Patent ID: 7855473

Claim:
An apparatus for converting DC power to AC power, comprising: a DC to AC inverter; a phase rotation circuit, coupled to the DC to AC inverter, comprising (i) a first phase input terminal, a second phase input terminal, and a third phase input terminal; (ii) a first phase output terminal, a second phase output terminal, and a third phase output terminal; (iii) a first conductor coupling the first phase input terminal to the third phase output terminal, a second conductor coupling the second phase input terminal to the first phase output terminal, and a third conductor coupling the third phase input terminal to the second phase output terminal, wherein the DC to AC inverter couples power to at least one of the first, the second, or the third conductor; and (iv) a neutral conductor coupling a neutral input terminal to a neutral output terminal; a second phase rotation circuit; and a third phase rotation circuit, wherein (v) the first, the second, and the third phase output terminals are coupled to second phase rotation circuit input terminals and the neutral output terminal is coupled to a second phase rotation circuit neutral input terminal; (vi) second phase rotation circuit output terminals are coupled to third phase rotation circuit input terminals and a second phase rotation circuit neutral output terminal is coupled to a third phase rotation circuit neutral input terminal; and (vii) third phase rotation circuit output terminals and a third phase rotation circuit neutral output terminal are coupled to a fourth phase rotation circuit or to a commercial power grid.