Diagnostic Methodology of the Low Displacement Diesel Engine Vibration Signal for Identification of Operating Conditions

摘要

The power developed by an engine is one of the main indications of its operating condition since it directly reflects changes in its performance and, therefore, the possibility of faults or anomalies. Usually, this parameter is measured directly by the use of dynamometers. However, in most real operating conditions, it is impractical or impossible to install this equipment. Additionally, diagnostic techniques generally require a level of intrusion that can cause engine damage. Therefore, in this study, a diagnostic methodology based on the indirect measurement of the engine output power is presented. The experimental procedure has been carried out in a single-cylinder diesel engine, which operates in four different operating conditions: 25%, 50%, 75%, and 100%. The methodology is based on the use of the engine vibration signal as a tool to identify different operating loads. By calculating the velocity of the vibration and the implementation of an algorithm based on the Inductive Monitoring System (IMS), it has been possible to relate the changes in the speed of vibration to the percentage of engine load. This methodology has showed an accuracy between a range of 84% and 94%, which demonstrates its reliability.