摘要:
An allowable range (adaptive allowable range) for limiting a manipulated variable generated in order to converge the difference between an output from an O2 sensor disposed downstream of a catalytic converter and a target value thereof to “0” is sequentially updated depending on how the manipulated variable deviates from the allowable range.
摘要:
A plant control system has a reference value setting unit for variably setting a reference value for an air-fuel ratio to be given to an exhaust system including a catalytic converter, depending on a component based on an adaptive control law of a manipulated variable of the air-fuel ratio generated by a controller according to an adaptive sliding mode control process in order to converge an output of an O2 sensor disposed downstream of the catalytic converter to a target value. The manipulated variable generated by the controller represents the difference between the air-fuel ratio and the reference value, required to converge the output of the O2 sensor to the target value.
摘要:
An object system for generating an output signal of an O2 sensor from a target air-fuel ratio is expressed as a model including a response delay element and a dead time element. Data of identified values of parameters of the model are sequentially generated by an identifier. Data of an estimated value of the output signal of the O2 sensor after a dead time of the object system is sequentially generated by an estimator. The target air-fuel ratio is generated according to an adaptive sliding mode control process performed by a sliding mode controller using the data of the identified and estimated values. The air-fuel ratio of an internal combustion engine is manipulated on the basis of the target air-fuel ratio according to a feed-forward control process.
摘要:
While the amount of intake air introduced into an internal combustion engine is being increased by an intake air quantity control unit, an ignition timing control unit manipulates the ignition timing of the internal combustion engine to converge the rotational speed of the internal combustion engine to a target rotational speed according to a feedback control process (PI control process). The ignition timing control unit has a function to vary the feedback gain of the feedback control process depending on the ignition timing, such that the feedback gain is smaller as the ignition timing being manipulated is more retarded.
摘要:
A plant control system has a reference value setting unit for variably setting a reference value for an air-fuel ratio to be given to an exhaust system including a catalytic converter, depending on a component based on an adaptive control law of a manipulated variable of the air-fuel ratio generated by a controller according to an adaptive sliding mode control process in order to converge an output of an O2 sensor disposed downstream of the catalytic converter to a target value. The plant control system also has an estimator for estimating the difference between an output of the O2 sensor after the dead time of the exhaust system and a target value therefor, using the difference between the set reference value and a detected value of the air-fuel ratio, and giving the estimated difference to the controller.
摘要:
An apparatus for controlling an internal combustion engine has an amount-of-intake-air control unit for generating a command value for the opening of a flow control valve in an intake passage of the engine, which emits exhaust gases through a catalytic converter, so as to increase an amount of intake air introduced into a combustion chamber by a predetermined quantity greater when the engine operates in an idling mode after it has started to operate than when the engine operates in a normal idling mode, and controlling the opening of the flow control valve based on the generated command value, and an ignition timing control unit for controlling the ignition timing according to a feedback control process to correct the ignition timing so as to be retarded in order to converge the rotational speed of the engine to a predetermined target rotational speed while the amount of intake air is being increased. The amount-of-intake-air control unit successively acquires amount-of-heat data representing the amount of heat energy actually given to the catalytic converter by exhaust gases flowing into said catalytic converter while the amount of intake air is being increased, and corrects the command value for the opening of said flow control valve according to a feedback control process in order to converge the acquired amount-of-heat data to a predetermined target value representing an amount of heat energy to be given to said catalytic converter.
摘要:
An adsorbent state determining apparatus is provided for accurately determining the state of an adsorbent including a deterioration as well as for allowing for recovery of the adsorbent if its adsorbent performance can be restored. The adsorbent state determining apparatus determines the state of an adsorbent for adsorbing hydrocarbons contained in exhaust gases. An upstream and a downstream temperature sensor are provided at upstream and downstream locations of the adsorbent in an exhaust system for detecting temperatures of exhaust gases upstream and downstream of the adsorbent. An engine water temperature sensor detects an operating state of the engine. An ECU estimates the temperature of the exhaust gas which should be detected downstream of the adsorbent during adsorption of the adsorbent based on the upstream temperature detected by the upstream temperature sensor and an engine water temperature of the engine detected by the engine water temperature sensor. The ECU then compares the estimated downstream temperature with the detected downstream temperature detected by the downstream temperature sensor during adsorption of the adsorbent to determine the adsorption state of the adsorbent.
摘要:
A first exhaust gas sensor 5 (air-fuel ratio sensor) and a second exhaust gas sensor 6 (O2 sensor) are disposed respectively upstream and downstream of a catalytic converter. An exhaust system E which ranges from the exhaust gas sensor 5 to the exhaust gas sensor 6 and includes the catalytic converter 3 is regarded as an object exhaust system E, and a behavior of the object exhaust system E is modeled. When an internal combustion engine 1 is in operation, parameters to be set of the model of the object exhaust system E are sequentially identified based on the data of outputs of the exhaust gas sensors 5, 6. A deteriorated state of the catalytic converter 3 is determined based on the data of the identified values. Concurrent with the determination of the deteriorated state, a target air-fuel ratio for the internal combustion engine 1 is sequentially determined in order to converge the output of the exhaust gas sensor 5 to a given target value, and the air-fuel ratio of the internal combustion engine 1 is controlled to converge the output (the detected value of the air-fuel ratio) of the first exhaust gas sensor 5 to the target air-fuel ratio, for thereby allowing the catalytic converter 3 to achieve an optimum purifying capability. In this manner, the deteriorated state of the catalytic converter 3 can be determined in various operation states of the internal combustion engine 1 while keeping the purifying capability of the catalytic converter 3.
摘要:
A control system for an internal combustion engine having an exhaust system, an intake system, and an exhaust gas recirculation mechanism for recirculating exhaust gases from the exhaust system to the intake system is disclosed. The exhaust system is provided with an adsorbent for adsorbing hydrocarbon. When the adsorbent has adsorbed the hydrocarbon and the engine is operating in an idling condition, an intake air amount of the engine is increased and an ignition timing of said engine is retarded, and at the same time, the exhaust gas recirculation is performed to recirculate the hydrocarbon desorbed from the adsorbent to the intake system.
摘要:
A control system for controlling an internal combustion engine which discharge exhaust gases through an emission purifier includes a controller which increases the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling after the internal combustion engine has started to operate, to a level which is greater by a predetermined increase than the quantity of intake air drawn into the internal combustion engine while the internal combustion engine is idling normally. The controller also generates a command value for ignition timing of the internal combustion engine according to a feedback control process to converge the rotational speed of the internal combustion engine toward a predetermined target rotational speed, and controlling the ignition timing of the internal combustion engine based on the generated command value thereby to retard the ignition timing. The controller establishes the target rotational speed by changing the target rotational speed from a preset rotational speed toward a predetermined idling speed after the rotational speed of the internal combustion engine has reached the preset rotational speed which is higher than the idling speed after the quantity of intake air drawn into the internal combustion engine has started being increased.