Application of a DFIG （doubly-fed induction generator）, which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supp...Application of a DFIG （doubly-fed induction generator）, which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supply is one of important roles for the gas engine eogeneration system. In the case of conventional constant speed of synchronous generator, the amount of the allowed step load is limited to around 30% of the rated power. On the other hand, DFIG is expected to increase the amount of step load during the stand-alone operation. In this paper, it has been demonstrated that an increase in the gas engine speed resulted in an increase in the maximum amount of step load using experimental equipment with a real gas engine. It has been concluded that the proposed system can improve the performance of an emergency power supply at step-loading.展开更多
Discusses the optimization of machining operation sequencing by simulated annealing, and building a simulated annealing optimization model. From which, a new way to optimize operation sequencing can be developed.
The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displac...The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displacement output characteristics of piezoelectric stacks,the trajectory at the drive foot of stator is firstly produced with two space quadrature piezoelectric actuators excited by sawtooth wave and square wave.Secondly,the friction drive principle of motor is used to analyze the working mechanisms of the continuous stepping motion.Finally,the motor prototype is designed and experiments are carried out.The experimental result shows that the motor can stably operate within the scope of 350 Hz to 750 Hz.When the excitation voltage is 30 Vand pre-load is 3Nor10 N,the lateral amplitude of the drive foot is approximately 4μm and the stable average interval ranges from3.1μm to 3.2μm with the error rate of 5%—7.5%.展开更多
A three-step synthesis strategy for the automatic synthesis of operating procedures in batch processoperations is presented in this paper.The first step is pre-operation which consists of a set of checks that mustbe c...A three-step synthesis strategy for the automatic synthesis of operating procedures in batch processoperations is presented in this paper.The first step is pre-operation which consists of a set of checks that mustbe considered before starting the basic process operation.The second step is operation which is described by a setof basic control instructions.The third step is post-operation described by a set of instructions that must becarried out when the basic process operation is terminated.The three-step synthesis method has been imple-mented as part of a prototype recipe management system.展开更多
脱丁烷塔聚合物结垢问题是制约乙烯装置长周期运行的主要因素之一。目前新建装置通过降低操作压力在防止脱丁烷塔聚合物结垢方面取得了显著效果。以脱丁烷塔为例,对降压过程的可行性、经济性以及风险点进行分析和总结,利用化工流程模拟...脱丁烷塔聚合物结垢问题是制约乙烯装置长周期运行的主要因素之一。目前新建装置通过降低操作压力在防止脱丁烷塔聚合物结垢方面取得了显著效果。以脱丁烷塔为例,对降压过程的可行性、经济性以及风险点进行分析和总结,利用化工流程模拟软件Aspen Plus对降压后各项工艺参数进行模拟优化,将优化结果应用于实际生产过程。结果表明,脱丁烷塔的降压极限为350 kPa,降压后全塔温度降低约4℃,塔釜粗裂解汽油中的C_(4)摩尔分数降低0.32百分点,节省低压蒸汽1.3 t h,装置能耗和C_(4)产品损失降低,循环水侧压降、循环水在换热器内的流速和对数传热温差均在合理范围之内。展开更多
文摘Application of a DFIG （doubly-fed induction generator）, which is one of adjustable speed generators, to a gas engine cogeneration system has been investigated. To operate during a blackout as an emergency power supply is one of important roles for the gas engine eogeneration system. In the case of conventional constant speed of synchronous generator, the amount of the allowed step load is limited to around 30% of the rated power. On the other hand, DFIG is expected to increase the amount of step load during the stand-alone operation. In this paper, it has been demonstrated that an increase in the gas engine speed resulted in an increase in the maximum amount of step load using experimental equipment with a real gas engine. It has been concluded that the proposed system can improve the performance of an emergency power supply at step-loading.
文摘Discusses the optimization of machining operation sequencing by simulated annealing, and building a simulated annealing optimization model. From which, a new way to optimize operation sequencing can be developed.
基金supported by the National Natural Science Foundation of China (Nos.51375224,51405420)the Natural Science Foundation of Jiangsu Province (No.BK20140474)
文摘The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displacement output characteristics of piezoelectric stacks,the trajectory at the drive foot of stator is firstly produced with two space quadrature piezoelectric actuators excited by sawtooth wave and square wave.Secondly,the friction drive principle of motor is used to analyze the working mechanisms of the continuous stepping motion.Finally,the motor prototype is designed and experiments are carried out.The experimental result shows that the motor can stably operate within the scope of 350 Hz to 750 Hz.When the excitation voltage is 30 Vand pre-load is 3Nor10 N,the lateral amplitude of the drive foot is approximately 4μm and the stable average interval ranges from3.1μm to 3.2μm with the error rate of 5%—7.5%.
文摘A three-step synthesis strategy for the automatic synthesis of operating procedures in batch processoperations is presented in this paper.The first step is pre-operation which consists of a set of checks that mustbe considered before starting the basic process operation.The second step is operation which is described by a setof basic control instructions.The third step is post-operation described by a set of instructions that must becarried out when the basic process operation is terminated.The three-step synthesis method has been imple-mented as part of a prototype recipe management system.
文摘脱丁烷塔聚合物结垢问题是制约乙烯装置长周期运行的主要因素之一。目前新建装置通过降低操作压力在防止脱丁烷塔聚合物结垢方面取得了显著效果。以脱丁烷塔为例,对降压过程的可行性、经济性以及风险点进行分析和总结,利用化工流程模拟软件Aspen Plus对降压后各项工艺参数进行模拟优化,将优化结果应用于实际生产过程。结果表明,脱丁烷塔的降压极限为350 kPa,降压后全塔温度降低约4℃,塔釜粗裂解汽油中的C_(4)摩尔分数降低0.32百分点,节省低压蒸汽1.3 t h,装置能耗和C_(4)产品损失降低,循环水侧压降、循环水在换热器内的流速和对数传热温差均在合理范围之内。
