Abstract: Methods of powering a radio that is mounted on a tower of a cellular base station are provided in which a direct current (“DC”) power signal is provided to the radio over a power cable and a voltage level of the output of the power supply is adjusted so as to provide a substantially constant voltage at a first end of the power cable that is remote from the power supply. Related cellular base stations and programmable power supplies are also provided.

Abstract: A converter that makes it possible to selectively switch between various converter architectures that are capable of supplying different output voltages on the basis of one and the same input voltage. The various architectures share at least some electronic components with one another, thereby decreasing the production cost of the converter according to the invention. The converter is particularly advantageous for lighting modules for motor vehicles, in which there are substantial space constraints but in which wide output-voltage ranges are required to be able to supply a varied and substantial number of electroluminescent light sources (LEDs) with power.

Abstract: A display device is disclosed. The display device of present invention comprises a display unit providing an image; a control unit placed spaced apart from the display unit, the control unit providing the display unit with a electric power and a signal; a cable electrically connect the display unit and the control unit, the cable carrying the electric power and the signal; and a controller configured to control a property of the electric power in accordance with a length of the cable.

Abstract: This invention relates to switching amplifiers and switching power converters with bipolar outputs. A new circuit configuration is disclosed which is neither ‘single ended’ nor ‘bridged’. This introduces a new category of amplifiers and power converters, which are ‘spanning’. Also disclosed are new circuit topologies and new switching sequence strategies for such amplifiers and converters. These unlock improvements in power efficiency, space efficiency and cost efficiency. The improvements can be obtained across a wide range of signal amplitudes, with load circuits which may be resistive, partly reactive, or wholly reactive.

Abstract: [Object] To provide a DC power transmission device capable of supplying properly a previously agreed amount of power between the power transmission side and the power reception side when customers supply power to each other. [Solution] Provided is the DC power transmission device including: a power supply request acquisition unit configured to acquire a power supply request from a DC power reception device, the DC power reception device being configured to receive DC power from a DC bus line; and a transmission power decision unit configured to decide a parameter of DC power to be outputted to the DC power reception device via the DC bus line based on the power supply request and a characteristic of a power storage device, the power storage device being configured to supply DC power to the DC bus line. The parameter includes power transmission time of DC power that reflects a power transmission loss occurred until DC power reaches the DC power reception device.

Abstract: A power conversion device includes a potential variation suppression portion having first and second ground capacitors and a reactor, for suppressing a potential variations at an A point at which switching elements and are connected together and at a B point in a bidirectional switch. The potential variation suppression portion suppresses potential variation at the A point by cancelling a first leakage current, which flows due to the potential variation at the A point at the positive and negative polarities of an alternating current voltage, with a first compensating current flowing via the reactor and ground capacitor, and suppresses the potential variation at the B point by cancelling a second leakage current, which flows due to the potential variation at the B point at the negative polarity of the alternating current voltage, with a second compensating current flowing via the reactor, a switch, and the second ground capacitor.

Abstract: A series injection device includes a power splitter coupled to two or more lines of an AC power system. The power splitter includes a coupling transformer for each phase of a single phase or polyphase AC circuit that includes the two or more lines. Each of the coupling transformers couples one of the phases of the two or more lines. The power splitter is configured to inject a first voltage of a first polarity into one or more of the two or more lines and inject a second voltage of a second polarity opposite the first polarity into at least one of the two or more lines via the same coupling transformers used to inject the first voltage. The first and the second voltages are controllable, and may or may not be independently variable.

Abstract: In certain embodiments, a compound power converter passes the majority of power from input to output through only a single stage of power conversion. At least one embodiment includes a main converter with an auxiliary output. The auxiliary output energizes an energy storage element that provides input power for a supplemental converter capable of supplying the main output. The supplemental converter improves regulation and can provide holdover power for Power Factor Correction (PFC) or Uninterruptible Power Supply (UPS) operation. In certain embodiments, the power converter has at least one multi-functional inductor that supports both main regulation and supplemental regulation in a time-multiplexed manner such that, during main regulation, input energy is transferred from the input node to the output node via the multi-functional inductor, and, during supplemental regulation, the stored energy is transferred from the at least one energy storage element to the output node via the multi-functional inductor.

Abstract: Systems and devices that provide a shared detuning, damping, or filtering element to one or more capacitors. A number of circuit branches are coupled in parallel to each other between a first coupling point and a second coupling point. A subcircuit is coupled between the second coupling point and a third coupling point. Each branch includes at least one capacitor that provides reactive power to power systems while the subcircuit is configured to provide detuning, damping, or filtering to the multiple branches.

Abstract: A fault current limiter of the type having at least one elongated core biased magnetically towards saturation by means of a surrounding magnetic field, and an AC coil surrounding the core, the fault current limiter including: an elongated core having a variable cross section along the axis of the core in the vicinity of the AC coil, providing increased saturation of the core and enhanced fault current limiting for a lower DC bias.

Abstract: An AC/DC converter includes a rectifier circuit and a power factor correction circuit. An input port of the rectifier circuit receives an alternate current. The power factor correction circuit includes a first inductor, a second inductor, a first capacitor, a second capacitor, a first diode and a second diode. An end of the first inductor electrically connects to a positive pole of an output port of the rectifier circuit, and the other end electrically connects to a ground terminal of the output port through two parallel series routes which are bridged by the first diode. Wherein a series route contains the first capacitor and the second diode, and the other series route contains the second inductor and the second capacitor. The second capacitor is provided for parallel connecting with a loading. In this way, the input current could be controlled to increase the power factor effectively.

Abstract: There are provided a power factor correction circuit capable of transferring extra power to a ground before performing switching for a power factor correction to thereby reduce a switching loss generated in switching for a power factor correction, and a power supply device and a motor driving device having the same. The power factor correction circuit includes: a main switch switching input power to adjust a phase difference between a current and a voltage of the input power; and an auxiliary switch switched on before the main switch is switched on, to thereby form a transmission path for extra power of the main switch.

Abstract: The invention provides a power converter and method for controlling same, comprising a plurality of switch elements, an inductive reactor, and at least two ports for the movement of electrical energy. Any energy-moving port may be made unipolar, bidirectional, bipolar, or bidirectionally bipolar. Ports may be equipped with sensing circuitry to allow the converter output to be controlled responsively to an input signal. The invention may be configured to be used in many ways, for example, as a power-supply, as an amplifier, or as a frequency converter. The invention may comprise energy predictive calculating means to obtain excellent transient response to line and load variations. The invention may also include a switch to create a low impedance path around the inductor to allow current to recirculate through the inductor when it is not needed at any of the ports.

Abstract: First windings of a first common mode transformer and second windings of a second common mode transformer are connected in series via connection lines. The windings are connected to an AC power supply via connection lines. The first windings are connected to a three-phase motor via connection lines, a converter, and an inverter. High-frequency leakage currents flowing in the connection lines are detected as a common mode voltage by a winding for common mode voltage detection. An output voltage is inputted via a filter to a voltage amplifier unit that amplifies the output voltage, and the amplified voltage is applied to a winding via a capacitor in substantially a same direction as a direction of the common mode voltage. As a result, leakage currents are reduced by induced voltages on the windings.

Abstract: In the case of a power supply device (2) for an electric circuit (3), an energy source (4) and an electric filter (7) are provided for the reliable and low-emission supply of energy to the electric circuit (3), wherein the energy source (4) and the electric filter (7) interact in such a way that the power supply device (2) has, at a filter output (9), a voltage source characteristic in a first frequency range and a current source characteristic in a second frequency range, which has a higher frequency than the first frequency range.

Abstract: A reactor arrangement for alternating electrical currents includes, for each alternating electrical current, different coils (105, 107, 105a, 107a) for positive and negative half-cycles of that alternating electrical current. The negative and positive half-cycles of the alternating electrical current are directed to the different coils with the aid of unidirectional electrical components (106, 108, 106a, 108a) such as, for example, diodes. All coils are arranged to magnetize a common magnetic core element (104) in a same direction. Therefore, from the viewpoint of the magnetization of the magnetic core element, the flowing directions of the alternating electrical currents are not significant. Hence, the common-mode inductance of the reactor arrangement has substantially a same value as the differential-mode inductance.

Abstract: A reactor arrangement for alternating electrical current includes different coils (105, 107) for positive and negative half-cycles of the alternating electrical current. The negative and positive half-cycles of the alternating electrical current are directed to the different coils with the aid of unidirectional electrical components (106, 108) such as, for example, diodes. The both coils are arranged to magnetize a common magnetic core element (104) in a same direction. The reactor arrangement further includes at least one permanent magnet (109) that generates, into the magnetic core element, a biasing magnetic flux component having an opposite direction than that of magnetic flux components generated with the coils. Therefore, the biasing magnetic flux component generated with the permanent magnet relieves magnetic saturation of the magnetic core element. Hence, the size and the weight of the magnetic core element can be reduced.

Abstract: The present invention is a spike converter providing a special mode of operation of a low power fly-back converter in a very narrow duty cycle range in particular. This spike operation minimizes the size of the required reactive components such as that of the power transformer and output capacitance. The present invention automatically achieves low idle power consumption due to the nature of the feedback under fixed, narrow duty cycle or spike operation. The spike operation is defined by the lower limit of the on time of the switching element being generated by the sum of the propagation delays of a current sense comparator and an off time pulse generating comparator.

Abstract: A power-conversion regulator comprising an inductive reactor, an output filter reactor, and a switch for admitting energy to the inductive reactor, additionally comprises computation circuitry responsive to the flux in the inductive reactor, to a reference signal, to an output voltage, and sometimes to an output load current, for computing the quantity of energy that must be supplied to a load and to the output filter reactor to regulate the output voltage or current to a desired relationship with the reference signal during each chopping waveform cycle driving the switch. As the inductive reactor is charged from an input energy source, the computation circuitry predicts whether the energy in the inductive reactor has become adequate for the regulation.

Abstract: An AC-DC converter includes a rectifier DB for rectifying an alternating current supplied from an alternating power source AC, a power factor controller 11a connected to an output side of the rectifier DB to improve a power factor and also output either a power or a current limited to a predetermined value, a DC-DC converter 12 that converts a voltage outputted from the power factor controller 11 to another voltage, a capacitor EDLC for storing an energy and a two-way converter 13 having one input/output terminals connected to the output side of the power factor controller 11a and the other input/output terminals connected to the capacitor to carry out a two-way power conversion.

Abstract: A compensation circuitry for providing reactive power to a network includes an inductance means and a capacitor means associated with switching appliances and with a controlling mechanism. The compensation circuitry is used for delivering reactive power compensation to electrical networks of either low or high voltage. The inductance means and the capacitor means are connected serially, thereby bringing the circuitry to a virtual gain selected from a group consisting of virtual inductance gain (VIG) or virtual capacitance gain (VCG), and wherein the virtual gain selected from the group is above the absolute value of 1.5.

Abstract: A control apparatus of a DC-DC converter includes a reactor and a switching element, repeats an accumulation and a discharge of energy of the reactor by a switching operation of the switching element, and converts a direct-current input voltage to acquire a direct-current output voltage. The control apparatus includes: a current value acquiring unit that acquires current values of the reactor in a current rising section and a current descending section of a current waveform of the reactor at a time interval of a half of a switching period of the switching element; and a center value estimating unit that estimates a center value of a current of the reactor based on the current values acquired in the current rising section and the current descending section.

Abstract: The invention provides a power converter and method for controlling same, comprising a plurality of switch elements, an inductive reactor, and at least two ports for the movement of electrical energy. Any energy-moving port may be made unipolar, bidirectional, bipolar, or bidirectionally bipolar. Ports may be equipped with sensing circuitry to allow the converter output to be controlled responsively to an input signal. The invention may be configured to be used in many ways, for example, as a power-supply, as an amplifier, or as a frequency converter. The invention may comprise energy predictive calculating means to obtain excellent transient response to line and load variations. The invention may also include a switch to create a low impedance path around the inductor to allow current to recirculate through the inductor when it is not needed at any of the ports.

Abstract: An induction regulator for controlling the voltage amplitude and/or phase angle of a polyphase electric transmission network connected between the primary side and the secondary side of the transmission network. The rotor is fixed in relation to the stator and the volume between stator and rotor includes a magnetic volume with a region including a controllable magnetic flux region of solid material that has a relative permeability that is controllable by changing its temperature.

Abstract: An AC-DC converter includes a rectifier DB for rectifying an alternating current supplied from an alternating power source AC, a power factor controller 11 connected to an output side of the rectifier DB to improve a power factor, a DC-DC converter 12 that converts a voltage outputted from the power factor controller 11 to another voltage and also outputs either a power or a current limited to a predetermined value, a capacitor for storing an energy and a two-way converter 13 having one input/output terminals connected to output terminals of the DC-DC converter 12 and the other input/output terminals connected to the capacitor to carry out a two-way power conversion.

Abstract: A power-conversion regulator comprising an inductive reactor, an output filter reactor, and a switch for admitting energy to the inductive reactor, additionally comprises computation circuitry responsive to the flux in the inductive reactor, to a reference signal, to an output voltage, and sometimes to an output load current, for computing the quantity of energy that must be supplied to a load and to the output filter reactor to regulate the output voltage or current to a desired relationship with the reference signal during each chopping waveform cycle driving the switch. As the inductive reactor is charged from an input energy source, the computation circuitry predicts whether the energy in the inductive reactor has become adequate for the regulation.

Abstract: Provided are a method and apparatus for improving the power factor of an input power. The apparatus includes an input unit receiving the input power, a power factor correction unit correcting the power factor of the input power applied to the input unit, and a saturation prevention unit controlling the power factor correction unit such that the corrected power does not exceed a set power limit.

Abstract: Disclosed a multi-output type DC/DC converter including: a reactor connected to a direct-current power supply; a first switching circuit composed of switches to apply a current to the reactor; a second switching circuit composed of switches to switch an output from the reactor to any one of output terminals; output voltage detection sections to detect voltages of the output terminals; comparison circuits to compare outputs with a waveform signal of a predetermined frequency; and an output selection circuit to receive inputs form comparison circuits, and to select an output of a comparison circuit, the output having the earliest rise or the earliest fall, so as to generate a control signal pertaining to on and off of the first and/or second switching circuit, wherein a current generated by a discharge of energy accumulated in the reactor is output to any one of the terminals in accordance with the control signal.

Abstract: A method for designing a power factor controller apparatus for a power distribution network comprising the phases of: configuring, in a predefined computerised support, an interactive computerised environment (2) dedicated to the management of data and/or programming commands (reference 1); and acquiring, in said interactive computerised environment, data related to said power factor controller apparatus (reference 3); and acquiring and/or calculating, in said interactive computerised environment, data related to the power distribution network (reference 4) wherein said power factor controller apparatus is installed; and based on said phase e), calculating, in said interactive computerised environment, the optimal chasing of a power factor target for said power factor controller apparatus (reference 5).

Abstract: A power delivery apparatus and method which calibrates a voltage delivered from a central unit to a remote unit to compensate for losses in the supply lines between the central unit and remote unit is disclosed. The impedance of the supply lines is determined utilizing a reference voltage conducted by a calibration line, a sweep tone transmitted down the supply line, or a time domain reflectometer technique. Based upon the determined impedance of the supply lines, the voltage delivered from the central unit can be calibrated accordingly. Alternatively, the impedance can be determined and the voltage calibrated based on the measured input voltage to the remote unit or the measured power level of a signal transmitted from the remote unit.

Abstract: An apparatus for providing an electrically controllable inductor which uses a first and a second magnetic core (20, 24) spaced apart from one another. A DC bias coil (22) is wound on the first magnetic core (20). An inductor coil (26) is wound on both the first magnetic core (20) and the second magnetic core (24). The inductance seen at terminal connections (80, 82) of the inductor coil (26) is variable in dependence upon a magnitude of a flow of direct current through the DC bias coil (22). In one embodiment of the inductor, the first and the second magnetic core (20, 24) are each formed using a pair of U-shaped core segments (30, 32, 60, 62) located adjacent to one another. In this embodiment, the first and second magnetic core (20, 24) are located in an opposing relation to one another, with the DC bias coil (22) wound on inner legs (64, 72) of the first magnetic core (20) and the inductor coil (26) wound on inner legs (64, 72, 34, 44) of both the first and the second magnetic core (20, 24).

Abstract: An apparatus for providing an electrically controllable inductor uses a first and a second magnetic core (20, 24) spaced apart from one another. A DC bias coil (22) is wound on the first magnetic core (20). An inductor coil (26) is wound on both the first magnetic core (20) and the second magnetic core (24). The inductance seen at terminal connections (80, 82) of the inductor coil (26) is variable in dependence upon a magnitude of a flow of direct current through the DC bias coil (22). In one embodiment of the inductor, the first and the second magnetic core (20, 24) are each formed using a pair of U-shaped core segments (30, 32, 60, 62) located adjacent to one another. In this embodiment, the first and second magnetic core (20, 24) are located in an opposing relation to one another, with the DC bias coil (22) wound on inner legs (64, 72) of the first magnetic core (20) and the inductor coil (26) wound on inner legs (64, 72, 34, 44) of both the first and the second magnetic core (20, 24).

Abstract: The present invention provides means to instantaneously optimize reactive kva for an a.c. power system containing both linear and non-linear reactive loads. The preferred means utilizes a reflux transformer which is tuned for maximum energy transfer between primary and secondary windings. Each secondary winding is connected in series with a variable inductor and a fixed capacitive means, so as to continuously reflect variable reactive kva to the power system via the primary and secondary windings. The reactive kva requirements of the power system can thus be continuously optimized without destructive voltage transients associated with switching graduated units of fixed capacitive compensation or incurring the risk of conducting series resonant currents associated with non-linear loads.

Abstract: A process for parallel control of tap transformers in which individual voltage regulators of parallel operating transformers are connected to a single parallel processor by serial data lines and the measured values of the voltage and current amplitudes and the phase angles are transmitted by the voltage regulators to the parallel processor, an interference variable for each voltage regulator is calculated in the parallel processor from the partial load current and the circulating reactive current and is transmitted with the partial load current by the serial data lines to the voltage regulators, and each voltage regulator then calculates an LDC variable for load drop compensation, by summing the measured voltage, the received interference variable and the LDC variable provides a controlled variable or voltage value which constitutes the new set point with respect to which the voltage regulator then controls the transformer to which it is assigned.

Abstract: There is disclosed herein a driver system for an ultrasonic probe for allowing a user to have proportional control of the power dissipated in the probe in accordance with the position of power dissipation controls operable by the user and for automatically tuning upon user request such that the driving frequency is equal to the mechanical resonant frequency of said probe and such that the reactive component of the load impedance represented by said probe is tuned out. The system uses a tunable inductor in series with the piezoelectric crystal excitation transducer in the probe which has a flux modulation coil. The bias current through this flux modulation coil is controlled by the system. It is controlled such that the inductance of the tunable inductor cancels out the capacitive reactance of the load impedance presented by the probe when the probe is being driven by a driving signal which matches the mechanical resonance frequency of the probe.

Abstract: An automatic power factor control apparatus for an inductive load such as an AC induction motor includes a circuit for producing a signal varying in accordance with the load power factor, which is applied to control the duty cycle with which switching elements are alternately set in the conducting and non-conducting states by high frequency switching operation. A level of voltage applied to the control winding of a saturable reactor connected in series with the load is controlled by the switching elements, and the saturable reactor thereby continuously controls the input voltage and load current of the inductive load in accordance with the power factor.

Abstract: In a hybrid switched-capacitor controlled-reactor static VAR compensator including a fixed-capacitor, hysteresis on switching-OFF a switchable capacitor of the capacitance bank is performed with a minimal fixed-hysteresis at the entrance of the standby region and with a temporary and variable-hysteresis in relation to any operating point in the standby region whenever maintaining the capacitor OFF is required. Since the fixed-hysteresis operates most often to prevent switching-OFF of the capacitor while the variable-hysteresis will operate less often, the losses at standby are minimized during thyristor-switched capacitor operation through most of this.

Abstract: A method for attenuating at least one unwanted harmonic, particularly the second harmonic, with respect to the system frequency in a multi-phase alternating current system, wherein an additional stabilizing circuit is installed into a conventional current/voltage controller including a current/voltage controller and a three-phase firing pulse generator in a reactive-power compensator connected via a reactive-power transformer and a current transformer to a 50 Hz three-phase system. The reactive power compensator has for each phase of the three-phase current at least one air choke, which is connected via a current transformer and via an alternating-current switch via another sum-current transformer to a secondary winding of the reactive-power transformer. In addition, the reactive-power compensator has for each phase of the three-phase current at least one capacitor bank or a capacitor, which is connected via a current transformer and an alternating-current switch (13) to the sum-current transformer (20).

Abstract: A polyphase static reactive compensator comprising a main saturated reactor (SR1) connected in series with a number of smaller saturated reactors (SR2-4) of graded voltage rating. The smaller reactors are shunted by respective thyristor switches (TV2-TV4) so that selected combinations of reactors can be obtained to provide control of the overall operating voltage. The slope of the overall characteristic can be controlled by switching through successive reactor combinations. Further refinement of the overall characteristic can be obtained by phase control of the smallest reactor (SR4) thyristor switches (TV3) or, in an alternative form of the invention, by the use of a single reactor (SR1) having a primary winding, a closed mesh secondary winding (19) and a phase-controlled auxiliary reactor (AR, ACR) constituting a load on the closed mesh winding. The two forms of the invention may be combined in one equipment.

Abstract: Variable ratio transformer constructed around a control transformer comprising: two closed magnetic circuits each constructed around a ferromagnetic core. An alternating current magnetic field circulates in the first core and a direct current magnetic field circulates in the second core. The two circuits are located so as to define at least two common magnetic spaces in which the fields are superposed orthogonally. Around the first core is wound a primary winding, a secondary winding and, for a specific application in a three-phase circuit, a tertiary winding. A conventional transformer can be associated with the control transformer to reduce the load supported by the control transformer. The variable ratio transformer according to the invention can be used as a static balance compensator.