A sequential extraction control device for use in a 3-phase DC/AC converter. The 3-phase converter has three single-phase DC/AC converter each controlled by a respective PWM extractor. Duty factor adjustments are made depending on a current portion of an AC power cycle. A sequential regulator causes the PWM extractors to have non-overlapping duty cycles such that extraction of each of the single-phase DC/AC converters is performed in sequence, rather than concurrently. This improves the efficiency in extracting power from the DC power.