초록 ▼

A voltage control rate of an inverter has a DC component and an AC component. This AC component has a frequency which is six times a fundamental frequency of an AC voltage outputted by the inverter. Even when there are not only a fifth-order harmonic component but also a seventh-order harmonic compo

A voltage control rate of an inverter has a DC component and an AC component. This AC component has a frequency which is six times a fundamental frequency of an AC voltage outputted by the inverter. Even when there are not only a fifth-order harmonic component but also a seventh-order harmonic component of a load current, a ratio between the magnitude of the AC component and the DC component can be appropriately set.

대표청구항 ▼

1. A power converter control method for controlling a direct-type AC power converter, said direct-type AC power converter comprising: a rectifier circuit having a first AC voltage inputted thereto and outputting a rectified voltage; anda voltage-source inverter having said rectified voltage inputted

1. A power converter control method for controlling a direct-type AC power converter, said direct-type AC power converter comprising: a rectifier circuit having a first AC voltage inputted thereto and outputting a rectified voltage; anda voltage-source inverter having said rectified voltage inputted thereto and outputting a second AC voltage,wherein a voltage control rate of said voltage-source inverter has a DC component and an AC component whose frequency is six times a fundamental frequency of said second AC voltage. 2. The power converter control method according to claim 1, wherein a ratio of the absolute value of said AC component of said voltage control rate with respect to said DC component of said voltage control rate is equal to a ratio of the absolute value of a fifth-order harmonic component of a current flowing in the output side of said voltage-source inverter with respect to the absolute value of a fundamental wave component of said current. 3. A power converter controlled by the power converter control method according to claim 2, said power converter comprising said rectifier circuit and said voltage-source inverter. 4. The power converter control method according to claim 1, wherein a ratio of the absolute value of said AC component of said voltage control rate with respect to said DC component of said voltage control rate is equal to a ratio of the sum of the absolute value of a fifth-order harmonic component and the absolute value of a seventh-order harmonic component of a current flowing in the output side of said voltage-source inverter with respect to the absolute value of a fundamental wave component of said current. 5. A power converter controlled by the power converter control method according to claim 4, said power converter comprising said rectifier circuit and said voltage-source inverter. 6. The power converter control method according to claim 1, wherein said second AC voltage has three phases,said voltage control rate is updated in each 60-degree section of a phase of said second AC voltage. 7. A power converter controlled by the power converter control method according to claim 6, said power converter comprising said rectifier circuit and said voltage-source inverter. 8. The power converter control method according to claim 1, wherein said voltage-source inverter is controlled by a pulse-width modulation based on a result of comparison between a carrier and a signal wave,said signal wave is determined in accordance with a space vector modulation based on said voltage control rate and a command value of each of the amplitude, the phase, and the frequency of said second AC voltage. 9. A power converter controlled by the power converter control method according to claim 8, said power converter comprising said rectifier circuit and said voltage-source inverter. 10. A power converter controlled by the power converter control method according to claim 1, said power converter comprising said rectifier circuit and said voltage-source inverter. 11. A power converter control method for controlling a direct matrix converter which is a direct-type AC power converter and which has a first AC voltage inputted thereto and outputs a second AC voltage, wherein in a virtual AC/DC/AC control in which a virtual rectifier circuit for virtually rectifying said first AC voltage to obtain a virtual rectified voltage and a virtual voltage-source inverter for obtaining said second AC voltage from said virtual rectified voltage are assumed,a voltage control rate of said virtual voltage-source inverter has a DC component and an AC component whose frequency is six times a fundamental frequency of said second AC voltage. 12. The power converter control method according to claim 11, wherein a ratio of the absolute value of said AC component of said voltage control rate with respect to said DC component of said voltage control rate is equal to a ratio of the absolute value of a fifth-order harmonic component of a current flowing in the output side of said virtual voltage-source inverter with respect to the absolute value of a fundamental wave component of said current. 13. A direct matrix converter controlled by the power converter control method according to claim 12. 14. The power converter control method according to claim 11, wherein a ratio of the absolute value of said AC component of said voltage control rate with respect to said DC component of said voltage control rate is equal to a ratio of the sum of the absolute value of a fifth-order harmonic component and the absolute value of a seventh-order harmonic component of a current flowing in the output side of said virtual voltage-source inverter with respect to the absolute value of a fundamental wave component of said current. 15. A direct matrix converter controlled by the power converter control method according to claim 14. 16. The power converter control method according to claim 11, wherein said second AC voltage has three phases,said voltage control rate is updated in each 60-degree section of a phase of said second AC voltage. 17. A direct matrix converter controlled by the power converter control method according to claim 16. 18. The power converter control method according to claim 11, wherein said virtual voltage-source inverter is controlled by a pulse-width modulation based on a result of comparison between a carrier and a signal wave,said signal wave is determined in accordance with a space vector modulation based on said voltage control rate and a command value of each of the amplitude, the phase, and the frequency of said second AC voltage. 19. A direct matrix converter controlled by the power converter control method according to claim 18. 20. A direct matrix converter controlled by the power converter control method according to claim 11.