Performance Assessment of APU Based on Degradation Enhancement With On-Wing Sensing Data

The aircraft auxiliary power unit (APU) is a small turbine engine that provides power and air sources for the aircraft. Its main role is to help start the main engine and provide electric power to the aircraft. The accurate performance assessment (PA) of on-wing APUs can help improve the safety of APUs while reducing unnecessary maintenance costs for airlines. Due to the hostile operating environment and working conditions, the performance parameters are affected greatly. It is difficult to conduct the PA for on-wing APU. In this article, a multiparameter PA approach based on degradation feature enhancement is proposed to fulfill the PA of on-wing APU. First, an adaptive feature extraction variational mode decomposition is proposed to extract the degradation features from the on-wing sensing data and obtain a feature set of the monitored parameters. Then, the extracted degradation features are fused through a long short-term memory (LSTM) network for achieving PA. To evaluate the effectiveness of the proposed method, experiments are conducted based on real on-wing sensing data from airlines. The PA results show that the proposed approach can obtain better PA results.