研究発表

Abstract: This paper deals with a decentralized control of smart grid by using overlapping information for load frequency of power networks introducing distributed power generations. The control objective is to minimize the cost function of load frequency control problem. We expand the state space of the system of power networks and propose a decentralized state feedback control of subsystems for the expanded system. Then we contract the decentralized feedback law to match the original system. Finally, we show the effectiveness of the load frequency control by using the proposed decentralized control method through the simulation result of decentralized large scale power network systems.

This paper describes load leveling control by Real-Time Dynamical pricing based on optimization method. First, we propose a profit maximization problem of supply and demand, satisfying the supply constraint and the balancebetween supply and demand. Then we rewrite them to dual problem which minimizes electricity price. We madealgorithm to solve the dual problem by Steepest Descent Method and proof its convergence. Finally some numerical simulations show the effectiveness of the proposed load leveling control.

本講演では，再生可能エネルギーを含む分散型エネルギーネットワークの分散制御問題に関して，分散型制御方策と予測型制御方策を紹介する．具体的には多くのサブシステムを持つ階層型の大規模システムに対する分散制御問題に対して，情報結合構造を共分散拘束として表現するアプローチや，反復勾配法などの最適化手法，モデル予測制御について議論する．更には電力需要のピーク電力を抑えるための方策として，動的かつ柔軟に電力価格を変更するリアルタイムプライシングに対するアプローチの動向についても解説する．

This paper deals with cooperative conveyance control by vehicle swarms with dynamic network topology. First, we introduce a dynamic network topology that depends on relative distance between the vehicles. Secondly, we propose a novel conveyance strategy based on consensus seeking with dynamic network topology. The proposed strategy needs at least one vehicle which can acquire the information of the target-object and network topology among vehicles is time-varying but always connected. Furthermore the strategy is composed of Surround and. Transport mode. To analyze the convergence of conveyance with dynamic network topology, algebraic graph theory and matrix theory are utilized. Finally, numerical simulation results demonstrate the effectiveness of the proposed method. © 2011 SICE.

This paper focuses on a new Force-Reflection (FR) algorithm based on input-to-state stability (ISS) small gain theorem in cooperative work of Single Master-Multiple Slave (SMMS) teleoperation system with time varying communication delay. In this work, we propose a new position tracking control for object grasping and a new FR algorithm based on a PD control to transfer the positions, velocities and force information between both sides of teleoperation. The goals of these methods are to achieve the secure grasping by multiple slave robots and improve the tracking performance of the cooperation SMMS teleoperation system. To analyze stability of the system, the ISS small gain approach is used to show the overall force-reflecting teleoperation to be input-to-state stable. Several experimental results show the effectiveness of our proposed method. © 2011 IEEE.

A theoretical study about H ∞Filter based SLAM is proposed to propose a sufficient condition for estimation purposes. Two different cases of initial state covariance are given and analyzed to obtain a best solution for SLAM problem with consideration of process and measurement noises statistical behavior. If the proposed conditions are not satisfied during estimation, then the estimation will exhibit unbounded uncertainties and consequently result in erroneous inference. Simulation results demonstrates the performance as what this paper suggested on the theoretical analysis. These results consistently supports and guarantees our previous findings. © 2011 IFAC.

This paper deals with a predictive control and estimation problem with information structured constraints in a constrained finite-time optimal control framework. A large-scale system with information structures is defined as a system in which each subsystem collects spatio-temporally different information, and in general it is necessary to collect and process information in a distributed fashion. We propose a novel predictive control scheme and an estimation law with local information that each distributed subsystem obtains. The effectiveness of the proposed control and estimation law is evaluated through numerical simulations of a simplified micro grid. © 2011 ICROS.

This paper analyzes the performance of H∞ Filter(HF) based SLAM(Simultaneous Localization and Mapping) by applying the Covariance Inflation method. We show that via Covariance Inflation, the updated state error covariance matrix is restrictively depends on the number of decorrelated landmarks such as if smaller number of landmarks are being decorrelated from other landmarks, then the decorrelated landmarks has smaller covariance than the correlated landmarks. Even more, HF with Covariance Inflation shows better confidence regarding its estimation in comparison with EKF with Covariance Inflation if the initial state covariance and measurement noise are big. The results are evaluated through several simulation analysis and consistently supports our claims. © 2011 IEEE.

This paper discusses a distributed control for load frequency of electrical power networks based on iterative gradient methods. The control objective is to minimize the quadratic cost function of load frequency control problem, and we apply the distributed control methodology by using iterative gradient methods to complicated large scale electrical power networks. Iterative gradient methods have good flexibility and they are effective for complicated and time-varying distributed power networks. Several numerical simulation results of distributed power network systems including distributed generations, batteries, and renewable energies in order to show the effectiveness of the load frequency control compared with conventional decentralized control and centralized control.

This paper focuses on a new Force-Reflection (FR) algorithm based on input-to-state stability (ISS) small gain theorem in cooperative work of Single Master-Multiple Slave (SMMS) teleoperation system with time varying communication delay. In this work, we propose a new position tracking control for object grasping and a new FR algorithm based on a PD control to transfer the positions, velocities and force information between both sides of teleoperation. The goals of these methods are to achieve the secure grasping by multiple slave robots and improve the tracking performance of the cooperation SMMS teleoperation system. To analyze stability of the system, the ISS small gain approach is used to show the overall force-reflecting teleoperation to be input-to-state stable. Several experimental results show the effectiveness of our proposed method.

This paper discusses the synchronization problem and it’s solutions for large scale power network systems. We analyze dynamical properties of power networks and derive the synchronization condition of electrical generators. First, we employ a termed Kron reduction method to derive swing equation, which describes states of generators. Second, the derived equation is reduced into Non-uniform Kuramoto model, and then, a synchronization condition is derived by using the reduced model. Finally, we have succeed in relaxing the synchronization condition by controlling power units. Effectiveness of the proposed condition is shown via numerical control simulations.

A theoretical study about HFilter based SLAM is proposed to propose a sufficient condition for estimation purposes. Two different cases of initial state covariance are given and analyzed to obtain a best solution for SLAM problem with consideration of process and measurement noises statistical behavior. If the proposed conditions are not satisfied during estimation, then the estimation will exhibit unbounded uncertainties and consequently result in erroneous inference. Simulation results demonstrates the performance as what this paper suggested on the theoretical analysis. These results consistently supports and guarantees our previous findings.

This paper deals with a predictive control and estimation problem with information structured constraints in a constrained finite-time optimal control framework. A large-scale system with information structures is defined as a system in which each subsystem collects spatio-temporally different information, and in general it is necessary to collect and process information in a distributed fashion. We propose a novel predictive control scheme and an estimation law with local information that each distributed subsystem obtains. The effectiveness of the proposed control and estimation law is evaluated through numerical simulations of a simplified micro grid.

This paper considers the transportation support system using multi-vehicle's formation. The objective of our research is to carry the load using four vehicles keeping the formation within formation exchange among vehicles. The control law based on a Lyapunov function is proposed based on the virtual structure and the graph Laplacian. In the simulation and experiment, it is shown that four vehicles can reach the reference position by using　four wheeled mobile vehicles.

This paper deals with an estimate algorithm which considers optimal control input for dynamic target navigation by using wireless sensor networks and distributed Kalman filter. We propose a novel sensor scheduling algorithm based on a neighbor discovery algorithm for discrete-time linear time-invariant systems. Then we propose an estimate algorithm by sharing predicted estimate values and analyze characteristic of this algorithm. Finally, experimental results show effectiveness of the proposed method in sensor networked feedback systems.