Systems are provided for detecting a change in performance of an engine component. In one example, a system includes a first pressure sensor of a first exhaust manifold coupled to a first subset of cylinders of an engine, a second pressure sensor of a second exhaust manifold coupled to a second subset of cylinders of the engine, a passage coupling the first exhaust manifold to an intake manifold, and a controller configured to detect a change in performance of any cylinder of the engine based on frequency content from the first pressure sensor and from the second pressure sensor during both a first mode where no exhaust gas from the first exhaust manifold is provided to the intake manifold, and during a second mode where all exhaust gas from the first exhaust manifold is provided to the intake manifold, and adjust an operating parameter responsive to the change in performance.

A diesel engine, in particular a high-power diesel engine, which has a variable valve train including an adjusting unit for adjusting a valve opening time, a valve lift, a camshaft phase position and/or a valve steering, and a control or regulating unit for controlling the adjusting unit. The control and/or regulating unit includes at least one operational mode provided for starting the engine when the engine is at a low temperature, in which the control and/or regulating unit is provided to adjust the valve opening time, at least during a preliminary phase for at least one inlet valve, which overlaps at least with one compression stroke of an associated cylinder, and to interrupt an injection of fuel at least into the cylinder associated with the inlet valve. The invention also relates to a method for starting such a diesel engine.

An apparatus for controlling an EGR valve, includes: a measurement unit to measure at least one operation condition of an engine system; a fresh air amount setting unit to set a target amount of fresh air based on the operation condition; a fresh air amount sensor to measure a current amount of fresh air introduced through an intake line; a control calculation unit to set a signal for controlling an opening degree of the EGR valve so that the current amount of fresh air follows the target amount of fresh air; and an identifier to simulate an input and an output of the engine system, and output engine system input-output sensitivity which is a ratio of a change rate of the current amount of fresh air to a change rate of the opening degree of the EGR valve.

A gas engine heat pump and a method of operating the same are provided. According to an embodiment of the present disclosure, the gas engine heat pump includes: an engine for burning a mixture of air and fuel; an exhaust gas compressor for compressing exhaust gases coming from the engine; a buffer tank for storing the exhaust gases compressed by the exhaust gas compressor; an exhaust gas valve disposed between the buffer tank and an intake manifold of the engine; an exhaust gas spray nozzle for spraying the exhaust gases stored in the buffer tank into a cylinder of the engine; an exhaust gas sensor for acquiring information on the exhaust gases coming from the engine; and a controller, wherein the controller controls the operation of at least one of the exhaust gas valve and the exhaust gas spray nozzle, based on the information on the exhaust gases acquired by the exhaust gas sensor. Other various embodiments are possible.

An engine system includes an intake passage, a non-deactivation exhaust passage, a second exhaust manifold, a first turbocharger including a first turbine rotated by exhaust gas flowing via the first exhaust manifold, a second turbocharger including a second turbine rotated by exhaust gas flowing via the second exhaust manifold, an exhaust outlet, a main intake circulation passage in communication with the intake passage via a compressor of the first turbocharger such that supercharging air is supplied to the intake passage, a sub intake circulation passage in communication with the main intake circulation passage via a compressor of the second turbocharger such that supercharging air is supplied to the main intake circulation passage, and a deactivation valve disposed on the sub intake circulation passage between the compressor of the second turbocharger and the main intake circulation passage so as to selectively open/close the sub intake circulation passage.

Methods and systems are provided for controlling a temperature of gases within a heat exchanger, a ratio of gases output by the heat exchanger, and selectively charging/discharging gases from the heat exchanger to one or both of an intake system or an exhaust system. In one example, a method may include controlling operation of an energy recovery device coupled to the heat exchanger in response to engine operating conditions, and increasing or decreasing flow of exhaust gas and/or compressed intake air into the heat exchanger in response to energy recovery device output.

An object is to supply fresh air and EGR gas into a cylinder in good balance according to the required load in a naturally aspirated gasoline engine. When the operation state of the engine falls in a low load range, a control apparatus adjusts the degree of opening of the second throttle while keeping the first throttle fully open and controls EGR gas quantity by adjusting the degree of opening of the EGR valve. When the operation state falls in a middle load range, the apparatus controls EGR gas quantity by adjusting the degree of opening of the first throttle while keeping the EGR valve fully open. When the operation state falls in a high load range, the apparatus adjusts the degree of opening of the first throttle while keeping the second throttle fully open and controls EGR gas quantity by adjusting the degree of opening of the EGR valve.

A method of controlling exhaust gas recirculation (EGR) for controlling recirculation of exhaust gas discharged from a combustion chamber of an engine includes: a data obtaining operation of obtaining data about an engine state and a gas supply state; a current EGR rate calculating operation of calculating a current EGR rate of supply gas based on the data; a demand EGR rate setting operation of setting a demand EGR rate matched with the data in a pre-made target EGR rate map; an error calculating operation of calculating a difference between the demand EGR rate and the current EGR rate; and a control operation of making the current EGR rate follow the demand EGR rate by changing a recirculation rate of the exhaust gas by adjusting an inhalation side pressure of the supply gas according to the difference.

The invention relates to a control device for an internal combustion engine using the center-of-gravity position of a heat generation rate for combustion control. This control device controls the center-of-gravity position of a heat generation rate to correspond to a reference position in a case where an engine cooling water temperature is equal to or higher than a reference cooling water temperature and controls the center-of-gravity position of a heat generation rate to correspond to a crank angle further on an advance side than the reference position in a case where the engine cooling water temperature is lower than the reference cooling water temperature.

A requesting module generates a first torque request for an engine based on driver input. A conversion module converts the first torque request into a second torque request. A model predictive control (MPC) module determines a current set of target values based on the second torque request, a model of the engine, a tableau matrix, and a basic solution matrix. The MPC module: initializes the basic solution matrix to a predetermined matrix that is dual feasible; selectively iteratively updates the basic solution matrix and columns of the tableau matrix; determines changes for the target values, respectively, based on entries of the basic solution matrix resulting from the selective iterative updating; and determines the current set of target values by summing the changes with a last set of target values, respectively. An actuator module controls an engine actuator based on a first one of the current set of target values.