Abstract: The present invention provides a catalyst temperature control device to control a temperature of a catalyst which influences emission performance of an internal combustion engine. A plurality of temperature measurement points are disposed continuously or dispersedly at least in a flow path direction inside the catalyst. The temperature measurement points can include actual measurement points where temperature sensors are disposed, and virtual measurement points where temperature sensors are not disposed. A control point is selected from the plurality of temperature measurement points in accordance with operation conditions of the internal combustion engine, and a target value of the temperature of the catalyst is set.

Abstract: An apparatus controls an internal combustion engine provided with an EGR device having an EGR passage and an EGR valve that is provided in the EGR passage and can adjust an EGR amount. This apparatus includes a controller that estimates state parameters of the internal combustion engine that affect the behavior of the EGR gas within a predetermined period of time; sets constraints on the EGR amount within the predetermined period on the basis of an approximated dynamics obtained by approximating a true dynamics, which is a transition of the EGR amount within the predetermined period, so that approximated values do not exceed the true dynamics; determines a target value of the EGR amount according to the estimated state parameters within a range of the EGR amount on which the constraints that have been set; and controls the EGR valve so that the EGR amount becomes the determined target value.

Abstract: A control apparatus of an internal combustion engine capable of appropriately reflecting various requests relating to the performance of the internal combustion engine. Specifically, the control device of the internal combustion engine acquires various requests relating to the performance of the internal combustion engine, and sets restricted ranges of the value of the control variable in accordance with the details of the requests. At this moment, the control device temporally changes the set restricted ranges for specific requests associated with the time integral value of the control variable rather than the instantaneous value of the control variable. Subsequently, the control device determines a final restricted range on the basis of the overlap between the restricted ranges set for each request, and determines the target value of the control variable in the final restricted range.

Abstract: A control device used for an internal combustion engine and capable of determining an actuator operation amount is provided. The control device includes a computation element that uses engine status amounts to compute the actuator operation amount. The computation element uses a model that includes a plurality of submodels arranged in a hierarchical sequence. The computation element computes the actuator operation amount by using a parameter calculated by the lowest level submodel and changes the number of higher-level submodels to be used in combination with the lowest level submodel in accordance with the operation status of the internal combustion engine.

Abstract: A exhaust catalyst temperature estimating apparatus is provided for estimating a exhaust catalyst temperature of a exhaust catalyst in which a catalyst is loaded on a support and arranged in an exhaust system of an internal combustion engine. The exhaust catalyst temperature estimating apparatus estimates the exhaust catalyst temperature using a first model formula to calculate a current exhaust catalyst temperature of the exhaust catalyst based on a parameter corresponding to a current exhaust gas status. The first model formula is empirically determined such that a exhaust catalyst temperature that excludes heat generated by a chemical reaction is calculated for the parameter by using the support prior to being loaded with the catalyst, or is a physical formula of the support prior to being loaded with the catalyst such that a exhaust catalyst temperature excludes heat generated by a chemical reaction is calculated for the parameter.

Abstract: A control device used for an internal combustion engine and capable of determining an actuator operation amount is provided. The control device includes a computation element that uses engine status amounts to compute the actuator operation amount. The computation element uses a model that includes a plurality of submodels arranged in a hierarchical sequence. The computation element computes the actuator operation amount by using a parameter calculated by the lowest level submodel and changes the number of higher-level submodels to be used in combination with the lowest level submodel in accordance with the operation status of the internal combustion engine.

Abstract: A control apparatus of an internal combustion engine capable of appropriately reflecting various requests relating to the performance of the internal combustion engine. Specifically, the control device of the internal combustion engine acquires various requests relating to the performance of the internal combustion engine, and sets restricted ranges of the value of the control variable in accordance with the details of the requests. At this moment, the control device temporally changes the set restricted ranges for specific requests associated with the time integral value of the control variable rather than the instantaneous value of the control variable. Subsequently, the control device determines a final restricted range on the basis of the overlap between the restricted ranges set for each request, and determines the target value of the control variable in the final restricted range.

Abstract: The present invention has an object to provide a catalyst temperature control device that can properly control a temperature of a catalyst which influences an emission performance of an internal combustion engine. A plurality of temperature measurement points are disposed continuously or dispersedly at least in a flow path direction inside the catalyst. The temperature measurement points can include not only actual measurement points where temperature sensors are disposed, but also virtual measurement points where temperature sensors are not disposed. A control point is selected from the plurality of temperature measurement points in accordance with operation conditions of the internal combustion engine, and a target value of the temperature of the catalyst is set. As a temperature at the selected control point, when the control point is the actual measurement point, an actual measurement value by the temperature sensor can be used.

Abstract: A exhaust catalyst temperature estimating apparatus is provided for estimating a exhaust catalyst temperature of a exhaust catalyst in which a catalyst is loaded on a support and arranged in an exhaust system of an internal combustion engine. The exhaust catalyst temperature estimating apparatus estimates the exhaust catalyst temperature using a first model formula to calculate a current exhaust catalyst temperature of the exhaust catalyst based on a parameter corresponding to a current exhaust gas status. The first model formula is empirically determined such that a exhaust catalyst temperature that excludes heat generated by a chemical reaction is calculated for the parameter by using the support prior to being loaded with the catalyst, or is a physical formula of the support prior to being loaded with the catalyst such that a exhaust catalyst temperature excludes heat generated by a chemical reaction is calculated for the parameter.

Abstract: Disclosed is a control device that is used for an internal combustion engine and capable of making various requests concerning the performance of the internal combustion engine be reflected in a target control amount value while the requests need not be expressed in the form of a requested control amount value. The control device acquires various requests concerning the performance of the internal combustion engine and sets a request-specific constraint on a control amount value. More specifically, the control device expresses constraints to be set for control amount values as a set of constraint index values assigned to individual control amount values, and varies the distribution of the constraint index values assigned to the control amount values in accordance with the type of a request. Next, the control device integrates, for each control amount value, the constraint index values assigned to individual requests with respect to each control amount value.

Abstract: A control device for an internal combustion engine which, at cold starting, enables an ignition timing retard control for warm-up of a catalyst device and a speed feedback control by means of ignition timing for converging an engine speed to a target speed includes a function for comparing a final ignition timing with a retard lower limit value, and a function for changing the target speed based upon the result of the comparing. When the final ignition timing reaches the retard lower limit value, the target speed is increased by a predetermined speed and when a difference between the final ignition timing and the retard lower limit value exceeds a predetermined angle on an advance side, the target speed is decreased by a predetermined speed. In this way, at cold starting, the engine speed is early converged to the target speed while restricting rotational variations and early warm-up of a catalyst device can be certainly realized.

Abstract: Disclosed are a control device and a control method that are used with an internal combustion engine in which the air-fuel ratio in the vicinity of an ignition plug differs from the overall air-fuel ratio in a cylinder, and capable of properly fulfilling demands concerning various capabilities of the internal combustion engine by accurately reflecting each of the demands in the operation of each actuator. Three physical quantities, namely, a torque, an efficiency, and an air-fuel ratio, are used as controlled variables for the internal combustion engine. Target values for the controlled variables are then set by integrating at least some of demands concerning a capability of the internal combustion engine into the three physical quantities.

Abstract: A control device for an internal combustion engine which, at cold starting, enables an ignition timing retard control for warm-up of a catalyst device and a speed feedback control by means of ignition timing for converging an engine speed to a target speed includes a function for comparing a final ignition timing with a retard lower limit value, and a function for changing the target speed based upon the result of the comparing. When the final ignition timing reaches the retard lower limit value, the target speed is increased by a predetermined speed and when a difference between the final ignition timing and the retard lower limit value exceeds a predetermined angle on an advance side, the target speed is decreased by a predetermined speed. In this way, at cold starting, the engine speed is early converged to the target speed while restricting rotational variations and early warm-up of a catalyst device can be certainly realized.

Abstract: A controller (6) for an internal combustion engine includes: a calculation section (5) for calculating an angular acceleration or an angular velocity; an operational status-determining section (5, 6) for determining an operational status based on the angular acceleration or the angular velocity; a gain-setting section (6, 3a) for setting a gain of torque based on feedback control; and a control section (6) for controlling the gain-setting section so that, when the operational status is a first operational status, the gain-setting section uses the angular acceleration as input data to set the gain (i), and when the operational status is a second operational status, the gain-setting section uses the angular velocity as input data to set the gain (ii).

Abstract: In a speed transition period from when an internal combustion engine is started to when an engine speed settles down to a certain speed, a compression top dead center of a cylinder first operating is set as a reference crank angle and compression top dead centers of the cylinders arriving successively after said reference crank angle in the speed transition period are set as judgment use crank angles. Reference crank angle advancing times are detected and stored in advance, wherein the reference crank angle advancing times are crank angle advancing times when a reference fuel is used, and the crank angle advancing times are times required for the crank angle to advance from the reference crank angle to the judgment use crank angles. The actual crank angle advancing times are detected.

Abstract: A controller (6) for an internal combustion engine includes: a calculation section (5) for calculating an angular acceleration or an angular velocity; an operational status-determining section (5, 6) for determining an operational status based on the angular acceleration or the angular velocity; a gain-setting section (6, 3a) for setting a gain of torque based on feedback control; and a control section (6) for controlling the gain-setting section so that, when the operational status is a first operational status, the gain-setting section uses the angular acceleration as input data to set the gain (i), and when the operational status is a second operational status, the gain-setting section uses the angular velocity as input data to set the gain (ii).

Abstract: The fuel injection amounts into each cylinder are set on the assumption that a heavy fuel will be injected during the engine starting process, and a specific torque is allowed to be generated by combustion in a specific cylinder when a fuel with a specific property between those of the heaviest fuel and the lightest fuel is injected thereinto. When the torque generated in the specific cylinder is in a range at or around the specific torque, the property level of fuel to be injected during the engine starting process is determined to be in a level range at or around the specific property. When the torque generated in the specific cylinder is higher than the range around the specific torque, the property level is determined to be in a level range on the light fuel side of the level range around the specific property.

Abstract: The fuel injection amounts into each cylinder are set on the assumption that a heavy fuel will be injected during the engine starting process, and a specific torque is allowed to be generated by combustion in a specific cylinder when a fuel with a specific property between those of the heaviest fuel and the lightest fuel is injected thereinto. When the torque generated in the specific cylinder is in a range at or around the specific torque, the property level of fuel to be injected during the engine starting process is determined to be in a level range at or around the specific property. When the torque generated in the specific cylinder is higher than the range around the specific torque, the property level is determined to be in a level range on the light fuel side of the level range around the specific property.

Abstract: In a speed transition period from when an internal combustion engine is started to when an engine speed settles down to a certain speed, a compression top dead center of a cylinder first operating is set as a reference crank angle and compression top dead centers of the cylinders arriving successively after said reference crank angle in the speed transition period are set as judgment use crank angles. Reference crank angle advancing times are detected and stored in advance, wherein the reference crank angle advancing times are crank angle advancing times when a reference fuel is used, and the crank angle advancing times are times required for the crank angle to advance from the reference crank angle to the judgment use crank angles. The actual crank angle advancing times are detected.

Abstract: An operating condition value is acquired at the time of internal combustion engine startup. If the acquired condition value is one of a plurality of reference condition values for which optimum values are defined, the optimum value for the reference condition value is set as a fuel injection amount. If, on the other hand, the acquired condition value is other than the reference condition values, an interpolated value, which is interpolation-calculated by using the relationship between the reference condition values and optimum values, is set as a fuel injection amount. The angular acceleration for fuel injection according to the interpolated value, which is a physical quantity related to the operating performance of an internal combustion engine, is then determined to correct the interpolated value in accordance with the difference between the actual angular acceleration and target angular acceleration.