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Energy Management of a Grid-connected High Power Energy Recovery Battery Testing System
Ke Zhang,Bo Long,Cheol-Jung Yoo,Hye-Min Noh,Young-Won Chang 대한전기학회 2016 Journal of Electrical Engineering & Technology Vol.11 No.4
Energy recovery battery testing systems (ERBTS) have been widely used in battery manufactures. All the ERBTS are connected in parallel which forms a special and complicated microgrid system, which has the shortcomings of low energy recovery efficiency, complex grid-connected control algorithms issues for islanded detection, and complicated power circuit topology issues. To solve those shortcomings, a DC micro-grid system is proposed, the released testing energy has the priority to be reutilized between various testing system within the local grid, Compared to conventional scheme, the proposed system has the merits of a simplified power circuit topology, no needs for synchronous control, and much higher testing efficiency. The testing energy can be cycleused inside the local micro-grid. The additional energy can be recovered to AC-grid. Numerous experimental comparison results between conventional and proposed scheme are provided to demonstrate the validity and effectiveness of the proposed technique.
Zhang Zu-Bing,Yin Ning-Na,Long Ji-Ming,Zhang Yong-Ke,Liu Nai-Yong,Zhu Jiaying 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.1
Noorda blitealis (Lepidoptera: Pyraloidea: Crambidae) is a major defoliating pest of Moringa trees. Focusing on its mating and reproduction, here we sequenced and analyzed the transcriptome of its pheromone glands (PGs) with a combination of Illumina sequencing, bioinformatics and phylogenetics approaches, coupled with a genomebased analysis. Transcriptome sequencing led to the yields of approximately 162 million clean reads, which were assembled into 60,578 unigenes and 121,692 transcripts, respectively. From the transcriptome, totally 117 genes encoding eight pheromone biosynthesis enzymes and one pheromone degradation enzyme were identified, 90 of which had complete open reading frames. A comparative analysis between PGs and bodies (removing PGs) revealed a large number of differentially expressed genes, including 79 pheromone biosynthesis and degradation related genes. Of the identified genes, NbliDES12 belonging to the △11 desaturase group was likely to a strong candidate for the desaturation of sex pheromones in N. blitealis, as implied by phylogenetic analyses and expression profiles. Finally and most notably, through genome and transcriptome analyses we discovered, for the first time, a novel aldehyde oxidase 6 (AOX6) group of the superfamily Pyraloidea that have been slightly expanded by gene duplications. Moreover, each orthologous AOX group shared highly conserved gene structure. Together, this current study has characterized the genes associated with sex pheromone biosynthesis and degradation from the PG transcriptome of N. blitealis, and more importantly, identifies a novel AOX group of the Pyraloidea.
Energy Management of a Grid-connected High Power Energy Recovery Battery Testing System
Zhang, Ke,Long, Bo,Yoo, Cheol-Jung,Noh, Hye-Min,Chang, Young-Won The Korean Institute of Electrical Engineers 2016 Journal of Electrical Engineering & Technology Vol.11 No.4
Energy recovery battery testing systems (ERBTS) have been widely used in battery manufactures. All the ERBTS are connected in parallel which forms a special and complicated micro-grid system, which has the shortcomings of low energy recovery efficiency, complex grid-connected control algorithms issues for islanded detection, and complicated power circuit topology issues. To solve those shortcomings, a DC micro-grid system is proposed, the released testing energy has the priority to be reutilized between various testing system within the local grid, Compared to conventional scheme, the proposed system has the merits of a simplified power circuit topology, no needs for synchronous control, and much higher testing efficiency. The testing energy can be cycle-used inside the local micro-grid. The additional energy can be recovered to AC-grid. Numerous experimental comparison results between conventional and proposed scheme are provided to demonstrate the validity and effectiveness of the proposed technique.
Eddy Loss Analysis and Parameter Optimization of the WPT System in Seawater
Zhang, Ke-Han,Zhu, Zheng-Biao,Du, Luo-Na,Song, Bao-Wei The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3
Magnetic resonance wireless power transfer (WPT) in the marine environment can be utilized in many applications. However, energy loss in seawater through eddy loss (EL) is another consideration other than WPT in air. Therefore, the effect of system parameters on electric field intensity (EFI) needs to be measured and ELs calculated to optimize such a system. In this paper, the usually complicated analytical expression of EFI is simplified to the product of frequency, current, coil turns, and a coefficient to analyze the eddy current loss (ECL). Moreover, as the calculation of ECL through volume integral is time-consuming, the equivalent eddy loss impedance (EELI) is proposed to help designers determine the optimum parameters quickly. Then, a power distribution model in seawater is conceived based on the introduction of EELI. An optimization flow chart is also proposed according to this power distribution model, from which a prototype system is developed which can deliver 100 W at 90% efficiency with a gap of 30 mm and a frequency of 107.1 kHz.
Adaptive Observer-based Fast Fault Estimation
Ke Zhang,Bin Jiang,Vincent Cocquempot 제어로봇시스템학회 2008 International Journal of Control, Automation, and Vol.6 No.3
This paper studies the problem of fault estimation using adaptive fault diagnosis observer. A fast adaptive fault estimation (FAFE) approximator is proposed to improve the rapidity of fault estimation. Then based on linear matrix inequality (LMI) technique, a feasible algorithm is explored to solve the designed parameters. Furthermore, an extension to sensor fault case is investigated. Finally, simulation results are presented to illustrate the efficiency of the proposed FAFE methodology.
Ke Wang,Yi Tang,Xiao Zhang,Yang Wang,Chuan-Jin Zhang,Hui Zhang 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.5
A novel open-circuit fault diagnosis method for 3-phase 4-wire 3-level active power filters based on voltage error correlation is proposed in this paper. This method is based on observing the output pole voltage error of the active power filter through two kinds of algorithms. One algorithm is a voltage error analytical algorithm, which derives four output voltage error analytic expressions through the pulse state, current value and dc bus voltage, respectively, assuming that all of the IGBTs of a certain phase come to an OC fault. The other algorithm is a current circuit equation algorithm, which calculates the real-time output voltage error through basic circuit theory. A correlation is introduced to measure the similarity of the output voltage errors between the two algorithms, and OC faults are located by the maximum of the correlations. A FPGA has been chosen to implement the proposed method due to its fast prototyping. Simulation and experimental results are presented to show the performance of the proposed OC fault diagnosis method.
Ke Zhang,Jingyu Wang,Huaitao Shi,Xiaochen Zhang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.4
In the case of large differences in working conditions and large noise effects, how to maintain the similarity of the same fault type is a major difficulty in the rolling bearing fault diagnosis. In addition, variable working conditions will cause the signal take place the local modulation, which makes the signal more susceptible to noise. Most of classification algorithms are difficult to eliminate the influence of variable working conditions on diagnostic results. To solve the problem, a fault diagnosis method is proposed which takes into account the change of speed and load in this paper. The method first applies the synchronous compression wavelet transformation to pre-process the data to reduce the effect of noise on feature extraction. Then, the Triplet loss function is improved and combined with the Hard Samples Mining theory to proposes a new loss function called Quadru-Hard loss to solve the problem of difficult classification under variable working conditions. Based on the experimental analysis of two sets of bearing fault data under variable speeds and variable loads, the results show that the method has a highly accuracy in fault diagnosis under two variable conditions.