Abstract:
An electrical system for controlling a wind turbine is provided. The electrical system includes a first resistive element, a storage element and a controller. The first resistive element and the storage element are coupled to a DC link of the wind turbine. The controller is used for switching between the first resistive element and the storage element in response to a grid side fault condition to minimize mechanical loads induced by the grid side fault condition.
Abstract:
A power dissipating arrangement for dissipating power from a generator in a wind turbine is provided. The generator comprises a plurality of output terminals corresponding to a multi-phase output. The power dissipating arrangement comprises a plurality of dissipating units, a plurality of semiconductor switches, a trigger circuit for switching the semiconductor switches and a control unit for controlling the operation of the trigger circuit, thereby controlling the switching of the semiconductor switches. Each dissipating unit includes a first terminal and a second terminal. The first terminal of each dissipating unit is coupled to each output terminal of the generator. Each semiconductor switch includes a first terminal anode, a second terminal and a gate terminal. The first terminal of each semiconductor switch is coupled to the second terminal of each dissipating unit and the second terminal of the semiconductor switch is coupled to the second terminal of another dissipating unit, such that the second terminal of each dissipating unit is coupled to the first terminal of one semiconductor switch and the second terminal of another semiconductor switch. The trigger circuit is coupled to the gate terminal of the plurality of the semiconductor switches for switching the semiconductor switches.
Abstract:
A structure of the terminals of a brushless motor, which enables the motor to be thin and enables the windings of the motor to be connected to a circuit base board easily and automatically. The brushless motor comprises a rotor section, a stator section, a driving circuit (18), a terminal (6), and a core holder (5). The rotor section has a rotor magnet (7). The stator section has a winding (4) opposed to the rotor magnet (7) in the radial direction of the motor and has a stator core (3) around which the winding (4) is wound. The driving circuit (18) is formed on the surface of a circuit base board (9) electrically connected to the winding (4) wound around the stator core (3). Each terminal (6) has a holder (6b) and a connection part (6c). The holder (6b) holds the winding (4) and is electrically connected to the winding (4). The connection part (6c) is electrically connected to a land part (19) of the driving circuit (18). The core holder (5) holds the terminals (6). The terminals (6) are provided on the surface of the core holder (5), the surface being opposed to the circuit base board (9). At least the holder (6b) and the connection part (6c) are in parallel with the circuit base board (9), and the connection part (6c) is nearer to the circuit base board (9) than the clip-type holder (6b).
Abstract:
A method for controlling a wind power plant, the wind power plant including a plant controller for controlling a plurality of wind turbine generators. The method for controlling a wind power plant allows the wind power plant to continue operating through a grid fault in a weak grid environment. In the method, a fault recovery process is carried out with a wind turbine power controller during a wind turbine fault recovery state to determine a grid voltage (VWTG), compare the grid voltage to a predetermined reference voltage (Vref) to obtain a difference value, and determine a current reference (QrefVC) based on the difference value for generating a reactive current (Idref) for regulating the grid voltage to the predetermined reference grid voltage. A corresponding wind power plant is further provided.
Abstract:
Verfahren und Einrichtung zum Schutz vor Überspannungen in Gleichstromnetzen, insbesondere in den Netzen von U-Booten, wobei in den Inselnetzen, insbesondere in dem Bordnetz von U-Booten, durch rückspeisende Verbraucher verursachte Überspannungen durch aktiv wirkende Schaltungsmaßnahmen herabgesetzt werden.
Abstract:
A vehicle power supply management system includes a load absorbing device that absorbs an excess voltage from the vehicle battery. Under circumstances, such as at vehicle shutdown when an excess voltage spike occurs at the battery, the load absorbing device is selectively coupled to the battery to absorb the excess voltage and protect other electronic components on the vehicle. In one example, a comparator compares the voltage on the battery to a preselected threshold value. Whenever the battery voltage exceeds the threshold, the inventive arrangement selectively couples a load absorbing device, such as a plurality of glow plugs, heating elements within a vehicle seat or a window defrost unit, for example, to the vehicle battery to absorb the excess voltage.
Abstract:
The invention relates to an overvoltage protection device for protecting an electrical installation from overvoltage. Said electrical installation has a vehicle electrical system supplied by an electric generator (9), and electrical devices connected thereto. Said overvoltage protection device comprises a limiting device with a threshold value above the nominal voltage of the generator.
Abstract:
A hybrid alternator includes a stator (10) and a rotor (20), with the rotor (20) having longitudinally separate wound field (24) and permanent magnet (38) rotor portions. A rotor excitation circuit applies a forward polarity to the wound field rotor portion (24) to increase output in a boosting mode at low RPMs and a reverse polarity to decrease output at high RPMs in a bucking mode to maintain a constant voltage output. Alternative embodiments combine a magnetic flux concentrating design for efficient low speed operation with integral strength for high speed capability. Dual voltage output is provided using only one stator winding. A three state voltage regulator allows voltage regulation without inducing reverse currents onto the power bus in the lightly loaded or no battery conditions. The regulator has automatic interlocking to automatically turn on and off without risk.
Abstract:
On propose un systeme de generateur comprenant un generateur avec autoexcitation (1), un regleur de tension (3), un dispositif de transfert (4) pour la prise en charge du courant qui continue a circuler lors de la deconnexion de l'enroulement d'excitation (2) et un dispositif de reception (9) pour absorber l'energie de reaction lors de la coupure d'une charge (11) du generateur. Le dispositif de transfert (4) joue le role de la diode usuelle (13) de libre passage: il presente un cheminement de courant avec une tension de seuil de passage basse commutable sur une tension de seuil elevee. En fonctionnement normal du generateur (1) le bobinage d'excitation (2) est connecte sur le cheminement avec la tension de seuil de passage basse. Lorsque la charge (11) est separee du generateur, le bobinage d'excitation (2) est connecte au cheminement avec la tension de rupture elevee. Le courant d'excitation decroit rapidement. Ainsi l'energie de reaction qui doit renforcer la protection du reseau de bord (9) est fortement diminuee.
Abstract:
Die Erfindung betrifft ein Verfahren (100) zum Ansteuern einer zumindest generatorisch betreibbaren, mehrphasigen elektrischen Maschine (1), deren Phasenanschlüsse (U-Y) in einem aktiven Brückengleichrichter (2) jeweils über ein- und ausschaltbare, steuerbare erste Stromventile (UL-YL) an einen ersten Gleichspannungsanschluss (B-) und über zweite Stromventile (UH-YH) an einen zweiten Gleichspannungsanschluss (B+) angebunden sind, wobei das Verfahren umfasst, in einem generatorischen Betrieb der elektrischen Maschine (1) die ersten Stromventile (UL-YL) einzuschalten, wenn eine Ausgangsspannung zwischen dem ersten Gleichspannungsanschluss (B-) und dem zweiten Gleichspannungsanschluss (B+) zu einem Überschreitungszeitpunkt einen oberen Schwellwert überschritten hat, und die ersten Stromventile (UL-YL) erst wieder auszuschalten, nachdem die Ausgangsspannung danach zu einem Unterschreitungszeitpunkt einen unteren Schwellwert unterschritten hat. Es ist vorgesehen, dass die ersten Stromventile (UL-YL) nach dem Unterschreitungszeitpunkt einzeln und jeweils erst dann wieder ausgeschaltet werden, wenn jeweils ein Indikationswert, der einen Stromfluss in dem dem jeweiligen Stromventil zugeordneten Phasenanschluss (U-Y) kennzeichnet, eine vorbestimmte Eigenschaft aufweist. Mittel zur Implementierung eines entsprechenden Verfahrens sind ebenfalls Gegenstand der vorliegenden Erfindung.