Abstract:
An acceleration based misfire detection system with improved signal fidelity comprises a measurement device (421, 423, 425, 427) for determining an operating condition of the powertrain (401). The operating condition can include engine speed, engine load, as well as other conditions. A misfire detector (417) provides a misfire indication (419) dependent on an improved fidelity acceleration signal (415). The improved fidelity acceleration signal (415) is provided by either a median filter (413) operating on an acceleration signal (411) where the median filter's rank is programmable dependent on the determined operating condition of the powertrain, a highpass filter operating on an acceleration signal (411) where the highpass filter's order is programmable dependent on the determined operating condition of the powertrain, or from an acceleration determination device (409) acting on velocity information provided by a lowpass filter (407) operating on a velocity signal (406) where the lowpass filter's order is programmable dependent on the determined operating condition of the powertrain, or a combination of the above.
Abstract:
A misfire detection method and apparatus includes measurement of combustion induced torque in an internal combustion engine and provision of time-ordered first, second, and third acceleration data samples dependent on torque. A misfire is indicated (513) when a magnitude of the second acceleration data sample has a magnitude less than a misfire threshold (517), and less than a magnitude of both the first and third acceleration data samples (511).
Abstract:
A misfire detection method and apparatus includes measurement of combustion induced torque in an internal combustion engine and provision of time-ordered first, second, and third acceleration data samples dependent on torque. A misfire is indicated (513) when a magnitude of the second acceleration data sample has a magnitude less than a misfire threshold (517), and less than a magnitude of both the first and third acceleration data samples (511).
Abstract:
A misfire detection method and apparatus includes measurement of combustion induced torque in an internal combustion engine and provision of time-ordered first, second, and third acceleration data samples dependent on torque. A misfire is indicated (513) when a magnitude of the second acceleration data sample has a magnitude less than a misfire threshold (517), and less than a magnitude of both the first and third acceleration data samples (511).
Abstract:
A method and apparatus for adaptive profile correction for rotating position encoders in reciprocating engines measures a raw engine speed derived from a rotating position encoder (107) driven by a reciprocating engine. A first corrected engine speed (1103) is provided dependent on the raw engine speed and a predetermined first encoder profile while the engine is operating bounded within a first speed range (905), and a second corrected engine speed (1103) is provided dependent on the raw engine speed and a predetermined second encoder profile while the engine is operating bounded within a second speed range (903). A microcontroller (1205) derives a processed acceleration signal (1207) dependent on the measured engine speed and provides it to an external acceleration based misfire detection system (1201) which provides a misfire indication (1203) back to the microcontroller (1205) if a combustion misfire behaviour is detected in the processed acceleration signal (1207).
Abstract:
An acceleration based misfire detection system with improved signal fidelity comprises a measurement device (421, 423, 425, 427) for determining an operating condition of the powertrain (401). The operating condition can include engine speed, engine load, as well as other conditions. A misfire detector (417) provides a misfire indication (419) dependent on an improved fidelity acceleration signal (415). The improved fidelity acceleration signal (415) is provided by either a median filter (413) operating on an acceleration signal (411) where the median filter's rank is programmable dependent on the determined operating condition of the powertrain, a highpass filter operating on an acceleration signal (411) where the highpass filter's order is programmable dependent on the determined operating condition of the powertrain, or from an acceleration determination device (409) acting on velocity information provided by a lowpass filter (407) operating on a velocity signal (406) where the lowpass filter's order is programmable dependent on the determined operating condition of the powertrain, or a combination of the above.
Abstract:
A method and apparatus for adaptive profile correction for rotating position encoders in reciprocating engines measures a raw engine speed derived from a rotating position encoder (107) driven by a reciprocating engine. A first corrected engine speed (1103) is provided dependent on the raw engine speed and a predetermined first encoder profile while the engine is operating bounded within a first speed range (905), and a second corrected engine speed (1103) is provided dependent on the raw engine speed and a predetermined second encoder profile while the engine is operating bounded within a second speed range (903). A microcontroller (1205) derives a processed acceleration signal (1207) dependent on the measured engine speed and provides it to an external acceleration based misfire detection system (1201) which provides a misfire indication (1203) back to the microcontroller (1205) if a combustion misfire behaviour is detected in the processed acceleration signal (1207).
Abstract:
An acceleration based misfire detection system with improved signal fidelity comprises a measurement device (421, 423, 425, 427) for determining an operating condition of the powertrain (401). The operating condition can include engine speed, engine load, as well as other conditions. A misfire detector (417) provides a misfire indication (419) dependent on an improved fidelity acceleration signal (415). The improved fidelity acceleration signal (415) is provided by either a median filter (413) operating on an acceleration signal (411) where the median filter's rank is programmable dependent on the determined operating condition of the powertrain, a highpass filter operating on an acceleration signal (411) where the highpass filter's order is programmable dependent on the determined operating condition of the powertrain, or from an acceleration determination device (409) acting on velocity information provided by a lowpass filter (407) operating on a velocity signal (406) where the lowpass filter's order is programmable dependent on the determined operating condition of the powertrain, or a combination of the above.