As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple lines.Neverthe...As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple lines.Nevertheless,how to choose the appropriate location for the IPFC converters has not been discussed thoroughly.To solve this problem,this paper proposes a novel location method for IPFC using entropy theory.To clarify IPFC’s impact on system power flow,its operation mechanism and control strategies of different types of serial converters are discussed.Subsequently,to clarify the system power flow characteristic suitable for device location analysis,the entropy concept is introduced.In this process,the power flow distribution entropy index is used as an optimization index.Using this index as a foundation,the power flow transfer entropy index is also generated and proposed for the IPFC location determination study.Finally,electromechanical electromagnetic hybrid simulations based on ADPSS are implemented for validation.These are tested in a practical power grid with over 800 nodes.A modular multilevel converter(MMC)-based IPFC electromagnetic model is also established for precise verification.The results show that the proposed method can quickly and efficiently complete optimized IPFC location and support IPFC to determine an optimal adjustment in the N-1 fault cases.展开更多
Design for modem engineering system is becoming multidisciplinary and incorporates practical uncertainties; therefore, it is necessary to synthesize reliability analysis and the multidisciplinary design optimization ...Design for modem engineering system is becoming multidisciplinary and incorporates practical uncertainties; therefore, it is necessary to synthesize reliability analysis and the multidisciplinary design optimization （MDO） techniques for the design of complex engineering system. An advanced first order second moment method-based concurrent subspace optimization approach is proposed based on the comparison and analysis of the existing multidisciplinary optimization techniques and the reliability analysis methods. It is seen through a canard configuration optimization for a three-surface transport that the proposed method is computationally efficient and practical with the least modification to the current deterministic optimization process.展开更多
为改进响应面协同优化(CO-RS,Collaborative Optimization based on ResponseSurface)方法的工程实用性,提出改进的CO-RS方法.在响应面建立中应用广义乘子法和信赖域法,取消响应面更新对梯度的依赖性.针对平流层飞艇的总体设计与优化问...为改进响应面协同优化(CO-RS,Collaborative Optimization based on ResponseSurface)方法的工程实用性,提出改进的CO-RS方法.在响应面建立中应用广义乘子法和信赖域法,取消响应面更新对梯度的依赖性.针对平流层飞艇的总体设计与优化问题,基于改进的CO-RS框架,进行了系统任务分析和学科耦合分析.对气动与推进子系统、结构子系统和能源子系统进行了学科分析,以最小化平流层飞艇的质量为目标,建立基于改进CO-RS框架的多学科设计优化(MDO,Multidisciplinary Design Optimization)模型和相应的学科分析模型.利用iSIGHT软件搭建求解平台,采用改进的CO-RS算法进行仿真计算,并得到合理结果,验证了所建立的MDO模型的合理性和改进的CO-RS算法在平流层飞艇总体设计优化中的有效性.展开更多
The establishment of the analogy theory between optimal control and computational structural mechanics is based on the linear quadratic control problem in optimal control and the substructural chain theory in structur...The establishment of the analogy theory between optimal control and computational structural mechanics is based on the linear quadratic control problem in optimal control and the substructural chain theory in structural mechanics.When the nonlinear optimal control problem is treated by the above theory, especially展开更多
Weight reduction has attracted much attention among ship designers and ship owners.In the present work,based on an improved bi-directional evolutionary structural optimization(BESO) method and surrogate model method,w...Weight reduction has attracted much attention among ship designers and ship owners.In the present work,based on an improved bi-directional evolutionary structural optimization(BESO) method and surrogate model method,we propose a hybrid optimization method for the structural design optimization of beam-plate structures,which covers three optimization levels:dimension optimization,topology optimization and section optimization.The objective of the proposed optimization method is to minimize the weight of design object under a group of constraints.The kernel optimization procedure(KOP) uses BESO to obtain the optimal topology from a ground structure.To deal with beam-plate structures,the traditional BESO method is improved by using cubic box as the unit cell instead of solid unit to construct periodic lattice structure.In the first optimization level,a series of ground structures are generated based on different dimensional parameter combinations,the KOP is performed to all the ground structures,the response surface model of optimal objective values and dimension parameters is created,and then the optimal dimension parameters can be obtained.In the second optimization level,the optimal topology is obtained by using the KOP according to the optimal dimension parameters.In the third optimization level,response surface method(RSM) is used to determine the section parameters.The proposed method is applied to a hatch cover structure design.The locations and shapes of all the structural members are determined from an oversized ground structure.The results show that the proposed method leads to a greater weight saving,compared with the original design and genetic algorithm(GA) based optimization results.展开更多
文摘多学科设计优化(Multidisciplinary design optimization,MDO)方法能够有效解决大规模复杂工程系统的设计问题,为了更好地处理经常遇到的准可分MDO问题,提出了一种基于罚函数的两级交替优化方法(Two-level alternating optimization method based on penaltyfunction,PAO)。PAO基于分解协调策略,首先将准可分MDO问题分解为一个系统级问题和多个子系统级问题,然后通过交替求解达到子系统间的一致性。首次使用PAO方法对整车抗撞性进行设计优化,计算结果验证了该方法的有效。
基金supported by the Natural Science Foundation of Sichuan Province of China(No.2022NSFSC0262)the Fundamental Research Funds for the Central Universities(No.2022SCU12005).
文摘As one of the new generation flexible AC transmission systems(FACTS)devices,the interline power flow controller(IPFC)has the significant advantage of simultaneously regulating the power flow of multiple lines.Nevertheless,how to choose the appropriate location for the IPFC converters has not been discussed thoroughly.To solve this problem,this paper proposes a novel location method for IPFC using entropy theory.To clarify IPFC’s impact on system power flow,its operation mechanism and control strategies of different types of serial converters are discussed.Subsequently,to clarify the system power flow characteristic suitable for device location analysis,the entropy concept is introduced.In this process,the power flow distribution entropy index is used as an optimization index.Using this index as a foundation,the power flow transfer entropy index is also generated and proposed for the IPFC location determination study.Finally,electromechanical electromagnetic hybrid simulations based on ADPSS are implemented for validation.These are tested in a practical power grid with over 800 nodes.A modular multilevel converter(MMC)-based IPFC electromagnetic model is also established for precise verification.The results show that the proposed method can quickly and efficiently complete optimized IPFC location and support IPFC to determine an optimal adjustment in the N-1 fault cases.
基金National Natural Science Foundation of China (10377015)
文摘Design for modem engineering system is becoming multidisciplinary and incorporates practical uncertainties; therefore, it is necessary to synthesize reliability analysis and the multidisciplinary design optimization （MDO） techniques for the design of complex engineering system. An advanced first order second moment method-based concurrent subspace optimization approach is proposed based on the comparison and analysis of the existing multidisciplinary optimization techniques and the reliability analysis methods. It is seen through a canard configuration optimization for a three-surface transport that the proposed method is computationally efficient and practical with the least modification to the current deterministic optimization process.
文摘为改进响应面协同优化(CO-RS,Collaborative Optimization based on ResponseSurface)方法的工程实用性,提出改进的CO-RS方法.在响应面建立中应用广义乘子法和信赖域法,取消响应面更新对梯度的依赖性.针对平流层飞艇的总体设计与优化问题,基于改进的CO-RS框架,进行了系统任务分析和学科耦合分析.对气动与推进子系统、结构子系统和能源子系统进行了学科分析,以最小化平流层飞艇的质量为目标,建立基于改进CO-RS框架的多学科设计优化(MDO,Multidisciplinary Design Optimization)模型和相应的学科分析模型.利用iSIGHT软件搭建求解平台,采用改进的CO-RS算法进行仿真计算,并得到合理结果,验证了所建立的MDO模型的合理性和改进的CO-RS算法在平流层飞艇总体设计优化中的有效性.
文摘The establishment of the analogy theory between optimal control and computational structural mechanics is based on the linear quadratic control problem in optimal control and the substructural chain theory in structural mechanics.When the nonlinear optimal control problem is treated by the above theory, especially
基金the National Natural Science Foundation of China(No.51509033)
文摘Weight reduction has attracted much attention among ship designers and ship owners.In the present work,based on an improved bi-directional evolutionary structural optimization(BESO) method and surrogate model method,we propose a hybrid optimization method for the structural design optimization of beam-plate structures,which covers three optimization levels:dimension optimization,topology optimization and section optimization.The objective of the proposed optimization method is to minimize the weight of design object under a group of constraints.The kernel optimization procedure(KOP) uses BESO to obtain the optimal topology from a ground structure.To deal with beam-plate structures,the traditional BESO method is improved by using cubic box as the unit cell instead of solid unit to construct periodic lattice structure.In the first optimization level,a series of ground structures are generated based on different dimensional parameter combinations,the KOP is performed to all the ground structures,the response surface model of optimal objective values and dimension parameters is created,and then the optimal dimension parameters can be obtained.In the second optimization level,the optimal topology is obtained by using the KOP according to the optimal dimension parameters.In the third optimization level,response surface method(RSM) is used to determine the section parameters.The proposed method is applied to a hatch cover structure design.The locations and shapes of all the structural members are determined from an oversized ground structure.The results show that the proposed method leads to a greater weight saving,compared with the original design and genetic algorithm(GA) based optimization results.
