A power distribution system is described. The system includes a main ac busbar and an emergency ac busbar. A hybrid drive system includes an induction electrical machine and a prime mover, the rotor of the electrical machine and the driving end of the prime mover being mechanically coupled to a load by means of a mechanical linkage such as a gearbox. The system includes a first active rectifier/inverter having ac input terminals electrically connected to the main ac busbar, and dc output terminals. The system includes a second active rectifier/inverter having dc input terminals electrically connected to the dc output of the first active rectifier/inverter by a dc link, and ac output terminals electrically connected to the induction electrical machine. A blackout restart system includes a rectifier having ac input terminals selectively electrically connectable to the emergency ac busbar and dc output terminals selectively electrically connectable to the dc link.

A power distribution system includes at least a ground power unit, an aerial vehicle, and a power station. The ground power unit is configured to convert an input AC power into DC power output, wherein the ground power unit includes at least a first bus, second bus, and a third bus, wherein the first bus is configured to operate at a first voltage level referenced to the third bus, and wherein the second bus is configured to operate at a second voltage level referenced to the third bus that is different from the first voltage level. The aerial vehicle may include a plurality of motor-generators coupled to a respective plurality of turbines, wherein the plurality of motor-generators may be configured to be energized by power received from a tether. The power station may be electrically coupled to at least the first bus, the second bus, and the tether and configured to: (i) selectively energize the tether using the first bus; and (ii) responsive to detecting a fault by at least one motor-generator of the plurality of motor-generators, selectively energize the tether using the second bus and not the first bus.

Described herein are power conversion systems and related techniques which utilize a coupled split path (CSP) circuit architecture. The CSP structure combines switches, capacitors and magnetic elements in such a way that power is processed in multiple coupled split paths in a variety of voltage domains. These techniques are well suited for power conversion applications that have one or more input/output ports that have a wide voltage range, or if the application is interfacing with the ac line voltage and requires power-factor correction.

Disclosed is a novel and innovative class of buck-boost bidirectional inverters achieve ultra high efficiency in applications requiring converting of one or more low and variable DC voltages of one or more power sources (which may include a battery, a low-voltage DC sourse, or a set of PV soloar panels) to an AC voltage (e.g., connected to a grid) through a single-stage power conversion with step modulation.

The present invention relates to a power control apparatus for sub-modules in a Modular Multilevel Converter (MMC), which controls the supply of power to sub-modules in an MMC connected to an HVDC system and to a STATCOM. The power control apparatus includes a half-bridge circuit unit for switching multiple switches, converting an input voltage across P and N buses of the MMC into a relatively low voltage, and outputting the low voltage; a transformer for transferring the low output voltage (primary side), output through switching of the switches in the half-bridge circuit unit via switching of the switches, to a secondary side of the transformer; a DC/DC converter for converting an output voltage on the secondary side of the transformer; a photocoupler for outputting a reference signal corresponding to a magnitude of the secondary side output voltage of the transformer; a Pulse Width Modulation (PWM) control unit for controlling switching of the switches in the half-bridge circuit unit in response to the reference signal output from the photocoupler; and a starting circuit unit for supplying an initial starting voltage to the PWM control unit, wherein the PWM control unit is started in response to the starting voltage initially supplied from the starting circuit unit, and is configured to control switching of the switches in response to the reference voltage received from the photocoupler, and to receive the secondary side output voltage of the transformer as an operating voltage depending on the switching, thus being operated.

A power system 10 is provided with a power conversion device 110 connected to an input power supply 200, a battery 120 and a load 130 connected in parallel with each other to the output side of the power conversion device 110, and a control device 140 controlling charging/discharging of the battery 120, wherein the control device 140 receives output power of the power conversion device 110, determines, based on the received output power, charge or discharge power of the battery 120 such that the output power becomes close to a first value, and charges or discharges the battery 120 based on the determined charge or discharge power.

A power system 10 is provided with a power conversion device 110 connected to an input power supply 200, a battery 120 and a load 130 connected in parallel with each other to the output side of the power conversion device 110, and a control device 140 controlling charging/discharging of the battery 120, wherein the control device 140 receives output power of the power conversion device 110, determines, based on the received output power, charge or discharge power of the battery 120 such that the output power becomes close to a first value, and charges or discharges the battery 120 based on the determined charge or discharge power.

A controller of an inverter control apparatus includes an A/D conversion unit that performs digital conversion of an input signal when a signal for either an A/D converter start trigger or an A/D converter start trigger is input thereinto; a first inverter control unit that generates the A/D converter start trigger which starts the A/D conversion unit, based on A/D converter start timing information and a first carrier signal; a second inverter control unit that generates the A/D converter start trigger which starts the A/D conversion unit, based on A/D converter start timing information and a second carrier signal; and an A/D start factor selection unit that receives either the A/D converter start trigger or the A/D converter start trigger and selects an A/D start factor at a predetermined period timing of an operation period of the first carrier signal and the second carrier signal.

This disclosure provides control techniques for a resonant converter. In one embodiment, a resonant converter controller includes predictive gate drive circuitry configured to generate a predictive gate drive signal indicative of a time duration from a rising edge of a first drive signal for controlling a conduction state of a first inverter switch of a resonant converter system to a synchronous rectifier (SR) current zero crossing instant of a first SR switch of the resonant converter system, wherein the first tracking signal is based on at least the first drive signal and a voltage drop across the first SR switch. The resonant converter controller may also include SR gate drive shrink circuitry configured to generate an SR gate drive turn on delay signal to increase delay of SR on times in response to detection of a decrease in load current demand of the resonant converter system.

A method and an apparatus for decoupling output power of an inverter are provided. The method comprises: obtaining voltage amplitude instruction E* and voltage phase instruction * according to an output voltage and an output current of the inverter; obtaining an amplitude feedforward amount E.sub.ff and a phase feedforward amount .sub.ff according to an amplitude U of a grid voltage of the power grid, an amplitude E of the output voltage of the inverter, and a phase difference between the output voltage of the inverter.sub.[0] and the grid voltage; obtaining a reference voltage amplitude E.sub.ref according to the voltage amplitude instruction E* and the amplitude feedforward amount E.sub.ff, and obtaining a reference voltage phase .sub.ref according to the voltage phase instruction * and the phase feedforward amount .sub.ff; and regulating the output power of the inverter using the reference voltage amplitude E.sub.ref and the reference voltage phase .sub.ref.