Abstract: A method to control the combustion of an internal combustion engine, which comprises determining a combustion model, which provides a spark advance depending on an objective value of the rate of water to be injected, on the rotation speed, on the intake efficiency and on an open-loop contribution of a combustion index; calculating a first closed-loop contribution of the spark advance depending on the combustion index; calculating a second closed-loop contribution of the spark advance depending on a quantity indicating the knocking energy; and calculating the objective value of the spark advance angle to be operated through the sum of the spark advance value provided by the combustion model and of the first closed-loop contribution or, alternatively, of the second closed-loop contribution.

Abstract: A method to control the combustion of an internal combustion engine, which comprises determining a combustion model, which provides a spark advance depending on an objective value of the rate of water to be injected, on the rotation speed, on the intake efficiency and on an open-loop contribution of a combustion index; calculating a first closed-loop contribution of the spark advance depending on the combustion index; calculating a second closed-loop contribution of the spark advance depending on a quantity indicating the knocking energy; and calculating the objective value of the spark advance angle to be operated through the sum of the spark advance value provided by the combustion model and of the first closed-loop contribution or, alternatively, of the second closed-loop contribution.

Abstract: A method recognizes at least one feature of fuel in an internal-combustion engine (1). The method comprises steps of: detecting, by at least one sensor, intensity (S) of vibrations generated by the internal-combustion engine (1) within a measurement-time window; determining a value of at least one synthetic index (I) by processing the intensity (S) of the vibrations generated by the internal-combustion engine (1) within the measurement-time window; comparing a synthetic index (I) with at least one predetermined comparison quantity (TH); and recognizing the feature of the fuel as a function of the comparison between the synthetic index (I) and comparison quantity (TH).

Abstract: A method of controlling an internal combustion engine having at least one cylinder defining a variable-volume combustion chamber; and a rotating crankshaft powered by a piston sliding inside the cylinder; the control method including the steps of: determining a recording window expressed in engine angle degrees and having a start engine angle and a stop engine angle; acquiring and memorizing the intensity of sound pressure waves, generated by the internal combustion engine as a function of an engine angle, by means of at least one sound pressure sensor and within the recording window; and estimating the value of at least one operating parameter of a part of the internal combustion engine by analysing the intensity of the sound pressure waves in the recording window.

Abstract: A method recognizes at least one feature of fuel in an internal-combustion engine (1). The method comprises steps of: detecting, by at least one sensor, intensity (S) of vibrations generated by the internal-combustion engine (1) within a measurement-time window; determining a value of at least one synthetic index (I) by processing the intensity (S) of the vibrations generated by the internal-combustion engine (1) within the measurement-time window; comparing a synthetic index (I) with at least one predetermined comparison quantity (TH); and recognizing the feature of the fuel as a function of the comparison between the synthetic index (I) and comparison quantity (TH).

Abstract: A method of controlling the spark lead of an internal combustion engine having at least one cylinder fitted with a spark plug; the method including the steps of: determining a standard spark lead value; determining an engine knock index in the cylinder; calculating a correction factor as a function of the engine knock index; determining a modified spark lead value by applying the correction factor to the standard spark lead value; and controlling the spark plug using the modified spark lead value. The correction factor is calculated by statistically analyzing a number of engine knock indexes to calculate a cumulative distribution; comparing the cumulative distribution with at least one target value; and modifying the current correction factor value as a function of the comparison between the cumulative distribution and the target value.

Abstract: A method of controlling an internal combustion engine having at least one cylinder defining a variable-volume combustion chamber; and a rotating crankshaft powered by a piston sliding inside the cylinder; the control method including the steps of: determining a recording window expressed in engine angle degrees and having a start engine angle and a stop engine angle; acquiring and memorizing the intensity of sound pressure waves, generated by the internal combustion engine as a function of an engine angle, by means of at least one sound pressure sensor and within the recording window; and estimating the value of at least one operating parameter of a part of the internal combustion engine by analysing the intensity of the sound pressure waves in the recording window.

Abstract: A method of controlling the spark lead of an internal combustion engine having at least one cylinder fitted with a spark plug; the method including the steps of: determining a standard spark lead value; determining an engine knock index in the cylinder; calculating a correction factor as a function of the engine knock index; determining a modified spark lead value by applying the correction factor to the standard spark lead value; and controlling the spark plug using the modified spark lead value. The correction factor is calculated by statistically analyzing a number of engine knock indexes to calculate a cumulative distribution; comparing the cumulative distribution with at least one target value; and modifying the current correction factor value as a function of the comparison between the cumulative distribution and the target value.