Power conversion apparatus, control device for power conversion apparatus, and method for controlling power conversion apparatus

Patent metadata

Field	Value
Publication number	US-9407135-B2
Application number	US-201414564090-A
Country	US
Kind code	B2
Filing date	Dec 9, 2014
Priority date	Mar 26, 2014
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A power conversion apparatus includes a power converter, an LC filter, and a controller. The power converter is disposed between an AC power source and a load. The LC filter is disposed between the AC power source and the power converter. The controller controls the power converter to perform power conversion control between the AC power source and the load. The controller includes a command generator, an oscillation component acquirer, a regulator, and an actuator. The command generator generates an input current command including a command of an input current of the power converter. The oscillation component acquirer acquires an oscillation component of a current flowing through a capacitor of the LC filter. The regulator regulates the input current command based on the oscillation component acquired by the oscillation component acquirer. The actuator controls the power converter based on the input current command regulated by the regulator.

First claim

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A power conversion apparatus comprising:
a power converter disposed between an AC power source and a load;
an LC filter disposed between the AC power source and the power converter; and
a controller configured to control the power converter to perform power conversion control between the AC power source and the load, the controller comprising:
a command generator configured to generate an input current command comprising a command of an input current of the power converter;
an oscillation component acquirer configured to acquire an oscillation component of a current flowing through a capacitor of the LC filter;
a regulator configured to regulate the input current command based on the oscillation component acquired by the oscillation component acquirer; and
an actuator configured to control the power converter based on the input current command regulated by the regulator.

2. The power conversion apparatus according to claim 1 , further comprising a voltage detector configured to detect a voltage of the capacitor,
wherein the oscillation component acquirer comprises
a current estimator configured to estimate the current flowing through the capacitor based on the voltage of the capacitor detected by the voltage detector, and
an oscillation component extractor configured to extract an oscillation component from the current estimated by the current estimator.

3. The power conversion apparatus according to claim 2 , further comprising:
a phase detector configured to detect a voltage phase of the AC power source;
a correction amount calculator configured to calculate a phase correction amount based on the input current command regulated by the regulator; and
a phase determinator configured to determine a phase of the input current based on the phase correction amount calculated by the correction amount calculator and the voltage phase detected by the phase detector,
wherein the actuator is configured to control the power converter to make the phase of the input current match the phase determined by the phase determinator.

4. The power conversion apparatus according to claim 3 , further comprising a current calculator configured to subtract the oscillation component from the current estimated by the current estimator so as to calculate another current,
wherein the phase determinator is configured to determine the phase of the input current based on the current calculated by the current calculator, based on the phase correction amount calculated by the correction amount calculator, and based on the voltage phase detected by the phase detector.

5. The power conversion apparatus according to claim 1 , wherein the actuator is configured to control a phase of the input current based on the input current command regulated by the regulator.

6. The power conversion apparatus according to claim 1 , wherein the actuator is configured to determine a distribution ratio of the input current of the power converter based on the input current command regulated by the regulator and configured to control the power converter based on the determined distribution ratio.

7. A control device for a power conversion apparatus, the control device comprising:
an oscillation component acquirer configured to acquire an oscillation component of a current flowing through a capacitor of an LC filter disposed between a power converter and an AC power source, the power converter being configured to perform power conversion between the AC power source and a load;
a command generator configured to generate an input current command comprising a command of an input current of the power converter;
a regulator configured to regulate the input current command based on the oscillation component acquired by the oscillation component acquirer; and
an actuator configured to control the power converter based on the input current command regulated by the regulator.

8. A method for controlling a power conversion apparatus, the method comprising:
acquiring an oscillation component of a current flowing through a capacitor of an LC filter disposed between a power converter and an AC power source, the power converter being configured to perform power conversion between the AC power source and a load;
generating an input current command comprising a command of an input current of the power converter;
regulating the input current command based on the acquired oscillation component; and
controlling the power converter based on the regulated input current command.

9. The method according to claim 8 , further comprising detecting a voltage of the capacitor,
wherein the oscillation component acquiring step comprises
estimating the current flowing through the capacitor based on the detected voltage of the capacitor, and
extracting an oscillation component from the estimated current.

10. A power conversion apparatus comprising:
power converting means between an AC power source and a load;
an LC filter disposed between the AC power source and the power converting means; and
controlling means for controlling the power converting means to perform power conversion control between the AC power source and the load, the controlling means comprising:
command generating means for generating an input current command comprising a command of an input current of the power converting means;
oscillation component acquiring means for acquiring an oscillation component of a current flowing through a capacitor of the LC filter;
regulating means for regulating the input current command based on the oscillation component acquired by the oscillation component acquiring means; and
actuating means for controlling the power converting means based on the input current command regulated by the regulating means.

11. The power conversion apparatus according to claim 2 , wherein the actuator is configured to control a phase of the input current based on the input current command regulated by the regulator.

12. The power conversion apparatus according to claim 2 , wherein the actuator is configured to determine a distribution ratio of the input current of the power converter based on the input current command regulated by the regulator and configured to control the power converter based on the determined distribution ratio.

Assignees

• Yaskawa Electric Corp

Inventors

• Kinomura Hirofumi
• Saeki Takahiro

Classifications

• H02M1/126

  using passive filters · CPC title

• H02M1/4216 Primary

  operating from a three-phase input voltage (H02M1/4233 takes precedence) · CPC title

• H02M5/273

  with digital control · CPC title

• H02M5/297

  for conversion of frequency · CPC title

• Y02B70/126

  Cross-Sectional Technologies · mapped topic