- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Nonlinear Wave Dynamics of Unstable Atherosclerotic Plaque
摘要： Fault diagnosis of inductions motors has received much attention recently. Most of the works use data obtained either from the time domain or by applying advanced techniques in the frequency domain. Some researchers have employed a considerable effort in designing sophisticated algorithms to achieve the best performance of the diagnosis system. However, some contributions in the field have not taken advantage of the benefits that a good evaluation stage can bring to the developing of classifiers for fault diagnosis. In this paper, novel insights for the classifier evaluation are presented to promote better assessment practices in the field of electric machine diagnosis based on supervised classification. A case of study consisting of a motor with a broken rotor bar is described to analyze the performance of two classifiers by using scores focused on the fault detection. Also, different error estimation methods are considered to obtain unbiased predictive performances. Two statistical tests are also discussed to confirm the significance of the results under a single data set.
关键词： fault diagnosis,Broken rotor bar,electric machines,classification algorithm,condition monitoring,performance evaluation
更新于2025-09-19 17:13:59
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A High-Sensitivity Temperature Sensor Based on Glycerol-Filled Tellurite Microstructure Optical Fiber
摘要： This paper addresses the application of rotor speed signal for the detection and diagnosis of ball bearing faults in rotating electrical machines. Many existing techniques for bearing fault diagnosis (BFD) rely on vibration signals or current signals. However, vibration- or current-based BFD techniques suffer from various challenges that must be addressed. As an alternative, this paper takes the initial step of investigating the efficiency of rotor speed monitoring for BFD. The bearing failure modes are reviewed and their effects on the rotor speed signal are described. Based on this analysis, a novel BFD technique, the rotor speed-based BFD (RSB-BFD) method under variable speed and constant load conditions, is proposed to provide a benefit in terms of cost and simplicity. The proposed RSB-BFD method exploits the absolute value-based principal component analysis (PCA), which improves the performance of classical PCA by using the absolute value of weights and the sum square error. The performance and effectiveness of the RSB-BFD method is demonstrated using an experimental setup with a set of realistic bearing faults in the outer race, inner race, and balls.
关键词： principal component analysis (PCA),Bearing fault diagnosis (BFD),sum square error,variable speed,rotor speed
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Open-source integrated optical modelling with RayFlare
摘要： An output line-to-line voltage model-based fault diagnostic technique is presented in this paper. From the theoretical analysis of the output voltage under normal and faulty conditions, a preprocessing method is developed to extract fault features from diagnosis eigenvalue. A voltage envelope line is generated by the proposed voltage envelope function. By comparing the preprocessed diagnosis eigenvalue and the voltage envelope, single-switch open-circuit faults can be located precisely. Because the proposed method does not rely on the accurate amplitude of the output line-to-line voltage, the influence of the load changing is minimized and simple hardware is adopted, which has advantages of low cost, high reliability, and short diagnosis time. Moreover, as long as the inverter output voltages have the feature of periodic nonpositive and nonnegative, this method is valid no matter what control strategy is adopted by the inverter and no control signal is required for the diagnosis process. The prototype system is tested to validate the adaptability of the proposed method under different conditions, such as the diverse loads, various control strategies, and fault-occurrence time.
关键词： Fault diagnosis,fault location,open-circuit fault,inverters
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Highly Reliable Multi-Port Smart Inverter Modules for PV-Based Energy Systems
摘要： A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA in a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this paper we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.
关键词： radiation effects,fault diagnosis,field programmable gate arrays,Emulation
更新于2025-09-16 10:30:52
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[IEEE IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society - Lisbon, Portugal (2019.10.14-2019.10.17)] IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society - A Secondary Classification Fault Diagnosis Strategy Based on PCA-SVM for Cascaded Photovoltaic Grid-connected Inverter
摘要： The cascaded H-bridge multilevel inverter for grid-connected photovoltaic(PV) system has the advantages of high power quality and easy modularization, but as the levels of the inverter increase, the failure probability of the power switching devices will also increase. In the open-circuit faults of the power switching devices, there are two groups of similar faults that are difficult to distinguish. To solve this problem, a secondary classification fault diagnosis strategy based on PCA-SVM is proposed. The first classification is used to make a preliminary fault diagnosis between all types of faults, the second classification is to make a further diagnosis of the two groups of similar faults. Finally, compared with other fault diagnosis strategies, the proposed strategy improves the accuracy of fault diagnosis.
关键词： Fault Diagnosis,Photovoltaic System,Principal Components Analysis,Cascaded Multilevel Inverter,Support Vector Machine
更新于2025-09-16 10:30:52
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A Fault Diagnosis Strategy Based on Multilevel Classification for a Cascaded Photovoltaic Grid-Connected Inverter
摘要： In this paper, an effective strategy is presented to realize IGBT open-circuit fault diagnosis for closed-loop cascaded photovoltaic (PV) grid-connected inverters. The approach is based on the analysis of the inverter output voltage time waveforms in healthy and faulty conditions. It is mainly composed of two parts. The first part is to select the similar faults based on Euclidean distance and set the specific labels. The second part is the classification based on Principal Component Analysis and Support Vector Machine. The classification is done in two steps. In the first, similar faults are grouped to do the preliminary diagnosis of all fault types. In the second step the similar faults are discriminated. Compared with existing fault diagnosis strategies for several fundamental periods and under different external environments, the proposed strategy has better robustness and higher fault diagnosis accuracy. The effectiveness of the proposed fault diagnosis strategy is assessed through simulation results.
关键词： fault diagnosis,support vector machine,cascaded multilevel inverter,principal components analysis,closed-loop photovoltaic system
更新于2025-09-16 10:30:52
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Theory and Experiment of a Compact Waveguide Polarization Diplexer
摘要： A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA in a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this paper we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.
关键词： radiation effects,fault diagnosis,field programmable gate arrays,Emulation
更新于2025-09-16 10:30:52
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[IEEE 2019 IEEE Energy Conversion Congress and Exposition (ECCE) - Baltimore, MD, USA (2019.9.29-2019.10.3)] 2019 IEEE Energy Conversion Congress and Exposition (ECCE) - A Novel Approximate Model Based Fault Diagnosis Technique for a Photovoltaic DC/AC Grid Tied Inverter
摘要： The recent popularity of the utilization of photovoltaic (PV) systems over conventional power generation has placed focus onto the reliability of support equipment, such as DC-AC inverters. With prolonged use, short-circuit (SC) or open-circuit (OC) faults can develop in the semiconductor devices. This work is proposing a novel fault diagnosis algorithm. The method makes use of the H-bridge inverter approximated as a synchronous switching buck converter while assuming that the grid frequency is much lower than the inverter switching frequency. The proposed algorithm allows detection and identification of SC and OC faults by combining a comparison between the estimated and actual inductor current and the incremental change in the output voltage. To allow continuous functioning of the inverter post fault, a redundant leg is added to the PV inverter. In this PV inverter topology, a fuse is allocated for each switch to prevent overcurrent and a triode for alternating current (TRIAC) is added for each leg to allow isolation of the faulty leg and connection of the redundant leg.
关键词： inverter,short circuit,fault diagnosis,open circuit,fault tolerance
更新于2025-09-12 10:27:22
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On-line Monitoring System Based on Open Source Platform for Photovoltaic Array
摘要： To evaluate the performance of photovoltaic (PV) power plants, it is necessary to effectively monitor PV power plants. An on-line monitoring system based on open-source platform is presented for monitoring and managing the PV power plant effectively and economically. The proposed monitoring system consists of data acquisition, transmission part, data gateway, and on-line monitoring center. A PV diagnosis approach based on FFA-SVM for array fault is implemented in the gateway. The on-line monitoring center based on the platform ubidots is designed for displaying the data and monitoring PV arrays. Experiment results show that the system can realize abundant data visualization and accurate PV fault diagnosis.
关键词： Fault diagnosis,Photovoltaic monitoring,Photovoltaic array,Open-source platform
更新于2025-09-12 10:27:22
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Fault diagnosis method of photovoltaic array based on support vector machine
摘要： Photovoltaic (PV) arrays are prone to various faults due to the hostile working environment. This paper presents the fault diagnosis algorithm based on support vector machine (SVM) to detect short circuit, open circuit, and lack of irradiation faults that occurred in PV arrays. By analyzing these faults and I–V characteristic curves of PV arrays, the short-circuit current, open-circuit voltage, maximum-power current, and maximum-power voltage are chosen as input parameters of SVM-based fault diagnosis algorithm. The data pre-processing methods are used to improve the quality of fault data set considering the effects of the quality on the performance of SVM-based fault diagnosis algorithm. The grid search and k-fold cross-validation methods are proposed to optimize the parameters of the SVM-based fault diagnosis algorithm. It gets test accuracy of 97% by testing the trained SVM-based fault diagnosis algorithm with 400 data. The experimental results indicate that the SVM-based fault diagnosis algorithm has higher accuracy and generalization ability than other algorithm for fault diagnosis of PV arrays.
关键词： k-fold cross-validation,PV arrays,data preprocessing,grid search,SVM-based fault diagnosis algorithm
更新于2025-09-12 10:27:22