초록 ▼

The invention includes an autotransformer for converting three-phase AC power to nine-phase AC power. The autotransformer includes three coils, each coil including a plurality of serial windings that together form a polygon. Nine output nodes are provided between adjacent winding pairs, the windings

The invention includes an autotransformer for converting three-phase AC power to nine-phase AC power. The autotransformer includes three coils, each coil including a plurality of serial windings that together form a polygon. Nine output nodes are provided between adjacent winding pairs, the windings sized and arranged such that adjacent output voltages are separated by 40 degree phase shift and such that output voltage magnitudes are essentially identical. Both step-down and unity gain input node sets are provided wherein, when three-phase AC supply lines are linked to the step-down input set the output voltage is stepped down and when the three-phase AC supply lines are linked to the unity gain input set the transformer gain is unity. The invention also includes an isolation transformer having characteristics similar to those of the autotransformer.

대표청구항 ▼

1. An autotransformer for converting three-phase AC power provided on first, second and third supply lines to nine-phase AC power on first through ninth output lines, the autotransformer comprising:a. first, second and third coils, each coil having a plurality of serial windings linked together to f

1. An autotransformer for converting three-phase AC power provided on first, second and third supply lines to nine-phase AC power on first through ninth output lines, the autotransformer comprising:a. first, second and third coils, each coil having a plurality of serial windings linked together to form a polygon; b. a step-down input set including first, second and third input nodes between adjacent windings and separated by 120 degrees, the first, second and third input nodes linkable to the first, second and third supply lines, respectively; and c. first through ninth output nodes between adjacent windings which are linkable to the first through ninth output lines; d. wherein, the voltage magnitude at each of the nodes is measured by a vector between a neutral point and the node, the windings are sized and arranged such that the phase shift between adjacent output nodes is essentially 40 degrees, the voltage magnitudes at each of the output nodes are essentially identical, the voltage magnitudes at each of the step-down input set nodes are essentially identical and each step-down input node voltage magnitude is greater than each output node voltage magnitude such that the transformer can be used as a step-down transformer.