To provide a turbocharger control method capable of restraining fluctuation in engine torque, when changing geometry of a diffuser.
When an air flow rate of a compressor of a turbocharger and a characteristic point of the pressure ratio cross a switching line in response to an operation state of an engine for a vehicle, a blade angle being the geometry of the respective variable diffusers is simultaneously changed between a little opening initial state of α=0° and a fully opening state of α=35°. In that case, since a rotating speed, the air flow rate and the pressure ratio of the compressor before and after changing the blade angle of the respective variable diffusers coincide on the switching line, the variation in the engine torque is restrained when changing the geometry of the respective variable diffusers.
| JPH0481598A | 1992-03-16 |
Yoshiki Kuroki
Kazuhiro Ueda