Microgrids are local power systems that may or may not be connected to the distribution system and are typically controlled by the local operator.Interest in microgrids is rising and it is likely that the number of mi...Microgrids are local power systems that may or may not be connected to the distribution system and are typically controlled by the local operator.Interest in microgrids is rising and it is likely that the number of microgrids connected to distribution networks will increase.Currently,there is no consensus on how microgrids will interact with the distribution system―they have the potential to threaten stability,or to assist.However microgrids,with their emphasis on sophisticated control in order to manage their particular challenges,address many of the problems that will be required to overcome in realizing the smart grid.This paper examines some of the issues involved in connecting microgrids to the distribution networks,and illustrates how microgrids have a key role to play in the development of the smart grid.展开更多
This paper presents a decentralized control strategy for the scheduling of electrical energy activities of a microgrid composed of smart homes connected to a distributor and exchanging renewable energy produced by ind...This paper presents a decentralized control strategy for the scheduling of electrical energy activities of a microgrid composed of smart homes connected to a distributor and exchanging renewable energy produced by individually owned distributed energy resources. The scheduling problem is stated and solved with the aim of reducing the overall energy supply from the grid, by allowing users to exchange the surplus renewable energy and by optimally planning users' controllable loads. We assume that each smart home can both buy/sell energy from/to the grid taking into account time-varying non-linear pricing signals. Simultaneously, smart homes cooperate and may buy/sell locally harvested renewable energy from/to other smart homes. The resulting optimization problem is formulated as a non-convex non-linear programming problem with a coupling of decision variables in the constraints. The proposed solution is based on a novel heuristic iterative decentralized scheme algorithm that suitably extends the Alternating Direction Method of Multipliers to a non-convex and decentralized setting. We discuss the conditions that guarantee the convergence of the presented algorithm. Finally, the application of the proposed technique to a case study under several scenarios shows its effectiveness.展开更多
This paper presents the design, implementation and testing of an embedded system that integrates solar and storage energy resources to smart homes within the smart mierogrid. The proposed system provides the required ...This paper presents the design, implementation and testing of an embedded system that integrates solar and storage energy resources to smart homes within the smart mierogrid. The proposed system provides the required home energy by installing renewable energy and storage devices. It also manages and schedules the power flow during peak and off-peak periods. In addition, a two-way communication protocol is developed to enable the home owners and the utility service provider to improve the energy flow and the consumption efficiency. The system can be an integral part for homes in a smart grid or smart microgrid power networks. A prototype for the proposed system was designed, implemented and tested by using a controlled load bank to simulate a scaled random real house consumption behavior. Three different scenarios were tested and the results and findings are reported. Moreover, data flow security among the home, home owners and utility server is developed to minimize cyber-attaeks.展开更多
Recently, the smart grid has been considered as a next-generation power system to modernize the traditional grid to improve its security, connectivity, efficiency and sustainability.Unfortunately, the smart grid is su...Recently, the smart grid has been considered as a next-generation power system to modernize the traditional grid to improve its security, connectivity, efficiency and sustainability.Unfortunately, the smart grid is susceptible to malicious cyber attacks, which can create serious technical, economical, social and control problems in power network operations. In contrast to the traditional cyber attack minimization techniques, this paper proposes a recursive systematic convolutional(RSC) code and Kalman filter(KF) based method in the context of smart grids.Specifically, the proposed RSC code is used to add redundancy in the microgrid states, and the log maximum a-posterior is used to recover the state information, which is affected by random noises and cyber attacks. Once the estimated states are obtained by KF algorithm, a semidefinite programming based optimal feedback controller is proposed to regulate the system states, so that the power system can operate properly. Test results show that the proposed approach can accurately mitigate the cyber attacks and properly estimate and control the system states.展开更多
At present, the structure of power systems is greatly changing due to the penetration of decentralized generations. Although they encompass a high flexibility potential, their large-scale penetration interferes with t...At present, the structure of power systems is greatly changing due to the penetration of decentralized generations. Although they encompass a high flexibility potential, their large-scale penetration interferes with the power system operation at all voltage levels. To get rid of this flaw and exploit their flexibility, different concepts like Virtual Power Plants, Microgrids and Cellular Approach have been introduced but still no solution is in sight. Under these conditions, it seems quite intriguing to find out whether these concepts are likely to offer a complete solution or not. This paper presents ten criteria to assess the complete Smart Grid solution and introduces a comprehensive evaluation system based on cloud-charts. The paper looks into the already existing solutions, which are respectively based on Virtual Power Plants, Microgrids and Cellular Approach concepts. The investigations have shown that none of these solutions meets all criteria necessary for a complete Smart Grid solution. Even a combination of different criteria fails to yield the desired results.展开更多
This research addresses the planning and scheduling problem in and among the smart homes in a community microgrid. We develop a bi-linear algorithm, named ECO-Trade to generate the near-optimal schedules of the househ...This research addresses the planning and scheduling problem in and among the smart homes in a community microgrid. We develop a bi-linear algorithm, named ECO-Trade to generate the near-optimal schedules of the households’ loads, storage and energy sources. The algorithm also facilitates Peer-to-Peer (P2P) energy trading among the smart homes in a community microgrid. However, P2P trading potentially results in an unfair cost distribution among the participating households. To the best of our knowledge, the ECO-Trade algorithm is the first near-optimal cost optimization algorithm which considers the unfair cost distribution problem for a Demand Side Management (DSM) system coordinated with P2P energy trading. It also solves the time complexity problem of our previously proposed optimal model. Our results show that the solution time of the ECO-Trade algorithm is mostly less than a minute. It also shows that 97% of the solutions generated by the ECO-Trade algorithm are optimal solutions. Furthermore, we analyze the solutions and identify that the algorithm sometimes gets trapped at a local minimum because it alternately sets the microgrid price and quantity as constants. Finally, we describe the reasons of the cost increase by a local minimum and analyze its impact on cost optimization.展开更多
基金supported by the Australian Department of Environment,Water, Heritage and the Arts under Grant No. RDG 08-29
文摘Microgrids are local power systems that may or may not be connected to the distribution system and are typically controlled by the local operator.Interest in microgrids is rising and it is likely that the number of microgrids connected to distribution networks will increase.Currently,there is no consensus on how microgrids will interact with the distribution system―they have the potential to threaten stability,or to assist.However microgrids,with their emphasis on sophisticated control in order to manage their particular challenges,address many of the problems that will be required to overcome in realizing the smart grid.This paper examines some of the issues involved in connecting microgrids to the distribution networks,and illustrates how microgrids have a key role to play in the development of the smart grid.
基金supported by European Regional Development Fund in the "Apulian Technology Clusters SMARTPUGLIA 2020"Program
文摘This paper presents a decentralized control strategy for the scheduling of electrical energy activities of a microgrid composed of smart homes connected to a distributor and exchanging renewable energy produced by individually owned distributed energy resources. The scheduling problem is stated and solved with the aim of reducing the overall energy supply from the grid, by allowing users to exchange the surplus renewable energy and by optimally planning users' controllable loads. We assume that each smart home can both buy/sell energy from/to the grid taking into account time-varying non-linear pricing signals. Simultaneously, smart homes cooperate and may buy/sell locally harvested renewable energy from/to other smart homes. The resulting optimization problem is formulated as a non-convex non-linear programming problem with a coupling of decision variables in the constraints. The proposed solution is based on a novel heuristic iterative decentralized scheme algorithm that suitably extends the Alternating Direction Method of Multipliers to a non-convex and decentralized setting. We discuss the conditions that guarantee the convergence of the presented algorithm. Finally, the application of the proposed technique to a case study under several scenarios shows its effectiveness.
文摘This paper presents the design, implementation and testing of an embedded system that integrates solar and storage energy resources to smart homes within the smart mierogrid. The proposed system provides the required home energy by installing renewable energy and storage devices. It also manages and schedules the power flow during peak and off-peak periods. In addition, a two-way communication protocol is developed to enable the home owners and the utility service provider to improve the energy flow and the consumption efficiency. The system can be an integral part for homes in a smart grid or smart microgrid power networks. A prototype for the proposed system was designed, implemented and tested by using a controlled load bank to simulate a scaled random real house consumption behavior. Three different scenarios were tested and the results and findings are reported. Moreover, data flow security among the home, home owners and utility server is developed to minimize cyber-attaeks.
文摘Recently, the smart grid has been considered as a next-generation power system to modernize the traditional grid to improve its security, connectivity, efficiency and sustainability.Unfortunately, the smart grid is susceptible to malicious cyber attacks, which can create serious technical, economical, social and control problems in power network operations. In contrast to the traditional cyber attack minimization techniques, this paper proposes a recursive systematic convolutional(RSC) code and Kalman filter(KF) based method in the context of smart grids.Specifically, the proposed RSC code is used to add redundancy in the microgrid states, and the log maximum a-posterior is used to recover the state information, which is affected by random noises and cyber attacks. Once the estimated states are obtained by KF algorithm, a semidefinite programming based optimal feedback controller is proposed to regulate the system states, so that the power system can operate properly. Test results show that the proposed approach can accurately mitigate the cyber attacks and properly estimate and control the system states.
文摘At present, the structure of power systems is greatly changing due to the penetration of decentralized generations. Although they encompass a high flexibility potential, their large-scale penetration interferes with the power system operation at all voltage levels. To get rid of this flaw and exploit their flexibility, different concepts like Virtual Power Plants, Microgrids and Cellular Approach have been introduced but still no solution is in sight. Under these conditions, it seems quite intriguing to find out whether these concepts are likely to offer a complete solution or not. This paper presents ten criteria to assess the complete Smart Grid solution and introduces a comprehensive evaluation system based on cloud-charts. The paper looks into the already existing solutions, which are respectively based on Virtual Power Plants, Microgrids and Cellular Approach concepts. The investigations have shown that none of these solutions meets all criteria necessary for a complete Smart Grid solution. Even a combination of different criteria fails to yield the desired results.
文摘This research addresses the planning and scheduling problem in and among the smart homes in a community microgrid. We develop a bi-linear algorithm, named ECO-Trade to generate the near-optimal schedules of the households’ loads, storage and energy sources. The algorithm also facilitates Peer-to-Peer (P2P) energy trading among the smart homes in a community microgrid. However, P2P trading potentially results in an unfair cost distribution among the participating households. To the best of our knowledge, the ECO-Trade algorithm is the first near-optimal cost optimization algorithm which considers the unfair cost distribution problem for a Demand Side Management (DSM) system coordinated with P2P energy trading. It also solves the time complexity problem of our previously proposed optimal model. Our results show that the solution time of the ECO-Trade algorithm is mostly less than a minute. It also shows that 97% of the solutions generated by the ECO-Trade algorithm are optimal solutions. Furthermore, we analyze the solutions and identify that the algorithm sometimes gets trapped at a local minimum because it alternately sets the microgrid price and quantity as constants. Finally, we describe the reasons of the cost increase by a local minimum and analyze its impact on cost optimization.
