Variable exhaust-gas turbocharger with an auxiliary drive for an internal combustion engine

A variable exhaust gas turbocharger (1) for an internal combustion engine (10), comprising an exhaust gas turbine (2) including a housing having a turbine inlet flow passage (2.3) with a variable flow cross-section, a turbine wheel (2.2), a charge air compressor (3) with a charge air compressor wheel (3.1) disposed in said housing, a shaft (1.2) rotatably supported in said housing and carrying both said turbine wheel (2.2) and said compressor wheel (3.1), means for conducting exhaust gas from said combustion engine (10) to said turbine wheel (22) for driving the turbine wheel (2.2) with a first torque, an additional device (6) disposed in communication with said exhaust gas turbocharger (1) for supplying a second torque to said exhaust gas turbocharger, said additional device (6) being a compressor with a charge air inlet (3.6) and a charge air outlet (3.3) in communication with the compressor inlet of the exhaust gas turbocharger for supplying a second torque to the compressor wheel (3.1) and the turbocharger shaft, said charge air outlet of said additional compressor (6.2) including a main flow duct branching into two separate ducts, one being connected to an additional axial inlet duct (3.4) of the charge air compressor (3) and the other extending to a radial inlet duct (3.3a) of said compressor, said additional device (6) being driven by one of a mechanical drive and an electric motor.