| 摘要 |
PROBLEM TO BE SOLVED: To suppress change of a DC output voltage by breaking down input voltages of two or more sets of converters connected in series to d-axis and q-axis components of rotary coordinate axes, controlling them, and correcting the q-axis component in response to a difference of the output voltages of the respective converters. SOLUTION: AC powers from an AC voltage 5 are converted into DC powers by converters 1, 2 via transformers 3, 4 and supplied to capacitors 6, 7 and load 8. In the case of controlling the converters 1, 2, it is converted into effective current Iq and reactive current Id based on a voltage reference phase detected from a sine wave generator 17, and input voltages of the converters 1, 2 are controlled by an effective current controller 20 and reactive current controller 21. Thus, phases of a power source voltage and power source current coincide, and power factor of the power source can be controlled to '1'. Simultaneously, an output of a voltage controller 15 is set to an effective current command Iq*, thereby maintaining a combined DC voltage E of the converters constantly. |
