Three-mode hybrid powertrain with two motor/generators

A hybrid powertrain for launching and propelling a vehicle, comprising:

• an engine;
• a first motor/generator;
• a second motor/generator,
• an electrically-variable transmission having:
• an output member;
• a stationary member;
• a first planetary gear set having a first, a second, and a third node, and a compound planetary gear arrangement having a fourth, a fifth, a sixth and a seventh node;
• and
• a first torque-transmitting device, a second torque-transmitting device and a third torque-transmitting device, wherein the first torque-transmitting device is engageable to ground the fourth node to the stationary member, the second torque-transmitting device is engageable to lock any one of the fourth, the fifth, the sixth and the seventh node to any other of the fourth, the fifth, the sixth and the seventh node, and the third torque-transmitting device is engageable to ground the seventh node to the stationary member;
• wherein:
• the engine is operatively connected to the first node, the first motor/generator is operatively connected to the third node, the second motor/generator is operatively connected to the second and to the sixth node, and the output member is operatively connected to the seventh node, such that the powertrain includes a forward under-drive mode for launching the vehicle, a forward direct-drive mode for propelling the vehicle at higher speeds, and a reverse mode for launching the vehicle.