Accelerated Life Testing and Remaining Useful Life Prediction Research of Gear Pumps
摘要
Gear pumps play an important role in ensuring the reliable operation of hydraulic systems and actuators. However, their degradation is affected by the coupling of mechanical wear and hydraulic performance deterioration. Remaining useful life prediction based on a single sensor signal may therefore lead to large errors. In addition, the high reliability requirement of gear pumps makes life-cycle degradation data difficult to obtain.
MethodsTo address these problems, a three-stress accelerated life test was designed for gear pumps to reduce the test time and obtain degradation data. Multidomain vibration features were extracted from the acquired signals in the time domain, frequency domain, and time-frequency domain. These features were then fused with volumetric efficiency data using kernel principal component analysis to construct degradation indicators. Finally, an Attention-Seq2Seq-BiGRU model was developed to capture long-term degradation information and predict the remaining useful life of gear pumps.
ResultsThe proposed method achieved accurate RUL prediction for gear pumps. The fused features based on vibration signals and volumetric efficiency data improved prediction stability. Compared with GRU, LSTM, BiGRU, and Seq2Seq-BiGRU models, the proposed Attention-Seq2Seq-BiGRU model showed the best prediction performance.
ConclusionsThe proposed framework effectively combines accelerated life testing, KPCA-based feature fusion, and Attention-Seq2Seq-BiGRU modeling. The results demonstrate that this method can improve the accuracy and stability of gear pump RUL prediction.