Abstract: An engine is described having an engine control unit and two or more hydraulically operated wheels, wherein a fluid is flowed from an accumulator to the engine via the first wheel to assist in acceleration of the turbocharger in response to an acceleration signal from the engine control system and wherein the fluid is flowed from the engine to the accumulator via the second wheel to decelerate the turbocharger in response to a deceleration signal from the engine control unit. In one particular embodiment, the second wheel absorbs energy from the turbocharger in response to the deceleration signal from the engine control unit to decelerate the turbocharger. In some embodiments, the hydraulically operated wheels may be positioned on the same shaft of, and between, the turbine and compressor of the turbocharger.

Abstract: A turbocharged internal combustion engine having an engine control unit and apparatus coupled to the turbocharger, to assist in acceleration of the turbocharger in response to an acceleration signal from the engine control system and to decelerate the turbocharger in response a deceleration signal from the engine control unit. The apparatus absorbs energy from the turbocharger in response to the deceleration signal from the engine control unit to decelerate the turbocharger. The apparatus includes one or more hydraulic wheels on the same shaft of, and between, the turbine and compressor of the turbocharger, the one or more hydraulic wheels being driven in response to the acceleration signal to assist in acceleration of the turbocharger or absorb energy from the turbocharger shaft in response the deceleration signal.