Patent ID: 7305828

Claim:
A boost pressure control method for an internal combustion engine comprising two intake-and-exhaust units, each intake-and-exhaust unit comprising an intake passage, an exhaust passage, a turbocharger which supercharges intake air in the intake passage using exhaust energy in the exhaust passage, the turbocharger having a regulating device which regulates a boost pressure, and an exhaust gas recirculating device which recirculates a part of exhaust gas in the exhaust passage to the intake passage, the exhaust gas recirculating device having a valve which regulates a recirculated exhaust gas flow rate in accordance with an opening thereof, the boost pressure control method comprising: detecting an opening of each exhaust gas recirculation valve; calculating an opening difference between the exhaust gas recirculation valves of the two intake-and-exhaust units; calculating a control amount of each regulating device on the basis of the opening difference between the exhaust gas recirculation valves such that the boost pressures of the turbochargers in the two intake-and-exhaust units match; and controlling each regulating device according to the control amount.