Byeong-Yeon Kim

Consensus-Based Coordination and Control for Building Automation Systems

This brief presents coordination and control for heating energy distribution in building automation systems. Building thermal networks consist of rooms that are interconnected through communication and physical heat transfer networks. Since there exist heat generation constraints and temperature constraints of rooms, it is required to coordinate heat generation at each room and control heat flows among rooms. The temperature of each room is determined by heat generation coordination and heat flow control. In this brief, the heating energy distribution is achieved by consensus-based coordination and control in a distributed manner. Consensus schemes using only local information are employed to the heat generation coordination and the heat flow control. The validity of the proposed approaches is investigated through an illustrative example.

Distributed Coordination and Control for a Freeway Traffic Network Using Consensus Algorithms

This paper presents the coordination and control for a freeway traffic network. Since a mismatch between the freeway capacity and the amount of traffic flow leads to freeway congestion, it is required to achieve the desired traffic density in the freeway traffic network. The traffic density of each cell is determined by the on-ramp flow and the main stream inflow. In addition, each cell has different on-ramp-flow constraints and main-stream-inflow constraints. Thus, it is required to coordinate the on-ramp flow and control the main stream inflow to achieve the desired traffic density for each cell. In this paper, a consensus-based coordination and control for a nonhomogeneous freeway traffic network is developed in a distributed manner. For the on-ramp-flow coordination and the main-stream-inflow control, consensus schemes only using local information are employed. Thus, this paper proposes a distributed on-ramp-flow coordination scheme and a main-stream-inflow control method considering constraints based on distributed consensus algorithms. Through numerical simulations, the effectiveness of the proposed approaches is illustrated.

Stability analysis of spatially interconnected discrete-time systems with random delays and structured uncertainties

Abstract In this paper, robust stability analysis of spatially interconnected systems with random delays as well as structured uncertainties in discrete-time domain is presented. The random delays are represented as a series of Markovian jumping parameters with some transition probability. A sufficient condition to guarantee well-posedness, stochastic stability, and H ∞ performance of the spatially interconnected systems is established. Through numerical simulations, the validity of the proposed approach is illustrated.

Power distribution with consensus

In a smart grid which is a kind of distributed power systems, it is required to maintain supply-demand balance. For supply-demand balance, it is necessary to determine the amount of power needed at each distributed power resource. Also, coordination of power flows among distributed power resources is an important issue. This paper proposes command coordination and power flow control for supply-demand balance in distributed power systems using consensus scheme.

Iterative learning control for spatially interconnected systems

Abstract Iterative learning control (ILC) has been successfully employed for trajectory tracking of uncertain dynamic systems with less system information. This paper attempts to adopt the benefits of ILC to improve the trajectory tracking performance of spatially interconnected systems. By utilizing the ILC update law along the iteration domain repetitively, a perfect reference trajectory tracking can be ensured. It is the key benefit of using ILC that less system model information is used in the design of a trajectory tracking controller for spatially interconnected systems. Through a numerical simulation, the validity of the proposed control scheme is illustrated.

Coordination and control for freeway traffic network

This paper presents coordination and control for achieving given desired traffic density in a freeway traffic network. The traffic density of each cell is determined by on-ramp flow and main stream inflow. Also, each cell has on-ramp flow constraints and main stream inflow constraints. Thus, it is required to coordinate on-ramp flow and control the main stream inflow to achieve the given desired traffic density for each cell. In this paper, the coordination and control is achieved in a distributed manner. Consensus schemes using only local information are employed to the on-ramp flow coordination and the main stream inflow control. Thus, this paper proposes a decentralized on-ramp flow coordination scheme and a main stream inflow control method considering constraints based on distributed consensus algorithms.

Control of inter-agent distances in cyclic polygon formations

This paper considers n-agent cyclic polygon formations of mobile autonomous agents in the plane. The aim of each agent is to maintain a desired distance from its neighbor. Since the formation graph is directed, only one agent is responsible for maintaining each distance. The control law for each agent is designed in distributive manner. Hence, it utilizes only local information. We use gradient-like control and Lyapunov-based stability analysis. Since there exist invariant subsets which include undesirable equilibrium state, the inter-agent distances are not globally stable under the given control law. However, once the initial locations of the agents are not inside the subsets, the agents do not approach them.

Bilateral teleoperation systems using genetic algorithms

This paper presents a synchronization scheme of bilateral teleoperation systems with time delay using genetic algorithms. In general, bilateral teleoperation systems have two main goals: stability and transparency. The system can be destabilized by time delay in the communication channel between the master and the slave. Also, transparency can be degraded by time delay. However, it is not easy to determine control gains to achieve these goals. In this work, we use genetic algorithms to choose optimal control gains for synchronization control law. Consequently, position and force tracking problem in free and contact motion is solved in a synchronized manner. Simulation results are presented to verify the effectiveness of proposed methods.

Distributed Coordination for Optimal Energy Generation and Distribution in Cyber-Physical Energy Networks

This paper proposes three coordination laws for optimal energy generation and distribution in energy network, which is composed of physical flow layer and cyber communication layer. The physical energy flows through the physical layer; but all the energies are coordinated to generate and flow by distributed coordination algorithms on the basis of communication information. First, distributed energy generation and energy distribution laws are proposed in a decoupled manner without considering the interactive characteristics between the energy generation and energy distribution. Second, a joint coordination law to treat the energy generation and energy distribution in a coupled manner taking account of the interactive characteristics is designed. Third, to handle over- or less-energy generation cases, an energy distribution law for networks with batteries is designed. The coordination laws proposed in this paper are fully distributed in the sense that they are decided optimally only using relative information among neighboring nodes. Through numerical simulations, the validity of the proposed distributed coordination laws is illustrated.

Coordination and control for building automation systems

This paper presents coordination and control for heating energy distribution in building automation systems. The temperature of each room is determined by heating energy coordination and heat flow control. In this paper, the coordination and control is achieved in a distributed manner. Consensus schemes using only local information are employed to the heating energy coordination and the heat flow control. Thus, this paper proposes a distributed heating energy coordination scheme and a heat flow control method considering constraints based on distributed consensus algorithms.