| 摘要 |
PURPOSE:To reduce the number of switching elements by supplying two-phase three-wire AC power to the stator windings of a motor from the midpoints of two arms connecting plural switching elements in series. CONSTITUTION:AC power is subjected to doubler voltage rectification using a DC voltage source 4. A reference terminal G of a two-phase induction motor 20 is connected to its reference potential output terminal 9, while between positive and negative voltage output terminals 10 and 11, arms 12a and 12b connecting plural switching elements in series are connected. The midpoints 17 and 18 of the arms 12a and 12b are respectively connected to an A-phase terminal A and a B-phase terminal B of the two-phase induction motor 20. By turning ON and OFF switching elements 13 to 16 by the use of PWM, the two-phase induction motor 20 is driven. As compared with the case in conventional circuits two arms are dispensed with, so that the constitution can be simplified. |
