In-cylinder combustion detection based on logarithmic instantaneous angular successive speed ratio

Abstract

Performance of an internal combustion (IC) engine directly depends on quality of combustion. A direct way to detect the combustion is mainly done by measuring in-cylinder pressure by a pressure measuring sensor. However, sensor's cost is very high and its installation on the cylinder head is a tricky assignment. Therefore, in this paper, IAS signal measured from the output shaft, has been used to detect the combustion inside the engine cylinder. The advantage of IAS signal is that it is less noisy compared to other engine responses like vibration signal, acoustic signal etc. In IC engine, the speed fluctuation during power stroke is higher as compared to suction, compression and exhaust. Based on this idea, IAS signal based algorithm has been developed to detect combustion in a single cylinder four stroke spark ignition engine.