A control apparatus of an internal combustion engine having an injector which directly injects fuel into a combustion chamber of a cylinder and a spark plug which ignites an air-fuel mixture containing the fuel injected by the injector includes an air-fuel ratio acquisition unit acquiring an air-fuel ratio of the air-fuel mixture in the combustion chamber, a nitrogen oxide concentration acquisition unit acquiring a concentration of nitrogen oxide in a combustion gas exhausted from the internal combustion engine, and a stratification level estimation unit estimating a level of stratification as a measure of level of distribution of the air-fuel mixture at a predetermined air-fuel ratio or below in a vicinity of the spark plug. The stratification level estimation unit estimates the level of stratification according to the air-fuel ratio acquired by the air-fuel ratio acquisition unit and the concentration of nitrogen oxide acquired by the nitrogen oxide concentration acquisition unit.

A method and system are provided with which it is possible to detect non-firing and untimely firing events in internal combustion and, if necessary, the temperature of the gas in the exhaust gas pipe. This is performed in general by measuring the speed of sound and determining the phase angle between the sender and receiver either arranged on different sides of the exhaust gas pipe or on the same side of the exhaust gas pipe. The receiver, depending on the measurement principle, can include one, two, or in special applications three receivers. Additionally, if necessary, it is possible to suppress the structure-borne sound influence on a speed of sound measurement with low cost and high stability.

A heating system includes at least one electric heater disposed within a fluid flow system and a control device that is configured to determine a temperature of the at least one electric heater based on a model, at least one fluid flow system input, and at least one heater input. The at least one heater input includes at least one physical characteristic of the heating system, the at least one physical characteristic includes at least one of a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, a conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, and combinations thereof. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

A method for diagnosing a plurality of lambda sensors which are arranged upstream of an exhaust gas catalytic converter in a plurality of exhaust gas banks of a multi-flow exhaust gas system of an internal combustion engine. An opposite lambda offset of the lambda sensors is identified (54) when a difference (ΔT) between a measured exhaust gas temperature (T.sub.measure) and a modeled exhaust gas temperature (T.sub.mod) downstream of the exhaust gas catalytic converter overshoots a threshold value (S).

A method for diagnosing a heating element of an exhaust gas sensor of an internal combustion engine. The exhaust gas sensor includes a temperature measurement device. A modeled temperature at the point of the exhaust gas sensor is continuously ascertained with the aid of a temperature model. The temperature of the exhaust gas sensor is increased by a heating process. The diagnosis of the heating element of the exhaust gas sensor is provided as the result an enable condition. Upon enablement of the diagnosis, a temperature difference between the modeled temperature of the exhaust gas sensor and the measured temperature of the exhaust gas sensor are ascertained. The heating element of the exhaust gas sensor is recognized as defective when the ascertained temperature difference exceeds a predefinable temperature threshold value.

A control device of an exhaust sensor comprises a heater control part configured to set a target temperature of an electrochemical cell and control a heater so that a temperature of the electrochemical cell becomes the target temperature, and a judging part configured to judge whether a water repellency of a protective layer is falling when the heater control part sets the target temperature to a temperature of a lowest temperature at which a Leidenfrost phenomenon occurs at an outer surface of the protective layer or more. The heater control part is configured to rise the target temperature when the judging part judges that the water repellency of the protective layer is falling.

A heating system includes at least one electric heater disposed within the fluid flow system. A control device includes a microprocessor and is configured to determine a temperature of the at least one electric heater based on a model and at least one input from the fluid flow system. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

A device for measuring temperature of a turbine wheel in a turbocharger includes: a guide that passes infrared ray generated from the turbine wheel and includes a coolant path; a protection unit that protects an optical head which senses the infrared ray; and a signal processing unit that measures a temperature of the turbine wheel by processing a signal corresponding to the sensed infrared ray.

The present invention relates to a control device and a control method for an internal combustion engine equipped with a variable compression ratio mechanism. The control device sets an air charging efficiency as an engine load equivalent value and performs setting of a determination value used for misfire diagnosis, setting of an ignition timing, an estimation of a catalyst temperature, or the like. In the control device, when a compression ratio is higher than the basic compression ratio, and the theoretical thermal efficiency is high, the air charging efficiency is corrected to be increased, to perform the control on the basis of the corrected air charging efficiency. Furthermore, in a torque control that sets a target air charging efficiency on the basis of a torque command value, when the compression ratio is higher than the basic compression ratio, the target air charging efficiency is reduced.

Systems and apparatuses include a circuit structured to receive information indicative of a catalyst health, receive information from a sensor array indicative of a catalyst activity, determine a catalyst health management criteria has been met based on the information, determine a catalyst age based on the information indicative of the catalyst activity and the catalyst health management criteria being met, compare the determined catalyst age to a predetermined age threshold, and provide a notification when the determined catalyst age exceeds the predetermined age threshold.