This paper is concerned with fundamental properties of a class of composite systems with fractional degree generalized frequency variables, including controllability, observability and stability. Firstly, some necessa...This paper is concerned with fundamental properties of a class of composite systems with fractional degree generalized frequency variables, including controllability, observability and stability. Firstly, some necessary and sufficient conditions are given to guarantee controllability and observability of such composite systems. Then we prove that the stability problem of such composite systems can be reduced to judging whether a fractional degree polynomial is stable. Finally, the stability analysis result is applied in the supervisory control of fractional-order multi-agent systems, and an example is provided to illustrate the effectiveness of the proposed methods.展开更多
This paper focuscs on the recent progress in the adoption of active disturbance rejection control(ADRC)in thermal pro-cesses as a viable alternative to proportional-_integral-derivative(PID),especially in coa-fired po...This paper focuscs on the recent progress in the adoption of active disturbance rejection control(ADRC)in thermal pro-cesses as a viable alternative to proportional-_integral-derivative(PID),especially in coa-fired power plants.The profound interpretation of this paradigm shift,with backward compatibility,is discussed in detail.A few fundamental issues associated with ADRC's applications in thermal processes are discussed,such as implementation,tuning,and the structural changes.Examples and case studies are presented,encompassing coal-fired power plants,gas turbines and nuclear power plants,as well as highlighting results of field applications.Also discussed are future research opportunities brought by ADRC's entry as the baseline control technology in thermal processes.展开更多
I.INTRODUCTION FRACTIONAL calculus has been applied in all MAD(modeling,analysis and design)aspects of control systems engineering since Shunji Manabe’s pioneering work in early 1960s.The 2016 International Conferenc...I.INTRODUCTION FRACTIONAL calculus has been applied in all MAD(modeling,analysis and design)aspects of control systems engineering since Shunji Manabe’s pioneering work in early 1960s.The 2016 International Conference on Fractional Differentiation and Its Applications(ICFDA)was held in Novi Sad,Serbia,July 18-20.Quoting from the展开更多
Motivated by the experimental result of an electronic circuit element"fractor",we introduce the concept of a dynamic-order fractional dynamic system,in which the differential-order of a fractional dynamic sy...Motivated by the experimental result of an electronic circuit element"fractor",we introduce the concept of a dynamic-order fractional dynamic system,in which the differential-order of a fractional dynamic system is determined by the output signal of another dynamic system.The concept offers an explanation for the physical mechanism of variable-order fractional dynamic systems and multi-system interaction.The properties and potential applications of dynamic-order fractional dynamic systems are further explored by analyzing anomalous relaxation and diffusion processes.展开更多
I.INTRODUCTION FRACTIONAL calculus is about differentiation and integration of non-integer orders.Using integer-order models and controllers for complex natural or man-made systems is simply for our own convenience wh...I.INTRODUCTION FRACTIONAL calculus is about differentiation and integration of non-integer orders.Using integer-order models and controllers for complex natural or man-made systems is simply for our own convenience while the nature runs in a fractional order dynamical way.Using integer order traditiona tools for modelling and control of dynamic systems may resul in suboptimum performance,that is,using fractional order calculus tools,we could be'more optimal'as already doc-展开更多
Mechanical response and simulation for constitutive equation with distributed order derivatives were considered.We investigated the creep compliance,creep recovery,relaxation modulus,stress–strain behavior under harm...Mechanical response and simulation for constitutive equation with distributed order derivatives were considered.We investigated the creep compliance,creep recovery,relaxation modulus,stress–strain behavior under harmonic deformation for each case of two constitutive equations.We express these responses and results as easily computable forms and simulate them by using MATHEMATICA 8.The results involve the exponential integral function,convergent improper integrals on the infinite interval(0,+∞)and the numerical integral method for the convolution integral.For both equations,stress responses to harmonic deformation display hysteresis phenomena and energy dissipation.The two constitutive equations characterize viscoelastic models of fluid-like and solid-like,respectively.展开更多
基金supported by Foundation of Shanxi Scholarship Council(2016-075)Natural Science Foundation of Shanxi Normal University(ZR1601)Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(2018-25)
文摘This paper is concerned with fundamental properties of a class of composite systems with fractional degree generalized frequency variables, including controllability, observability and stability. Firstly, some necessary and sufficient conditions are given to guarantee controllability and observability of such composite systems. Then we prove that the stability problem of such composite systems can be reduced to judging whether a fractional degree polynomial is stable. Finally, the stability analysis result is applied in the supervisory control of fractional-order multi-agent systems, and an example is provided to illustrate the effectiveness of the proposed methods.
基金This work was supported by the Science&Technology Research Project in Henan Province of China(No.212102311052)the National Key Research and Development Program of China(No.2016YFB0901405)the National Natural Science Foundation of China(No.61473265).
文摘This paper focuscs on the recent progress in the adoption of active disturbance rejection control(ADRC)in thermal pro-cesses as a viable alternative to proportional-_integral-derivative(PID),especially in coa-fired power plants.The profound interpretation of this paradigm shift,with backward compatibility,is discussed in detail.A few fundamental issues associated with ADRC's applications in thermal processes are discussed,such as implementation,tuning,and the structural changes.Examples and case studies are presented,encompassing coal-fired power plants,gas turbines and nuclear power plants,as well as highlighting results of field applications.Also discussed are future research opportunities brought by ADRC's entry as the baseline control technology in thermal processes.
文摘I.INTRODUCTION FRACTIONAL calculus has been applied in all MAD(modeling,analysis and design)aspects of control systems engineering since Shunji Manabe’s pioneering work in early 1960s.The 2016 International Conference on Fractional Differentiation and Its Applications(ICFDA)was held in Novi Sad,Serbia,July 18-20.Quoting from the
基金the National Natural Science Foundation of China under Grant No 11202066the National Basic Research Program of China under Grant No 2010CB832702the R&D Special Fund for Public Welfare Industry(Hydrodynamics,Project No 201101014).
文摘Motivated by the experimental result of an electronic circuit element"fractor",we introduce the concept of a dynamic-order fractional dynamic system,in which the differential-order of a fractional dynamic system is determined by the output signal of another dynamic system.The concept offers an explanation for the physical mechanism of variable-order fractional dynamic systems and multi-system interaction.The properties and potential applications of dynamic-order fractional dynamic systems are further explored by analyzing anomalous relaxation and diffusion processes.
文摘I.INTRODUCTION FRACTIONAL calculus is about differentiation and integration of non-integer orders.Using integer-order models and controllers for complex natural or man-made systems is simply for our own convenience while the nature runs in a fractional order dynamical way.Using integer order traditiona tools for modelling and control of dynamic systems may resul in suboptimum performance,that is,using fractional order calculus tools,we could be'more optimal'as already doc-
基金the Natural Science Foundation of Shanghai(No.14ZR1440800)the Course Construction Project of Shanghai Municipal Education Commission(No.33210M161020).
文摘Mechanical response and simulation for constitutive equation with distributed order derivatives were considered.We investigated the creep compliance,creep recovery,relaxation modulus,stress–strain behavior under harmonic deformation for each case of two constitutive equations.We express these responses and results as easily computable forms and simulate them by using MATHEMATICA 8.The results involve the exponential integral function,convergent improper integrals on the infinite interval(0,+∞)and the numerical integral method for the convolution integral.For both equations,stress responses to harmonic deformation display hysteresis phenomena and energy dissipation.The two constitutive equations characterize viscoelastic models of fluid-like and solid-like,respectively.
