Matches 101 - 150 out of 332 < 1 2 3 4 5 6 7 >
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6714427 Current modulation of direct current transmission lines  
A current-modulation method of transmitting high voltage direct current (HVDC) power over a transmission system comprising at least three conductors, wherein each conductor has a nominal thermal...
6703718 Wind turbine controller  
A wind turbine with a permanent magnet alternator that uses a boost mode controller to improve performance at low and high wind speeds. The boost mode controller also allows the permanent magnet...
6697270 Active damper for DC generation systems  
An electrical power system includes a switched reluctance machine/inverter adapted for providing DC power to a load; a voltage controller, which provides a control angle θ C to the switched...
6693409 Control system for a power converter and method of controlling operation of a power converter  
A control system ( 20 ) for a power converter ( 22 ) designed to convert DC power from a source ( 30 ) such as a battery, flywheel or fuel cell into AC power. The control system includes an...
6690143 Power factor correction circuit with resonant snubber  
A power factor correction (PFC) circuit with a resonant snubber. The power factor correction (PFC) circuit has an input part ( 601 ) for receiving an AC voltage and outputting a first DC voltage; a...
6686725 Power supply circuit compensating power factor  
The present invention relates generally to circuit for stabilizing a voltage, and more particularly to a power supply circuit of a power factor compensation type maintaining a PFC output voltage to...
6680602 Reactive power compensator  
When a voltage of a system is stabilized by connecting the system with two types of voltage regulators, i.e., a slow-response tap-changing transformer and a quick-response reactive power regulator,...
6677710 DC output regulator using dual pulse modulation  
In accordance with the teachings of the present invention, an apparatus and method are provided for DC output regulation using dual pulse modulation. A DC output is regulated by reducing the rms...
6674267 Method and a device for compensation of the consumption of reactive power by an industrial load  
An industrial load, preferably an electric arc furnace or a plant for rolling of metallic materials, is supplied from a three-phase electric ac network. A device for compensation of the reactive...
6670793 Dynamic series voltage compensator and method thereof  
A dynamic series voltage compensator ( 10 ) for compensating voltage dips in an ac electric power system is described. The compensator ( 10 ) has a controller ( 11 ) coupled to control a respective...
6664769 Variable amplitude regulator  
Active power factor correction (PFC) circuits are used to minimize unwanted harmonic distortion in applications where AC electrical power is rectified to produce DC power needed for operating...
6657417 Power factor correction with carrier control and input voltage sensing  
A switching power supply which uses carrier control and input voltage sensing. In one aspect, an output voltage is monitored to form a carrier signal. The carrier signal is compared to a signal...
6657322 Control system for active power filters  
An active filter controller for use with both pure and hybrid shunt filters wherein the controller maintains a minimum DC bus voltage required to generate a compensating current on coupling lines...
6653822 Circuit for converting AC voltage into DC voltage  
A circuit for converting AC voltage into DC voltage for one or two devices (Rm, Ra), includes a first part of the current being fed to the input side via a large induction coil (L 50 ) and a first...
6650554 Power factor corrector with efficient ripple attenuator  
Power supply apparatus includes a power factor corrector (PFC) unit, which is adapted to receive an AC voltage from an AC source, and to smooth the AC voltage while adjusting a waveform of an AC...
6650092 System and method for regulating a power system with feedback using current sensing  
A system ( 10 ) regulates current and voltage in a power system by using a correction signal that is modified to compensate for errors associated with manufacturing variations. The correction...
6621252 Control of single-phase power converter in D-Q rotating coordinates  
Imaginary orthogonal circuit state variables are established to enable transformation of real circuit state variables of a single-phase converter or the zero-sequence circuit of a three-phase...
6577108 Voltage regulation of a utility power network  
Power compensation is provided from a power compensation device to a utility power network carrying a nominal voltage. The power compensation device has a steady-state power delivery...
6573690 Feedback controlled power compensation apparatus  
A power conversion apparatus connected to an AC voltage system, including current control circuits provides individual feedback control of an active current and a reactive current. The active...
6570366 Active power factor correction circuit  
An active power factor correction circuit. The circuit comprises a voltage source having a first end and a second end, an inductor having an end coupled to the first end of the voltage source, a...
6473723 Mimic high pass filter in a protective relay  
A mimic filter which can be implemented in analog or digital circuitry, and which removes dc offset or other noise from an input signal using a pseudo-differentiation technique. The input signal is...
6462518 Converter circuit having an inverter for each phase  
A converter circuit is specified for voltage maintenance in an electrical AC supply network ( 1 ), with the electrical AC supply network ( 1 ) having an associated voltage source (UR; US; UT) for...
6459601 Control circuit of power converter  
A control circuit of a power converter selecting an optimal mode for reducing the switching of switching elements. The control circuit includes a current instruction generator for providing current...
6448744 Power factor correction circuit  
A single stage power factor correction circuit is disclosed. The circuit comprises a first comparator for receiving an output voltage and a reference voltage and for providing a control voltage, a...
6433520 Dc power regulator incorporating high power ac to dc converter with controllable dc voltage and method of use  
A high power dc power regulator utilizes a voltage sourced inverter connected on the ac side in series with a large inductance to an ac power system through a coupling transformer. The dc side of...
6411065 Integrated control system and method for controlling mode, synchronization, power factor, and utility outage ride through for micropower generation systems  
An integrated system for comprehensive control of an electric power generation system utilizes state machine control having particularly defined control states and permitted control state...
6411067 Voltage source converters operating either as back-to-back stations or as parallel static var compensators  
A device and a method for controlling the flow of electric power in a transmission line carrying alternating current, in which a first voltage source converter is connected to the transmission line...
6411066 Method to control the flow of active power in a high voltage direct current transmission system and device for the same  
A high voltage direct current transmission system has a first and a second converter station coupled to each other via a direct current link, each converter station with a voltage source converter....
6407536 Power conversion equipment and control device for the power conversion equipment  
A power conversion equipment capable of dealing with an imbalance fault by changing characteristics of a filter for extracting negative-phase-sequence voltage in a steady state and at the time of a...
6392390 Synchronous switching apparatus for use with a multiple phase power system  
A synchronous switching apparatus for detecting a source voltage of each phase to close each phase at an electrical phase angle predetermined for each phase, including switching devices 1 a- 1 c ...
6384580 Communications device for use with electrical source  
One embodiment of this invention includes a source sharing circuit that is coupled to a power machine. Examples of the power machine include micro-turbine generators, gasoline engine powered...
6359422 Surge resistor for protecting active source of variable inductance in a power-factor correction arrangement  
A power-factor correction arrangement incorporates an active inductance source and a passive capacitance source switchably connected in parallel across a source of AC power. The active and passive...
6359423 Method and system for suppressing a voltage fluctuation in a power system  
A system for compensating a voltage fluctuation in a transmission line of a power system is such that a power detection circuit detects a voltage and power flow in the transmission line involving a...
6351397 Protection apparatus and protection method of PWM cycloconverter  
A protection apparatus and a protection method of a PWM cycloconverter wherein when the PWM cycloconverter is shut off, a surge voltage or an overcurrent is not produced on the output side are...
6348778 Method and apparatus for improving the voltage quality of secondary power supply unit  
A method and an apparatus for improving the voltage quality of a secondary power supply unit uses a compensation device with a pulse-controlled power converter which is connected serially to a...
6339231 Gate commutated turn-off thyristor module  
A gate terminal plate ( 1 ) of a GCT thyristor ( 90 ), a connecting substrate ( 70 ) of a driving device and a cathode electrode plate ( 10 ) are interposed between a set of metal rings ( 7 A) and...
6333863 Method to compensate for unbalanced loads in polyphase systems  
The method according to the invention is for compensation currents to be produced which have arbitrary phases and/or arbitrary amplitudes. To this end, a compensation unit (5) is proposed which is...
6329798 Voltage controller for minimizing the utility power provided to a local load site having a local power source  
A load site voltage regulation control system. The load site receives electrical power from a utility over transmission lines. The load site also receives electrical power from a local generator...
6327162 Static series voltage regulator  
A static series voltage regulator (SSVR) for an electric power distribution system protects a load on a feeder branch from voltage dips by boosting voltage under certain conditions. The SSVR...
6262904 Method and device for controlling a static converter powering an electrical source  
The invention concerns a method for controlling a static converter (1) associated with a polyphased electrical source (2) which consists in generating synchronizing times t(i) defined by a periodic...
6255805 Device for electrical source sharing  
An apparatus for electrical source sharing between a power grid, at least one local generator and a local load includes a power circuit, a data port and a controller. The power circuit is capable...
6242895 Controller of adjustable DC voltage for a transformerless reactive series compensator  
A controller for controlling a reactive series compensator serially inserted at compensator terminals into a power transmission line for controlling the line current. The controller includes a...
6225791 Controller for performing a decoupling control of a transformerless reactive series compensator  
A controller for generating a modulation signal m applied to a transformerless reactive series compensator connected serially in a power transmission line. A modulation signal generator generates a...
6191565 Power factor compensation controller  
A power factor compensation controller for use in a switching power supply having a switch, an inductor, and upper and lower reference signals that are proportional to an input voltage to the...
6188205 Power system control apparatus and power system control method  
A desired value of reactive power flow between a to-be-controlled power system and an adjoining power system is determined according to measured values of the reactive power flow and an effective...
6178076 Power-electronic circuit arrangement for compensating for mains system disturbances and mains voltage reductions  
In a power-electronic circuit arrangement for compensating for mains system voltage reductions and mains system disturbances, a second auxiliary voltage source is provided, whose voltage is chosen...
6177781 Power-factor improvement device  
A power-factor improvement device having a voltage stabilizer unit, a current transformer, a voltage and current comparator circuit, an operand microprocessor, a power factor driver, a voltage...
6172488 AC transmission system with reactance compensation  
A series compensation generator SCG is installed in a transmission line that links various substations SS and the transmission capability of the system as a whole can be increased by regulating the...
6144191 Voltage regulator  
A voltage regulator is presented for regulating at least one of voltage, current or power to an electrical load. The regulator includes a transformer series connected between a power source and...
6130524 Method and apparatus for generating and injecting reactive power into an electrical AC power grid system using an inverter  
In the case of a method for feeding reactive power into an AC grid system, in the case of which method at least one line (10) of the grid system has a compensation voltage (U comp ) produced for...
Matches 101 - 150 out of 332 < 1 2 3 4 5 6 7 >