Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power ...Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power quality classification techniques focused on single power quality events and did not include an optimal feature selection process. This paper presents a classification system that employs Wavelet Transform and the RMS profile to extract the main features of the measured waveforms containing either single or complex disturbances. A data mining process is designed to select the optimal set of features that better describes each disturbance present in the waveform. Support Vector Machine binary classifiers organized in a “One Vs Rest” architecture are individually optimized to classify single and complex disturbances. The parameters that rule the performance of each binary classifier are also individually adjusted using a grid search algorithm that helps them achieve optimal performance. This specialized process significantly improves the total classification accuracy. Several single and complex disturbances were simulated in order to train and test the algorithm. The results show that the classifier is capable of identifying >99% of single disturbances and >97% of complex disturbances.展开更多
Combined cycle plants (CCs) are broadly used all over the world. The inclusion of CCs into the optimal resource scheduling causes difficulties because they can be operated in different operating configuration modes ba...Combined cycle plants (CCs) are broadly used all over the world. The inclusion of CCs into the optimal resource scheduling causes difficulties because they can be operated in different operating configuration modes based on the number of combustion and steam turbines. In this paper a model CCs based on a mixed integer linear programming approach to be included into an optimal short term resource optimization problem is presented. The proposed method allows modeling of CCs in different modes of operation taking into account the non convex operating costs for the different combined cycle mode of operation.展开更多
Abstract Here,we provide a status update of an integrated gasification fuel cell(IGFC)power-generation system being developed at the National Institute of Clean-and-Low-Carbon in China at the megawatt thermal(MWth)sca...Abstract Here,we provide a status update of an integrated gasification fuel cell(IGFC)power-generation system being developed at the National Institute of Clean-and-Low-Carbon in China at the megawatt thermal(MWth)scale.This system is designed to use coal as fuel to produce syngas as a first step,similar to that employed for the integrated gasification combined cycle.Subsequently,the solid-oxide fuel-cell(SOFC)system is used to convert chemical energy to electricity directly through an electrochemical reaction without combustion.This system leads to higher efficiency as compared with that from a traditional coal-fired power plant.The unreacted fuel in the SOFC system is transported to an oxygencombustor to be converted to steam and carbon dioxide(CO_(2)).Through a heat-recovery system,the steam is condensed and removed,and CO_(2) is enriched and captured for sequestration or utilization.Comprehensive economic analyses for a typical IGFC system was performed and the results were compared with those for a supercritical pulverized coal-fired power plant.The SOFC stacks selected for IGFC development were tested and qualified under hydrogen and simulated coal syngas fuel.Experimental results using SOFC stacks and thermodynamic analyses indicated that the control of hydrogen/CO ratio of syngas and steam/CO ratio is important to avoid carbon deposition with the fuel pipe.A 20-kW SOFC unit is under development with design power output of 20 kW and DC efficiency of 50.41%.A 100 kW-level subsystem will consist of 6920-kW power-generation units,and the MWth IGFC system will consist of 59100 kWlevel subsystems.展开更多
The Bioprocessing industry delivers high-value protein-based pharmaceutical products produced using microbial or animal cells. Animal cell culture, the only method currently available for the production of proteins wi...The Bioprocessing industry delivers high-value protein-based pharmaceutical products produced using microbial or animal cells. Animal cell culture, the only method currently available for the production of proteins with human-like post-translational modifications, is an expensive and labor-intensive process, as animal cells have complex nutrient requirements. Optimization studies have typically been limited to experimental studies, although there has recently been increased interest in combined experimental and computational approaches. In this work, we present the results of a dynamic optimization approach to improving animal cell bioprocesses. We have based this on a model validated over batch and fed-batch conditions and have examined four possible objective functions. Our results indicate that the maximization of the product concentration or the integral of viable cell concentration over time give equivalent results and can improve the product titer up to 70% over non-optimized fed-batch cultures.展开更多
文摘Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power quality classification techniques focused on single power quality events and did not include an optimal feature selection process. This paper presents a classification system that employs Wavelet Transform and the RMS profile to extract the main features of the measured waveforms containing either single or complex disturbances. A data mining process is designed to select the optimal set of features that better describes each disturbance present in the waveform. Support Vector Machine binary classifiers organized in a “One Vs Rest” architecture are individually optimized to classify single and complex disturbances. The parameters that rule the performance of each binary classifier are also individually adjusted using a grid search algorithm that helps them achieve optimal performance. This specialized process significantly improves the total classification accuracy. Several single and complex disturbances were simulated in order to train and test the algorithm. The results show that the classifier is capable of identifying >99% of single disturbances and >97% of complex disturbances.
文摘Combined cycle plants (CCs) are broadly used all over the world. The inclusion of CCs into the optimal resource scheduling causes difficulties because they can be operated in different operating configuration modes based on the number of combustion and steam turbines. In this paper a model CCs based on a mixed integer linear programming approach to be included into an optimal short term resource optimization problem is presented. The proposed method allows modeling of CCs in different modes of operation taking into account the non convex operating costs for the different combined cycle mode of operation.
基金The authors thank the Ministry of Science and Technology of the People’s Republic of China for financial support under contract of 2017YEB061900。
文摘Abstract Here,we provide a status update of an integrated gasification fuel cell(IGFC)power-generation system being developed at the National Institute of Clean-and-Low-Carbon in China at the megawatt thermal(MWth)scale.This system is designed to use coal as fuel to produce syngas as a first step,similar to that employed for the integrated gasification combined cycle.Subsequently,the solid-oxide fuel-cell(SOFC)system is used to convert chemical energy to electricity directly through an electrochemical reaction without combustion.This system leads to higher efficiency as compared with that from a traditional coal-fired power plant.The unreacted fuel in the SOFC system is transported to an oxygencombustor to be converted to steam and carbon dioxide(CO_(2)).Through a heat-recovery system,the steam is condensed and removed,and CO_(2) is enriched and captured for sequestration or utilization.Comprehensive economic analyses for a typical IGFC system was performed and the results were compared with those for a supercritical pulverized coal-fired power plant.The SOFC stacks selected for IGFC development were tested and qualified under hydrogen and simulated coal syngas fuel.Experimental results using SOFC stacks and thermodynamic analyses indicated that the control of hydrogen/CO ratio of syngas and steam/CO ratio is important to avoid carbon deposition with the fuel pipe.A 20-kW SOFC unit is under development with design power output of 20 kW and DC efficiency of 50.41%.A 100 kW-level subsystem will consist of 6920-kW power-generation units,and the MWth IGFC system will consist of 59100 kWlevel subsystems.
文摘The Bioprocessing industry delivers high-value protein-based pharmaceutical products produced using microbial or animal cells. Animal cell culture, the only method currently available for the production of proteins with human-like post-translational modifications, is an expensive and labor-intensive process, as animal cells have complex nutrient requirements. Optimization studies have typically been limited to experimental studies, although there has recently been increased interest in combined experimental and computational approaches. In this work, we present the results of a dynamic optimization approach to improving animal cell bioprocesses. We have based this on a model validated over batch and fed-batch conditions and have examined four possible objective functions. Our results indicate that the maximization of the product concentration or the integral of viable cell concentration over time give equivalent results and can improve the product titer up to 70% over non-optimized fed-batch cultures.