Abstract: Techniques and mechanisms for determining a mode of operation of a switched capacitor voltage regulator (SCVR). In an embodiment, a controller supports multiple modes of operation of the SCVR, wherein the modes each correspond to a different respective sequence of switch states of a converter core of the SCVR. One of the modes is to provide boost voltage regulation with the SCVR. The controller transitions seamlessly and autonomously between two modes based on respective reference switch states of the two modes. In another embodiment, a mode transition is performed based on a signal which a control sensor generates based on a rate of switch events of the voltage regulator, and predetermined reference information indicating current characteristics of the voltage regulator.

Abstract: A dual-input power conversion system includes a first primary side power network comprising a first hold-up capacitor, wherein the first primary side power network has inputs configured to be coupled to a first power source, and outputs coupled to a transformer, a second primary side power network comprising a second hold-up capacitor, wherein the second primary side power network has inputs configured to be coupled to a second power source, and outputs coupled to the transformer, and a secondary side power network having inputs coupled to a secondary side of the transformer, and outputs coupled to a load, wherein the first primary side power network and the second primary side power network are configured such that a voltage across one of the first hold-up capacitor and the second hold-up capacitor is maintained by a voltage reflected from the secondary side to a corresponding primary side.

Abstract: Systems and methods for controlling a dual active bridge converter are disclosed herein. Switch control signals are provided to respective switches of at least one bridge of a dual active bridge converter. Control circuitry causes the switch control signals to switch according to a first switching sequence. After causing the switch control signals to switch according to the first switching sequence, the control circuitry causes the switch control signals to switch according to a second switching sequence, distinct from the first switching sequence, to distribute switching losses among the switches.

Abstract: The present invention relates to a method for directional transmission of power in the form of energy packets via a transmission network. The power to be transmitted is adjustable at least one location x of each edge by a data and computer network. A data packet is biuniquely assigned to each energy packet, which data packet is formed in a control instance of the data and computer network by means of predictions. This data packet describes an optimized transport path via which optimized transport path a source transmits the physical power in a fixed transmission period T to a load for partial demand coverage. Furthermore, the data packet describes the power class of the energy packet, wherein this power class is defined by the temporal course of a nominal power Pnom(t) determined by predictions and by a remainder R(t) in the transmission period determined by a function of an uncertainty of the predictions.

Abstract: A system includes a transformer rectifier unit (TRU) including a backfeed sense module. A contactor is operatively connected to the TRU for selectively supplying DC power to a DC bus from the TRU with the contactor closed and isolating the DC bus from the TRU with the contactor opened. A contactor driver is operatively connected to receive a signal from the backfeed sense module and to control opening and closing of the contactor based on the signal. The contactor driver is configured to open the contactor upon receipt of the signal indicative of backfeed detected in the TRU.

Abstract: A transformer including a primary circuit with a primary inductor, a first secondary circuit with a first secondary inductor that is galvanically isolated from the primary inductor and coupled to the primary inductor, a second secondary circuit with a second secondary inductor that is galvanically isolated from the primary inductor and coupled to the primary inductor. The second secondary inductor is implemented redundantly with respect to the first secondary inductor, in particular such that the first secondary inductor encloses the second or the second encloses the first. The first and second secondary inductors are connected to one, or each to one, DC voltage source as well as each to a test circuit with a tapping point for tapping off a test voltage.

Abstract: An apparatus for converting power includes at least one impedance matching network which receives an electrical signal. The apparatus includes at least one AC to DC converter in communication with the impedance matching network. Also disclosed is a method for powering a load and an apparatus for converting power and additional embodiments of an apparatus for converting power.

Abstract: System and methods for passive power sharing of parallel sources are provided. Aspects include a first DC power supply including a first generator and a rectifier circuit, a second DC power supply including a second generator and a second rectifier, wherein a first output of the first DC power supply and a second output of the second DC power supply are commonly coupled at a common bus point, a first current sensing device coupled between the first output of the first DC power supply and the common bus point, a first generator controller configured to receive a first current signal from the first current sensing device, analyze the first current signal to determine a first voltage droop value based on the first current signal, and operate the first DC power supply to reduce a first voltage output of the first DC power supply by the first voltage droop value.

Abstract: Embodiments include redundant power supplies and method for fault detection in a redundant power supply. Aspects include monitoring a voltage at local output nodes of each phase of the redundant power supply, wherein the local output nodes are each connected to an output bus of the redundant power supply via a feedback path. Aspects also include creating an alert that a phase associated with the local output node has failed based on a determination that the voltage at the local output node is within a fault range.

Abstract: A control method of a power control device includes: receiving power from a power supply, distributing the power to at least one of a plurality of power conversion systems (PCSs), and transferring the power to a load using the at least one PCS. The power is distributed based on a load amount of power of each of the plurality of PCSs.

Abstract: A power switching circuit including a first DC/DC converter having a first input configured to receive a first input DC voltage, a second DC/DC converter having a first input configured to receive a second input DC voltage, a DC/AC inverter having a first input coupled to the output of the first DC/DC converter and a second input coupled to the output of the second DC/DC converter, the DC/AC inverter including n (n>2) switching legs, and at least one controller coupled to the first DC/DC converter, the second DC/DC converter, and the DC/AC inverter, the at least one controller configured to operate the DC/AC inverter to provide n AC signals to at least one load coupled to the DC/AC inverter by operating two of the n switching legs in a static state and n?2 of the n switching legs in a transition state.

Abstract: A method for charging electric consumers at an electricity grid with multiple phases may include measuring a phase current of each of the multiple phases of the electricity grid at a balance point. The method may also include determining to which of the multiple phases each electric consumer of the electric consumers is connected for charging via the balance point. Additionally, the method may include holding an unbalanced load of the multiple phases below an unbalanced load threshold value via communicating a power specification to each electric consumer connected for charging.

Abstract: This disclosure provides a PSR-PWM technique for high power active front-end inverters to damp a specific inter-harmonic that may cause relative sub-synchronous resonance in power system. Due to the strong interaction between wind power converters, photovoltaic converters, FACTS devices and HVDC transmission, low-frequency oscillations occur from a few Hz to dozens of Hz, or even high-frequency oscillations ranging from about 300-2000 Hz. Meanwhile, low-frequency oscillations ranging from 0.6 Hz to 7 Hz occur in the power supply systems of many electric locomotives. Even in the case of large-scale train outage, low-frequency oscillation will lead to abnormal locomotive dispatching system; in addition, the power grid voltage disturbance and flicker caused by a large number of high-power are furnaces and other nonlinear loads in the industrial field with a passband inter-harmonic frequency ranging from 0.05 Hz-90 Hz and so on are detected.

Abstract: A power conversion device including: a reactor formed such that a DC winding and a plurality of coupled windings are wound around one magnetic body, one end of the DC winding is connected to a voltage source, one end of each of the plurality of coupled windings is connected to another end of the DC winding, another end of each of the plurality of coupled windings is connected to each intermediate connection point between a plurality of upper and lower arms composed of switching elements, and magnetic fluxes generated by currents flowing through the DC winding and the coupled windings merge with each other in the same direction; and a control device for controlling the switching elements, wherein the upper arms or the lower arms are controlled by in-phase driving or interleave driving on the basis of the duty of switching operation.

Abstract: An apparatus includes an active bridge section with input terminals that receive power from a constant current source where the active bridge section operates at a fixed switching frequency. The apparatus includes a resonant section with a resonant inductor, a transformer and a resonant capacitor. The inductor is connected in series with a primary winding and the capacitor is connected in parallel with a secondary winding of the transformer. The resonant section is connected to an output of the active bridge section. The apparatus includes an output rectifier section that receives power from the resonant section and includes output terminals for connection to a load, and includes a controller that regulates output voltage to the load where the controller regulates output voltage to the load by controlling switching of the active bridge section. The fixed switching frequency of the active bridge section matches a resonant frequency of the resonant section.

Abstract: One example includes a utility power system. The system includes a power generator system, the power generator system comprising a generator step-up (GSU) transformer and a power generator. The power generator can be configured to provide generator power to a power transmission system via the GSU transformer in a feedback manner based on a predetermined setpoint. The system further includes a voltage droop compensation controller configured to monitor the generator power at a high-side of the GSU transformer and to adjust the predetermined setpoint based on the monitored generator power to substantially mitigate circulating currents.

Abstract: A bidirectional DC-to-DC converter include a first half-bridge circuit, a second half-bridge circuit, at least one transformer having a first primary winding and a second primary winding and at least one secondary winding. The first half-bridge circuit is designed to generate an AC voltage at the first primary winding, and the second half-bridge circuit is designed to generate an AC voltage at the second primary winding. At least one bidirectional power converter circuit is electrically coupled to the secondary winding in a bridge arrangement. The bridge arrangement has a first bridge connection pole and a second bridge connection pole. The power converter circuit includes a voltage limitation device having a switching element.

Abstract: A DC-DC converter includes a first full-bridge circuit and a second full-bridge circuit isolated by a transformer. The first full-bridge circuit includes switching elements, a first floating capacitor, and a second floating capacitor. The first full-bridge circuit operates in at least one of a full-bridge operation mode and a half-bridge operation mode. In switching of the operation mode, switching phases of the first full-bridge circuit are shifted in two portions in one cycle of a drive frequency, and shift amounts of the phases are determined such that positive and negative output voltages of the first full bridge circuit are balanced before and after the operation mode is switched.

Abstract: The present invention discloses a parallel connected power supply cabinet system which comprises a plurality of power supply cabinets electrically parallel connected. The power supply cabinet comprises a frame with a plurality of installation chambers formed from the top of the frame downwardly to the bottom of the same. A power distribution unit is installed in one of the installation chambers near the top of the frame. A plurality of power supply units installed in the rest of the chambers respectively. The power distribution unit controls the input power of the power supply cabinet.

Abstract: A power supply system may comprise a plurality of input buses and an output bus. A plurality of multi-input power supplies may be disposed between the plurality of input buses and the output bus. The plurality of multi-input power supplies may be configured to supply a predetermined amount of power to the output bus before and after a failure event. The failure event may comprise at least one of the following: a failure of a one of the plurality of multi-input power supplies and loss of power on one of the plurality of input buses. Each input to the power supply may include an independent power section to support near or full output power in the event of another input power loss. Any input line loss from an independent power bus/grid may provide line redundancy to the power supply and to the power system as an Uninterruptable Power Supply.

Abstract: The present invention discloses a hybrid transformation system based on three-phase voltage type PWM rectifier and multi-unit uncontrolled rectifier. The hybrid transformation system mainly consists of a three-phase reactor (L), a three-phase voltage type PWM rectifier module, an N-unit three-phase uncontrolled rectifier bridge module group, capacitors (C0-CN) and a DSP control circuit. An input end of the three-phase voltage type PWM rectifier module is in parallel connection with an input end of each three-phase uncontrolled rectifier bridge module. The three-phase voltage type PWM rectifier module may work in to situations, with load or without load, and the three-phase voltage type PWM rectifier module just does reactive power compensation when working without load. All modules of the three-phase uncontrolled rectifier bridge module group may work in to situations, with loads independently or all the outputs are in parallel connection and with a same load.

Abstract: A system and method for estimating current in a DC-DC converter are provided that estimate an output current of the DC-DC converter more accurately by correcting an output voltage of a CT sensor at an input terminal as a part of a current map and an efficiency map. The current map and the efficiency map are configured in a 2D form, since the output voltage of the CT sensor varies depending on the PWM duty.

Abstract: A method for controlling a modular converter, having a plurality of M converter cells, including an active AC-to-DC converter operable in one of a plurality of modes; a DC-to-DC converter; a secondary side of said AC-to-DC converter and a primary side of said DC-to-DC converter connected in parallel with a DC-link capacitor, wherein the primary sides of the converter cells are connected in series, with a first converter cell connected to a line, preferably a medium voltage line, providing an AC line voltage an M-th converter cell connected to a ground; operated by a method placing the converters in bypassed, active or diode mode.

Abstract: A light-emitting system is introduced herein. The light-emitting system includes an insulating substrate and a plurality of light-emitting units electrically-connected on the insulating substrate. Each of the plurality of light-emitting units includes a plurality of light-emitting diodes arranged as a bridge rectifier. A first part of the plurality of light-emitting diodes emits light during positive half cycles of an AC power signal. A second part of the plurality of light-emitting diodes emits light during negative half cycles of the AC power signal. The third part of the plurality of light-emitting diodes comprising at least one light-emitting diode emits light during both the positive half cycles and the negative half cycles of the AC power signal, wherein the plurality of light-emitting units including the plurality of light-emitting diodes arranged as a bridge rectifier is formed together in a light-emitting chip.

Abstract: In an embodiment, a compact factory assembled and tested cabinet-based Direct Current (DC) power system includes at least one Alternating Current (AC) to DC converter disposed in a cabinet as at least one interchangeable module. An AC input section is also disposed in the cabinet and supplies AC power to the converter(s). At least one other electrical component is disposed in the cabinet, possibly as a module and it receives DC power from the converter(s). Other embodiments are also disclosed.

Abstract: A device that determines a second side current imbalance of a DC-DC converter, wherein the second side is a center tap which includes a voltage measuring portion that measures a voltage drop of each connecting portion of the DC-DC converter, an average resistance calculating portion that calculates average resistance from the measured voltage drops, a saturation reference value calculating portion, and a saturation determination portion that compares the saturation reference value and the average resistance. By measuring the voltage drop of each contact portion after supplying a low voltage DC power to an output side, a determination can be made as to whether a product is saturated.

Abstract: Level voltage levels/states of charge are maintained among a plurality of high voltage DC electrical storage devices/traction battery packs that are arrayed in series to support operation of a hybrid electric vehicle drive train. Each high voltage DC electrical storage device supports a high voltage power bus, to which at least one controllable load is connected, and at least a first lower voltage level electrical distribution system. The rate of power transfer from the high voltage DC electrical storage devices to the at least first lower voltage electrical distribution system is controlled by DC-DC converters.

Abstract: A light-emitting system comprises: a first power input terminal and a second power input terminal; an insulating substrate; a first light-emitting-diode string formed on the insulating substrate comprising at least three light-emitting diodes placed sequentially in a first direction to allow a current flow through the at least three light-emitting diodes of the first light-emitting-diode string generally in the first direction; a second light-emitting-diode string formed on the insulating substrate comprising at least three light-emitting diodes placed sequentially in a second direction to allow a current flow through the at least three light-emitting diodes of the second light-emitting-diode string generally in the second direction; a third light-emitting-diode string comprising at least three light-emitting diodes placed sequentially in a third direction to allow a current flow through the at least three light-emitting diodes of the third light-emitting-diode string generally in the third direction.

Abstract: This invention relates to a control circuit for a buck power factor correction (PFC) stage. Buck PFC stages are commonly used in low cost, high efficiency power converters. These buck PFC stages are typically controlled using a very slow control loop with a crossover frequency of the order of 10 to 20 Hz. However, such a slow response is unsuitable for applications requiring overvoltage protection. The present invention overcomes the problems with the known control circuits for buck PFC stages by implementing a two stage control circuit having a fast outer loop control circuit and a slow inner loop control circuit. The fast outer loop control circuit is in operation during low load conditions and the slow inner loop control circuit is only active under load.

Abstract: The power supply device includes a transformer, a switching unit for driving a primary side of the transformer, a detection unit for detecting an output corresponding to a current flowing on the primary side, a transmission unit for transmitting an output voltage from a secondary side to the primary side, and a control unit for controlling an operation of the switching unit in accordance with an output from the transmission unit, in which, when a switching frequency for driving the switching unit falls within a predetermined frequency range including a resonant frequency of the transformer, the control unit controls the switching unit so as to shorten a turn-ON time of the switching unit in accordance with an output from the detection unit.

Abstract: The embodiment of present invention provides a three-phase AC (Alternating Current)-DC (Direct Current) converter circuit, conversion method and the control system thereof. The converter circuit includes a three-phase AC power source having a first output terminal, a second output terminal and a third output terminal; a first AC-DC conversion module, a second AC-DC conversion module and a third AC-DC conversion module electrically connected to the first output terminal, the second output terminal and the third output terminal of the three-phase AC power respectively, and respectively have N1 pieces, N2 pieces and N3 pieces of AC-DC converters which are connected in parallel; and a DC side output terminal electrically connected to the parallel-connected output terminals of the first AC-DC conversion module, the second AC-DC conversion module and the third AC-DC conversion module, wherein at least one of N1, N2 and N3 is greater than or equal to 2.

Abstract: The present invention provides a multi-terminal power conversion device, a multi-terminal power transfer device, and a power network system which allows an existing power grid to be divided into a plurality of power grids that can be interconnected together and operated stably via existing or new transmission lines. An inter-power grid asynchronous interconnection network system includes a multi-terminal power conversion device characterized by connecting together a plurality of asynchronous power grids including a bulk power grid and controlling power so that the sum of inflow power and outflow power is zero. An intra-power grid synchronous network system includes a power apparatus control terminal device with means for controlling power for a power apparatus installed in an autonomous power grid. A plurality of inter-power grid asynchronous interconnection network systems are connected to an intra-power grid synchronous network system to integrate the power control with communication control.

Abstract: A fraction rated conversion system for coupling a plurality of high voltage direct current (HVDC) power strings in parallel to an HVDC transmission system includes at least one fraction rated power converter coupled to the plurality of HVDC power strings and at least one capacitive device coupled to the at least one fraction rated power converter. The at least one fraction rated power converter and the at least one capacitive device regulate a differential voltage across each HVDC power string of the plurality of HVDC power strings to be substantially similar to each other.

Abstract: An AC power conversion system includes a first AC/DC converter to be coupled to a multi-phase AC power supply, a second AC/DC converter coupled in parallel with the first AC/DC converter to the multi-phase AC power supply, a first DC load in series with a first inductor coupled to a first positive DC terminal of the first AC/DC converter and a second negative DC terminal of the second AC/DC converter, and a second DC load in series with a second inductor coupled to a first negative DC terminal of the first AC/DC converter and a second positive DC terminal of the second AC/DC converter.

Abstract: A system includes first and second pluralities of single phase AC/DC power supplies each having an input for coupling to first and second phase voltages, respectively, in a polyphase power distribution system. The outputs of the power supplies are electrically connected in parallel for supplying DC current to a load at a substantially constant voltage. The system further includes a controller coupled to at least the first plurality of power supplies and configured to increase the DC current supplied to the load by at least one of the first plurality of power supplies in response to another one of the first plurality of power supplies shutting down. Various other systems, power supplies, controllers and methods are also disclosed.

Abstract: A circuit for connecting lower AC voltage-rated AC-DC power supplies with higher voltage power sources. A power line matching transformer connecting the source to the power supplies needs only to support the self-dissipation and output current mismatch between supplies. The circuit can also protect the line matching transformer from overheating in various fault scenarios.

Abstract: An energy recovery system is provided that can be used in place of a resistive termination. The energy recovery system can simulate the behavior and performance of a resistive termination, while recovering at least some of the energy that would otherwise have been dissipated within the termination. In one embodiment, the energy recovery system includes a rectification system having a plurality of tuned rectifier circuits and an RF input network to provide input power distribution to the plurality of tuned rectifier circuits and input impedance shaping to shape the collective input impedance of the plurality of tuned rectifier circuits as seen at the RF input port of the RF input network.

Abstract: A power conversion circuit system comprises a primary conversion circuit, a secondary conversion circuit, and a control circuit for controlling the primary and secondary conversion circuits. The primary conversion circuit comprises a primary full bridge circuit, which includes a bridge section composed of both a primary coil in a transformer and a primary magnetic coupling reactor in which two reactors are magnetically coupled, a first input/output port disposed between a positive bus bar and a negative bus bar of the primary full bridge circuit, and a second input/output port disposed between the negative bus bar of the primary full bridge circuit and a center tap of the primary coil in the transformer. The secondary conversion circuit has a configuration similar to that of the primary conversion circuit.

Abstract: A method is described for controlling a plurality of parallel-connected power converters 20a, 20b, each of which operates in accordance with a pulse width modulation (PWM) strategy defined by an independent voltage carrier signal and an independently controllable modulating sinusoidal voltage signal which are used to generate a PWM command signal for each PWM strategy. The voltage carrier signals of the PWM strategies have the same switching period and desynchronisation of the PWM command signals causes an unwanted circulating current to flow between the power converters 20a, 20b. The method thus comprises providing the independently controllable modulating sinusoidal voltage signal of the PWM strategy of at least one of the plurality of power converters 20a, 20b with a dc voltage offset to modify the PWM command signal of the at least one power converter and thereby increase the synchronisation of the PWM command signals so that the magnitude of any unwanted circulating current is reduced.

Abstract: The configurations of a single-phase dual buck-boost/buck power factor correction (PFC) circuit and a controlling method thereof are provided in the present invention. The proposed circuit includes a single-phase three-level buck-boost PFC circuit receiving an input voltage and having a first output terminal, a neutral-point and a second output terminal for outputting a first and a second output voltages, a single-phase three-level buck PFC circuit receiving the input voltage and coupled to the first output terminal, the neutral-point and the second output terminal, a first output capacitor coupled to the first output terminal and the neutral-point, a second output capacitor coupled to the neutral-point and the second output terminal, and a neutral line coupled to the neutral-point.

Abstract: A power converter is provided that has an alternating-current (AC) to direct-current (DC) switched-mode power converter circuit that converts alternating-current power into direct-current power for powering an attached electronic device. Power can be conserved by automatically placing the power converter circuit in a low-power standby mode of operation whenever the electronic device is detached from the power converter. A monitoring circuit can be powered by a capacitor or other energy storage element while the power converter is operating in the standby mode. If the monitoring circuit detects an output voltage change that is indicative of attachment of the electronic device or if the storage element needs to be replenished, the monitoring circuit can place the power converter circuit in an active mode of operation.

Abstract: A multi-path constant current drive circuit includes a DC/AC converter, a main transformer and at least two rectifying and filtering units. The main transformer includes at least one assistant side winding with a tap; together with the assistant side winding of the main transformer, each of the at least two rectifying and filtering units respectively forms a power supply loop; each power supply loop includes a first rectifying loop and a second rectifying loop, which are relatively used for the rectification of the positive and the negative half-cycle alternating voltage; a current-equalizing transformer is arranged between the adjacent first power supply loop and second power supply loop, the windings of the current-equalizing transformer are respectively in the rectifying loops contained in the first power supply loop and the second power supply loop, thus realizing the current equalization between the different rectifying loops in which the adjacent rectifying and filtering units are contained.

Abstract: The switched-mode power supply includes a switching cell having an inductive element with two connections and several individually selectable outputs, and in which the two connections of the inductive element are joined respectively to at least two of the individually selectable outputs. It is thus possible to generate and regulate at least two different voltages, one positive and one negative.

Abstract: A method of multi-path power factor correction includes providing a plurality of energy transfer paths from a voltage-varying input to an output; delivering a first fraction of available input energy to one or more energy storage networks at the input of at least one of the plurality of energy transfer paths; delivering a second fraction of available input energy to the output; and adjusting the first fraction and second fraction for facilitating outputting a substantially constant output and for controlling the energy drawn from the input.

Abstract: A multiphase controller for a DC-to-DC power supply includes logic to estimate parameters for multiple phases that provide a combined output at a load. The estimated parameters include a current estimate and an effective resistance estimates for each phase so that a power estimate for each phase can be produced. The logic adjusts the operation of the phases using the power estimate for each phase.

Abstract: The embodiment of present invention provides a three-phase AC (Alternating Current)-DC (Direct Current) converter circuit, conversion method and the control system thereof. The converter circuit includes a three-phase AC power source having a first output terminal, a second output terminal and a third output terminal; a first AC-DC conversion module, a second AC-DC conversion module and a third AC-DC conversion module electrically connected to the first output terminal, the second output terminal and the third output terminal of the three-phase AC power respectively, and respectively have N1 pieces, N2 pieces and N3 pieces of AC-DC converters which are connected in parallel; and a DC side output terminal electrically connected to the parallel-connected output terminals of the first AC-DC conversion module, the second AC-DC conversion module and the third AC-DC conversion module, wherein at least one of N1, N2 and N3 is greater than or equal to 2.

Abstract: A switched mode power supply allowing a half bridge converter to be use alone or in combination with another converter to form a full bridge converter. A common controller may be used for either half bridge or full bridge configurations. The modular approach simplifies design for a range of power supplies and reduces costs.

Abstract: A current sharing method and device for a DC power supply are provided, and the method includes: taking a latest detected bus current as a reference current to perform current sharing control on a local host current; calculating and timing sending time of the local host current according to the latest detected bus current, the local host current, and a preset corresponding relationship between a difference between the local host current and the bus current and the sending time of the local host current, and if no new bus current is detected within a timing time, sending the local host current as a new bus current to a bus when the timing times out. The method has small communication traffic and no master-slave relationship, and is simple to control, which reduces the difficulty of system development and improves the system reliability.

Abstract: Systems and methods are disclosed for maximizing the efficiency of a power supply according to the value of a load to be powered. One embodiment provides a power supply system including a first and second stage. The first stage has at least one AC to DC conversion section for converting an AC input to DC at an upper DC voltage value. The second stage has at least one DC to DC regulation section for converting at least a portion of the DC at the upper DC voltage value to DC at a lower DC voltage value and supplying the lower DC voltage value to a DC output. One or both of the first and second stages includes more than one section operating in parallel. A controller selectively enables a selected combination of the AC to DC conversion sections and the DC to DC regulation sections according to an expected or actual value of the load.

Abstract: A power converter includes at least two power conversion sections operating in parallel. The power converter receives a variable input power and generates an AC output voltage. When the power source is generating enough power to supply a DC voltage to the power converter greater than or equal to the peak magnitude of the desired AC voltage output, each power conversion section operates in parallel, converting the DC voltage to the desired AC voltage output. When the power generated by the variable power source results in a DC voltage having a magnitude less than the peak magnitude of the desired AC voltage output, the power conversion sections operate in series. One power conversion section operates as a boost converter to boost the DC voltage level to a suitable level for the second power conversion section, which generates the desired AC output voltage.