摘要:
A neutral conductor filter having three transformers. A first transformer has a primary winding connected to a first power conductor and the neutral conductor. A second transformer has a primary winding connected to a second power conductor and the neutral conductor. A third transformer has a primary winding connected to a third power conductor and the neutral conductor. The secondary windings of the transformers are connected in series with each other and a capacitor is connected in parallel with the series connected secondary windings. The capacitor is tuned with the leakage reactance of the transformers so that the impedance to zero-sequence third harmonic current is minimized.
摘要:
A method for operating an electrical machine includes coupling the electrical machine to an electric power system such that the electric power system is configured to transmit at least one phase of electric power to and from the electrical machine. The method also includes configuring the electrical machine such that the electrical machine remains electrically connected to the electric power system during and subsequent to a voltage amplitude of the electric power system operating outside of a predetermined range for an undetermined period of time.
摘要:
A wind turbine generator control system includes relatively fast regulation of voltage near the individual generators with relatively slower overall reactive power regulation at a substation or wind farm level. The setpoint of the relatively fast voltage regulator is adjusted by the relatively slow reactive power regulator. The fast voltage regulation can be at the generator terminals or at a synthesized remote point.
摘要:
A hybrid active power filter having programmed impedance characteristics is presented. In accordance with which, a passive device comprising a capacitor C.sub.F is connected in series with an active device which are together connected in shunt with a power source and a load at transmission lines of a power system. Capacitor C.sub.F substantially supports the full-line voltage V.sub.H of the power source, whereby the active filter is exposed to a substantially lower voltage than the line voltage V.sub.H. The active device includes on active filter, i.e., an inverter current regulator with a programmable controller for executing a control algorithm. The controller of the active device receives signals corresponding to a voltage V.sub.M, at the low side of filter capacitor C.sub.F. Voltage V.sub.M is at a substantially lower voltage than the line voltage V.sub.H, whereby the cost of sensing voltage V.sub.M is significantly less than sensing the high line voltage V.sub.. The control algorithm of the present invention is expressed as ##EQU1## where I.sub.A is the current in the active device and Y.sub.FAo is an order transfer function of the effective admittance of the active device. Y.sub.FAo is a continuous function which is defined to provide a low impedance path at desired frequencies. Accordingly, the control algorithm controls the current I.sub.A in response to voltage V.sub.M sensed at the low side of filter capacitor C.sub.F as dictated by the programmed function. The active device may be connected to the passive filter at a junction between two capacitors or at a junction between two inductors.
摘要:
A method for determining electric currents for an electrical machine includes generating a first real power current demand signal and a first reactive power current demand signal. The method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing a second real power current demand signal over a second reactive power current demand signal. Alternatively, the method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing the second reactive power current demand signal over the second real power current demand signal. The method further includes comparing at least one of the first real power current demand signal and first reactive power current demand signal to at least one electrical machine current limit signal.
摘要:
A wind turbine generator control system includes relatively fast regulation of voltage near the individual generators with relatively slower overall reactive power regulation at a substation or wind farm level. The setpoint of the relatively fast voltage regulator is adjusted by the relatively slow reactive power regulator. The fast voltage regulation can be at the generator terminals or at a synthesized remote point.
摘要:
A method for determining electric currents for an electrical machine includes generating a first real power current demand signal and a first reactive power current demand signal. The method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing a second real power current demand signal over a second reactive power current demand signal. Alternatively, the method also includes determining at least one of a second real power current demand signal and a second reactive power current demand signal by prioritizing the second reactive power current demand signal over the second real power current demand signal. The method further includes comparing at least one of the first real power current demand signal and first reactive power current demand signal to at least one electrical machine current limit signal.
摘要:
A method for operating an electrical machine includes coupling the electrical machine to an electric power system such that the electric power system is configured to transmit at least one phase of electric power to and from the electrical machine. The method also includes configuring the electrical machine such that the electrical machine remains electrically connected to the electric power system during and subsequent to a voltage amplitude of the electric power system operating outside of a predetermined range for an undetermined period of time.
摘要:
A wind turbine generator control system includes relatively fast regulation of voltage near the individual generators with relatively slower overall reactive power regulation at a substation or wind farm level. The setpoint of the relatively fast voltage regulator is adjusted by the relatively slow reactive power regulator. The fast voltage regulation can be at the generator terminals or at a synthesized remote point.
摘要:
A method of controlling a compressor turbine motor train including: receiving a control signal from a plant process controller; receiving a feedback signal indicative of a state of the electrical grid and adjusting an operational parameter of the compressor turbine motor train to stabilize at least one of a frequency and a voltage of the electrical grid.