A method for diagnosing a waste gate valve malfunction in a power generation system is presented. The method includes determining an actual pressure differential across a throttle valve. The method further includes determining an estimated pressure differential across the throttle valve based on one or more first operating parameters of the power generation system. Furthermore, the method includes determining an absolute difference between the actual pressure differential and the estimated pressure differential. Moreover, the method also includes comparing the absolute difference with a threshold value and if the absolute difference is greater than the threshold value, determining an operating condition of the throttle valve. Additionally, the method includes determining whether the waste gate valve has malfunctioned based on the determined operating condition of the throttle valve. An engine controller and a power generation system employing the method are also presented.

Methods and systems are provided for controlling a boosted engine system, having a turbocharger and a charge air cooler, to limit overheating of a compressor outlet. In one example, a method includes predicting an engine torque profile based on current and future engine operating conditions. The method then models a compressor outlet temperature profile and reduces engine torque output to limit overheating of the compressor outlet.

Methods and systems are provided for controlling a boosted engine system, having a turbocharger and a charge air cooler, to limit overheating of a compressor outlet. In one example, a method includes predicting an engine torque profile based on current and future engine operating conditions. The method then models a compressor outlet temperature profile and reduces engine torque output to limit overheating of the compressor outlet.

In a control device of an internal combustion engine, an atmospheric pressure estimation portion includes an effective opening area calculation portion calculating an effective opening area corresponding to a throttle opening, a throttle opening learning value calculation portion calculating a learning value in a relation of the effective opening area and the throttle opening, an error variation calculation portion calculating an error variation from an error from the corrected learning value, a variation range determination portion determining whether the error variation is within a predetermined range, an atmospheric pressure estimated value update portion updating an atmospheric pressure estimated value, and a target throttle opening calculation portion calculating a target throttle opening using the updated atmospheric pressure estimated value. The throttle opening is controlled to be the target throttle opening. An exact atmospheric pressure can be thus estimated even in the presence of a variation in throttle machine difference.

A method for diagnosing a waste gate valve malfunction in a power generation system is presented. The method includes determining an actual pressure differential across a throttle valve. The method further includes determining an estimated pressure differential across the throttle valve based on one or more first operating parameters of the power generation system. Furthermore, the method includes determining an absolute difference between the actual pressure differential and the estimated pressure differential. Moreover, the method also includes comparing the absolute difference with a threshold value and if the absolute difference is greater than the threshold value, determining an operating condition of the throttle valve. Additionally, the method includes determining whether the waste gate valve has malfunctioned based on the determined operating condition of the throttle valve. An engine controller and a power generation system employing the method are also presented.