Vehicle drive and method with electromechanical variable transmission

A vehicle drive comprising:

• a gear set comprising a sun gear, a ring gear, and planetary gears, the planetary gears coupling the sun gear to the ring gear, wherein the planetary gears are rotatably supported by a planetary gear carrier;
• a first motor/generator coupled to the sun gear of the gear set;
• a second motor/generator selectively coupled to at least one of (a) the planetary gear carrier of the gear set and (b) the ring gear of the gear set, wherein the second motor/generator is electrically coupled to the first motor/generator by an electrical power transmission system, wherein the first motor/generator and the second motor/generator are electrically coupled without an energy storage device configured to at least one of (a) provide electrical energy to the first motor/generator or the second motor/generator to power the first motor/generator or the second motor/generator and (b) be charged by electrical energy from the first motor/generator or the second motor/generator;
• an engine coupled to the ring gear of the gear set and selectively coupled to the second motor/generator;
• and
• a controller including a processing circuit configured to:
• operate the engine at a calculated speed;
• operate one of the first motor/generator and the second motor/generator at a calculated torque;
• and
• operate the other of the first motor/generator and the second motor/generator to maintain a voltage on the electrical power transmission system.