An internal combustion engine control device 110 includes a mass flux calculation unit F2, an opening area calculation unit F3, an effective opening area calculation unit F4, and a passing gas flow rate calculation unit F5. The mass flux calculation unit F2 calculates a mass flux MF of gas passing through a throttle valve 125 based on an upstream gas temperature Tu, an upstream gas pressure Pu, and a downstream gas pressure Pd of the throttle valve 125. The opening area calculation unit F3 calculates an opening area A of the throttle valve 125 based on an opening degree θ of the throttle valve 125. The effective opening area calculation unit F4 calculates an effective opening area EA of the throttle valve 125 based on the upstream gas pressure Pu, the downstream gas pressure Pd, the opening degree θ, and the opening area A. The passing gas flow rate calculation unit F5 calculates a gas flow rate GF passing through the throttle valve 125 based on the mass flux MF and the effective opening area EA.

A control device predicts whether temporary reduction occurs to a charging efficiency of fresh air in an in-cylinder gas by an influence of an EGR rate of the in-cylinder gas, which increases later than increase of a charging efficiency of the in-cylinder gas, if a first arithmetic operation is applied to calculating a target throttle opening degree based on a target charging efficiency which is increasing, in a case of shifting to an acceleration operation, by using a prediction model expressing dynamic characteristics of an internal combustion engine. When it is predicted that temporary reduction occurs to the charging efficiency of the fresh air, the control device calculates the target throttle opening degree by a second arithmetic operation by which an increase speed of a throttle opening degree is restrained more than by the first arithmetic operation, instead of calculating the target throttle opening degree by the first arithmetic operation.

A power-based control system and method for an engine comprising a turbocharger involve obtaining a set of parameters that each affect exhaust gas energy and using the set of parameters to (i) determine a target mass flow into the engine and a target boost for the turbocharger to achieve a torque request, (ii) determine a target power for a compressor of the turbocharger to achieve the target engine mass flow and the target turbocharger boost, (iii) determine a target pressure ratio and a target mass exhaust flow for the turbine of the turbocharger to achieve a target turbine power equal to the target compressor power, and (iv) determine a target position of the wastegate valve to achieve the target turbine pressure ratio and mass exhaust flow, and commanding a wastegate valve to the target position.

The present invention discloses a method of introducing fuel into a diesel engine for combustion within the engine. A natural gas in liquid form is injected into the engine for combustion therein with diesel fuel so as to maintain a natural gas concentration derived from the liquid in the range of greater than 0.6% to 3.0% of air intake by volume of natural gas. Suitable gases include natural gas, methane or substantially methane gas mixtures and substitute natural gas such as propane air mixtures providing a mixture with similar combustion properties to methane/natural gas.

An air intake amount measurement device 200 includes an intake distributor 3 distributing intake air CYL to cylinders 11, 12, 13, and 14, a temperature detector 202 detecting a temperature Ti of the intake air CYL, a pressure detector 201 for detecting a pressure Pi of intake air CL, and a computing unit 100 that computes an air intake amount mfcyl of the intake air CYL on the basis of the temperature Ti transmitted from the temperature detector 202 and the pressure Pi transmitted from the pressure detector 201. The temperature detector 202 detects the temperature Ti of the intake air CYL at a region W spanning, out of an inside of the intake distributor 3, a first branch portion 31 and a second branch portion 32.

A fault detection device includes a wastegate valve, a control unit, a working gas amount computation section, and a determination section. The control unit obtains a rotational speed of an engine, a boost pressure, and an intake air temperature. The working gas amount computation section computes a computed value of a mass flow rate of working gas in the engine by using the rotational speed, the boost pressure, and the intake air temperature. The determination section determines that the wastegate valve has a fault when the computed value is not a normal value.

A control device for an internal combustion engine, which can accurately estimate an intake air amount introduced from an intake system into an internal combustion engine, is provided. The control device calculates the change amount of an air amount in an upstream section upstream of a throttle valve of the intake system based on the pressure and temperature of air in the upstream section; calculates a throttle passage air amount flowing out to an intake manifold, which is a section downstream of the throttle valve, based on the change amount and an introduced air amount flowing into a supercharger; and calculates the intake air amount based on the throttle passage air amount.

According to the invention, a method and system for estimating fresh air flow into a turbocharged engine (105) is provided. A controller (109) arranged to determine an actual fresh air mass flow in subsequent time frames by measuring, in an actual time frame, a pressure drop over a compressor (101) and using a first calculated fresh air mass flow as a starting value for deriving a second fresh air mass flow in said time frame from a compressor model using the measured pressure drop and a compressor rotational speed. In a previous time frame, before said actual time frame, a pressure drop is measured over an air treatment device. A pressure drop is estimated over the air treatment device (103, 104, 106, 108) using the second fresh air mass flow and an estimated flow resistance of the air treatment device. Subsequently, the second fresh air mass flow is corrected by comparing the estimated pressure drop with the measured pressure drop over the air treatment device and using the corrected second fresh air mass flow as an actual fresh air mass flow in said time frame.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias.

Based on entry/exit pressures of a compressor detected by atmospheric/boost pressure sensors, a pressure ratio of compressor is calculated. Based on mass flow rate and entry temperature of intake air detected by intake air flow-rate/temperature sensors and entry pressure, a volumetric flow rate of intake air is calculated in environmental condition at a detection time using gas state equation, and is corrected into a volumetric flow rate under standard environmental condition thorough multiplication by a corrective coefficient based on entry temperature of intake air. Based on the corrected value and the calculated pressure ratio, a rotational frequency of compressor under standard environmental condition is read out in light of operating characteristic diagram for the compressor. Read-out rotational frequency is corrected into actual rotational frequency of the compressor through multiplication by a corrective coefficient based on entry temperature of intake air, which is determined as rotational frequency of turbocharger.