摘要:
The characteristics of an output of an exhaust gas sensor (5) with respect to an air-fuel ratio of an engine (1) are expressed according to a quadratic function, and the parameters of the quadratic function are sequentially identified according to a sequential identifying algorithm using data of the output of the exhaust gas sensor and data of an output of an air-fuel sensor (4) which detects the air-fuel ratio of the engine. Deterioration evaluating parameters whose values change as the deterioration of a catalytic converter processes are sequentially determined from the identified values of the parameters of the quadratic function, and the deteriorated state of the catalytic converter (3) is evaluated based on the determined deterioration evaluating parameters.
摘要:
An air-fuel control system for use with an internal combustion engine (1) has a catalytic converter (4) disposed in an exhaust system (A) of the engine, for purifying an exhaust gas emitted from the engine, a first exhaust gas sensor (6) disposed in the exhaust system for detecting an air-fuel ratio of the exhaust gas upstream of the catalytic converter, a second exhaust gas sensor (7) disposed in the exhaust system for detecting the concentration of a component of the exhaust gas which has passed through the catalytic converter, downstream of the catalytic converter, and a control unit (8) for controlling an air-fuel ratio of the engine based on outputs from the first exhaust gas sensor and the second exhaust gas sensor. The control unit includes an adaptive sliding mode controller (19) for determining a correction quantity to correct the air-fuel ratio of the engine so as to equalize the concentration of the component of the exhaust gas downstream of the catalytic converter to a predetermined appropriate value, according to an adaptive sliding mode control process based on the output from the second exhaust gas sensor, and a feedback controller (17) for controlling a rate at which fuel is supplied to the engine so as to converge the concentration of the component of the exhaust gas downstream of the catalytic converter toward the predetermined appropriate value, based on the correction quantity and the output from the first exhaust gas sensor (6).
摘要:
An air-fuel control system for use with an internal combustion engine (1) has a catalytic converter (4) in an exhaust system (A) of the engine, for purifying an exhaust gas emitted from the engine, a first exhaust gas sensor (6) in the exhaust system for detecting an air-fuel ratio of the exhaust gas upstream of the catalytic converter, and a second exhaust gas sensor (7) in the exhaust system for detecting the concentration of a component of the exhaust gas which has passed through the catalytic converter, downstream of the catalytic converter. A sliding mode controller (19) determines a correction quantity at a first period to correct the air-fuel ratio of the engine so as to equalize the concentration of the component downstream of the catalytic converter to a predetermined appropriate value, according to a sliding mode control process based on the output from the second exhaust gas sensor. A feedback controller (17) determines a correction quantity at a second period for a rate at which fuel is supplied to the engine so as to converge the concentration of the component downstream of the catalytic converter toward the predetermined appropriate value, based on the correction quantity to correct the air-fuel ratio and the output from the first exhaust gas sensor, and feedback-controls the rate at which fuel is supplied to the engine with the determined correction quantity. The first and second periods are established separately from each other.
摘要:
A control apparatus controls the rotational speed of an internal combustion engine by generating a command value for ignition timing of the internal combustion engine to convert an actual rotational speed of the internal combustion engine to a predetermined target rotational speed according to a feedback control process and controlling the ignition timing based on the generated command value. The feedback control process is carried out by a response designating control process capable of variably designating a rate of reduction of the difference between the actual rotational speed of the internal combustion engine and the target rotational speed with the value of a predetermined parameter in the feedback control process. The value of the predetermined parameter is variably established under a predetermined condition.
摘要:
A control apparatus controls an internal combustion engine by generating a command value for a manipulative quantity of a flow control valve disposed in an intake air passage of an internal combustion engine controllable by the flow control valve, according to a sliding mode control process in order to converge a predetermined control quantity relative to the internal combustion engine to a target value thereof. An object to be controlled by the sliding mode control process is modeled by a discrete system for generating the control quantity from the command value for the manipulative quantity of the flow control valve. The sliding mode control process uses a switching function constructed by a linear function composed of a plurality of time-series data of the difference between the control quantity and the target value. An algorithm for generating the command value for the manipulative quantity of the flow control valve in a predetermined control cycle according to the sliding mode control process is constructed based on the discrete-system model of the object to be controlled and the switching function.