Hybrid transmission with three planetary gear sets and two interconnecting members and with synchronous shift between series and compound-split operating modes

A hybrid transmission operatively connected with an engine, comprising:

• an input member operatively connected with the engine;
• an output member;
• a first and a second selectively engageable torque-transmitting mechanism;
• a first, a second, and a third planetary gear set, each of the planetary gear sets having a first, a second, and a third member;
• wherein the input member is connected for common rotation with the first member of the first planetary gear set;
• wherein the output member is connected for common rotation with the third member of the third planetary gear set;
• a first motor/generator operatively connected with the second member of the first planetary gear set;
• a second motor/generator operatively connected with the second member of the third planetary gear set;
• a first interconnecting member continuously connecting the third member of the first planetary gear set for common rotation with the first member of the second planetary gear set and with the first member of the third planetary gear set;
• a second interconnecting member continuously connecting the second member of the second planetary gear set for common rotation with the second member of the third planetary gear set;
• a first torque-transmitting mechanism selectively engageable to ground the first interconnecting member to a stationary member to establish a hybrid series operating mode between the input member and the output member;
• a second torque-transmitting mechanism selectively engageable to connect the second member of the first planetary gear set for common rotation with the third member of the second planetary gear set to establish a compound-split operating mode between the input member and the output member;
• and
• wherein a shift between the hybrid series operating mode and the compound-split operating mode is synchronous without slipping the torque-transmitting mechanisms.

A hybrid transmission operatively connected with an engine, comprising:

• an input member operatively connected with the engine;
• an output member;
• only a first and a second selectively engageable torque-transmitting mechanism;
• a first, a second, and a third planetary gear set, each of the planetary gear sets having a first, a second, and a third member;
• wherein the input member is connected for common rotation with the first member of the first planetary gear set;
• wherein the output member is connected for common rotation with the third member of the third planetary gear set;
• a first motor/generator operatively connected with the second member of the first planetary gear set;
• a second motor/generator operatively connected with the second member of the third planetary gear set;
• a first interconnecting member continuously connecting the third member of the first planetary gear set for common rotation with the first member of the second planetary gear set and with the first member of the third planetary gear set;
• a second interconnecting member continuously connecting the second member of the second planetary gear set for common rotation with the second member of the third planetary gear set;
• a first torque-transmitting mechanism selectively engageable to ground the first interconnecting member to a stationary member to establish a hybrid series operating mode between the input member and the output member;
• a second torque-transmitting mechanism selectively engageable to connect the second member of the first planetary gear set for common rotation with the third member of the second planetary gear set to establish a compound-split operating mode between the input member and the output member;
• wherein a shift between the hybrid series operating mode and the compound-split operating mode is synchronous without slipping the torque-transmitting mechanisms;
• wherein the first member of the first planetary gear set is a carrier member, the second member of the first planetary gear set is a sun gear member, and the third member of the first planetary gear set is a ring gear member;
• wherein the first member of the second planetary gear set is a carrier member, the second member of the second planetary gear set is a ring gear member, and the third member of the second planetary gear set is a sun gear member;
• wherein the first member of the third planetary gear set is a carrier member, the second member of the third planetary gear set is a sun gear member, and the third member of the third planetary gear set is a ring gear member;
• and
• wherein one of the motor/generators is operable to start the engine when the first torque-transmitting mechanism is engaged and the second torque-transmitting mechanism is not engaged.