Once the pump fails, it may lead to shutdown or affect product quality. Zhu, “ Electrochemical coupled analysis of a micro piezo-driven focusing mechanism,” Micromachines 11(2), 216 (2020). Qian et al., “ Research on the control strategy of hydraulic shaking table based on the structural flexibility,” IEEE Access 7, 43063– 43075 (2019). Ji et al., “ Mechanism and propagation characteristics of rotating stall in a mixed-flow pump,” Renewable Energy 153, 74– 92 (2020). Known as the “heart” of the hydraulic system, it has been widely used in machinery equipment of the diverse fields, including industry and national defense. Hydraulic pump is the essential power source of the hydraulic transmission system.
![relative entropy relative entropy](https://image.slidesharecdn.com/relativeentropyandsquahedentanglement-130708021720-phpapp01/95/relative-entropy-andsquahedentanglement-16-1024.jpg)
The desired useful signals are also accurately reconstructed. It provides an effective solution for the reduction of the interference of useless signals, including the direct current component and noise. Through the validation of the numerical experiment and measured data, the results indicate that the method presents good ability in the useful component extraction for signals with multi-frequency vibration. The original signal can be automatically separated by FEMD, and the useful components of the signal can be obtained via the measurement of relative entropy. In this work, based on fast empirical mode decomposition (FEMD) and relative entropy, a novel method is proposed for extracting the effective components of the signal. It is also necessary to extract the effective components in condition monitoring of the hydraulic pump.
![relative entropy relative entropy](https://cdn.statically.io/img/miro.medium.com/max/1400/1*qo2h32s5zR3aLOyYYLFNuw.png)
It is of great significance to explore the monitoring of the health status of the hydraulic pump. As the core power source of the hydraulic transmission system, hydraulic pump has been widely used in various industrial machinery and national defense equipment.