Abstract: A gear train includes a first planetary gear set including a first sun gear, a first ring gear, and a first carrier and a second planetary gear set including a second sun gear, a second ring gear, and second carrier. The gear train also includes a first clutch configured to selectively connect the first carrier with the second carrier and a second clutch configured to selectively connect the first sun gear with the second sun gear. The gear train also includes a first brake configured to selectively fix the first sun gear, a second brake configured to selectively fix the second sun gear, and a third brake configured to selectively fix the first carrier.

Abstract: An improved dual mode EPPV transmission hybrid electric drive system uses a combination of power sources including an internal combustion engine, a first electric motor, and a second electric motor, and provides more efficient operation and compact installation. The improved dual mode EPPV transmission hybrid electric drive system includes a first planetary gear set including a first sun gear linked to a first ring gear via a pinion on a first carrier, and a second planetary gear set including a second sun gear linked to a second ring gear via a pinion on a second carrier, wherein the various elements of the planetary gear sets are configured to allow a dual mode synchronous shift operation. The system includes a first clutch and a second clutch, both of which may be dry clutches, for changing the mode of the transmission from a high mode to a low mode and vice versa.