Electrically variable transmission with improved gradeability

An electrically variable transmission comprising:

• an input member to receive power from an engine;
• an output member;
• first and second motor/generators;
• a first, compound planetary gear set having a ring gear, a carrier and a sun gear;
• a second, simple planetary gear set having a ring gear, a carrier and a sun gear;
• said input member being continuously connected to said ring gear of said first gear set, and said output member being continuously connected to said carrier of said second gear set;
• said first motor/generator being continuously connected to said sun gear of said first gear set;
• said second motor/generator being continuously connected with said sun gear of said second gear set;
• a first torque transfer device selectively grounding said ring gear of said second gear set;
• a second torque transfer device selectively connecting said ring gear of said second gear set to said sun gear of said first planetary gear set;
• a third torque transfer device selectively grounding said carrier of said first gear set;
• a fourth torque transfer device selectively connecting said carrier of said first planetary gear set with said sun gear of said second planetary gear set;
• and
• a fifth torque transfer device selectively connecting said ring gear of said first planetary gear set with said sun gear of said second planetary gear set.