Method and a relative device for diagnosing misfire or partial combustion conditions in an internal combustion engine
AssigneeSTMicroelectronics S.r.l.
InventorsFerdinando Taglialatela-Scafati, Nicola Cesario, Giovanni Di Lorenzo
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Abstract
A method of diagnosing misfire or partial combustion conditions in an internal combustion engine without using a phonic wheel discriminates the combustion conditions with soft-computing techniques directly exploiting a combustion pressure signal generated by a common pressure sensor installed in the cylinder. There exists an exploitably close correlation between the instantaneous values of the internal cylinder pressure and the occurrence of misfire or partial combustion conditions, and thus the cylinder pressure signal may be reliably used for diagnosing misfires or partial combustions in functioning conditions of the engine.
Claims14
A method of diagnosing misfire or partial combustion conditions in an internal combustion engine, the method comprising:
- sensing pressure in a combustion chamber of at least one cylinder of the engine, and generating at least one pressure signal based on the sensed pressure;
- extracting at least one operation parameter from the at least one generated pressure signal;
- and
- producing at least one signal representative of a misfire condition or of a partial combustion condition based on a value of the at least one extracted operation parameter, with the extracted operation parameter corresponding to an instantaneous value of a pressure ratio p(θ)/p(−θ), where P is the pressure in the combustion chamber of the at least one cylinder and θ is an angular position of the engine from Top Dead Center, for pre-established angular positions.
A device for diagnosing misfire or partial combustion conditions in an internal combustion engine, the device comprising:
- a pressure sensor for sensing pressure in a combustion chamber of at least one cylinder of the engine, and generating at least one pressure signal based on the sensed pressure;
- and
- an off-line machine configured to perform the following.
- receiving as input the at least one generated pressure signal,
- extracting at least one operation parameter from the at least one generated pressure signal, and
- producing at least one signal representative of a misfire condition or of a partial combustion condition based on a value of the at least one extracted operation parameter, with the extracted operation parameter corresponding to an instantaneous value of a pressure ratio P(θ)/P(−θ), where P is the pressure in the combustion chamber of the at least one cylinder, and θ is an angular position of the engine from Top Dead Center, for pre-established angular positions.
A method of diagnosing an internal combustion engine comprising:
- sensing pressure in at least one cylinder of the engine, and generating:
- at least one pressure signal based on the sensed pressure;
- extracting at least one operation parameter from the at least one generated pressure signal;
- and
- producing at least one signal representative of an engine condition based on a value of the at least one extracted operation parameter, with the extracted operation parameter corresponding to a pressure ratio P(θ)/P(−θ), where P is the pressure in the at least one cylinder and θ is an angular position of the engine with respect to a reference, for pre-established angular positions.
A device for diagnosing an internal combustion engine comprising;
- a pressure sensor for sensing pressure in a combustion chamber of at least one cylinder of the engine, and generating at least one pressure signal based on the sensed pressure;
- and
- an off-line machine configured to perform the following
- receiving as input the at least one generated pressure signal,
- extracting at least one operation parameter from the at least one generated pressure signal, and
- producing at least one signal representative of an engine condition based on a value of the at least one extracted operation parameter, with the extracted operation parameter corresponding to an instantaneous value of a pressure ratio P(θ)/P(−θ),
- where P is the pressure in the combustion chamber of the at least one cylinder, and θ is an angular position of the engine with respect to a reference;
- for pre-established angular positions.
Dependencies are inferred from the claim text.