摘要:
According to some aspects, a power conversion system for converting electrical power produced by a generator is provided. The power conversion system comprises at least one first power converter configured to convert alternating current from the generator to direct current, at least one second power converter configured to convert the direct current to alternating current, and least one controller configured to reconfigure the at least one first power converter to convert direct current to alternating current and/or to reconfigure the at least one second power converter to convert alternating current to direct current.
摘要:
A control scheme for reducing current imbalance between parallel bridge circuits in a power converter system is provided. The power converter can include a plurality of bridge circuits coupled in parallel to increase the output power capability of the power system. The parallel bridge circuits can be controlled pursuant to a control scheme for reducing current imbalance between the parallel bridge circuits. In particular, a pulse test can be performed in which a pulse is applied to each of the plurality of bridge circuits. The switch timing of the switching elements responsive to the pulse can be measured and analyzed to determine a timing difference adjustment for one or more of the switching elements of the plurality of bridge circuits. The timing difference adjustment can be stored and used to adjust all subsequent switching events in the parallel bridge circuits.
摘要:
An apparatus for zero voltage switching is disclosed. A system and method also perform the functions of the apparatus. The apparatus includes an MCT region module that defines a minimum current trajectory (“MCT”) for operation between a maximum positive power output to a maximum negative power output of a bidirectional DC-to-DC converter. The converter includes a dual active bridge series resonant converter. The MCT defines a boundary between a zero voltage switching (“ZVS”) region and a hard switching region. The apparatus includes an offset module that defines an offset to the MCT, the offset in the ZVS region, and an MCT control module that adjust switching of switches of the converter to maintain operation of the converter in the ZVS region between the maximum positive power output to a maximum negative power output along a trajectory defined by the MCT and the offset.
摘要:
An inverter comprises a first boost apparatus, a second boost apparatus, a first half-cycle switching network coupled to the first boost apparatus, wherein the first half-cycle switching network is configured such that a first three-level conductive path is formed when a voltage at a dc source is greater than an instantaneous value of a voltage at an output of the inverter and a first five-level conductive path is formed when the instantaneous value of the voltage at the output of inverter is greater than the voltage at the dc source.
摘要:
A power conversion system is disclosed that provides multiphase power, including phase voltages for each phase of the multiphase power. The system comprises a plurality of inverters that generate PWM output voltages based on PWM control signals. A plurality of inductive components is configured to receive the PWM output voltages to generate the phase voltages. The PWM output voltages cause circulating current flows through the inductive components. A voltage controller is employed that is responsive to the phase voltages to generate voltage modulation signals corresponding to the phase voltages. A plurality of current sharing channels are respectively associated with each of the plurality of inductive components and are configured generate current sharing modulation signals in response to the circulating current flows. The PWM control signals are generated based on modulation signals obtained by combining the current sharing modulation signals and voltage modulation signals.
摘要:
A control scheme for reducing current imbalance between parallel bridge circuits in a power converter system is provided. The power converter can include a plurality of bridge circuits coupled in parallel to increase the output power capability of the power system. The parallel bridge circuits can be controlled pursuant to a control scheme for reducing current imbalance between the parallel bridge circuits. In particular, a pulse test can be performed in which a pulse is applied to each of the plurality of bridge circuits. The switch timing of the switching elements responsive to the pulse can be measured and analyzed to determine a timing difference adjustment for one or more of the switching elements of the plurality of bridge circuits. The timing difference adjustment can be stored and used to adjust all subsequent switching events in the parallel bridge circuits.
摘要:
An uninterruptible power supply (UPS) system includes at least three UPSs configured to be connected in parallel to a common load. The system further includes control circuitry configured to support at least two redundant groups among the UPSs and to support at least two redundant subgroups among at least one of the redundant groups of UPSs. In this manner, a nested redundancy may be provided.
摘要:
A method and an arrangement in connection with a wind power plant, an electric drive of the wind power plant comprising two or more partial converters in parallel, which constitute a frequency converter of the electric drive, and each partial converter comprising a mains converter part, of which the nominal power of at least one differs from the nominal power of other mains converter parts, and in the method there is selected for use the smallest possible, individual mains converter part required by an operating point of the wind power plant, or a combination of mains converter parts.
摘要:
According to one aspect, embodiments of the invention provide a UPS system comprising an input, an output, a converter, an inverter configured to convert DC power into output AC power, and a controller configured to operate the inverter to introduce a voltage droop to the output AC power, wherein the controller includes an active power droop controller including a first moving average filter configured to sample instantaneous active power of the inverter to obtain instantaneous active power samples and calculate a first DC component of the instantaneous active power samples, and a first Min-Max filter configured to receive the first DC component of the instantaneous active power samples and output a second DC component of the instantaneous active power samples having a convergence time less than the first DC component, wherein the active power droop controller is configured to calculate the voltage droop based on the second DC component.
摘要:
The present invention relates in a first aspect to a galvanically isolated power converter assembly comprising a first set of electrically interconnected resonant power inverters configured for generating respective output voltages and output currents. The galvanically isolated power converter assembly further a first positive summing node and a first negative summing node configured to combining the output voltages and output currents of the first set of resonant power inverters and a first common load circuit comprising a positive load input and a negative load input. A galvanic isolation barrier comprises first and second common isolation capacitors electrically insulating the common load circuit. Each of the first and second common isolation capacitors possesses an official safety rating.