Abstract:
A method for controlling fuel injection in a multifuel internal-combustion engine (1); the control method envisages the steps of: receiving a request for fuel switching at a first instant (T 0 ); waiting, starting from the first instant (T 0 ), for a first time interval (A) during which fuel switching has never been performed; carrying out, starting from a second instant (T 1 ) and for a second time interval (B), fuel switching only if a cut-off phase or else an idling phase occurs; carrying out, starting from a third instant (T 2 ) and for a third time interval (C), fuel switching only if a cut-off phase, an idling phase, or else a stabilized-r.p.m. phase occurs; and carrying out, starting from a fourth instant (T 3 ) fuel switching in any condition.
Abstract:
A method for controlling fuel injection in a multifuel internal-combustion engine (1) that can inject alternatively a liquid fuel and a gaseous fuel; the control method envisages the steps of: injecting the gaseous fuel by means of at least one corresponding injector (15); cyclically measuring the pressure (P rail ) of the gaseous fuel within the common channel (22); determining at least one upper-limit threshold (P rail-min ; P rail-max ) for the pressure (P rail ) of the gaseous fuel within the common channel (22); comparing the pressure (P rail ) of the gaseous fuel within the common channel (22) with the upper-limit threshold (P rail-min ; P rail-max ); and carrying out an automatic fuel switch from the gaseous fuel to the liquid fuel when the pressure (P rail ) of the gaseous fuel within the common channel (22) exceeds the upper-limit threshold (P rail-min ; Prail-max).
Abstract:
An electronic concentration control system in which a first exhaust gas composition sensor (16) located in an exhaust pipe (9) downstream from a catalytic converter (11) is connected to an input to a P.I. circuit (28) which generates a control output signal (K02) comprising a succession of opposing triangular ramps. The system includes a second exhaust gas composition sensor (14) located in the exhaust pipe (9) upstream from the catalytic converter (11) generating a signal which is fed to a proportional integral circuit (30) whose integrating and multiplying coefficients (Ki,Kp) are altered on the basis of the control signal (K02). The system further comprises a diagnostic circuit (50) for detecting malfunction function of the second exhaust gas composition sensor (14).
Abstract:
An electronic concentration control system in which a first exhaust gas composition sensor (16) located in an exhaust pipe (9) downstream from a catalytic converter (11) is connected to an input to a P.I. circuit (28) which generates a control output signal (K02) comprising a succession of opposing triangular ramps. The system includes a second exhaust gas composition sensor (14) located in the exhaust pipe (9) upstream from the catalytic converter (11) generating a signal which is fed to a proportional integral circuit (30) whose integrating and multiplying coefficients (Ki,Kp) are altered on the basis of the control signal (K02). The system includes a diagnostic circuit (50) which checks the efficiency of the first and second sensors (16, 14).
Abstract:
An electronic concentration control system in which a first exhaust gas composition sensor (16) located in an exhaust pipe (9) downstream from a catalytic converter (11) is connected to an input to a P.I. circuit (28) which generates a control output signal (K02) comprising a succession of opposing triangular ramps. The system includes a second exhaust gas composition sensor (14) located in the exhaust pipe (9) upstream from the catalytic converter (11) generating a signal which is fed to a proportional integral circuit (30) whose integrating and multiplying coefficients (Ki,Kp) are altered on the basis of the control signal (K02).
Abstract:
An electronic concentration control system in which a first exhaust gas composition sensor (16) located in an exhaust pipe (9) downstream from a catalytic converter (11) is connected to an input to a P.I. circuit (28) which generates a control output signal (K02) comprising a succession of opposing triangular ramps. The system includes a second exhaust gas composition sensor (14) located in the exhaust pipe (9) upstream from the catalytic converter (11) generating a signal which is fed to a proportional integral circuit (30) whose integrating and multiplying coefficients (Ki,Kp) are altered on the basis of the control signal (K02).