Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been w...Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been widely used. An approach that combines differential evolution （DE） algorithm and control vector parameteri- zation （CVP） is proposed in this paper. In the proposed CVP, control variables are approximated with polynomials based on state variables and time in the entire time interval. Region reduction strategy is used in DE to reduce the width of the search region, which improves the computing efficiency. The results of the case studies demonstrate the feasibility and efficiency of the oroposed methods.展开更多
Using the Hamiltonian function method, this paper proposes a family of robust adaptive excitation con- trollers for synchronous generators with steam valve control. First, a parameterization method of robust adaptive ...Using the Hamiltonian function method, this paper proposes a family of robust adaptive excitation con- trollers for synchronous generators with steam valve control. First, a parameterization method of robust adaptive controllers is investigated for dissipative Hamiltonian systems. This method avoids solving Hamilton-Jacobi-Issacs inequalities. The parameters in the family of controllers thus obtained are determined by a locally positive semidefinite function, which has only 2n independent variables, twice as many as the one used to characterize the state feedback. Then, with the parame- terization method and the structural properties of dissipative Hamiltonian systems, a family of robust adaptive excitation controllers is designed for synchronous generators with steam valve control, disturbances and unknown parameters. Simu- lations illustrate the effectiveness and feasibility of the excitation control strategy proposed in the paper.展开更多
基金Supported by the Major State Basic Research Development Program of China(2012CB720500)the National Natural Science Foundation of China(Key Program:U1162202)+2 种基金the National Science Fund for Outstanding Young Scholars(61222303)the National Natural Science Foundation of China(61174118,21206037)Shanghai Leading Academic Discipline Project(B504)
文摘Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been widely used. An approach that combines differential evolution （DE） algorithm and control vector parameteri- zation （CVP） is proposed in this paper. In the proposed CVP, control variables are approximated with polynomials based on state variables and time in the entire time interval. Region reduction strategy is used in DE to reduce the width of the search region, which improves the computing efficiency. The results of the case studies demonstrate the feasibility and efficiency of the oroposed methods.
基金supported by the National Key Basic Research Project of China (No.2004CB318000)the National Natural Science Foundation of China (No.10571095)
文摘Using the Hamiltonian function method, this paper proposes a family of robust adaptive excitation con- trollers for synchronous generators with steam valve control. First, a parameterization method of robust adaptive controllers is investigated for dissipative Hamiltonian systems. This method avoids solving Hamilton-Jacobi-Issacs inequalities. The parameters in the family of controllers thus obtained are determined by a locally positive semidefinite function, which has only 2n independent variables, twice as many as the one used to characterize the state feedback. Then, with the parame- terization method and the structural properties of dissipative Hamiltonian systems, a family of robust adaptive excitation controllers is designed for synchronous generators with steam valve control, disturbances and unknown parameters. Simu- lations illustrate the effectiveness and feasibility of the excitation control strategy proposed in the paper.
