US Patent 7772953 Symmetrical auto transformer delta topologies

Various embodiments of multi-phase transformers are disclosed. Exemplary transformer includes primary windings, secondary windings and third windings. Primary windings, secondary windings and third windings may include sub windings coupled to form functions. Primary windings are coupled at ends to form a delta configurations. Secondary windings are coupled to primary windings. Third windings are coupled to primary windings and secondary windings. Secondary windings and the third windings are magnetically coupled to primary windings. The outputs at second ends of third windings are greater than the outputs at the second ends of secondary windings. In some embodiments, the outputs at adjacent second ends of the third windings are substantially equal. In some embodiments, the phase angle difference of outputs at adjacent second ends of third windings are substantially equal. In some embodiments, the phase angle difference of outputs at adjacent second ends of secondary windings are substantial equal.