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Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Open Circuit Fault Diagnosis Strategy For Switch Of Three Level Inverter, Yanxia Shen, Beibei Miao
Open Circuit Fault Diagnosis Strategy For Switch Of Three Level Inverter, Yanxia Shen, Beibei Miao
Journal of System Simulation
Abstract: Fault diagnosis of switch is the premise of reliable operation of three-level-inverter under the fault of the switch. Taking simple open circuit fault of the diode neutral point clamped (NPC) three level inverter as an example, the open circuit fault diagnosis method based on the combination of online and offline diagnoses is proposed. The fault phase is detected by the mean value of the bridge arm phase voltages. In the time domain, the fault switch tube is diagnosed by the maximum and minimum values of the load phase voltages. In the frequency domain, the amplitude of the fault signal …
Current Sensor Fault Diagnosis For Induction Motor In Vector Control System, Sun Kai, Baina He, Sarah Odofin, Gu Yu
Current Sensor Fault Diagnosis For Induction Motor In Vector Control System, Sun Kai, Baina He, Sarah Odofin, Gu Yu
Journal of System Simulation
Abstract: A current sensor fault diagnosis method of induction motor in vector control system is proposed. A state-space form including sensor faults and environmental disturbances/noises of induction machine is described. An augmented observer is designed to simultaneously estimate system states, and current sensor faults. To attenuate the effects from the environmental disturbances/noises, a genetic algorithm is employed to design observer gain by minimizing the estimation error against environmental disturbances and noises. A simulation model based on Matlab and real-data of the induction motor collected by experiment is utilized to validate the proposed methods, which show the efficiency of the proposed …
Fault Co-Simulation Of Fuel Regulator In A Certain Type Of Turbofan Engine, Wei Xiang, Benwei Li, Xinyi Yang, Xingbo Wang
Fault Co-Simulation Of Fuel Regulator In A Certain Type Of Turbofan Engine, Wei Xiang, Benwei Li, Xinyi Yang, Xingbo Wang
Journal of System Simulation
Abstract: A co-simulation method for fuel regulator fault diagnosis in a certain type of turbofan engine is performed, which consists of AMEsim Model of main fuel control system and Simulink Model of aero-engine. The AMEsim Model of main fuel system and Simulink Model of aero-engine are built and their accuracy is validated by experiments and the engine’s operating data, respectively. The co-simulation model based on the main fuel control system and the aero-engine is proposed through the interface of AMEsim and Simulink software. The typical faults and obviation methods are simulated by the co-simulation model. The research shows that the …
Fault Diagnosis Of High Speed Train Bogie Based On Multi-Domain Fusion Cnn, Yunpu Wu, Weidong Jin, Yingkun Huang
Fault Diagnosis Of High Speed Train Bogie Based On Multi-Domain Fusion Cnn, Yunpu Wu, Weidong Jin, Yingkun Huang
Journal of System Simulation
Abstract: The performance degradation and failures of high-speed train bogie components directly threaten the operation security of train. A fault detection method based on multi-domain fusion convolutional neural network is proposed to address the high complexity, high coupling and strong nonlinearity of vibration signals. Noise injection for time domain signal is used to enhance noise robustness and generalization of the model. Signal time-frequency representation information is obtained through embedded time-frequency transformation layer. Adaptive weight-based fusion is implemented through intrinsic characteristics of the convolutional neural network to handle the multi-domain multi-channel information. The experimental results show that the proposed method improves …
Simulation Of Surge And Stall For Aero Engine Compressor Based On Entropy, Pi Jun, Yongchao Qiu, Zhiwei Hu, Wu Wei
Simulation Of Surge And Stall For Aero Engine Compressor Based On Entropy, Pi Jun, Yongchao Qiu, Zhiwei Hu, Wu Wei
Journal of System Simulation
Abstract: The mature model NASA Rotor37 is used to simulate the transition of the compressor’s operation from the steady state to the non-steady state of stall and surge using the simulation software CFX. The transition is analyzed and researched based on the theory of thermodynamics entropy and sample entropy to provide a basis for the fault diagnosis of stall and surge. The two thermodynamic entropy parameters of average specific entropy value and the isentropic efficiency are found by the analysis changing abnormally in the event of stall. The values of the sample entropy obtained by calculation using the static …
Health Warning And Fault Diagnosisof Pulverizing System Based On Syncretic Similarity, Songming Jiao
Health Warning And Fault Diagnosisof Pulverizing System Based On Syncretic Similarity, Songming Jiao
Journal of System Simulation
Abstract: It is an arduous task to know health statusof a pulverizing system in power plant by monitoring these parameters simultaneously and the fault diagnosing process is complicated.An approach based on syncretic similarity is presented which is suitable for industrial system’s health warning and fault diagnosis.The syncretic similarity couples anew type of weighted mahalanobis distance based on principal component analysiswith an improved weighted sine similarity. The approachhas self-learning ability.Central parameterswhich are used to compute similarity can be modified along with the operation process.Simulation resultsshow that the method is suitable for online application because of its high accuracy, fast …
Transformer Fault Diagnosis Based On Feature Extraction Of Relative Transformation Principal Component Analysis, Yongbo Tang, Yinguo Xiong
Transformer Fault Diagnosis Based On Feature Extraction Of Relative Transformation Principal Component Analysis, Yongbo Tang, Yinguo Xiong
Journal of System Simulation
Abstract: In order to handle the problem that the feature extraction of dissolved gas analysis (DGA) data by principal component analysis (PCA) is not distinct, a new transformer fault diagnosis method based on relative transformation (RT) PCA is proposed. The original data space is converted to the relative data space by relative transformation which makes the transformed data more distinguishable. PCA is employed to reduce the dimension of relative space to make the features more representative in the relative space. Diagnosis model based on least squares support vector machine (LSSVM) is set up according to the fault characteristic of transformer. …