Aircraft cabin blower system

An aircraft cabin blower system comprising:

• a cabin blower including a compressor configured to provide air to a cabin of the aircraft;
• a variable drive system configured to drive the compressor and including an electric variator and a summing gearbox, wherein the electric variator comprises a first electrical machine, a second electrical machine, and a power management system, the first and the second electrical machines being independently configured to work as electric motors and/or as power generators;
• and
• a main transmission configured, when operating in a blower mode, to receive mechanical power from a main gas turbine engine and input mechanical power to the summing gearbox in a forward direction;
• and configured, when operating in a starter mode, to receive mechanical power from the summing gearbox and input mechanical power to the main gas turbine engine;
• wherein the aircraft cabin blower system further includes a first one-way rotation device adapted to permit free rotation of the main transmission in the forward direction and to prevent rotation of the main transmission in a reverse direction opposite to the forward direction;
• wherein the first electrical machine is connected to the summing gearbox through a first auxiliary transmission, and the second electrical machine is connected to the summing gearbox through a second auxiliary transmission;
• and
• further comprising a second one-way rotation device adapted to permit free rotation of the second auxiliary transmission in the forward direction and to prevent rotation of the second auxiliary transmission in the reverse direction opposite to the forward direction.