Engine Performance: System: Turbocharger: Operation: Compressor
The compressor is connected directly to the turbine by a shaft; therefore, any speed of the turbine wheel will be the same for the compressor wheel. No exhaust gas is actually passed into compressor. The spinning compressor forces more air/fuel mixture into intake manifold than would normally be drawn in under atmospheric pressure.
With a higher intake manifold pressure and denser charge available, more mixture is drawn into combustion chamber on piston intake stroke. A denser mixture results in more power output from engine. The faster the compressor spins, more air/fuel mixture is compressed into manifold. Thus, engine demand can be satisfied. See Fig 1.