Estimation of the engine revolution for statistical analysis of R.M.S value by using Prony method to detect misfiring cylinder of the diesel engine

Mechanical problems with large-scale mining machinery can cause serious losses in operational efficiency and profits. A diesel engine with a misfiring cylinder is likely to break down in a short period of time when the engine is used without maintenance. The authors have developed a new system to detect whether an engine is misfiring and, if so, which cylinder is misfiring. This system is able to manage the engine from a remote location. In this study, a minimum number of sensors are applied on two cylinders of the engine in order to detect misfiring cylinder. The measured waveform was analyzed by the statistical analysis of R.M.S value. Dividing up combustion time of each cylinder is the first step for statistical analysis of R.M.S value. In case of idling state of the engine, it is easy to divide up combustion time. But, it is necessary to find engine revolutions under the state of rotational fluctuation of the engine. The period of combustion time vary every hour under the state of rotational fluctuation. Therefore, engine revolutions were computed by using Prony method. The period of combustion time was divided, and R.M.S value was calculated