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Author

Deshu Chen

Bio: Deshu Chen is an academic researcher from Huazhong University of Science and Technology. The author has contributed to research in topics: Fault (power engineering) & Transformer. The author has an hindex of 11, co-authored 34 publications receiving 815 citations.

Papers
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Journal Article•DOI•
TL;DR: In this article, the authors used the instantaneous power of a squirrel cage induction motor to detect the broken rotor bars and eccentricity in the stator line current of the motor and demonstrated the effectiveness of the proposed technique.
Abstract: Broken rotor bars and eccentricity are common faults in squirrel cage induction motors. These two faults usually occur simultaneously. This paper will deal with this kind of mixed fault. It is well known that the characteristic frequency of broken bars in the stator line current of a squirrel cage induction motor is very near to that of the fundamental component. In the spectrum of the stator line current, the characteristic components related to broken rotor bars are always submerged by the fundamental one, and it is difficult to detect the broken bar fault at an early stage. In our work, instantaneous power of the motor is used as the quantity to be monitored. Theoretical analysis indicates that the spectrum of ac level of the spectrum of the instantaneous power is clear from any component at the fundamental supply frequency, and the fault characteristics can be highlighted, which is effective toward the separation of mixed faults and the quantification of the fault extent. Experimental results have demonstrated the effectiveness of the proposed technique.

168 citations

Journal Article•DOI•
TL;DR: In this paper, the possibility of nonoperation of second-harmonic restraint differential protection in the case of internal faults of power transformers was studied and modified schemes for improved operation for internal faults were presented.
Abstract: The possibility of nonoperation of second-harmonic restraint differential protection in the case of internal faults of power transformers was studied. The smaller the setting for harmonic restraint, the longer will likely be the time delay in the operation of the relay. To study this aspect, various internal faults and inrush conditions were tested on a physical model of a three-phase transformer in the laboratory. The data were analyzed by different protection algorithms. Based on the results of these studies, modified schemes for improved operation for internal faults are presented. >

162 citations

Journal Article•DOI•
TL;DR: In this paper, a wavelet-based directional protection scheme was proposed for UHV/EHV transmission line protective relay. But the wavelet singularity detection technique was not used in this paper.
Abstract: A novel wavelet-based directional protection scheme is presented in this paper. Using the theory of wavelet singularity detection as a powerful signal-processing tool, the initial arrival of the traveling wave and its sign can be identified reliably. Characteristics of the proposed directional protection algorithm are analyzed and results of simulation studies are given. The wavelet-based directional protection scheme solves several problems existing in current protective relays and is suitable for use as an ultra high speed UHV/EHV transmission line protective relay.

122 citations

Journal Article•DOI•
TL;DR: In this paper, a nonlinear variable structure stabilizer is proposed for a single machine connected to an infinite bus power system and a multimachine system with multimode oscillations, which gives satisfactory dynamic performance and good robustness.
Abstract: A nonlinear variable structure stabilizer is proposed in this paper. Design of this stabilizer involves the nonlinear transformation technique, the variable structure control technique and linear system theory. Performance of the proposed nonlinear variable structure controller in a single machine connected to an infinite bus power system and a multimachine system with multimode oscillations is simulated. The responses of the system with the proposed stabilizer are compared with those obtained with some other kinds of stabilizers when the system is subjected to a variety of disturbances. Simulation results show that the nonlinear variable structure stabilizer gives satisfactory dynamic performance and good robustness. >

114 citations

Journal Article•DOI•
TL;DR: In this paper, two adaptive stator ground fault protection schemes based on digital techniques are developed, which can automatically track the change of generator operating conditions before a ground fault occurs, compared to conventional third-harmonic voltage schemes.
Abstract: Equivalent circuits based on the actual connection of coil-groups of generators are used to study the characteristics of various generator stator ground fault protection schemes presented in the literature. The evaluation and the comparison of the characteristics of those schemes are given by means of protection coverage-critical resistance curves. Although these schemes are successful in practice, they suffer the disadvantage of low sensitivity, which is strongly related to generator operating conditions. To overcome this disadvantage, two adaptive stator ground fault protection schemes based on digital techniques are developed. Compared to conventional third-harmonic voltage schemes, they can automatically track the change of generator operating conditions before a ground fault occurs. Test results from a digital simulation show that they can keep high sensitivity during all operating conditions. >

56 citations


Cited by
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Journal Article•DOI•
TL;DR: This paper attempts to summarise and review the recent research and developments in diagnostics and prognostics of mechanical systems implementing CBM with emphasis on models, algorithms and technologies for data processing and maintenance decision-making.

3,848 citations

Journal Article•DOI•
TL;DR: A comprehensive review of the PHM field is provided, followed by an introduction of a systematic PHM design methodology, 5S methodology, for converting data to prognostics information, to enable rapid customization and integration of PHM systems for diverse applications.

1,164 citations

Journal Article•DOI•
TL;DR: This paper investigates diagnostic techniques for electrical machines with special reference to induction machines and to papers published in the last ten years, and research activities are classified into four main topics.
Abstract: This paper investigates diagnostic techniques for electrical machines with special reference to induction machines and to papers published in the last ten years. A comprehensive list of references is reported and examined, and research activities classified into four main topics: 1) electrical faults; 2) mechanical faults; 3) signal processing for analysis and monitoring; and 4) artificial intelligence and decision-making techniques.

1,003 citations

Journal Article•DOI•
TL;DR: In this paper, a novel evolutionary algorithm-based approach to optimal design of multimachine power system stabilizers (PSSs) is proposed, which employs the particle swarm optimization (PSO) technique to search for optimal settings of PSS parameters.
Abstract: In this paper, a novel evolutionary algorithm-based approach to optimal design of multimachine power system stabilizers (PSSs) is proposed. The proposed approach employs the particle swarm optimization (PSO) technique to search for optimal settings of PSS parameters. Two elgenvalue-based objective functions to enhance system damping of electromechanical modes are considered. The robustness of the proposed approach to the initial guess is demonstrated. The performance of the proposed PSO-based PSS (PSOPSS) under different disturbances, loading conditions, and system configurations is tested and examined for different multimachine power systems. Eigenvalue analysis and nonlinear simulation results show the effectiveness of the proposed PSOPSSs to damp out the local as well as the interarea modes of oscillations and work effectively over a wide range of loading conditions and system configurations. In addition, the potential and superiority of the proposed approach over the conventional approaches are demonstrated.

684 citations

Journal Article•DOI•
TL;DR: A comprehensive survey of the existing condition monitoring and protection methods in the following five areas: thermal protection and temperature estimation, stator insulation monitoring, bearing fault detection, broken rotor bar/end-ring detection, and air gap eccentricity detection is presented in this article.
Abstract: Medium-voltage (MV) induction motors are widely used in the industry and are essential to industrial processes. The breakdown of these MV motors not only leads to high repair expenses but also causes extraordinary financial losses due to unexpected downtime. To provide reliable condition monitoring and protection for MV motors, this paper presents a comprehensive survey of the existing condition monitoring and protection methods in the following five areas: thermal protection and temperature estimation, stator insulation monitoring and fault detection, bearing fault detection, broken rotor bar/end-ring detection, and air gap eccentricity detection. For each category, the related features of MV motors are discussed; the effectiveness of the existing methods are discussed in terms of their robustness, accuracy, and implementation complexity. Recommendations for the future research in these areas are also presented.

511 citations