Online Monitoring ICE Powers Based on the Crankshaft Angular Vibration

Abstract

A new method of online monitoring ICE powers based on the crankshaft angular vibration is proposed. It has deduced that when each cylinder works uniformly at a certain rotating speed, and the vth order angular vibration mode of crankshaft nears plane vibration mode such as “quasi-rigid body model” or “quasi-trapeziform model”, so a cubic polynomial can represent the relationship between the vth order angular vibration displacement amplitude of the crankshaft reference point and the engine powers, thereby the angular vibration of reference point could be used to online monitor engine powers. Through the simulation and experimental researches on a 6240 and a 4100 diesel engine, it shows that the engine powers fitted with the angular vibration displacement amplitudes of reference point are close to the measured or theoretical powers comparatively, and the maximum errors is only 2.95%, which verifies the feasibility and practicability of the method consequently.