Abstract: The invention controls the network frequency via an active power reserve obtained by interacting in a coordinated manner with the speed regulation that acts on the power generated or on the pitch angle, to guarantee primary or secondary regulation across the whole range of wind speed.

Abstract: The present invention relates to a method and system for controlling a wind power installation connected to an electrical power grid, in case of a fault in said grid. In the electrical machines that form part of the wind power installation, generators and transformers, it is possible to change the impedance of the neutral closure introducing a plurality of active and passive elements. This limits the currents during the grid fault, thereby reducing the peak torque in the mechanical train of the wind turbines and allows guaranteeing compliance with the network connection requirements, as control of the active and reactive currents is maintained at all times.

Abstract: A control method for multi-converter systems wherein all DC/AC converters (1.1-1.n) are connected to a single transformer (2) via a single primary winding. The method of the present invention stands out mainly because it controls the common-mode voltage generated by the different DC/AC converters (1.1-1.n) so that said voltage falls mainly on the transformer (2).

Abstract: It allows connecting or disconnecting polyphase conversion stages (2a, 2b), comprising at least two polyphase back-to-back conversion stages (2a, 2b) connected between a rotary electric machine (3) and the power grid (4), each of these stages having two converters and one DC bus (6a, 6b); at least as many switching cells in each phase as there are conversion stages (2a, 2b), wherein at least one of the cells is associated to each of the conversion stages (2a, 2b); cut-off means (7) between the DC buses (6a, 6b) of the at least two polyphase conversion stages (2a, 2b); cut-off means (8a, 8b) between the at least two conversion stages (2a, 2b) and the rotary electric machine; and cut-off means (9a, 9b) between the at least two polyphase conversion stages (2a, 2b) and the power grid (4).

Abstract: The invention describes a system and a method for controlling an electric generator connected to the power grid during a voltage drop in the power grid, the system comprising a back-to-back converter (2) connected between the generator (3) and the power grid (4) and also, in parallel to the generator side converter (2a), rectifying means (5) connected in series between the generator (3) and the DC-link (2b) of the back-to-back converter (2), thus providing an alternative way for the energy excess at the generator side to enter the DC-link (2b).

Abstract: System for producing electric energy and hydrogen based on renewable energy sources, such as wind energy from one or several wind turbines, and incorporating means for producing hydrogen. The system comprises a hybrid electrolyzer device, which comprises a combination of at least two different electrolysis technologies and at least one control device, which manages the hydrogen production between the two electrolyzers of the different electrolysis technologies; being at least one electrolyzer of a rapid dynamics electrolysis technology type and, at least the second one of a substantially slower dynamics electrolysis technology type.

Abstract: Electric circuit for converting direct into alternating current specially designed for photovoltaic systems connected to the electrical grid without a transformer, and enabling the earthing of one of the input terminals (2) of the photovoltaic generator, thereby working with a wide range of input voltages and having a high efficiency.

Abstract: An apparatus and method of controlling a frequency converter is provided. First, subsynchronous components in the electrical grid are identified using voltage measurements of the electrical grid. The subsynchronous components of the electrical grid are then used to determine set points for damping currents. These damping currents are then added to current set points calculated by power regulation loops to generate total current set points. Thereafter, the frequency converter is controlled based on the total current set points.

Abstract: The invention comprises a doubly-fed generator (2), the rotor thereof is connected to the power grid (3) by a back-to-back converter (4) and the stator thereof is connected to the power grid (3), essentially standing out for additionally comprising at least one first additional impedance (5) connected in parallel between the generator (2) rotor and the back-to-back converter (4); at least one second additional impedance (6) connected to the generator stator (2); and at least one control unit capable of governing the additional impedances (5, 6).

Abstract: The object of the invention is to provide an energy management system for variable resource energy generating systems, which incorporates means for the storing of energy and the management thereof. The system permits the needs which arise in the power grid to be met, and participates in the regulation of the power grid and contributing to the stability and quality thereof.

Abstract: A variable speed wind turbine having a doubly fed induction generator (DFIG), includes an exciter machine mechanically coupled to the DFIG and a power converter placed between a rotor of the DFIG and the exciter machine. Thus, the power converter is not directly connected to the grid avoiding the introduction of undesired harmonic distortion and achieving a better power quality fed into the utility grid. Moreover, the variable speed wind turbine includes a power control and a pitch regulation.

Abstract: A power-management system and method for photovoltaic installations connecting to the grid incorporates monitoring active and/or reactive power, account being taken at all times of grid requirements, in order to allow temporary demand arising in the grid to be addressed, thereby contributing to regulation of the grid and to the stability and quality thereof.

Abstract: A variable speed wind turbine having a doubly fed induction generator (DFIG), includes an exciter machine mechanically coupled to the DFIG and a power converter placed between a rotor of the DFIG and the exciter machine. Thus, the power converter is not directly connected to the grid avoiding the introduction of undesired harmonic distortion and achieving a better power quality fed into the utility grid. Moreover, the variable speed wind turbine includes a power control and a pitch regulation.

Abstract: A variable speed wind turbine having a doubly fed induction generator (DFIG), includes an exciter machine mechanically coupled to the DFIG and a power converter placed between a rotor of the DFIG and the exciter machine. Thus, the power converter is not directly connected to the grid avoiding the introduction of undesired harmonic distortion and achieving a better power quality fed into the utility grid. Moreover, the variable speed wind turbine includes a power control and a pitch regulation.