Patent ID: 7125362

Claim:
A powertrain system, comprising: a prime mover; a change-gear transmission including an input, at least two selectable gear ratios, and an output, wherein at least the prime mover selectively applies power to the transmission; and a power shunt including a first motor-generator and a second motor-generator, that selectively shunts at least a portion of the power applied to the transmission by one of the input and the output to the other one of the input and the output, wherein the first motor-generator selectively generates a power output from a rotational input, the second motor-generator selectively generates a rotational output from a power input, and wherein the ratio gears are engaged by a clutch and the power shunt is configured to route power applied to the transmission by one of the input and the output to the other one of the input and the output such that the rotational speed of a ratio gear is substantially similar to the rotational speed of an engaging clutch during a gear ratio change, wherein the first motor-generator is a generator and the second motor generator is a motor when driveline torque is positive.