connected to the common connection.

Abstract: Power conversion systems and an associated control methods are disclosed. The system includes a plurality of converters connected in parallel on an AC side, each converter includes an AC side for being coupled to a power grid, a DC side for being coupled to a DC source, and a first terminal and a second terminal on said DC side. The outputs on the AC side of all the converters are connected to a common output point, the first terminals of the different converters of the system being grounded, and the second terminals of said converters being independent to one another. Each source is therefore adapted and configured to work independently of the rest of the sources.

Abstract: The invention relates to a conversion system (100) with a DC side and an AC side, and to an associated control method. The system (100) comprises a primary conversion block (1), a secondary conversion block (2) and a transformer block (3) with at least one primary winding (3.1) connected to the primary conversion block (1) and a secondary winding (3.2R, 3.2S, 3.2T) for each phase (R, S, T) which are connected to the secondary conversion block (2). Each conversion block (1, 2) comprises a plurality of controllable switches, and the system (100) comprises a controller (4) communicated with said switches and configured for causing the opening and closing of said switches in a controlled and coordinated manner.

Abstract: A method which is suitable for a system having a frequency converter and a generator, both of which are connected to a power grid, includes obtaining sub-synchronous components of the grid voltage and determining damping current set points according to the sub-synchronous components to compensate for sub-synchronous resonances of the grid. Damping current set points are determined by receiving the sub-synchronous components of the grid voltage and returning damping current set points as outputs. A variable damping gain is adjusted according to the sub-synchronous frequency of the grid, such that the required compensation level can be adapted to the frequency converter for damping sub-synchronous resonance of the grid.

Abstract: The present invention relates to an electric energy conversion method and system with at least two conversion units (14), comprising control means (12) establishing the maximum output current of the operative conversion modules, as well as the commutation frequency of the entire or of a sub-group of the operative conversion modules to thus increase the availability of the conversion system in the event of failures.

Abstract: An output filter for a power conversion system having a plurality of power converters connected in parallel, the output filter including a magnetic core and a plurality of filtering windings each wound around a corresponding one of a plurality of segments of the magnetic core and corresponding to one of the plurality of power converters, each of the plurality of filtering windings including a free-end configured for connection to an output of a corresponding one of the plurality of power converters and a second end, the second ends of all of the filtering windings being electrically connected to each other in a common connection; at least one additional winding wound around the additional segment of the magnetic core, the additional winding having a free-end for being connected to an electrical grid and a second end connected to the common connection.

Abstract: Power conversion systems and an associated control methods are disclosed. The system includes a plurality of converters connected in parallel on an AC side, each converter includes an AC side for being coupled to a power grid, a DC side for being coupled to a DC source, and a first terminal and a second terminal on said DC side. The outputs on the AC side of all the converters are connected to a common output point, the first terminals of the different converters of the system being grounded, and the second terminals of said converters being independent to one another. Each source is therefore adapted and configured to work independently of the rest of the sources.

Abstract: A filtering method for the alternating current side of a power conversion system by a filter circuit, and system that includes the filter circuit. Said filter circuit includes a filter capacitor circuit and a damping circuit connected to the filter capacitor circuit. Upon determining that the power conversion system operates under steady state conditions, the damping circuit of the filter circuit is caused to present a first impedance value for the current that flows through said damping circuit, and upon determining that the power conversion system is operating under transient state conditions, said damping circuit is caused to present a second impedance value for said current.

Abstract: A kit for a wind station having a fixed speed wind turbine with a generator configured to be coupled to a grid by a coupling device so that the turbine operates at a fixed frequency equal to the frequency of the grid. The kit includes a back-to-back power converter configured for connection between the generator and the grid, and the power converter includes a machine side converter, a grid side converter and a DC link between both converters, a controller for controlling the power converter, and a connection point for receiving at least one parameter of the generator of the turbine. The connection point is communicated with the controller, and the controller is configured to act upon the power controller depending on said parameter.

Abstract: A wind turbine that includes a housing, an asynchronous generator disposed in the housing and configured to be electrically connected to a power grid connection; a power converter circuit disposed in the housing and configured to be electrically connected to the asynchronous generator; and a variable impedance device disposed in the housing, connected to the generator and configured to limit current by varying impedance in response to a transient current. The wind turbine delivers reactive power to the power grid when the variable impedance device varies impedance in response to the transient current. The variable impedance device can be arranged in series between the asynchronous generator and the power grid connection, or can be in a shunt arrangement between the asynchronous generator and a neural point.

Abstract: A filtering method for the alternating current side of a power conversion system by a filter circuit, and system that includes the filter circuit. Said filter circuit includes a filter capacitor circuit and a damping circuit connected to the filter capacitor circuit. Upon determining that the power conversion system operates under steady state conditions, the damping circuit of the filter circuit is caused to present a first impedance value for the current that flows through said damping circuit, and upon determining that the power conversion system is operating under transient state conditions, said damping circuit is caused to present a second impedance value for said current.

Abstract: The object of the invention is to provide a power supply system and method for the various elements forming DC/AC electronic power converters that assures the operation of the converters during normal operating conditions and anomalous operating conditions, being specially designed for photovoltaic systems connected to the power grid and capable of providing direct current and alternating current voltages at the output thereof from at least one DC power source (1) and at least one AC power source (2), which basically comprises an output for DC loads (6) connected to the output of a DC/DC converter (3) the input of which is connected to the DC power source (1), an AC output for critical loads (7) connected to a first selector (5) configured for alternating between a first position where said AC output for critical loads (7) is connected to the output of a first DC/AC converter (4) the input of which is connected to the DC power source (1), and a second position where said AC output for critical loads (7) is co

Abstract: Synchronization system and method for a power generation unit coupled to an electrical power system, in order to facilitate the synchronization between the power generation unit and the electrical power system. A synchronization signal (SS) is generated by means of at least one Phase-Locked Loop (4) from a main electrical signal (Se) received from the electrical power system. The Phase-Locked Loop (4) comprises a controller scheme with a plurality of gain parameters (Kmn) to eliminate at least some of the deviations of the synchronization signal (Ss) in respect of the main electrical signal (Se), and said gain parameters (Kmn) are adjusted depending on the frequency and the amplitude of said main electrical signal (Se).

Abstract: A method which is suitable for a system having a frequency converter and a generator, both of which are connected to a power grid, includes obtaining sub-synchronous components of the grid voltage and determining damping current set points according to the sub-synchronous components to compensate for sub-synchronous resonances of the grid. Damping current set points are determined by receiving the sub-synchronous components of the grid voltage and returning damping current set points as outputs. A variable damping gain is adjusted according to the sub-synchronous frequency of the grid, such that the required compensation level can be adapted to the frequency converter for damping sub-synchronous resonance of the grid.

Abstract: Verifying system and method for verifying the disconnecting means of a DC/AC converter which are connected in series through a midpoint in each phase between the converter and a power grid. The system comprises voltage detectors and a control unit in communication with said detectors and configured for determining the status of the disconnecting means depending on said voltages. The detectors comprise a detector associated with each phase for measuring the voltages between the corresponding midpoint and the neutral of the power grid, and an additional detector for measuring the voltage between said neutral and a reference point of the converter.

Abstract: The present invention relates to an electrochemical cell (20) comprising a bipolar plate (26); an annular support next to the bipolar plate (26); a first electrode (22) separated from the bipolar plate (26) defining a first half-cell (10?) (cationic or anionic) together with the plate and the annular support. The cell also has a membrane (23) next to the first electrode (22); a second electrode (24) next to the membrane (23); and a closure element (21) defining a second half-cell (10?) (cationic or anionic depending on the nature of the second electrode) together with the second electrode (24). In the present invention the closure element (21) is housed within the annular support (25).

Abstract: Synchronization system and method for a power generation unit coupled to an electrical power system, in order to facilitate the synchronization between the power generation unit and the electrical power system. A synchronization signal (SS) is generated by means of at least one Phase-Locked Loop (4) from a main electrical signal (Se) received from the electrical power system. The Phase-Locked Loop (4) comprises a controller scheme with a plurality of gain parameters (Kmn) to eliminate at least some of the deviations of the synchronization signal (Ss) in respect of the main electrical signal (Se), and said gain parameters (Kmn) are adjusted depending on the frequency and the amplitude of said main electrical signal (Se).

Abstract: Kit and method for a wind station comprising a fixed speed wind turbine with a generator being coupled to a grid by means of a coupling device so that the turbine operates at a fixed grid current frequency of the grid. The kit (100) is adapted to be coupled between the generator (10) of the wind turbine (1) and the grid (2), replacing at least the coupling device, the kit (100) turning the fixed speed wind turbine into a variable speed wind turbine.

Abstract: The present invention relates to an energy conversion circuit comprising a switching stage with a positive DC voltage terminal (1), a negative DC voltage terminal (3), m?1 intermediate DC voltage terminals (2) m DC bus capacitors (5); and p linked cells consisting of m+1 switches (9) and at least one capacitor (10), connecting cell 1 to the positive DC voltage terminal (1), negative DC voltage terminals (3) and intermediate DC voltage terminals (2); and a multilevel converter, the output of which is connected to the AC voltage terminal (4), with a positive voltage terminal (12) and a negative voltage terminal (14) of the multilevel converter and m?1 intermediate voltage terminals of the multilevel converter (13), which are connected to the positive output terminal of the switching stage (6), to the negative output terminal of the switching stage (8), and to the m?1 intermediate output terminals of the switching stage (7), respectively.