Charging system of spark ignition engine with two chargers

The purpose of the investigation was the application of two chargers systems in spark ignition engine and determining chargers' work parameters depending on throttle opening and engine's rotation speed. The system with small turbocharger or electrically driven charger and larger variable geometry turbocharger in parallel and series connection was examined. The engine used during the investigation was 1300 ccm displacement SI engine with modified intake and exhaust manifolds. Intake and exhaust manifold modification including only the implementation of chargers and sensors was done for experimental purposes. Specific values of maximum boost pressure were obtained by introducing a waste gate valve system with appropriate characteristics. The application of two chargers system as modification of naturally aspirated spark ignition engine allows to improve the torque flexibility rate.