Abstract: An apparatus includes an isolated power converter having an input connected to an input dc power source, a first output and a second output, and a non-isolated power converter having an input connected to the second output of the isolated power converter, wherein the first output of the isolated power converter and an output of the non-isolated power converter are connected in series.

Abstract: An apparatus includes a controller configured to generate a PWM signal for controlling a power switch of a forward converter, a bias switch and a bias capacitor connected in series and coupled to a bias winding of the forward converter, and a comparator having a first input connected to the bias capacitor, a second input connected to a predetermined reference and an output configured to generate a signal for controlling the bias switch to allow a magnetizing current from the bias winding to charge the bias capacitor when a voltage across the bias capacitor is less than the predetermined reference.

Abstract: According to one aspect, an apparatus comprising a two stage DC-DC converter is provided. The converter consists of a multilevel DC-DC converter stage cascaded with a fixed voltage ratio DC-DC converter stage. The converter is controlled so that a first stage of the converter provides an optimized output (a regulated bus voltage) which serves as the input to the second stage. The multilevel DC-DC converter may be the first stage and the fixed voltage ratio, unregulated DC-DC converter may be the second stage converter. Alternatively, the fixed voltage ratio, unregulated DC-DC converter may be the first stage and the multilevel DC-DC converter may be the second stage.

Abstract: A bidirectional power conversion system includes three power conversion ports. A first power conversion port includes a power factor correction device and a primary power conversion network. A second power conversion port includes a plurality of switches and a plurality of diodes, wherein an output voltage of the second power conversion port is regulated through adjusting an output voltage of the power factor correction device as well as through adjusting an operating parameter of the primary power conversion network. A third power conversion port includes a first switch network and a power regulator connected in cascade, wherein the first power conversion port, the second power conversion port and the third power conversion port are magnetically coupled to each other through a transformer.

Abstract: A system includes a plurality of power modules connected in series between two input terminals of an inverter, a plurality of local controllers coupled to their respective power modules, wherein a first local controller of the plurality of local controllers is coupled to a first power module comprising a first solar panel, a first capacitor and a first power optimizer, and wherein the first local controller is configured to enable the first power optimizer to switch among a buck mode, a boost mode and a pass-through mode based upon a maximum power point tracking (MPPT) current of the first solar panel, and a central controller coupled to the inverter, wherein the central controller is configured to regulate an input voltage of the inverter.

Abstract: A system includes a current-mode switcher configured to provide a direct current (DC) voltage for a noise sensitive load, and a linear amplifier connected to an output of the current-mode switcher, the linear amplifier configured to draw a reduced supply voltage through at least one power conversion device that is coupled between a power source and the linear amplifier.

Abstract: A multi-level converter includes a first blocking device, a second blocking device, a first switching element and a second switching element connected in series between an output terminal of the multi-level converter and ground, a first soft switching apparatus comprising a first auxiliary switch and a first transformer, wherein the first auxiliary switch and the first transformer are configured the first switching element is of zero voltage switching, and the first auxiliary switch is of zero current switching, and a second soft switching apparatus comprising a second auxiliary switch and a second transformer, wherein the second auxiliary switch and the second transformer are configured the second switching element is of zero voltage switching, and the second auxiliary switch is of zero current switching.

Abstract: According to one aspect of the present disclosure, there is provided an apparatus that includes a battery, a Direct Current (DC) bus connected to the battery, and a DC to DC converter connected to the battery in parallel with the DC bus. A Motor Control Unit (MCU) is connected between the DC to DC converter and an electric motor. An Alternating Current (AC) port is connected to the electric motor. Switches connect the DC bus and an output of the DC to DC converter in series as an input to the MCU in a drive mode and disconnect the DC bus from the MCU in a charge mode.

Abstract: An apparatus includes a controller configured to generate a PWM signal for controlling a power switch of a forward converter, a bias switch and a bias capacitor connected in series and coupled to a bias winding of the forward converter, and a comparator having a first input connected to the bias capacitor, a second input connected to a predetermined reference and an output configured to generate a signal for controlling the bias switch to allow a magnetizing current from the bias winding to charge the bias capacitor when a voltage across the bias capacitor is less than the predetermined reference.

Abstract: A power conversion system includes a first power conversion port including a three-level power factor correction device and a primary power conversion circuit, a second power conversion port including a three-level rectifier and a third power conversion port including a rectifier, the first power conversion port, the second power conversion port and the third power conversion port magnetically coupled to each other through a transformer.

Abstract: An apparatus includes a pulse-width modulation (PWM) generator configured to generate a PWM signal for controlling a power switch of a power converter, a bias switch and a bias capacitor connected in series and coupled to a magnetic winding of the power converter and a comparator having a first input connected to the bias capacitor, a second input connected to a predetermined reference and an output configured to generate a signal for controlling the bias switch to allow a magnetizing current from the magnetic winding to charge the bias capacitor when a voltage across the bias capacitor is less than the predetermined reference.

Abstract: A method includes detecting a voltage signal of a three-level power converter, the voltage signal indicative of a capacitor voltage balancing in the three-level power converter, and dynamically adjusting an operating variable to adjust the voltage signal until the capacitor voltage balancing in the three-level power converter satisfies a criteria.

Abstract: System, device and method for exporting power are provided including at least one AC optimizer with plurality of DC inputs each connecting with respective one of plurality of DC sources, and independent maximum power point tracking (MPPT) performed for each respective DC source to extract power from each DC source for output and coupling to AC grid. When multiple AC optimizers are employed, with each AC optimizer having multiple DC inputs, each DC input can be connected to PV module with independent MPPT function. Since, each AC optimizer can serve multiple PV modules, significant cost saving and efficiencies can be achieved. Optionally, on PV sub-module level, each of the multiple DC inputs can be used as an independent MPPT channel for a PV sub-module cell string.

Abstract: According to one aspect of the present disclosure, there is provided an apparatus that includes first, second, and third power converter stages connected to a transformer module. At least one of the first, second, and third power converter stages is a multi-level power converter stage that has multiple configurations to generate different output voltages from an input voltage.

Abstract: A direct current (DC) bus voltage from a combined output of a plurality of DC power modules is controlled based on an alternating current (AC) voltage of a power grid. The DC bus voltage tracks the AC grid voltage to provide efficient conversion between the DC power sources and the AC grid, even when the amplitude of the AC grid voltage varies. In one example, a variable reference voltage is generated based on a detected AC grid voltage. The reference voltage increases and decreases in proportion to increases and decreases in the AC grid voltage. In this manner, large differences between the bus voltage and the grid voltage are avoided. By closely tracking the two voltages, efficiency in the modulation index for power conversion can be achieved.

Abstract: An apparatus having an AC rectifier configured to generate one or more rectified signals from an alternating current (AC) signal, bus having a positive line and a negative line, parallel converter connected between the positive line and the negative line, and bulk capacitor coupled to the parallel converter. The bus is connected to the AC rectifier to receive a first of the rectified signals between the positive line and the negative line. The apparatus has a controller configured to operate the parallel converter in a first mode in which energy from a second of the rectified signals from the AC rectifier is stored in the bulk capacitor and a second mode in which the energy stored in the bulk capacitor is discharged to the bus to increase a voltage on the bus during at least an initial portion of the second mode.

Abstract: A multi-level converter includes a first blocking device, a second blocking device, a first switching element and a second switching element connected in series between an output terminal of the multi-level converter and ground, a first soft switching apparatus comprising a first auxiliary switch and a first transformer, wherein the first auxiliary switch and the first transformer are configured the first switching element is of zero voltage switching, and the first auxiliary switch is of zero current switching, and a second soft switching apparatus comprising a second auxiliary switch and a second transformer, wherein the second auxiliary switch and the second transformer are configured the second switching element is of zero voltage switching, and the second auxiliary switch is of zero current switching.

Abstract: A direct current (DC) bus voltage from a combined output of a plurality of DC power modules is controlled based on an alternating current (AC) voltage of a power grid. The DC bus voltage tracks the AC grid voltage to provide efficient conversion between the DC power sources and the AC grid, even when the amplitude of the AC grid voltage varies. In one example, a variable reference voltage is generated based on a detected AC grid voltage. The reference voltage increases and decreases in proportion to increases and decreases in the AC grid voltage. In this manner, large differences between the bus voltage and the grid voltage are avoided. By closely tracking the two voltages, efficiency in the modulation index for power conversion can be achieved.

Abstract: A system includes a first power conversion device connected to a first power source, a first isolated power conversion device connected to the first power source, and a second power conversion device connected to the first isolated power conversion device, wherein outputs of the first power conversion device and outputs of the second power conversion device are connected in series, and series-connected outputs of the first power conversion device and the second power conversion device are configured to drive a motor.

Abstract: A system includes a first switched-capacitor converter including a plurality of switches connected in series, a second switched-capacitor converter, and a third switched-capacitor converter connected in parallel with the second switched-capacitor converter between a common node of two switches of the plurality of switches and a load, the second switched-capacitor converter and the third switched-capacitor converter both including inductors.