Honda Motor Co., Ltd.

Mitsunobu Saito

Yuji Yasui

Hiroshi Tagami

Kosuke Higashitani

Masahiro Sato

Akiyuki Yonekawa

Tadaharu Shoji

A control system for an internal combustion engine, which is capable of enhancing the accuracy of fuel control and ignition timing control even when there is a possibility that the reliability of a calculated intake air amount lowers, and enables reduction of manufacturing costs. An ECU of the control system calculates a first estimated intake air amount according to a valve lift, a cam phase, and a compression ratio, calculates a second estimated intake air amount according to the flow rate of air detected by an air flow sensor. The ECU determines a fuel injection amount according to the first estimated intake air amount when an estimated flow rate Gin_vt calculated based on an engine speed, the valve lift, the cam phase, and the compression ratio is within the range of Gin_vt&#x2266;Gin, and according to the second estimated intake air amount when GinGin_vt.

Control system for internal combustion engine

A control system which is capable of compensating for and suppressing the influence of a periodic disturbance on a controlled object more quickly, even when the controlled object is subjected to the periodic disturbance the amplitude of which periodically changes, thereby enhancing the stability and the accuracy of control. The control system includes an ECU. The ECU calculates disturbance compensation values for compensating for a periodic disturbance by searching maps and tables, in timing of generation of each pulse of a CRK signal. The ECU calculates control inputs at a predetermined control period, with predetermined control algorithms, according to the disturbance compensation values read in at the control period, respectively.

Control system

A control system for an internal combustion engine, which is capable of enhancing the accuracy of fuel control and ignition timing control even when there is a possibility that the reliability of a calculated intake air amount lowers, and enables reduction of manufacturing costs. An ECU of the control system calculates a first estimated intake air amount according to a valve lift, a cam phase, and a compression ratio, calculates a second estimated intake air amount according to the flow rate of air detected by an air flow sensor. The ECU determines a fuel injection amount according to the first estimated intake air amount when an estimated flow rate Gin_vt calculated based on an engine speed, the valve lift, the cam phase, and the compression ratio is within the range of Gin_vt&#x2266;Gin, and according to the second estimated intake air amount when Gin&#x2266;Gin_vt.

A control system for an internal combustion engine, which is capable of properly performing air-fuel ratio control and ignition timing control according to an actual amount of intake air, even when reliability of the results of detection of the operating condition of a variable intake mechanism is low. The control system for controlling air-fuel ratio and ignition timing includes an ECU. The ECU calculates a target air-fuel ratio, calculates an air-fuel ratio correction coefficient, calculates a statistically processed value of an air-fuel ratio index value, calculates a corrected valve lift and a corrected cam phase, and determines a fuel injection amount according to the corrected valve lift, the corrected cam phase, and the air-fuel ratio correction coefficient.

A control system which is capable of enhancing both the stability and the accuracy of control when the output of a controlled object is feedback-controlled by a plurality of control inputs. An ECUof a control systemcontrols engine speed NE during idling by an ignition control input Usl_ig and an intake control input Usl_ar. The ECUcalculates a target engine speed NE_cmd according to an engine coolant temperature TW and the like (step), and determines the ignition control input Usl_ig and the intake control input Usl_ar with a plurality of predetermined target value filter-type two-degree-of-freedom sliding mode control algorithms [equations (1) to (12)] sharing one switching function &#x3c3;ne therebetween, such that the engine speed NE converges to the target engine speed NE_cmd (stepstoand).

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.

Growing community of inventors

Saitama-ken, Japan

Mitsunobu Saito