SUPPERCHARGING PRESSURE CONTROLLING METHOD

摘要

PROBLEM TO BE SOLVED: To cope with an abnormal suppercharging pressure state without impairing the stable output state of an internal combustion engine. SOLUTION: In a supercharging system 1 for an internal combustion engine 2 using a turbocharger 4, actual suppercharging pressure Pa in an intake passage 3 is detected by a boost pressure sensor BS. On the basis of the actual suppercharging pressure Pa, an excessive suppercharging pressure state is evaluated in two stages by an error determining part 8. Normally, suppercharging pressure control is carried out by a vane opening signal Sθ. In a first stage error state, nozzle vane opening is corrected by a correction signal SA in a direction of reducing the suppercharging pressure by a specified quantity. In a second stage error state, the nozzle vane is fully released by a full release signal SB.