Abstract: A power supply control system includes a power generator, a power supply configured to be charged with power supplied by the power generator, an electrical load configured to operate according to the power supplied by the power generator, and a control unit configured to charge the power supply until a predetermined period elapses after switching from an operation state in which the electrical load is operated to a non-operation state when the power generator generates the power.

Abstract: A power supply control system includes a power generator, a power supply configured to be charged with power supplied by the power generator, an electrical load configured to operate according to the power supplied by the power generator, and a control unit configured to charge the power supply until a predetermined period elapses after switching from an operation state in which the electrical load is operated to a non-operation state when the power generator generates the power.

Abstract: An exhaust emission control system for an internal combustion engine is disclosed. The system includes a NOx removing device provided in an exhaust system of the engine for removing NOx contained in exhaust gases, and an oxygen concentration sensor provided in the exhaust system. The air-fuel ratio of the air-fuel mixture to be supplied to the engine is changed from a value which is leaner than the stoichiometric ratio to a value which is richer than the stoichiometric ratio. It is determined whether or not a sulfur oxide concentration in the exhaust gases is high according to a transient characteristic of an oxygen concentration detected by the oxygen concentration sensor after the air-fuel ratio is changed.

Abstract: An exhaust emission control system for an internal combustion engine is disclosed. The system includes a NOx removing device provided in an exhaust system of the engine for removing NOx contained in exhaust gases, and an oxygen concentration sensor provided in the exhaust system. The air-fuel ratio of the air-fuel mixture to be supplied to the engine is changed from a value which is leaner than the stoichiometric ratio to a value which is richer than the stoichiometric ratio. It is determined whether or not a sulfur oxide concentration in the exhaust gases is high according to a transient characteristic of an oxygen concentration detected by the oxygen concentration sensor after the air-fuel ratio is changed.

Abstract: In a valve timing control apparatus for an internal combustion engine using an oil pressure control, a feedback correction amount is calculated so as to have a linear term proportional to a deviation between a target value and an actual value of the valve timing control apparatus, and a non-linear term using a switching function by a sliding mode control. Further, a dither control is added to the feedback correction amount and a learning is performed for a basic control amount and a control gain. Therefore, a control can be executed with high robust, high accuracy and quick response.

Abstract: A valve timing control apparatus in an internal combustion engine is feedback controlled by a sliding mode control and an abnormality of the sliding mode control is diagnosed. During a slight abnormality other than a crucial abnormality which makes the feedback control impossible, the system is feedback controlled to converge to a target value using only a non-linear term calculated by the sliding mode control.

Abstract: In electronically controlling the opening of a throttle valve mounted in an intake system of an engine, the opening is controlled through a sliding mode control, based on a control amount including a control amount portion proportional to the switching function and a control amount portion corresponding to a nonlinear spring torque of a return spring urging said throttle valve in a direction to reduce the throttle valve opening. According to this constitution, the response characteristic of the control unit is maintained while restraining overshoot, enabling the opening to converge to the target opening promptly while sliding along a switching plane. Further, since said control amount includes the control amount portion corresponding to the nonlinear spring torque of the return spring, uncertainty element is reduced, to thereby perform a high response control.

Abstract: Duplex fail-safe systems are equipped for outputting fail-safe control signals when a failure is determined by a read/write diagnosis of a RAM, and the logic for the logic operation performed by one of said systems is set to be reverse to the logic for the logic operation performed by the other system.

Abstract: A valve timing control apparatus in an internal combustion engine is feedback controlled by a sliding mode control and an abnormality of the sliding mode control is diagnosed. During a slight abnormality other than a crucial abnormality which makes the feedback control impossible, the system is feedback controlled to converge to a target value using only a non-linear term calculated by the sliding mode control.