Abstract: A filter device is electrically connected between a power supply and a power converter including a converter unit for rectifying inputs and an inverter unit for inversely converting outputs of the converter unit. The filter device includes a casing; a filter reactor housed inside the casing, for removing a high-frequency component; and a booster reactor housed inside the casing and disposed below the filter reactor, for boosting a voltage of a current having passed through the filter reactor. The booster reactor includes an iron core, a coil wound around the iron core, and a spacer interposed between inner and outer circumferential portions of the coil to form an air passage for passing air introduced into the casing. The booster reactor is stored in the casing so that the air that has passed through the air passage passes through a periphery of the filter reactor disposed immediately above the booster reactor.

Abstract: An improved scheme to filter harmonics and damp resonance for multipulse converter systems using a single characteristic passive filter branch without a plurality of non-characteristic harmonic filters is disclosed. The filter includes a first capacitor, a first inductor and a frequency-dependent resistor block connected in series. The frequency-dependent resistor block includes a second inductor connected in parallel with a circuit which is assembled by a second capacitor in series with a resistor.

Abstract: A system, in one embodiment, includes a voltage fault detection system. The voltage fault detection system may be configured to acquire a reference voltage signal from a power line to determine if a voltage sag condition is present in the power line, determine a correction voltage for correcting the voltage sag condition, use the reference voltage to produce the correction voltage, and apply the correction voltage to the power line.

Abstract: A DC-to-AC conversion apparatus converts a DC input power source to a three-phase AC output power source. The DC-to-AC conversion apparatus includes an input capacitor assembly, a first conversion circuit, a second conversion circuit, and a control circuit. The input capacitor assembly is connected to the DC input power source, and has a neutral point. The neutral point is connected to a first phase sequence of the AC output power source. The first conversion circuit is connected a second phase sequence and a third phase sequence. The second conversion circuit is connected to the first phase sequence, the second phase sequence, and the third phase sequence. The control circuit generates a plurality of control signals to respectively control the first conversion circuit and the second conversion circuit, thus converting the DC input power source into the three-phase AC output power source.

Abstract: A device connectable to a three-phase network, wherein the device includes a capacitor, a secondary coil, a diode and, per phase, a conductor and a circuit, where a secondary-side coil is connected in parallel to the capacitor via the diode, the circuit is configured such that a resistor is located in a conductor, a first capacitor is connected parallel to the resistor, a serial circuit of a first primary-side coil is connected in parallel to the first capacitor, energy transfer occurs from a first primary-side coil to a second primary-side coil and to the secondary-side coil, a second capacitor is connected in parallel to the second primary-side coil, the second capacitor is connected to the source connection of a self-conducting field effect transistor, and the gate connection of the self-conducting field effect transistor is connected to the second capacitor to provide an improved internal power supply for the device.

Abstract: The device comprises a current transformer having a ring-shaped magnetic core (10) internally defining an opening (15) for the arrangement of a power line (2) and a winding wound onto the core (10), the core (10) being split into at least two core segments (A, B) articulated to one another. Both core segments (A, B) are furthermore optimized with regard to surface finish and form factor to allow low attenuation in the low-frequency data signal between 50 kHz and 600 kHz transmitted to the power grid.

Abstract: A method, resonance handling device and computer program product are disclosed for handling resonances in a power transmission system. The resonance handling device can include a resonance frequency determining unit configured to obtain measurements from measurement devices in the power transmission system, apply the measurements in at least one state space model and determine modal resonance frequencies in the system based on the application of the system measurements in the state space model, and an activity determining unit configured to determine the modal activity of at least one of the resonance frequencies.

Abstract: A subsea power distribution system includes a three-phase AC power source; multiple variable frequency drives having inputs and outputs, with their inputs connected to the AC power source; an electric motor connected in series to the output of each variable frequency drive; and a passive harmonic filter system having its input connected, in parallel with the variable frequency drives, to the AC power source. The filter system includes multiple harmonic filters, each harmonic filter tuned to a specific harmonic frequency. Each harmonic filter includes a plurality of sub-filters. Each sub-filter includes a reactor connected in series to a main capacitor and one or more detuning capacitors. Each of the multiple harmonic filters is tuned to a different specific harmonic, and includes sub-filters also tuned to the same respective harmonic, and each sub-filter is sized to equally share the kVAR load of its respective harmonic filter.

Abstract: A heater includes: a power source for supplying power; a heating section for receiving power from the power source and converting the received power into heat energy; an electrical leakage breaker circuit for cutting off a power transfer from the power source to the heating section; and a control section for receiving leaked current information from the electrical leakage breaker circuit and operating the electrical leakage breaker circuit when the leaked current amount exceeds a preset amount or electrical leakage breaker state information is stored, wherein when the power transfer is cut off, the control section stores the electrical leakage breaker state information.

Abstract: A method and system for an uninterruptible power supply (UPS) are provided. The UPS includes a three-phase high power transformer, an active or passive-rectifier configured to generate and regulate a set of DC link voltages, and a set of cascaded inverters configured to generate an AC voltage using the DC link voltages. The UPS also includes a set of bi-directional battery converters configured to charge a bank of backup batteries when power is available from an AC mains source and discharge the bank of backup batteries to generate a three-phase AC voltage when the AC mains source voltage falls outside a predetermined range. The UPS further includes a bypass switch configured to electrically couple the AC mains source directly to a load when the UPS is in a bypass mode of operation and electrically couple the bank of backup batteries to the load through the set of bi-directional battery converters and the transformer.

Abstract: A hand-held test meter for use with an analytical test strip in the determination of an analyte in a bodily fluid sample includes a housing, a clock module disposed in the housing, a micro-controller disposed in the housing, a low-distortion signal generation circuit block (“LDSGCB”) disposed in the housing, and a strip port connector configured to operationally receive the analytical test strip. The LDSGCB includes a signal summation circuit (“SSC”) sub-block, a resistance-capacitance (RC) filter, and a single operational amplifier. The clock module and micro-controller are configured to generate phase-shifted square wave signals and output the phase-shifted square wave signals to the SSC. The SSC is configured to sum the phase-shifted square wave signals to generate a resultant summed-wave signal and output the resultant summed-wave signal to the RC filter. The RC filter is configured to filter harmonics from the resultant summed-wave signal thereby creating a reduced harmonic distortion signal.

Abstract: A transmitter transmits an outbound message signal via the power distribution system. The transmitter includes a spreader for spreading the spectrum of the communications signal before transmitting the outbound message signal. A receiver despreads the spectrum of the received digitized signal and digitally demodulates the received despread signal to generate the message. The transmitted signal is orthogonal to a source of interference on the power distribution system.

Abstract: Methods, devices, and circuits are disclosed for a buck-type AC/DC converter with DC output harmonic control. One example is directed to a AC/DC converter configured to generate a DC output at a target output voltage. The converter is configured to, responsive to an AC input voltage being less than the target output voltage, convert the AC input voltage to a boosted DC output voltage. The converter is further configured to, responsive to the AC input voltage being greater than the target output voltage, convert a first portion of the AC input voltage to a clamped boosted DC output voltage. The converter is further configured to buffer a second portion of the AC input voltage to a buffered DC voltage. The converter is further configured to apply the buffered DC voltage to the clamped boosted DC output voltage.

Abstract: A current-source converter includes high-arm side switching elements and low-arm side switching elements. A voltage between the DC power supply lines is detected as a line voltage of an input line, based on a conduction pattern of the high-arm side switching elements and the low-arm side switching elements.

Abstract: An alternating current input voltage detection circuit comprises: a first voltage waveform detection circuit that detects a voltage waveform of one alternating current input terminal of the diode rectification circuit, based on a reference potential of the device; a second voltage waveform detection circuit that detects a voltage waveform of the other alternating current input terminal of the diode rectification circuit, based on the reference potential of the device, and a voltage waveform generation circuit that: calculates a first detection voltage waveform, which is output from the first voltage waveform detection circuit, and a second detection voltage waveform, which is output from the second voltage waveform detection circuit; generates a voltage waveform signal, in which waveform distortions generated in the first detection voltage waveform and the second detection voltage waveform are eliminated; and outputs the voltage waveform signal as the voltage detection signal.

Abstract: A method is disclosed including but not limited to supplying a voltage waveform from a higher power electrical bus to a lower power electrical bus; sensing on the lower power electrical bus, a deviation from a sinusoidal voltage waveform in the voltage waveform supplied from the higher power electrical bus; generating a correction current to adjust the deviation in the voltage on the lower power bus to a substantially sinusoidal voltage waveform; and filtering the correction current to substantially attenuate the correction current from propagating through the filter from the lower power electrical bus to the higher power electrical bus. A system is disclosed for performing the method.

Abstract: Electric power grid monitoring methods and apparatus are described. According to one aspect, an electric power grid signal processing method includes accessing a plurality of signals which are individually indicative of a characteristic of electromechanical energy within an electric power grid, using the plurality of signals, generating a composite signal, and analyzing the composite signal to provide information regarding an oscillatory mode within the electric power system.

Abstract: A power supply circuit includes a number N, N?2, of parallel connected, cyclically switched electronic converters having outputs connected to a common output terminal; and a controller providing switching pulse signals switching the converters with a switching frequency that is the same for all converters; load circuits connected to the output terminal; a PLC transmitter modulating an output current from the output terminal; and a PLC receiver in each load circuit, the controller switching the converters with interleaved switching pulse signals; the PLC transmitter modulating the output current by switching the controller between at least two modes of operation that differ in phase relations and/or pulse shapes of the switching pulse signals, changing a ripple frequency spectrum of the output current such that a suppression amount of a predetermined frequency component is changed depending upon the mode of operation; and the PLC receiver detects the predetermined frequency component.

Abstract: A passive filter for connection between an AC source and a load, in either three-phases or in a single-phase arrangement. The filter includes, for each phase, a trap circuit having an inductor in series with a capacitor, the trap circuit having at least two terminals. A line reactor is connected between the AC source and the load, the line reactor having at least an input terminal, an output terminal and a tap terminal. A switch selectively connects at least one of the trap circuit terminals to a selected one of the line reactor terminals. The switch is capable of selecting which of the trap circuit terminals to connect to which of the line reactor terminals on the basis of a level of voltage distortion being experienced by the AC source, or on the basis of a calculated level of background voltage total harmonic distortion.

Abstract: A network signal coupling and EMI protection circuit assembly includes a processing circuit installed in a circuit board and coupled between a voltage-mode network-on-chip at the circuit board and a network connector and drivable by a driving voltage outputted by the voltage-mode network-on-chip to process network signals. The processing circuit includes opposing first connection end and second connection end, two-wire channels electrically connected between the first connection end and the second connection end, a coupling module and an EMI protection module installed in each two-wire channel for coupling network signals and removing noises.

Abstract: A network signal coupling and EMI protection circuit assembly includes a processing circuit installed in a circuit board and coupled between a voltage-mode network-on-chip at the circuit board and a network connector and drivable by a driving voltage from the voltage-mode network-on-chip to process network signals. The processing circuit includes opposing first connection end and second connection end, two-wire channels electrically connected between the first connection end and the second connection end, a coupling module and an EMI protection module installed in each two-wire channel for coupling network signals and removing noises.

Abstract: Embodiments relate to systems and methods for tuning the control of a shunt active power filter over a variable frequency. In aspects, a shunt active power filter is provided to filter current harmonics from the output delivered to a dc load via a rectifier. The shunt active power filter control can be configured as a set of resonant regulators connected in a parallel configuration. Each of the resonant regulators can be tuned to dampen or eliminate a particular harmonic, such as the 5th, 7th, 11th, 13th, 17th or 19th harmonics. The shunt active power filter can be configured to target those or other harmonics over a range of source voltage frequencies, such as 360-800 Hz. The harmonics can be tuned over that or other source frequency ranges by determining the root locus poles of the filter as a function of feedback loop gain.

Abstract: Described is a method for operating a converter for a system for generating electrical energy. In an embodiment of the method, the output voltage of the converter is converted to a d, q coordinate system, wherein the d, q coordinate system is assigned to the frequency of the voltage for the energy supply grid. A desired value is furthermore specified in the d, q coordinate system, several momentary or future values are determined from the output voltage in the d, q coordinate system for different switch positions of the converter, deviations between the desired value and the momentary or future values are determined in the d, q coordinate system, and the converter is switched to one of the switch positions in dependence on these deviations.

Abstract: A module assembly for the application-specific construction of power factor correction, filter, and absorption circuit systems in selectively non-choked, choked, protective or thyristor-connected design, comprising a busbar system, fuse holders, switch components, at least one choke, and power capacitors. A first module unit has a first section for receiving busbars, fuse holders, fuses, a busbar cover as protection against accidental contact with the busbar, and a second, trough-like section for receiving switch components that can be mechanically fixed and electrically contacted. A second module unit is designed to receive switchable capacitor winding blocks, enclosing the at least one winding block, insulating the same. The first and the second module unit each have a base region, wherein mechanical and/or electrical connections are led via apertures in the base regions, such that either a back-to-back assembly with direct docking of the first and second module units can be affected.

Abstract: A control unit for an active filter for reducing resonance in an electric system is provided. The electric system comprises a power source distributing an alternating current to an AC conductor connected to a power consuming unit for distributing the AC to the power consuming unit. The active filter comprises a DC power source and a DC conductor connecting the DC power source to the AC conductor. The control unit comprises: a voltage measurement unit adapter to create a voltage signal on the basis of a measured voltage; a computing unit adapted to compute, using a biquadratic filter, a first compensating current on the basis of the voltage signal for reducing resonance in the electric system; and a switching system placed between the DC power source and the DC conductor for creating the calculated first compensating current.

Abstract: A method of damping power system oscillations includes obtaining an AC measurement signal from a power system location and determining oscillation frequency values in the AC measurement signal. A plurality of single signal components are extracted from the AC measurement signal by subtracting a plurality of processed measurement signals from the AC measurement signal and a damping signal is generated based on the plurality of single signal components. Each of the plurality of processed measurement signals are generated by time delaying the AC measurement signal with a time delay associated with each of the oscillation frequency values other than the oscillation frequency value of the single signal component to be extracted.

Abstract: A control apparatus for a power quality device comprises: a power quality analysis module, for sampling a power supply network to obtain a power quality information, and performing an analysis and computing on the sampling, so as to output an instruction information; N tracking control modules, for receiving respectively the instruction information and tracking the instruction information, so as to output N PWM control signals having a same frequency and constant phase shift therebetween, where N is a positive integer and N?2, thereby to control the power quality device; wherein the power quality analysis module and the N tracking control modules are operated based on a synchronized signal.

Abstract: A subsea power distribution system includes a three-phase AC power source; multiple variable frequency drives having inputs and outputs, with their inputs connected to the AC power source; an electric motor connected in series to the output of each variable frequency drive; and a passive harmonic filter system having its input connected, in parallel with the variable frequency drives, to the AC power source. The filter system includes multiple harmonic filters, each harmonic filter tuned to a specific harmonic frequency. Each harmonic filter includes a plurality of sub-filters. Each sub-filter includes a reactor connected in series to a main capacitor and one or more detuning capacitors. Each of the multiple harmonic filters is tuned to a different specific harmonic, and includes sub-filters also tuned to the same respective harmonic, and each sub-filter is sized to equally share the kVAR load of its respective harmonic filter.

Abstract: A low-power high-speed asynchronous inductive-coupling transmission and reception technology is provided, in which a current signal of a single pulse is made to flow through a transmitting coil, and a voltage signal of a double pulse induced in an inductively-coupled receiving coil can be received asynchronously. A transmitting circuit for performing non-contact proximity communication adopts a configuration in which current flows through a first coil in a first direction for each change of a logical value of transmit data. A receiving circuit connected to a second coil coupled inductively to the first coil employs a comparator which determines an induced voltage of a double pulse induced in the second coil by current in the first direction and outputs a unipolar single pulse signal. Whenever the single pulse signal outputted by the comparator is inputted, the receiving circuit inverts the output in a sequential circuit and reproduces receive data.

Abstract: A smart link in a power delivery system includes an insulator, which electrically isolates a power line, and a switchable conductance placed in parallel with the insulator. The switchable conductance includes switchgear for sourcing, sinking, and/or dispatching real and/or reactive power on the power line to dynamically in response to dynamic loading, transient voltages and/or currents, and phase conditions or other conditions on the power line.

Abstract: An apparatus for removing harmonic noise from a power transmission line transmitting electricity at a primary frequency includes a filter and a controller coupled to the sensor and to an actuator-generator. The filter separates electricity at a harmonic of a primary frequency from the electrical signal transmitted by the power transmission line. The controller is configured to modulate consumption of electricity from the power transmission line. The consumption is controlled by electrical actuation of the actuator-generator, such that the electrical actuation of the actuator-generator causes consumption of electricity from the power transmission line at a harmonic of the primary frequency. The actuator-generator is coupled to an elastically deformable component, such that electrical actuation of the actuator-generator generates tension in the elastically deformable component.

Abstract: A system and a method for compensating harmonic components or a reactive power of an electrical network. The system comprises a measurement unit (1) configured to measure an electrical quantity to be compensated, a control unit (2) configured to determine harmonics contents or a reactive power need of the measured electrical quantity to be compensated as well as to determine, as relative values, desired values corresponding with the harmonics to be compensated or the reactive power to be compensated, one or more compensation units (5, 6) configured, responsive to the desired values provided by the control unit (2), to generate harmonic components or a reactive current according to the desired values given as relative values, and a communications connection (3) configured to communicate the desired values determined by the control unit (2) to the compensation units (5, 6).

Abstract: A generator system includes an AC generator having one or more phases, a transformer having the same number of phases as the generator, and for each phase of the AC generator, a capacitive element having a first terminal electrically connected to an output winding of the AC generator and a second terminal electrically connected to a primary winding of a respective phase of the transformer. A method of operating a generator system includes conveying current between an output winding of each phase of an AC generator and a primary winding of a respective phase of a transformer via a respective series-connected capacitive element having a first terminal electrically connected to the output winding and a second terminal electrically connected to the primary winding.

Abstract: A power conversion system for providing power to an electrical grid is described. The power conversion system includes a power converter coupled to a power source and the electrical grid. The power conversion system also includes a converter controller coupled to the power converter and configured to control operation of the power converter to actively cancel harmonic current received at the power converter from the electrical grid.

Abstract: An apparatus for removing harmonic noise from a power transmission line transmitting electricity at a primary frequency includes a filter and a controller coupled to the sensor and to an actuator-generator. The filter separates electricity at a harmonic of a primary frequency from the electrical signal transmitted by the power transmission line. The controller is configured to modulate consumption of electricity from the power transmission line. The consumption is controlled by electrical actuation of the actuator-generator, such that the electrical actuation of the actuator-generator causes consumption of electricity from the power transmission line at a harmonic of the primary frequency. The actuator-generator is coupled to an elastically deformable component, such that electrical actuation of the actuator-generator generates tension in the elastically deformable component.

Abstract: In some embodiments, a method is disclosed that includes measuring a waveform of a power source side voltage of a circuit breaker; measuring a waveform of a transmission line side voltage of the circuit breaker; calculating a waveform of a voltage between contacts of the circuit breaker that is a difference between the waveform of the power source side voltage and the waveform of the transmission line side voltage; calculating a waveform of an absolute value of the waveform of the voltage between contacts; extracting a waveform of a component in a frequency band which is lower than a frequency of the power source and higher than a frequency of a DC component from the waveform of the absolute value; detecting a cycle of the extracted waveform; and closing the circuit breaker based on the cycle.

Abstract: A method, device and computer program product for providing improved control of power or voltage oscillation damping in a power transmission system. The device includes a magnitude obtaining element configured to obtain an instantaneous magnitude of a signal representing a deviating oscillation in at least one element of the power transmission system, a slope investigating element configured to determine the rate of change of the signal, and a first processing block including an integrating element configured to integrate the instantaneous magnitudes with an integrating factor that is based on the determined rate of change. The first processing block is further configured to form a phase compensation angle based on the integrated instantaneous magnitude for use in a damping control signal generating unit in order to provide power or voltage oscillation damping of the system.

Abstract: An uninterruptible power supply (UPS) system that includes a multiphase AC output configured to be coupled to a load, an inverter having an output coupled to the AC output and a control circuit operatively associated with the inverter and configured to cause the inverter to compensate for a phase imbalance of a load coupled to the AC output while power is being delivered to the load from an AC power source independently of the inverter.

Abstract: A first SVC is connected to a first bus. A first SVC control unit controls the first SVC. A first fluctuation-component-voltage generating unit includes a voltage reference circuit that outputs a voltage reference value. A second SVC is connected to a second bus. A second SVC control unit controls the second SVC. A second fluctuation-component-voltage generating unit includes a first-order-lag control block with limiter that generates a comparative voltage that follows a bus voltage of the second bus with a predetermined time lag characteristic and is limited within a predetermined range. An impedance value XS1 of slope reactance of the first SVC is set smaller than impedance value XS2 of slope reactance of the second SVC.

Abstract: An active switching ripple filter system removes ripple currents from a power signal and has a main inverter and an active switching ripple filter inverter whose outputs are combined to form an output power signal.

Abstract: System, method, and computer program product for dampening oscillations of the electrical power on a power grid. The system includes a wind park with multiple wind turbines. Each wind turbine includes a rotor, a generator operatively coupled with the rotor for generating electrical power, and an inverter coupling the generator with the power grid to output the electrical power to the power grid. A controller is configured to generate a first control signal to cause the inverter of the first wind turbine to modulate the electrical power output by the first wind turbine for dampening oscillations of one frequency in electrical power on the power grid and to generate a second control signal to cause the inverter of the second wind turbine to modulate the electrical power output by the second wind turbine for dampening oscillations of a different frequency in the electrical power on the power grid.

Abstract: An input circuit includes an interface structured to output a logic signal from an alternating current signal of a pair of elongated conductors. A load is switchable to the elongated conductors. A processor outputs a control signal to switch the load to the elongated conductors asynchronously with respect to the alternating current signal for a first predetermined time, inputs the logic signal, determines if the input logic signal is active a plurality of times during the first predetermined time and responsively sets a first state of the alternating current signal, and, otherwise, sets an opposite second state of the alternating current signal, and delays for a second predetermined time, which is longer than the first predetermined time, for the opposite second state before repeating the output, and, otherwise, delays for a third predetermined time, which is longer than the second predetermined time, for the first state before repeating the output.

Abstract: An apparatus for removing harmonic noise from a power transmission line transmitting electricity at a primary frequency includes a filter and a controller coupled to the sensor and to an actuator-generator. The filter separates electricity at a harmonic of a primary frequency from the electrical signal transmitted by the power transmission line. The controller is configured to modulate consumption of electricity from the power transmission line. The consumption is controlled by electrical actuation of the actuator-generator, such that the electrical actuation of the actuator-generator causes consumption of electricity from the power transmission line at a harmonic of the primary frequency. The actuator-generator is coupled to an elastically deformable component, such that electrical actuation of the actuator-generator generates tension in the elastically deformable component.

Abstract: A power delivery system is disclosed for an isolated measurement system in which a power transmitter and power receiver are provided at powered and unpowered sides of an isolation barrier, respectively. The power transmitter and power receiver may be coupled by an isolator. The power transmitter may deliver power to the power receiver to power components on the unpowered side of the isolation barrier. The system may include a controller provided in the powered side to generate a clock signal defining timing of a predetermined operation of the measurement system and to generate a disabling signal to the power transmitter controller synchronously with the timing of the predetermined operation.

Abstract: A device for converting a DC voltage into an AC voltage and vice versa comprises at least one phase leg with a first voltage source and a first inductor connected in series between a first DC terminal and a first AC terminal and with a second inductor and a second voltage source connected in series between the first AC terminal and a second DC terminal, where each of the voltage sources comprises at least a first and a second submodule in series-connection, each submodule comprising at least one power electronic switch connected in parallel with at least one capacitor. In the device, a passive electronic filter is arranged between the first and the second inductor as well as the first AC terminal for reducing harmonics in a circulating current.

Abstract: A one-phase static var compensator apparatus includes a compensator string consisting of a first static var compensator connected serially to a thyristor valve. The compensator string is arranged to be connected on its first end to one phase of a transmission grid of a rated voltage exceeding 69 kV. Moreover, the thyristor valve includes a plurality of thyristors connected serially and the compensator string is arranged to be directly connected to the transmission grid. A corresponding three phase apparatus is also presented.

Abstract: A method and controller are provided for the compensation of time delays in remote feedback signals in power system control. The method includes converting the time delay into a phase shift and calculating four compensation angles from the phase shift. The optimal compensation angle is determined and applied to the remote feedback signals. A technique of equipping a controller with a global clock is also disclosed.

Abstract: A method is disclosed including but not limited to supplying a voltage waveform from a higher power electrical bus to a lower power electrical bus; sensing on the lower power electrical bus, a deviation from a sinusoidal voltage waveform in the voltage waveform supplied from the higher power electrical bus; generating a correction current to adjust the deviation in the voltage on the lower power bus to a substantially sinusoidal voltage waveform; and filtering the correction current to substantially attenuate the correction current from propagating through the filter from the lower power electrical bus to the higher power electrical bus. A system is disclosed for performing the method.

Abstract: A USB connector, a PCB connected to the USB connector, and a USB device are provided. The USB connector includes a metal surface, and on the metal surface, a solid metal part is set at a location corresponding to a spring of a socket, so that the spring contacts the solid metal part after the USB connector is inserted into the socket to reduce electromagnetic interference. The USB connector may include an in-line weld leg; a metal enclosure located at the same side as the in-line weld leg fully contacts a PCB when the USB connector is connected to the PCB; and contact surfaces on the USB connector that contact the PCB are metal surfaces. The PCB includes a suppression circuit configured to suppress harmonic waves in USB data transmission.

Abstract: Methods and apparatus for power factor correction include selectively coupling bit reactive loads with a load having dynamic reactive properties to dynamically correct a power factor. Methods and apparatus for reducing distortion in a power delivery system include a means for determining distortion in a power line, forming a corrective signal according to the distortion and selectively sinking and sourcing current to the power line according to the corrective signal.