To understand the quasi-static and dynamic compressive mechanical behavior of two- dimensional SiC fiber-reinforced SiC composites (2D-SiC1/SiC), their compressive behavior at room temperature was investigated at a ...To understand the quasi-static and dynamic compressive mechanical behavior of two- dimensional SiC fiber-reinforced SiC composites (2D-SiC1/SiC), their compressive behavior at room temperature was investigated at a strain rate from 10-4 to 104/s, and the fracture surfaces and damage morphology were observed. The results show that the dynamic failure strength of 2D-SiC1/SiC obeys the Weibull distribution, and the Weibull modulus is 5,66. Meanwhile, 2D-SiC1/SiC presents a transition from brittle to tough with a decrease of strain rate, and 2D-SiC1/SiC has a more significant strain rate sensitivity compared to the 2D-C/SiC composites. The failure mode of 2D-SiC1/SiC depends upon the strain rate.展开更多
This paper proposes a dynamic-decision-based realtime dispatch method to coordinate the economic objective with multiple types of security dispatch objectives while reducing constraint violations in the process of adj...This paper proposes a dynamic-decision-based realtime dispatch method to coordinate the economic objective with multiple types of security dispatch objectives while reducing constraint violations in the process of adjusting the system operation point to the optimum.In each decision moment,the following tasks are executed in turn:①locally linearizing the system model at the current operation point with the online model identification by using measurements;②narrowing down the gaps between unsatisfied security requirements and their security thresholds in order of priority;③minimizing the generation cost;④minimizing the security indicators within their security thresholds.Compared with the existing real-time dispatch strategies,the proposed method can adjust the deviations caused by unpredictable power flow fluctuations,avoid dispatch bias caused by model parameter errors,and reduce the constraint violations in the dispatch decision process.The effectiveness of the proposed method is verified with the IEEE 39-bus system.展开更多
基金Funded by the Scientific and Technological Development Project of Yantai(No.2013JH020)
文摘To understand the quasi-static and dynamic compressive mechanical behavior of two- dimensional SiC fiber-reinforced SiC composites (2D-SiC1/SiC), their compressive behavior at room temperature was investigated at a strain rate from 10-4 to 104/s, and the fracture surfaces and damage morphology were observed. The results show that the dynamic failure strength of 2D-SiC1/SiC obeys the Weibull distribution, and the Weibull modulus is 5,66. Meanwhile, 2D-SiC1/SiC presents a transition from brittle to tough with a decrease of strain rate, and 2D-SiC1/SiC has a more significant strain rate sensitivity compared to the 2D-C/SiC composites. The failure mode of 2D-SiC1/SiC depends upon the strain rate.
基金This work was supported by the National Natural Science Foundation of China(No.51761145106)the Guangdong Provincial Natural Science Foundation of China(No.2018B030306041)+1 种基金the Fundamental Research Funds for the Central Universities(No.2019SJ01)the China Scholarship Council(No.201806155019).
文摘This paper proposes a dynamic-decision-based realtime dispatch method to coordinate the economic objective with multiple types of security dispatch objectives while reducing constraint violations in the process of adjusting the system operation point to the optimum.In each decision moment,the following tasks are executed in turn:①locally linearizing the system model at the current operation point with the online model identification by using measurements;②narrowing down the gaps between unsatisfied security requirements and their security thresholds in order of priority;③minimizing the generation cost;④minimizing the security indicators within their security thresholds.Compared with the existing real-time dispatch strategies,the proposed method can adjust the deviations caused by unpredictable power flow fluctuations,avoid dispatch bias caused by model parameter errors,and reduce the constraint violations in the dispatch decision process.The effectiveness of the proposed method is verified with the IEEE 39-bus system.