Aircraft Engine On-Line Diagnostics Through Dual-Channel Sensor Measurements: Development of a Baseline System

Abstract

In this paper, a baseline system which utilizes dual-channel sensor measurements for aircraft engine on-line diagnostics is developed. This system is composed of a linear on-board engine model (LOBEM) and fault detection and isolation (FDI) logic. The LOBEM provides the analytical third channel against which the dual-channel measurements are compared. When the discrepancy among the triplex channels exceeds a tolerance level, the FDI logic determines the cause of the discrepancy. Through this approach, the baseline system achieves the following objectives: 1) anomaly detection, 2) component fault detection, and 3) sensor fault detection and isolation. The performance of the baseline system is evaluated in a simulation environment using faults in sensors and components.

Aircraft Engine On-Line Diagnostics Through Dual-Channel Sensor Measurements: Development of an Enhanced System

“…Up to this point, the signals generated from the triplex channels are computed in the same way as those used in the baseline system [5]. In conjunction with these signals, the enhanced system utilizes the following residuals generated by the HKF: The residual in Eq.…”

“…[5] is composed of a linear on-board engine model (LOBEM) and fault detection and isolation (FDI) logic as shown in Fig. 1.…”

“…As discussed in Ref. [5], in order to update the LOBEM to a new health baseline, the piecewise linear models must be re-generated at the new health condition. Such complexity can raise a number of practical issues in utilizing the LOBEM.…”

“…[5], the CFS is computed specifically for the purpose of component fault detection. The scalars α and β in Eq.…”

“…In Ref. [5], a linear on-board engine model (LOBEM), which is composed of piecewise linear models generated at multiple operating conditions over the flight envelope, was utilized for the development of a baseline system for aircraft engine on-line diagnostics. This baseline system established the level of diagnostic performance which is potentially achievable in the field.…”