METHOD OF DETERMINING TECHNICAL STATE OF INTERNAL COMBUSTION ENGINES AND EXPERT SYSTEM FOR REALISING SAID METHOD Russian patent published in 2011 - IPC G01M15/04 

FIELD: physics.

SUBSTANCE: invention relates to determination of the technical state by measuring parameters which reflect pressure in reciprocating internal combustion engine cylinders in operating conditions. The method of determining the technical condition of an internal combustion engine involves measuring and averaging in functions of the crankshaft rotation angle, as well as time, instantaneous values of the investigated parameters, determining characteristics of the measured parameters, analysing and comparing with reference values, determining the presence and degree of faults and classifying the technical state of the internal combustion engine. Instantaneous values are measured after a cycle or power stroke or after specific parts of the cycle of the internal combustion engine. Specific parts can be parts of zones for relaying pistons or zones outside said parts. Measuring is carried out in stationary mode with maximum load at given rotation frequency or in acceleration mode without loading or on a regulatory area with speed characteristic. The measured parameters are: torque, angular speed and acceleration of the crankshaft or turbocompressor rotor, or displacement of the fuel pump rod or pressure in pipes to injection nozzles as well as other parameters which reflect cyclic fuel injection. Characteristics of the measured parameters are: gradient, rate of change, gradient overshooting, rate of change in form of pulses or differential probability distribution laws of the obtained processes and overshooting of these laws in form of pulses or variance and mean-square deviation of the obtained processes, or two-dimensional differential probability distribution laws of the obtained processes. Standard parameters are pre-measured parameters as well as relationships obtained before hand of parameters of the measured quantities associated with pressure in cylinders of a properly functioning internal combustion engine. The expert system for determining the technical state of an internal combustion engine is designed to realise the described method.

EFFECT: simplification, low labour input and high accuracy of determining the technical state of an internal combustion engine.

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