Abstract:
It is described an arrangement (100, 200) for reactive power compensation at an electric energy transmission line (101), the arrangement comprising: at least one first reactive power compensation device (103, 203) each comprising a first type of power electronic switches; at least one second reactive power compensation device (105, 205) each comprising a second type of power electronic switches; and a transformer (107) having a first secondary coil (109) connected to the first device (103) and having a second secondary coil (113) connected to the second device (105) and having a primary coil (117) connectable to the electric energy transmission line (101), the primary coil (117) having more windings than any of the first and second secondary coils (109, 113).
Abstract:
Apparatuses, method and systems featuring model predictive voltage and VAR controls with coordination with and optional optimization of autonomous reactive power control such as autonomous distributed energy resource and/or autonomous switched capacitor banks One embodiment includes an electronic control system structured to construct a linearized model of the power distribution system including a plurality of predetermined nodes, operate a model predictive controller to identify optimized control commands using an objective function defined over a plurality of future scenarios over a look ahead time horizon and a plurality of constraints, and transmit the identified control commands to control operation of at least the voltage regulators and the switched capacitor banks.
Abstract:
A method for controlling a modular converter (16) connected to an electrical grid (12) for active power filtering the electrical grid (12) to compensate for a load (14) connected to the electrical grid (12), comprises: receiving an actual load current (ii) and an actual converter state (x) of the modular converter (16); determining, from the actual load current and a history of previous load currents, a sequence of future load currents over a prediction horizon (40); predicting a sequence of future converter states of the modular converter (16) and a sequence of manipulated variables (U) for the modular converter (16) over the prediction horizon (40) by solving an optimization problem based on the actual converter state (x) and the future load currents by minimizing an objective function mapping control objectives to a scalar performance index subject to the dynamical evolution of a prediction model of the modular converter (16) and subject to constraints (42); and applying a next switching state, which is determined from a first element of the sequence of manipulated variables (U), to the modular converter (16).
Abstract:
The objective of this patent is to describe novel methods and device systems for detecting the fault-cleared state in a shunt compensated transmission line. The methods are applicable in all types of transmission line types and faults, in any type of reclosure mechanism, and can be implemented in existing devices such as relays and not need sophisticated equipment. One application of detecting the fault-cleared state is adaptive reclosure in which case, substantial improvement in transmission system reliability and benefits in protection can be achieved.
Abstract:
The invention relates to a receiver for a wireless power transmission, comprising a receiving coil for generating an electric current when the receiving coil is subjected to an electromagnetic alternating field, and a consumer for receiving the generated electric current. Reactive power compensation is provided in order to approximate the flow of the electric current through the receiving coil to a sinusoidal shape.
Abstract:
Ein Empfänger für eine drahtlose Energieübertragung umfasst eine Empfangsspule zur Erzeugung eines elektrischen Stroms, wenn die Empfangsspule einem elektromagnetischen Wechselfeld ausgesetzt ist, und einen Verbraucher zur Aufnahme des erzeugten elektrischen Stroms. Dabei ist eine Blindleistungskompensation vorgesehen, um den Verlauf des elektrischen Stroms durch die Empfangsspule einer Sinusform anzunähern.
Abstract:
Systems and methods for connecting a power source to switched capacitors are provided. A method may be used in controlling the connection of a multiple phase power source to a plurality of capacitors. Each phase of the multiple phase power source is electrically connectable to at least one of the plurality of capacitors through a switching device. The method comprises, for each phase of the multiple phase power source, determining a first voltage of a power signal for the respective phase of the power source using a first voltage divider that is electrically connected to a first terminal of the switching device for the phase. The method further comprises, for each phase, determining a second voltage across a capacitor that is electrically connected to a second terminal of the switching device for the phase. The second voltage is determined using a second voltage divider that is electrically connected to the second terminal of the switching device for the phase. The method further comprises, for each phase, generating a close signal configured to cause the switching device for the phase to close and electrically connect the respective phase of the power source to the capacitor when the difference between the first voltage and the second voltage is approximately zero.
Abstract:
A presente invenção descreve um método para controle de sobretensões durante a manobra de religamento de linhas de transmissão com compensação reativa em derivação. Após o disjuntor abrir uma LT, a interação entre a admitância transversal da linha e a indutância do reator de compensação reative faz com que a tensão entre os pólos do disjuntor assuma forma oscilatória (batimento). O ponto ótimo para voltar a fechar o disjuntor corresponde à região onde a amplitude do batimento da tensão entro os pólos do disjuntor é mínima. O método desenvolvido apresenta maior segurança na determinação da primeira região de mínimo do batimento, independente da passagem da onda de tensão por zero. Tal procedimento permite também contar com maior margem de tempo para operar o disjuntor já que a detecção da região ótima para o religamento ocorre com vários ciclos de freqüência fundamental de antecedência. Este método deve ser incorporado na lógica de controle de um relé digital para religamento tripolar de linhas de transmissão gerando um novo relé digital para religamento tripolar adaptativo de linhas de transmissão com compensação reativa em derivação.
Abstract:
Electric power saving apparatus for a polyphase alternating current power supply including: one or more line terminals, the or each line terminal for electrical connection to an active conductor of the alternating current power supply; a neutral terminal for electrical connection to a neutral conductor of the alternating current power supply; a capacitor electrically connected to the or each line terminal for capacitive isolation of the or each line terminal from the neutral terminal; a first diode electrically interposed between the or each line terminal and the neutral terminal and having electrical resistance means electrically interposed between the or each first diode and its line terminal; and a second diode electrically interposed between the or each line terminal and the neutral terminal and having electrical resistance means electrically interposed between the or each second diode and the neutral terminal.