Abstract: A power converter includes: plural inverter units connected in parallel to a DC power supply, including a storage battery, on a DC side and a DC fuse in each of current paths between the DC power supply and the inverter units, the DC fuse configured to, when a short-circuit failure occurs in any of the inverter units, be blown in the current path between the DC power supply and the inverter unit having the short-circuit failure. The number of the inverter units is a number with which a condition that, when the DC fuse between the DC power supply and the inverter unit having the short-circuit failure is blown, none of a plurality of the DC fuses between the DC power supply and a plurality of other inverter units that do not have the short-circuit failure are blown is satisfied.

Abstract: The power conversion system includes a power conversion circuit, a power conversion control circuit including a charging control mode, and a command value generating part. The charging control mode is a mode in which the output voltage of the power conversion circuit is controlled so that an interconnection inductance receives an interconnection inductance voltage determined by the power supply voltage vector of the AC power supply and the voltage command value vector having a delay phase with respect to the power supply voltage vector and having a magnitude and a phase based on the command value. The command value generating part generates a second command value for operation of the charging control mode when the voltage of the storage battery falls below the over-discharge threshold.

Abstract: A control device for a power conversion device includes a voltage recognizing unit configured to detect a voltage at a linkage point of the plurality of power converters, and a control unit configured to control an amplitude and a frequency of a voltage to be output by a power converter to be controlled on the basis of active power and reactive power output by the power converter to be controlled in a case that the power converter to be controlled is caused to perform autonomous operation as a voltage source, and controls active power and reactive power to be output by the power converter to be controlled so as to compensate for excess or deficiency of active power and reactive power at the linkage point on a basis of an amplitude and a frequency of the voltage detected by the voltage recognizing unit.

Abstract: A power converter includes: plural inverter units connected in parallel to a DC power supply, including a storage battery, on a DC side and a DC fuse in each of current paths between the DC power supply and the inverter units, the DC fuse configured to, when a short-circuit failure occurs in any of the inverter units, be blown in the current path between the DC power supply and the inverter unit having the short-circuit failure. The number of the inverter units is a number with which a condition that, when the DC fuse between the DC power supply and the inverter unit having the short-circuit failure is blown, none of a plurality of the DC fuses between the DC power supply and a plurality of other inverter units that do not have the short-circuit failure are blown is satisfied.

Abstract: A control device for a power conversion apparatus that can prevent a rush current from flowing into a power converter. In a power conversion apparatus with a power converter connected with a DC power supply, a filter, and a switch connected with an AC power supply are connected in series in that order, a control device for the power conversion apparatus includes: a calculation unit configured to calculate, from a value of an AC current flowing between the power converter and the filter and impedance of the filter, an estimated value for AC power to be outputted by the power converter; and a control unit configured to control an action of the power converter in a state that the switch is open such that a difference between a target value for AC power and the estimated value falls within an allowable range set in advance.

Abstract: A power conversion device includes a power conversion circuit and a control device. The control device includes a virtual power generation device model unit and a control signal generation unit. The virtual power generation device model unit includes: a motor model unit; an AVR model unit; an angular velocity difference acquisition unit; and a power generator model unit. The control signal generation unit is configured to generate the pulse width modulation signal based on the current command value and an output current value from the power conversion circuit.

Abstract: The power conversion system includes a power conversion circuit, a power conversion control circuit including a charging control mode, and a command value generating part. The charging control mode is a mode in which the output voltage of the power conversion circuit is controlled so that an interconnection inductance receives an interconnection inductance voltage determined by the power supply voltage vector of the AC power supply and the voltage command value vector having a delay phase with respect to the power supply voltage vector and having a magnitude and a phase based on the command value. The command value generating part generates a second command value for operation of the charging control mode when the voltage of the storage battery falls below the over-discharge threshold.

Abstract: A power conversion device includes a three-level inverter circuit and an inverter control circuit for driving the three-level inverter circuit in a double carrier modulation manner. The inverter control circuit includes a command value calculating part generating three-phase output voltage command values, a command value correcting part outputting corrected command values by correcting to the three-phase output voltage command value, and a gate signal generating part generating a gate signal based on the corrected command values. The command value correcting part is configured to output a predetermined voltage command value corresponding to an end of a dead band instead of one AC voltage command value, and distribute a difference between the one AC voltage command value and the predetermined voltage command value in the dead band passage period to other two AC voltage command values, during a dead band passage period.

Abstract: A power conversion device includes a three-level inverter circuit and an inverter control circuit for driving the three-level inverter circuit in a double carrier modulation manner. The inverter control circuit includes a command value calculating part generating three-phase output voltage command values, a command value correcting part outputting corrected command values by correcting to the three-phase output voltage command value, and a gate signal generating part generating a gate signal based on the corrected command values. The command value correcting part is configured to output a predetermined voltage command value corresponding to an end of a dead band instead of one AC voltage command value, and distribute a difference between the one AC voltage command value and the predetermined voltage command value in the dead band passage period to other two AC voltage command values, during a dead band passage period.

Abstract: A power conversion device includes a three-phase voltage inverter, a two-phase/three-phase converter, a tertiary harmonic wave generator, an adder, a PWM controller, and a tertiary harmonic wave amplitude determining unit. The tertiary harmonic wave generator generates a sinusoidal tertiary harmonic wave signal synchronized with three-phase voltage command signals and having a frequency which is three times as high as that of the three-phase voltage command signal. Further, the tertiary harmonic wave generator includes a tertiary harmonic wave amplitude determining unit for determining the amplitude of the tertiary harmonic wave signal at which the power loss of a three-phase voltage inverter is minimized, based on a voltage amplitude command value responding to two-phase voltage command signals and an output power factor command value responding to an output request to a power system.

Abstract: A power conversion device includes a power conversion circuit and a control device. The control device includes a virtual power generation device model unit and a control signal generation unit. The virtual power generation device model unit includes: a motor model unit; an AVR model unit; an angular velocity difference acquisition unit; and a power generator model unit. The control signal generation unit is configured to generate the pulse width modulation signal based on the current command value and an output current value from the power conversion circuit.

Abstract: A power conversion device includes a three-phase voltage inverter, a two-phase/three-phase converter, a tertiary harmonic wave generator, an adder, a PWM controller, and a tertiary harmonic wave amplitude determining unit. The tertiary harmonic wave generator generates a sinusoidal tertiary harmonic wave signal synchronized with three-phase voltage command signals and having a frequency which is three times as high as that of the three-phase voltage command signal. Further, the tertiary harmonic wave generator includes a tertiary harmonic wave amplitude determining unit for determining the amplitude of the tertiary harmonic wave signal at which the power loss of a three-phase voltage inverter is minimized, based on a voltage amplitude command value responding to two-phase voltage command signals and an output power factor command value responding to an output request to a power system.

Abstract: Embodiments provide a power conversion system, a power supply system, and a power conversion device which can use effectively the generated power of the DC generator and the power charged into the power storage device. The power conversion system of the embodiments includes a first power conversion device, a second power conversion device, a third power conversion device, and a control device. The first power conversion device is connected between a DC generator and an electric power system. The second power conversion device is connected between a power storage device and the electric power system. The third power conversion device is connected between the DC generator and the power storage device. The control device sets operations of the first power conversion device, the second power conversion device and the third power conversion device on the basis of a DC power which the DC generator outputs and a DC power which is set.

Abstract: Embodiments provide a power conversion system, a power supply system, and a power conversion device which can use effectively the generated power of the DC generator and the power charged into the power storage device. The power conversion system of the embodiments includes a first power conversion device, a second power conversion device, a third power conversion device, and a control device. The first power conversion device is connected between a DC generator and an electric power system. The second power conversion device is connected between a power storage device and the electric power system. The third power conversion device is connected between the DC generator and the power storage device. The control device sets operations of the first power conversion device, the second power conversion device and the third power conversion device on the basis of a DC power which the DC generator outputs and a DC power which is set.