Abstract:
An actuator control apparatus is provided, capable of causing a state value which changes according to the action of an actuator to match a prescribed target value. A synchronizing mechanism is modeled as the collision of an inertial system object and an elastic system object, and taking as a state amount the deviation between the actual position (Psc) of a coupling sleeve and the target position (Psc_cmd), a computation coefficient (VPOLE) of a switching function used in sliding mode control which takes the state amount as a variable is, in a first process until the coupling sleeve makes contact with a synchronizer ring, set according to the actual position (Psc) of the coupling sleeve, and in a process until the coupling sleeve engages a synchronized gear, is set such that the pressing force of the coupling sleeve matches a target pressing force.
Abstract:
A target value Vtgt for an output Vout of an O2 sensor 8 (an exhaust gas sensor) disposed downstream of a catalytic converter 4 is set variably depending on a temperature TO2 of an active element 10 of the O2 sensor 8 by a target value setting unit 18, and the air-fuel ratio of an exhaust gas is controlled by an air-fuel ratio control unit 17 to converge the output Vout to the target value Vtgt. An exhaust gas temperature Tgd is estimated by an exhaust temperature observer 19, and the temperature TO2 of the active element 10 is sequentially estimated by an element temperature observer 20 using the estimated value of the exhaust gas temperature Tgd. A heater 13 of the O2 sensor 8 is controlled by a heater controller 22 to keep the temperature TO2 of the active element 10 at a predetermined target value R. The air-fuel ratio is thus controlled to maintain a desired exhaust gas purifying capability of the catalytic converter irrespective of the temperature of the active element of the exhaust gas sensor.
Abstract:
A method of calculating the amount of work done by an internal combustion engine, which is capable of calculating a work amount parameter indicative of the amount of work done with accuracy while compensating for a phase delay in in-cylinder pressure data caused e.g. by a filtering process performed thereon. The method calculates the work amount parameter Pmi indicative of the amount of work done by the engine 3 including a combustion chamber 3b, as follows: Pressure in the combustion chamber 3b is detected to obtain in-cylinder pressure data P indicative of the detected pressure. Volume data V indicative of a state of change in volume of the combustion chamber 3b is obtained. The obtained volume data V is subjected to a first predetermined filtering process. The work amount parameter Pmi is calculated based on the detected in-cylinder pressure data P, and the volume data filtered value VF obtained by subjecting the volume data V to the first filtering process.
Abstract:
A cam phase control system for an internal combustion engine, which is capable of suppressing deviation of the cam phase which is caused by a sudden change in the engine speed due to the structure of a variable cam phase mechanism, thereby securing excellent controllability and high control accuracy. The coma phase control system of the engine comprise an ECU and an electromagnetic variable cam phase mechanism. The ECU calculates an SLD control input for causing the cam phase to converge to a target cam phase by equations (1) to (6), calculates a gain-adjusted value by modulating the SLD control input by equations (20) to (25), calculates a correction value according to the engine speed NE, and calculates a control input for controlling the variable cam phase mechanism by correcting the gain-adjusted value by the correction value.
Abstract:
A sensor temperature control means (18) for controlling the temperature of an active element (10) of an exhaust gas sensor (O2 sensor) (8) disposed in an exhaust passage (3) estimates the temperatures of the active element (10) and a heater (13) based on an element temperature model which is representative of a temperature change of the active element due to heat transfer between the active element (10) and the heater (13) which heats the active element and heat transfer between the active element (10) and an exhaust gas, and a heater temperature model which is representative of a temperature change of the heater due to heat transfer between the active element (10) and the heater (13) and the supply of electric power to the heater (13), and controls the heater (13) to equalize the temperature of the active element (10) or the heater (13) with a predetermined target temperature using estimated values of the temperatures. It is possible to accurately estimate the temperature of the active element (10) of the exhaust gas sensor (8) or the heater (13), and control the temperature of the active element (10) of the exhaust gas sensor (8) stably at a desired temperature using an estimated value of the temperature.
Abstract:
The invention provides a control apparatus comprising a controller for determining a manipulated variable for manipulating a controlled object so that an output of the controlled object converges to a desired value and a modulator for modulating the manipulated variable by using one of a delta-sigma modulation algorithm, a sigma-delta modulation algorithm and a delta modulation algorithm to generate a modulated signal to be applied to the controlled object. The modulator generates the modulated signal so that a center value of an amplitude of the modulated signal follows a change of the manipulated variable. Thus, the modulated signal in which the manipulated variable is reflected without any loss can be generated even when the manipulated variable changes.
Abstract:
An apparatus for detecting a failure of an exhaust gas sensor disposed downstream of a catalyst converter in an exhaust manifold is provided. The apparatus comprises a control unit. The control unit determines a ratio between an amplitude value of a first output of the exhaust gas sensor and an amplitude value of a second output of an air-fuel ratio sensor. The air fuel ratio sensor disposed upstream of the catalyst converter. The control unit detects a failure of the exhaust gas sensor based on the ratio. In one embodiment, a statistical process using a successive least squares method is applied to the ratio. The control unit detects a failure of the exhaust gas sensor based on the statistically processed ratio. In another embodiment, the statistical process is applied to both the output of the exhaust gas sensor and the output of the air-fuel ratio sensor. The control unit detects a failure of the exhaust gas sensor based on a ratio between the statistically processed outputs of the exhaust gas sensor and the air-fuel ratio sensor.
Abstract:
There is provided a control system for an internal combustion engine, which is capable of meeting a driver's demand of torque, and achieving high combustion efficiency and high emission-reducing performance by a three-way catalyst in lean-burn operation in a compatible manner. The control system sets a control amount indicative of either an oxygen mass supplied to a combustion chamber or a fuel injection amount such that oxygen concentration in exhaust gases becomes equal to a value corresponding to stoichiometric combustion. A target value corresponding to a demanded torque is set based on detected engine operating conditions. A degree of opening of a main throttle valve and a degree of opening of a sub-throttle valve in a passage by passing an intake passage equipped with a nitrogen-enriching device are controlled such that the control amount becomes equal to the set target value.
Abstract:
An air-fuel ratio control system for an internal combustion engine is provided which is capable of appropriately and promptly correcting variation in the air-fuel ratio of a mixture between cylinders and realizing a very robust air-fuel ratio control, even with a complicated exhaust system layout. The ECU of the system for control of the air-fuel ratio of a mixture supplied to first to fourth cylinders determines a feedback correction coefficient, calculates a cylinder-by-cylinder variation coefficient indicative of variation in air-fuel ratio between the cylinders, based on a model parameter of a model having the input of the feedback correction coefficient thereto and the output of the detected air-fuel ratio, identifies the model parameter, corrects a basic fuel injection amount such that the cylinder-by-cylinder variation parameter converges to a moving average value thereof, thereby calculating a cylinder-by-cylinder final fuel injection amount.
Abstract:
Exhaust gas sensors or air-fuel ratio sensors for generating outputs depending on the concentration of HC are disposed respectively upstream and downstream of an HC adsorbent in an exhaust passage. When an exhaust gas emitted from an internal combustion engine is supplied to the exhaust passage to allow the HC adsorbent to adsorb HC in the exhaust gas, an amount of HC adsorbed by the HC adsorbent per unit time is determined based on the difference between outputs from the exhaust gas sensors. A deteriorated state of the HC adsorbent is evaluated by comparing the determined adsorbed amount of HC and its integrated value with a threshold set depending on a temperature or the like of the HC adsorbent.