Total process of fault diagnosis for wind turbine gearbox,from the perspective of combination with feature extraction and machine learning:A review

With the increasing of the installed capacity of wind power,the condition monitoring and maintains technique is becoming more important.Wind Turbines(WT)gearbox is one of the key wind power components as it plays the role of power transmission and speed regulation.Towards this,a number of scholars have pay attention to the fault diagnosis of WT gearbox.The efficiency of Machine Learning(ML)algorithms is highly correlated with signal type,data quality,and extracted features employed.The implementation of ML techniques has proven to be advantageous in simplifying the comprehension prerequisites for fault diagnosis technology concerning fault mechanisms.More and more current studies predominantly concentrate on the utilization and fine-tuning of ML algorithms,while providing limited insights into the features of the acquired data.Therefore,it is necessary to review the research in recent years from the perspective of the combination of feature extraction and ML algorithms,and provide a detailed direction for future WT gearbox fault diagnosis technology research.In this paper,data processing algorithms and typical fault diagnosis methods based on ML methods for WT gearbox are reviewed.For the using of ML method in WT gearbox fault diagnosis,the data prepared for training is very important.The paper firstly reviewed the data analysing method which will support the ML method.The data analysing methods include data acquisition,data preprocessing and feature extraction method.Feature extraction plays a pivotal role in the realm of gearbox fault diagnosis,as it serves as the essence of effective detection.This review will primarily focus on exploring methods that enable the utilization of efficient features in combination with ML techniques to achieve accurate gearbox fault diagnosis.Then typical ML method for WT gearbox fault diagnosis are carefully reviewed.Moreover,some prospects for future research directions are discussed in the end.

Cross-level steam load smoothing and optimization in industrial parks using data-driven approaches

This study focuses on the integrated energy production system in industrial parks, addressing the problem of stable load dispatch of equipment under demand fluctuations. A cross-level method for steam load smoothing and optimization is proposed, aiming to achieve stable production and optimal economic performance through three levels of integration: load forecasting, load dispatch, and load regulation. Unlike traditional methods that directly use load forecasting values, heat network elasticity is presented as a buffer between demand and supply. Constraints for minimal changes in equipment load and operational parameters are established for smooth regulation. Industrial cases demonstrate that the load forecasting model has mean absolute percentage errors of 2.44% and 1.68% for medium-pressure and low-pressure steam, respectively, meeting accuracy requirements. The modified supply-side load smoothness is effectively improved by considering heat network elasticity. The method increases boiler efficiency by 1.92%, reducing average coal consumption by 0.92 t/h. Compared to manual operation, the proposed model leads to an average increase of 5.69 MW in power generation and an average reduction of 10.81% in coal-to-electricity ratio. This study verifies the importance of smooth integration across different levels and analyzes the effective response of the proposed method to the uncertainty in load forecasting. The method demonstrates the enormous potential of data-driven methods in achieving safe, economical, and sustainable production in industrial parks.

Fault diagnosis for gearboxes based on Fourier decomposition method and resonance demodulation

Condition monitoring and fault diagnosis of gearboxes play an important role in the maintenance of mechanical systems.The vibration signal of gearboxes is characterized by complex spectral structure and strong time variability,which brings challenges to fault feature extraction.To address this issue,a new demodulation technique,based on the Fourier decomposition method and resonance demodulation,is proposed to extract fault-related information.First,the Fourier decomposition method decomposes the vibration signal into Fourier intrinsic band functions(FIBFs)adaptively in the frequency domain.Then,the original signal is segmented into short-time vectors to construct double-row matrices and the maximum singular value ratio method is employed to estimate the resonance frequency.Then,the resonance frequency is used as a criterion to guide the selection of the most relevant FIBF for demodulation analysis.Finally,for the optimal FIBF,envelope demodulation is conducted to identify the fault characteristic frequency.The main contributions are that the proposed method describes how to obtain the resonance frequency effectively and how to select the optimal FIBF after decomposition in order to extract the fault characteristic frequency.Both numerical and experimental studies are conducted to investigate the performance of the proposed method.It is demonstrated that the proposed method can effectively demodulate the fault information from the original signal.