To provide an AC motor controller which can perform rectangular wave control even at higher rotation speed (rpm) while suppressing offset current generation.
Within one period of electric angle determined based on the output of a sensor 25, the controller 30 increases or decreases a variation in the voltage phase of rectangular wave voltage of each phase for each switching reference phase of each phase equally for each switching. The controller 30 includes a first control which calculates the total amount of voltage phase change of the rectangular wave voltage in each predetermined period, i.e., two or more periods of electric angle, and a second control which receives information relevant to the total amount from the first control at a frequency of once a predetermined period, and updates the phase difference for the switching reference phase of each phase. The second control sets the phase difference of n-th switching for the switching reference phase of each phase to n times of a unit increment or decrement which is obtained by dividing the total amount by the number of switching times within a predetermined period.
YAMADA KATASHIGE
| JP2009095144A | 2009-04-30 | |||
| JP2001333591A | 2001-11-30 |
Toshio Morita
Yutaka Horii
Nobuo Arakawa