System and method for ground fault monitoring in an aircraft

A ground fault monitoring system for an aircraft, comprising:

• a polyphase AC electric power source electrically connected to a polyphase rotary electric motor via a plurality of AC contactors;
• an AC/DC inverter electrically connected to the polyphase rotary electric motor;
• a DC power bus electrically connected to the AC/DC inverter;
• a plurality of sensors arranged to monitor a plurality of electric currents between the polyphase AC electric power source and the polyphase rotary electric motor;
• a first controller arranged to control the AC/DC inverter;
• and
• a second controller arranged to monitor the plurality of sensors and operatively connected to the plurality of AC contactors;
• wherein the second controller is operable to:
• monitor, via the plurality of sensors, the plurality of electric currents between the polyphase AC electric power source and the polyphase rotary electric motor,
• detect a ground fault based upon the plurality of electric currents, and
• deactivate the plurality of AC contactors in response to the ground fault.

A method for controlling an electrical system for an aircraft that includes a polyphase AC electric power source electrically connected to a polyphase rotary electric motor via a plurality of AC contactors, an AC/DC inverter electrically connected to the polyphase rotary electric motor, a first controller operably connected to the AC/DC inverter, and a DC power bus electrically connected to the AC/DC inverter, the method comprising:

• monitoring, via a plurality of sensors, a plurality of electric currents between the polyphase AC electric power source and the polyphase rotary electric motor;
• detecting, via a second controller in communication with the plurality of sensors, a fault based upon the plurality of electric currents;
• and
• deactivating, via the second controller, the plurality of AC contactors in response to the fault.