Switched systems play an imperative role in modeling many real industrial systems with abrupt changes.Due to possible exposure to unreliable and complex physical environments,switching dynamics may simultaneously face...Switched systems play an imperative role in modeling many real industrial systems with abrupt changes.Due to possible exposure to unreliable and complex physical environments,switching dynamics may simultaneously face multiple faults,including the unexpected controller disconnect,the temporary mismatch between subsystems and desired corresponding controllers,and the intermittent disordering of mode transitions.These commonly arising faults may result in severe and detrimental impacts on the reliability and convergence of the closed-loop solution,thereby bringing significant yet challenging issues to be tackled.This paper provides the first attempt to investigate the stabilization problem for a class of constrained switched linear systems with multiple faults under mode-dependent dwell time(MDT).From a set-theory perspective,we demonstrate a critical necessary and sufficient stability condition for switched systems without uncertainties.Moreover,the non-conservative stability criterion is further extended to the perturbed switched systems with rigorous proof.A switching communication network example verifies the validity of the theoretical result and demonstrates their advantages.展开更多
This paper aims to fuse two well-established and,at the same time,opposed control techniques,namely,model predictive control(MPC)and active disturbance rejection control(ADRC),to develop a dynamic motion controller fo...This paper aims to fuse two well-established and,at the same time,opposed control techniques,namely,model predictive control(MPC)and active disturbance rejection control(ADRC),to develop a dynamic motion controller for a laser beam steering system.The proposed technique uses the ADRC philosophy to lump disturbances and model uncertainties into a total disturbance.Then,the total disturbance is estimated via a discrete extended state disturbance observer(ESO),and it is used to(1)handle the system constraints in a quadratic optimization problem and(2)injected as a feedforward term to the plant to reject the total disturbance,together with the feedback term obtained by the MPC.The main advantage of the proposed approach is that the MPC is designed based on a straightforward integrator-chain model such that a simple convex optimization problem is performed.Several experiments show the real-time closed-loop performance regarding trajectory tracking and disturbance rejection.Owing to simplicity,the self-contained approach MPC+ESO becomes a Frugal MPC,which is computationally economical,adaptable,efficient,resilient,and suitable for applications where on-board computational resources are limited.展开更多
Dirac's method which itself is for constrained Boson fields and particle systems is followed and developed to treat Dirac fields in light-front coordinates.
In this paper , the unilaterally constrained motions of a large class of rigid bodiessystems are studied both locally and globally. The main conclusion is that locally,such a system bahaves like a particle in a R...In this paper , the unilaterally constrained motions of a large class of rigid bodiessystems are studied both locally and globally. The main conclusion is that locally,such a system bahaves like a particle in a Riemannian manifold with boundary;globally.under the assumption of energy conservation, the system behaves like a billiards system over a Riemannina manifold with boundary展开更多
This work is concerned with identification and nonlinear predictive control method for MIMO Hammerstein systems with constraints. Firstly, an identification method based on steady-state responses and sub-model method ...This work is concerned with identification and nonlinear predictive control method for MIMO Hammerstein systems with constraints. Firstly, an identification method based on steady-state responses and sub-model method is introduced to MIMO Hammerstein system. A modified version of artificial bee colony algorithm is proposed to improve the prediction ability of Hammerstein model. Next, a computationally efficient nonlinear model predictive control algorithm(MGPC) is developed to deal with constrained problem of MIMO system. The identification process and performance of MGPC are shown. Numerical results about a polymerization reactor validate the effectiveness of the proposed method and the comparisons show that MGPC has a better performance than QDMC and basic GPC.展开更多
Using the Faddeev-Jackiw （FJ） quantization method, this paper treats the CP^1nonlinear sigma model with ChernSimons term. The generalized FJ brackets are obtained in the framework of this quantization method, which ...Using the Faddeev-Jackiw （FJ） quantization method, this paper treats the CP^1nonlinear sigma model with ChernSimons term. The generalized FJ brackets are obtained in the framework of this quantization method, which agree with the results obtained by using the Dirac＇s method.展开更多
The recently improved finite order BFT Hamiltonian embedding method is applied to the two dimensional chiral bosons in non-commutative space. It is then systematically converted to a first class constraint model. Perf...The recently improved finite order BFT Hamiltonian embedding method is applied to the two dimensional chiral bosons in non-commutative space. It is then systematically converted to a first class constraint model. Performing the momentum integrations, the corresponding fully gauge symmetry Lagrangian as well as its partition function in phase space are obtained.展开更多
This work is aimed to rigorously manage voltage saturation and maximum current constraints in Shunt Active Filters. In this respect, assuming 'unconstrained' control algorithms have already been defined to ach...This work is aimed to rigorously manage voltage saturation and maximum current constraints in Shunt Active Filters. In this respect, assuming 'unconstrained' control algorithms have already been defined to achieve standard objectives for such devices(i.e. current tracking for harmonic compensation and DC-bus voltage boundness), a plug-in unit, oriented to extend the system operating region and at the same time preserving good performance under large transients and overload conditions, is presented.This solution allows to improve availability, robustness and composability of Shunt Active Filters, which are expected to be key features in present and next generation complex and possibly 'smart' power grids. The proposed unit is composed by two parts.First, a suitable anti-windup strategy is defined in order to deal with control input saturation. Its main purpose is to preserve the original 'unconstrained error dynamics', in face of input saturation, while guaranteeing low computational burden and reduced performance impairment(the latter goal, in harmonic compensation context, leads to rather non-standard problem formulation).To this aim, the anti-windup acts on the current references through a suitably-designed additional dynamics. Then, in order to cope with current limitations, an additional strategy has been designed; again the current references is suitably shaped to comply with the features and bounds of the system, augmented with the above-mentioned anti-windup solution. The proposed scheme can be simply joined to any kind of unconstrained controller adopted to steer Shunt Active Filters. In this work, an Internal-Model-based current controller is adopted as a benchmark case. The proposed approach is validate through extensive simulation tests.展开更多
A min-max model predictive control strategy is proposed for a class of constrained nonlinear system whose trajectories can be embedded within those of a bank of linear parameter varying （LPV） models. The embedding L...A min-max model predictive control strategy is proposed for a class of constrained nonlinear system whose trajectories can be embedded within those of a bank of linear parameter varying （LPV） models. The embedding LPV models can yield much better approximation of the nonlinear system dynamics than a single LTV model. For each LPV model, a parameter-dependent Lyapunov function is introduced to obtain poly-quadratically stable control law and to guarantee the feasibility and stability of the origi- nal nonlinear system. This approach can greatly reduce computational burden in traditional nonlinear predictive control strategy. Finally a simulation example illustrating the strategy is presented.展开更多
The extended canonical Noether identities and canonical first Noether theorem derived from an extended action in phase space for a system with a singular Lagrangian are formulated. Using these canonical Noether identi...The extended canonical Noether identities and canonical first Noether theorem derived from an extended action in phase space for a system with a singular Lagrangian are formulated. Using these canonical Noether identities,it can be shown that the constraint multipliers connected with the first-class constraints may not be independent, so a query to a conjecture of Dirac is presented. Based on the symmetry properties of the constrained Hamiltonian system in phase space, a counterexample to a conjecture of Dirac is given to show that Dirac's conjecture fails in such a system.We present here a different way rather than Cawley's examples and other's ones in that there is no linearization of constraints in the problem. This example has a feature that neither the primary first-class constraints nor secondary first-class constraints are generators of the gauge transformation.展开更多
By using the Faddeev Senjanovic path integral quantization method, we quantize the composite fermions in quantum electrodynamics （QED）. In the sense of Dirac＇s conjecture, we deduce all the constraints and give Di...By using the Faddeev Senjanovic path integral quantization method, we quantize the composite fermions in quantum electrodynamics （QED）. In the sense of Dirac＇s conjecture, we deduce all the constraints and give Dirac＇s gauge transformations （DGT）. According to that the effective action is invariant under the DGT, we obtain the Noether theorem at the quantum level, which shows the fractional charges for tile composite fermions in QBD. This result is better than the one deduced from the equations of motion for the statistical potentials, because this result contains both odd and even fractional numbers. Purthermore, we deduce the Noether theorem from the invariance of the effective action under the rotational transformations in 2-dimensional （x, y） plane. The result shows that the composite fermions have fractional spins and fractional statistics. These anomalous properties are given by the constraints for the statistical gauge potential.展开更多
In this paper,we define arbitrarily high-order energy-conserving methods for Hamilto-nian systems with quadratic holonomic constraints.The derivation of the methods is made within the so-called line integral framework...In this paper,we define arbitrarily high-order energy-conserving methods for Hamilto-nian systems with quadratic holonomic constraints.The derivation of the methods is made within the so-called line integral framework.Numerical tests to illustrate the theoretical findings are presented.展开更多
基金supported in part by the Natural Sciences and Engineering Research Council of Canada(NSERC)supported by the National Natural Science Foundation of China under Grant 62303403Zhejiang Provincial Natural Science Foundation of China under Grants LR25F030004 and LQ24F030022。
文摘Switched systems play an imperative role in modeling many real industrial systems with abrupt changes.Due to possible exposure to unreliable and complex physical environments,switching dynamics may simultaneously face multiple faults,including the unexpected controller disconnect,the temporary mismatch between subsystems and desired corresponding controllers,and the intermittent disordering of mode transitions.These commonly arising faults may result in severe and detrimental impacts on the reliability and convergence of the closed-loop solution,thereby bringing significant yet challenging issues to be tackled.This paper provides the first attempt to investigate the stabilization problem for a class of constrained switched linear systems with multiple faults under mode-dependent dwell time(MDT).From a set-theory perspective,we demonstrate a critical necessary and sufficient stability condition for switched systems without uncertainties.Moreover,the non-conservative stability criterion is further extended to the perturbed switched systems with rigorous proof.A switching communication network example verifies the validity of the theoretical result and demonstrates their advantages.
基金support through his Master scholarshipThe Vicerrectoría de Investigación y Estudios de Posgrado(VIEP-BUAP)partially funded this work under grant number 00593-PV/2025.
文摘This paper aims to fuse two well-established and,at the same time,opposed control techniques,namely,model predictive control(MPC)and active disturbance rejection control(ADRC),to develop a dynamic motion controller for a laser beam steering system.The proposed technique uses the ADRC philosophy to lump disturbances and model uncertainties into a total disturbance.Then,the total disturbance is estimated via a discrete extended state disturbance observer(ESO),and it is used to(1)handle the system constraints in a quadratic optimization problem and(2)injected as a feedforward term to the plant to reject the total disturbance,together with the feedback term obtained by the MPC.The main advantage of the proposed approach is that the MPC is designed based on a straightforward integrator-chain model such that a simple convex optimization problem is performed.Several experiments show the real-time closed-loop performance regarding trajectory tracking and disturbance rejection.Owing to simplicity,the self-contained approach MPC+ESO becomes a Frugal MPC,which is computationally economical,adaptable,efficient,resilient,and suitable for applications where on-board computational resources are limited.
文摘Dirac's method which itself is for constrained Boson fields and particle systems is followed and developed to treat Dirac fields in light-front coordinates.
文摘In this paper , the unilaterally constrained motions of a large class of rigid bodiessystems are studied both locally and globally. The main conclusion is that locally,such a system bahaves like a particle in a Riemannian manifold with boundary;globally.under the assumption of energy conservation, the system behaves like a billiards system over a Riemannina manifold with boundary
基金Projects(61573052,61273132)supported by the National Natural Science Foundation of China
文摘This work is concerned with identification and nonlinear predictive control method for MIMO Hammerstein systems with constraints. Firstly, an identification method based on steady-state responses and sub-model method is introduced to MIMO Hammerstein system. A modified version of artificial bee colony algorithm is proposed to improve the prediction ability of Hammerstein model. Next, a computationally efficient nonlinear model predictive control algorithm(MGPC) is developed to deal with constrained problem of MIMO system. The identification process and performance of MGPC are shown. Numerical results about a polymerization reactor validate the effectiveness of the proposed method and the comparisons show that MGPC has a better performance than QDMC and basic GPC.
文摘Using the Faddeev-Jackiw （FJ） quantization method, this paper treats the CP^1nonlinear sigma model with ChernSimons term. The generalized FJ brackets are obtained in the framework of this quantization method, which agree with the results obtained by using the Dirac＇s method.
文摘The recently improved finite order BFT Hamiltonian embedding method is applied to the two dimensional chiral bosons in non-commutative space. It is then systematically converted to a first class constraint model. Performing the momentum integrations, the corresponding fully gauge symmetry Lagrangian as well as its partition function in phase space are obtained.
文摘This work is aimed to rigorously manage voltage saturation and maximum current constraints in Shunt Active Filters. In this respect, assuming 'unconstrained' control algorithms have already been defined to achieve standard objectives for such devices(i.e. current tracking for harmonic compensation and DC-bus voltage boundness), a plug-in unit, oriented to extend the system operating region and at the same time preserving good performance under large transients and overload conditions, is presented.This solution allows to improve availability, robustness and composability of Shunt Active Filters, which are expected to be key features in present and next generation complex and possibly 'smart' power grids. The proposed unit is composed by two parts.First, a suitable anti-windup strategy is defined in order to deal with control input saturation. Its main purpose is to preserve the original 'unconstrained error dynamics', in face of input saturation, while guaranteeing low computational burden and reduced performance impairment(the latter goal, in harmonic compensation context, leads to rather non-standard problem formulation).To this aim, the anti-windup acts on the current references through a suitably-designed additional dynamics. Then, in order to cope with current limitations, an additional strategy has been designed; again the current references is suitably shaped to comply with the features and bounds of the system, augmented with the above-mentioned anti-windup solution. The proposed scheme can be simply joined to any kind of unconstrained controller adopted to steer Shunt Active Filters. In this work, an Internal-Model-based current controller is adopted as a benchmark case. The proposed approach is validate through extensive simulation tests.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 60774015, 60825302, 60674018)the National High-Tech Research& Development Program of China (Grant No. 2007AA041403)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Educationof China (Grant No. 20060248001)Shanghai Natural Science Foundation (Grant No. 07JC14016)
文摘A min-max model predictive control strategy is proposed for a class of constrained nonlinear system whose trajectories can be embedded within those of a bank of linear parameter varying （LPV） models. The embedding LPV models can yield much better approximation of the nonlinear system dynamics than a single LTV model. For each LPV model, a parameter-dependent Lyapunov function is introduced to obtain poly-quadratically stable control law and to guarantee the feasibility and stability of the origi- nal nonlinear system. This approach can greatly reduce computational burden in traditional nonlinear predictive control strategy. Finally a simulation example illustrating the strategy is presented.
文摘The extended canonical Noether identities and canonical first Noether theorem derived from an extended action in phase space for a system with a singular Lagrangian are formulated. Using these canonical Noether identities,it can be shown that the constraint multipliers connected with the first-class constraints may not be independent, so a query to a conjecture of Dirac is presented. Based on the symmetry properties of the constrained Hamiltonian system in phase space, a counterexample to a conjecture of Dirac is given to show that Dirac's conjecture fails in such a system.We present here a different way rather than Cawley's examples and other's ones in that there is no linearization of constraints in the problem. This example has a feature that neither the primary first-class constraints nor secondary first-class constraints are generators of the gauge transformation.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11047020 and 11047173)the Natural Science Foundation of Shandong Province, China (Grant Nos. ZR2011AM019, ZR2010AQ025, BS2010DS006, and Y200814)the Scientific and Technological Development Project of Shandong Province, China (Grant No. J08LI56)
文摘By using the Faddeev Senjanovic path integral quantization method, we quantize the composite fermions in quantum electrodynamics （QED）. In the sense of Dirac＇s conjecture, we deduce all the constraints and give Dirac＇s gauge transformations （DGT）. According to that the effective action is invariant under the DGT, we obtain the Noether theorem at the quantum level, which shows the fractional charges for tile composite fermions in QBD. This result is better than the one deduced from the equations of motion for the statistical potentials, because this result contains both odd and even fractional numbers. Purthermore, we deduce the Noether theorem from the invariance of the effective action under the rotational transformations in 2-dimensional （x, y） plane. The result shows that the composite fermions have fractional spins and fractional statistics. These anomalous properties are given by the constraints for the statistical gauge potential.
文摘In this paper,we define arbitrarily high-order energy-conserving methods for Hamilto-nian systems with quadratic holonomic constraints.The derivation of the methods is made within the so-called line integral framework.Numerical tests to illustrate the theoretical findings are presented.
