| 摘要 |
PURPOSE:To preferably follow the output current waveform a command value and to reduce the disorder of the output current waveform of a reversible converter by limiting the sinusoidal current command value to zero level before the zero passing point of the respective sinusoidal waveforms. CONSTITUTION:A current command value is produced through a zero limiter 12 from the rear stage of a multiplier 10 to which an amplitude command signal AD and a frequency command signal FD are applied. A zero limiting reference command instructing unit 14 is provided at the front stage of a positive and negative switching arithmetic unit 16. The signals FD and AD are applied to the unit 14, the output from the unit 14 is applied to a zero limiter 12, and the other output therefrom is applied to the arithmetic unit 16 together with a current detection signal. Since the command value supplied to a current regulator 20 is thus started from the zero level of a sinusoidal wave by waiting until the actual output current becomes zero, the actual current value of the reversible converter 18 may preferably follow the sinusoidal current command value. |
