Abstract: A gas turbine engine having a first pressure spool and a second pressure spool includes a power transfer system to transfer mechanical power between the first pressure spool and the second pressure spool. The first pressure spool can include a first electric machine to convert mechanical power from the first pressure spool to a first electric power. A coupled electric machine having a first coupled rotor and a second coupled rotor can be rotatingly coupled to the first pressure spool and the second pressure spool, respectively. The coupled electric machine is configured to receive an output power (e.g., an output power from an AC/AC converter) to drive a winding of the coupled electric machine to enable power transfer between the first pressure spool and the second pressure spool. An AC/AC converter can be electrically disposed between the first pressure spool and the second pressure spool.

Abstract: A gas turbine engine having a first pressure spool and a second pressure spool includes a power transfer system to transfer mechanical power between the first pressure spool and the second pressure spool. The first pressure spool can include a first electric machine to convert mechanical power from the first pressure spool to a first electric power. A coupled electric machine having a first coupled rotor and a second coupled rotor can be rotatingly coupled to the first pressure spool and the second pressure spool, respectively. The coupled electric machine is configured to receive an output power (e.g., an output power from an AC/AC converter) to drive a winding of the coupled electric machine to enable power transfer between the first pressure spool and the second pressure spool. An AC/AC converter can be electrically disposed between the first pressure spool and the second pressure spool.