This article presents a distributed periodic eventtriggered(PET)optimal control scheme to achieve generation cost minimization and average bus voltage regulation in DC microgrids.In order to accommodate the generation...This article presents a distributed periodic eventtriggered(PET)optimal control scheme to achieve generation cost minimization and average bus voltage regulation in DC microgrids.In order to accommodate the generation constraints of the distributed generators(DGs),a virtual incremental cost is firstly designed,based on which an optimality condition is derived to facilitate the control design.To meet the discrete-time(DT)nature of modern control systems,the optimal controller is directly developed in the DT domain.Afterward,to reduce the communication requirement among the controllers,a distributed event-triggered mechanism is introduced for the DT optimal controller.The event-triggered condition is detected periodically and therefore naturally avoids the Zeno phenomenon.The closed-loop system stability is proved by the Lyapunov synthesis for switched systems.The generation cost minimization and average bus voltage regulation are obtained at the equilibrium point.Finally,switch-level microgrid simulations validate the performance of the proposed optimal controller.展开更多
This paper is focused on a distributed optimal control design for a class of nonlinear timedelay systems with delayed measurements and communication disruptions.The innovation lies in three aspects.The distributed opt...This paper is focused on a distributed optimal control design for a class of nonlinear timedelay systems with delayed measurements and communication disruptions.The innovation lies in three aspects.The distributed optimal control method which includes an optimal controller and a bounded controller is designed based on Lyapunov function.The availability of data transmitted through the communication channel depends on a feasibility problem.And a sufficient condition to guarantee ultimate boundedness of the system is given based on appropriate assumptions.The significance of this paper is that this distributed optimal control method is applied to time-delay system.Finally,a simulation example is given to verify the effectiveness of the proposed method.展开更多
The power loss minimization and DC voltage stability of the multi-terminal direct current(MTDC)system with large-scale wind farm(WF)cluster affect the stability and power quality of the interconnected power grid.This ...The power loss minimization and DC voltage stability of the multi-terminal direct current(MTDC)system with large-scale wind farm(WF)cluster affect the stability and power quality of the interconnected power grid.This paper proposes a distributed optimal voltage control(DOVC)strategy,which aims to optimize voltage distribution in MTDC and WF systems,reduce system power losses,and track power dispatch commands.The proposed DOVC strategy employs a bi-level distributed control architecture.At the upper level,the MTDC controller coordinates power flow,DC-side voltage of grid-side voltage source converters(GSVSCs),and WF-side voltage source converters(WFVSCs)for power loss minimization and DC voltage stabilization of the MTDC system.At the lower level,the WF controller coordinates the controlled bus voltage of WFVSC and the active and reactive power of wind turbines(WTs)to maintain WT terminal voltages within feasible range.Then,the WF controller minimizes the power loss of the WF system,while tracking the optimal command from the upper-level control strategy.Considering the computational tasks of multi-objective optimization with large-scale WF cluster,the proposed DOVC strategy is executed in a distributed manner based on the alternating direction method of multipliers(ADMM).An MTDC system with large-scale WF cluster is established in MATLAB to validate the effectiveness of the proposed DOVC strategy.展开更多
Aiming at the shortcomings of a traditional centralized control in an active distribution network(AND),this paper proposes a leader-follower distributed group cooperative control strategy to realize multiple operation...Aiming at the shortcomings of a traditional centralized control in an active distribution network(AND),this paper proposes a leader-follower distributed group cooperative control strategy to realize multiple operation and control tasks for an ADN.The distributed information exchange protocols of the distributed generation(DG)group devoted to node voltage regulation or exchange power control are developed using a DG power utilization ratio as the consensus variable.On these bases,this study further investigates the leader optimal selection method for a DG group to improve the response speed of the distributed control system.Furthermore,a single or multiple leader selection model is established to minimize the constraints of the one-step convergence factor and the number of leaders to improve the response speed of the distributed control system.The simulation results of the IEEE 33 bus standard test system show the effectiveness of the proposed distributed control strategy.In addition,the response speed of a DG control group can be improved effectively when the single or multiple leaders are selected optimally.展开更多
基金supported by the U.S.Office of Naval Research(N00014-21-1-2175)。
文摘This article presents a distributed periodic eventtriggered(PET)optimal control scheme to achieve generation cost minimization and average bus voltage regulation in DC microgrids.In order to accommodate the generation constraints of the distributed generators(DGs),a virtual incremental cost is firstly designed,based on which an optimality condition is derived to facilitate the control design.To meet the discrete-time(DT)nature of modern control systems,the optimal controller is directly developed in the DT domain.Afterward,to reduce the communication requirement among the controllers,a distributed event-triggered mechanism is introduced for the DT optimal controller.The event-triggered condition is detected periodically and therefore naturally avoids the Zeno phenomenon.The closed-loop system stability is proved by the Lyapunov synthesis for switched systems.The generation cost minimization and average bus voltage regulation are obtained at the equilibrium point.Finally,switch-level microgrid simulations validate the performance of the proposed optimal controller.
基金supported by the National Natural Science Foundation of China under Grant Nos.61374004,61773237,61473170Rizhao Science and Technology Innovation Special Plan(2019cxzx2212)。
文摘This paper is focused on a distributed optimal control design for a class of nonlinear timedelay systems with delayed measurements and communication disruptions.The innovation lies in three aspects.The distributed optimal control method which includes an optimal controller and a bounded controller is designed based on Lyapunov function.The availability of data transmitted through the communication channel depends on a feasibility problem.And a sufficient condition to guarantee ultimate boundedness of the system is given based on appropriate assumptions.The significance of this paper is that this distributed optimal control method is applied to time-delay system.Finally,a simulation example is given to verify the effectiveness of the proposed method.
基金supported by the National Key R&D Program of China(No.2022YFF0608700).
文摘The power loss minimization and DC voltage stability of the multi-terminal direct current(MTDC)system with large-scale wind farm(WF)cluster affect the stability and power quality of the interconnected power grid.This paper proposes a distributed optimal voltage control(DOVC)strategy,which aims to optimize voltage distribution in MTDC and WF systems,reduce system power losses,and track power dispatch commands.The proposed DOVC strategy employs a bi-level distributed control architecture.At the upper level,the MTDC controller coordinates power flow,DC-side voltage of grid-side voltage source converters(GSVSCs),and WF-side voltage source converters(WFVSCs)for power loss minimization and DC voltage stabilization of the MTDC system.At the lower level,the WF controller coordinates the controlled bus voltage of WFVSC and the active and reactive power of wind turbines(WTs)to maintain WT terminal voltages within feasible range.Then,the WF controller minimizes the power loss of the WF system,while tracking the optimal command from the upper-level control strategy.Considering the computational tasks of multi-objective optimization with large-scale WF cluster,the proposed DOVC strategy is executed in a distributed manner based on the alternating direction method of multipliers(ADMM).An MTDC system with large-scale WF cluster is established in MATLAB to validate the effectiveness of the proposed DOVC strategy.
文摘Aiming at the shortcomings of a traditional centralized control in an active distribution network(AND),this paper proposes a leader-follower distributed group cooperative control strategy to realize multiple operation and control tasks for an ADN.The distributed information exchange protocols of the distributed generation(DG)group devoted to node voltage regulation or exchange power control are developed using a DG power utilization ratio as the consensus variable.On these bases,this study further investigates the leader optimal selection method for a DG group to improve the response speed of the distributed control system.Furthermore,a single or multiple leader selection model is established to minimize the constraints of the one-step convergence factor and the number of leaders to improve the response speed of the distributed control system.The simulation results of the IEEE 33 bus standard test system show the effectiveness of the proposed distributed control strategy.In addition,the response speed of a DG control group can be improved effectively when the single or multiple leaders are selected optimally.
