Hybrid electric gas turbine engine two speed transmission for low spool drive power injection and power extraction

A hybrid electric gas turbine engine two speed transmission for a low spool drive comprising:

• an engine structure proximate a compressor of the gas turbine engine;
• a low speed spool towershaft coupled to the engine structure;
• a low speed spool angled gearbox in operative communication with the towershaft and in operative communication with a low speed spool of the gas turbine engine;
• a transmission in operative communication with the low speed spool angled gearbox, wherein the transmission comprises a two speed transmission configured for hybrid electric low spool drive applications, the two speed transmission comprises clutch packs and an epicyclic geartrain configured to reduce a speed range at the low speed spool motor-generator;
• an accessory gearbox in operative communication with the transmission;
• and a low speed spool motor-generator in operative communication with the accessory gearbox, wherein the accessory gearbox is in operative communication with a first high speed spool motor-generator and a second high speed spool motor-generator, and wherein the accessory gearbox is in operative communication with a high speed spool via a high speed spool angled gearbox.

A process for a hybrid electric gas turbine engine two speed transmission for a low spool drive comprising:

• providing an engine structure proximate a compressor of the gas turbine engine;
• coupling a low speed spool towershaft to the engine structure;
• coupling a low speed spool angled gearbox in operative communication with the towershaft;
• coupling the low speed spool angled gearbox in operative communication with a low speed spool of the gas turbine engine;
• coupling a transmission in operative communication with the low speed spool angled gearbox, configuring the transmission as a two speed transmission configured for hybrid electric low spool drive applications, the two speed transmission comprises clutch packs and an epicyclic geartrain;
• configuring the clutch packs and epicyclic geartrain to reduce a speed range at the low speed spool motor-generator;
• coupling an accessory gearbox in operative communication with the transmission;
• and coupling a low speed spool motor-generator in operative communication with the accessory gearbox, wherein the accessory gearbox is coupled in operative communication with a first high speed spool motor-generator and a second high speed spool motor-generator, and wherein the accessory gearbox is coupled in operative communication with a high speed spool via a high speed spool angled gearbox.