2012 International Conference on Renewable Energy Research and Applications (ICRERA)最新文献

{"title":"Basic sensitivity analysis of conversion losses in a DC microgrid","authors":"H. Kakigano, Y. Miura, T. Ise, J. Van Roy, J. Driesen","doi":"10.1109/ICRERA.2012.6477368","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477368","url":null,"abstract":"This paper presents a basic sensitivity analysis of the conversion losses in a dc microgrid by varying the system parameters. A simple residential apartment with 20 units with a photovoltaic (PV) system is taken for the analysis. The conversion losses are calculated with the measured electricity consumption and the estimated output of the PV system. Modelica, an object-oriented modeling language, was used as a simulation tool because of the flexibility in changing the system configuration and parameters. The simulation results show that the efficiencies of the converters in the system are almost directly proportional to the total system losses. Additionally, the rated capacity of the grid converter influenced the total losses linearly. It is also shown that the total rated capacity of the PV system has a relation to the advantages of dc microgrids compared to ac microgrids. These results reveal that the dc microgrid has an advantage regarding the loss reduction under suitable conditions. Additionally, this basic analysis will contribute to the design of system configurations and parameters for new dc microgrids.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134282138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A compact single-phase bidirectional buck-boost-inverter topology","authors":"M. Jang, M. Ciobotaru, V. Agelidis","doi":"10.1109/ICRERA.2012.6477308","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477308","url":null,"abstract":"This paper proposes a single-phase bidirectional buck-boost-inverter topology. The boosting function is achieved by using a wide range of duty cycles based on the front-end buck-boost converter characteristics. The two main switches operate at 20 kHz to generate a unipolar half-cycle sinusoidal waveform. The fundamental frequency switched full-bridge inverter block converts the unipolar output of the buck-boost converter into a full sinusoidal waveform. The proposed topology has several attractive features such as: compact size, bidirectional power flow control capability, single inductor and capacitor, few voltage and current sensors, and low cost. Analysis, simulation, and experimental results from a laboratory prototype are presented to validate the performance of the proposed inverter topology.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115001799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study on the rotor side control of DFIG-based wind turbine during voltage sags without crowbar system","authors":"M. Salles, A. S. Filho, A. Grilo","doi":"10.1109/ICRERA.2012.6477337","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477337","url":null,"abstract":"The connection of wind farms to the electrical power system has increased very fast in the last years requiring the ability of the wind turbines to assist network during voltage sags. Most of the modern wind turbines are based on doubly fed induction generator with a back-to-back power converter connecting the rotor windings to the grid. One limitation of doubly fed induction generator is the operation during grid faults. The rotor side converter can be damage by high currents induced by the stator windings. This article investigates the behavior of the wind farm during voltage sags using 2 different control strategies. The results have indicated that the strategy which the reference currents are calculated to compensate the stator flux variation during voltage sags can avoid overcurrents in the rotor windings, in some cases, without the use of a crowbar system.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115109073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic analysis modeling for reliability increase of IPM-type BLDCM and energy saving under Dynamic Eccentricity—Stator Inter-turn Fault Coupling","authors":"Kyung-tae Kim, Jun-Kyu Park, Byeong-Woo Kim, J. Hur","doi":"10.1109/ICRERA.2012.6477381","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477381","url":null,"abstract":"In this paper, we propose a modeling technique for the classification of the fault frequency components according to the fault state. Further, the optimal rotor design for an increase in reliability of an Interior Permanent Magnet type Brushless DC Motor (IPM type BLDCM) and a rise of the energy saving. For these improvements, fault states such as Dynamic Eccentricity Fault (DEF), Stator Inter-turn Fault (SITF), and their Coupling Faults (CFs) are modeled and analyzed using a nonlinear Finite Element Method (FEM) and Fast Fourier Transform (FFT).","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131917077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"72hr forecast of wind power in Mani̇sa, Turkey by using the WRF model coupled to WindSim","authors":"B. Efe, E. Unal, S. Mentes, T. Ozdemir, Y. Unal, B. Barutcu, E. Tan, Baris Onol, S. Topçu","doi":"10.1109/ICRERA.2012.6477345","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477345","url":null,"abstract":"Wind power forecasting has recently become important to fulfill the increasing demand on energy usage. Two main approaches are applied to the wind power forecasting which can vary from 6 hours to 48 hours. One way is to model the atmosphere dynamically and the other method is to analyze wind speed and direction statistically. Although dynamical models forecast better than statistical models, since the former solves the problem physically, statistical models can be preferable when short term forecasting is needed due to their quick response time. Most of the currently available wind power forecasting systems analyzes the effect of wind field on wind power based on numerical weather prediction models. However, the resolution of these models is not sufficient enough when the scale of the turbines on the wind farms is considered. It is possible to overcome this problem by using computational fluid dynamics (CFD) models, which can provide both linear and nonlinear solutions on the turbine scale in terms of both wind speed and wind power forecasting. In this study, the WRF model is used for 72-hour wind speed and direction forecasting. The initial and boundary conditions of the model are provided by ECMWF operational forecasting data with the resolution of 0.25 degree. The WRF model is downscaled to 1 km resolution over Manisa Soma wind farm and 72-hour forecasts for each day of 2010 are accomplished. WindSim uses wind speed and direction values, which are solved on the nearest grid point of the WRF model to the location of a wind turbine, to simulate high-resolution wind speed values for 72hours. These WRF to WindSim coupled model results are compared to the wind power observations. As a result, we found that daily wind power generation errors per turbine vary between 90kW and 200kW for the seasons of spring, summer, and fall, whereas the error is about 150-350kW for winter. We also compared the errors of 24 hourly model outputs and we found that there is no significant difference among the first, the second, and the third 24 hourly forecasts. We finally applied model output statistics to the WRF to WindSim coupled model results in order to minimize their errors.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132159321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance characteristics of reference modification control DC-DC converter","authors":"H. Maruta, M. Motomura, F. Kurokawa","doi":"10.1109/ICRERA.2012.6477314","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477314","url":null,"abstract":"The purpose of this paper is to show performance characteristics of the reference modification control dc-dc converter which uses neural network and model controls. In the presented method, the neural network controller is used to modify the reference in the proportional control term of the conventional PID control. The neural network controller is repeatedly trained using former predicted data to predict the output voltage. After the training, the reference in the P control is modified by the predictor to reduce the difference of the output voltage and the desired one. This neural network control works to improve the transient response, however, it is difficult to improve transient response greatly when the operation mode across the discontinuous conduction mode and the continuous conduction mode. The model control is adopted simultaneously to ensure the performance from the no-load condition to the full-load condition as the model control is modified the bias term of the PID control in both steady and transient states. As the result, the convergence time of output voltage in the presented method is improved by 83% than the conventional PID control. Furthermore, the undershoot of output voltage is improved by 75% than the conventional PID control.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128091874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and catalytic performance of Y2Ce2−xRuxO7(x=0∼0.4) on autothermal ethanol steam reforming reaction","authors":"Yun-sheng Chen, Chi‐Shen Lee","doi":"10.1109/ICRERA.2012.6477426","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477426","url":null,"abstract":"Pyrochlore phases of Y₂Ce_2-xRu_xO₇ (x=0~0.4) solid solutions were prepared with the sol-gel process and used as catalysts for the autothermal steam reforming of ethanol (AESR). The as-prepared samples were characterized with powder X-ray diffraction (PXRD), X-ray photoelectron spectra (XPS) and temperature-programmed reduction (TPR). The oxidation state of Ru ions was confirmed by XPS and TPR analyses. Tests of catalytic activity showed that the reforming performance of Y₂Ce_2-xRu_xO₇ catalysts was affected by the Ru ion content. The optimized catalyst was Y₂Ce_1.6Ru_0.4O₇ with hydrogen selectivity S_H2 ~98% (autothermal temperature ~700°C and 100% ethanol conversion at C/O = 0.6).","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133800028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new control method in startup progress for a super turbo generator as a shipboard waste heat recovery system","authors":"N. Matsui, T. Matsuo, Y. Ichiki, T. Kanaboshi","doi":"10.1109/ICRERA.2012.6477382","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477382","url":null,"abstract":"This paper presents a new control method for a super-turbo generating (STG) system using an accurate ship-plant system model that ascertains startup characteristics. The STG system is a waste heat recovery type of generation system that makes use of exhaust gas from the main shipboard diesel engines. With STG systems, however, control during startup is not entirely clear. Startup characteristics from the steam turbine and power turbine startup through synchronization to the system bus are ascertained using an accurate simulation model, and the startup sequence control is clarified. As a result, the startup sequence control under consideration facilitates a safe and smooth STG system startup. Synchronization to the system bus is attained, and highly satisfactory results are achieved, while avoiding the risk in actual plant testing.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"21 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133824567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research and development of high-power high-efficiency hall-type ion engines for space exploration","authors":"Y. Mito, T. Ikeda, N. Sugimoto, K. Togawa, H. Tahara","doi":"10.1109/ICRERA.2012.6477454","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477454","url":null,"abstract":"High-power and high-specific-impulse characteristics of Hall thrusters were experimentally studied. Input power and specific impulse reached above 5 kW and 3000 sec, respectively. As a result, the specific impulse and the thrust efficiency were 3202 sec and 61 %, respectively, with 2.8 kW. Discharge current oscillation also increased by raising discharge voltage.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125821431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Power efficiency improvement at light load for POL power supply employing two stage coupled inductor converter","authors":"S. Goto, T. Sato, K. Nishijima, T. Nabeshima","doi":"10.1109/ICRERA.2012.6477392","DOIUrl":"https://doi.org/10.1109/ICRERA.2012.6477392","url":null,"abstract":"This paper proposes a new two-stage converter with a coupling capacitor and a coupled inductor. In order to downsize the two-stage converter, two inductors are tightly coupled together. Circuit operation is described in detail. Steady state analysis is performed and confirmed by experiments. It is clarified that the proposed converter has advantages of larger voltage conversion ratio and higher power efficiency in light load region than a single-stage converter and a conventional two-stage converter. It is also clarified that turns ratio of the coupled inductor must be unity for the safety operation.","PeriodicalId":239142,"journal":{"name":"2012 International Conference on Renewable Energy Research and Applications (ICRERA)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121711009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}