An apparatus for supplying power to a high-capacity load includes a three-to-two phase transformer including an input side three-phase transformer terminal for connection to a three-phase supply grid and output side first and second output-side single-phase transformer terminals. A converter arrangement has a first partial converter including a first input-side, single-phase AC voltage terminal for the first output-side transformer terminal and a first single-phase output terminal. A second partial converter has a second input-side single-phase AC voltage terminal for the second output-side transformer terminal and a second single-phase output connector. The partial converters are mutually connectable by the output terminals in an output-side series and/or parallel circuit and form a single-phase load terminal for the high-capacity load. A method for supplying power to a high-capacity load is also provided.