Simulation and the monte carlo method

Historically, centrally computed algorithms have been the primary means of power system optimization and control. With increasing penetrations of distributed energy resources requiring optimization and control of power systems with many controllable devices, distributed algorithms have been the subject of significant research interest. This paper surveys the literature of distributed algorithms with applications to optimization and control of power systems. In particular, this paper reviews distributed algorithms for offline solution of optimal power flow (OPF) problems as well as online algorithms for real-time solution of OPF, optimal frequency control, optimal voltage control, and optimal wide-area control problems.

https://ieeexplore.ieee.org/ielaam/5165411/8075182/7990560-aam.pdf

A Survey of Distributed Optimization and Control Algorithms for Electric Power Systems

This paper presents a comprehensive review and assessment of the latest research and advancement of electric vehicles (EVs) interaction with smart grid portraying the future electric power system model. The concept goal of the smart grid along with the future deployment of the EVs puts forward various challenges in terms of electric grid infrastructure, communication and control. Following an intensive review on advanced smart metering and communication infrastructures, the strategy for integrating the EVs into the electric grid is presented. Various EV smart charging technologies are also extensively examined with the perspective of their potential, impacts and limitations under the vehicle-to-grid (V2G) phenomenon. Moreover, the high penetration of renewable energy sources (wind and photovoltaic solar) is soaring up into the power system. However, their intermittent power output poses different challenges on the planning, operation and control of the power system networks. On the other hand, the deployment of EVs in the energy market can compensate for the fluctuations of the electric grid. In this context, a literature review on the integration of the renewable energy and the latest feasible solution using EVs with the insight of the promising research gap to be covered up are investigated. Furthermore, the feasibility of the smart V2G system is thoroughly discussed. In this paper, the EVs interactions with the smart grid as the future energy system model are extensively discussed and research gap is revealed for the possible solutions.

Electric vehicles and smart grid interaction: A review on vehicle to grid and renewable energy sources integration

Large amounts of data are increasingly accumulated in the energy sector with the continuous application of sensors, wireless transmission, network communication, and cloud computing technologies. To fulfill the potential of energy big data and obtain insights to achieve smart energy management, we present a comprehensive study of big data driven smart energy management. We first discuss the sources and characteristics of energy big data. Also, a process model of big data driven smart energy management is proposed. Then taking smart grid as the research background, we provide a systematic review of big data analytics for smart energy management. It is discussed from four major aspects, namely power generation side management, microgrid and renewable energy management, asset management and collaborative operation, as well as demand side management (DSM). Afterwards, the industrial development of big data-driven smart energy management is analyzed and discussed. Finally, we point out the challenges of big data-driven smart energy management in IT infrastructure, data collection and governance, data integration and sharing, processing and analysis, security and privacy, and professionals.

Big data driven smart energy management: From big data to big insights

The regional integration of variable wind power could be restricted by a strong coupling of electric power generation dispatch and heat supply of combined heat-and-power (CHP) units. The coupling in cold seasons precludes CHPs from providing the necessary flexibility for managing the wind power dispatch. The lack of flexibility problem can be tackled by exploiting the energy storage capability of a district heating network (DHN) which decouples the strong linkage of electric power and heat supplies. In this paper, a combined heat and power dispatch (CHPD) is formulated to coordinate the operation of electric power system (EPS) and district heating system (DHS). The proposed CHPD model which is solved by an iterative method considers the temperature dynamics of DHN for exploiting energy storage as an option for managing the variability of wind energy. The simulation results are discussed for several test systems to demonstrate the potential benefits of the proposed method in terms of operation economics, wind power utilization, as well as the potential benefits for real systems.

Combined Heat and Power Dispatch Considering Pipeline Energy Storage of District Heating Network

Wind power integration could be restricted by inflexible operation of combined heat and power (CHP) units due to the strong linkage between power generation and heating supply in winter. Utilization of the heat storage capacity of existing district heating network (DHN) is a cost-effective measure to enhance power system operational flexibility to accommodate large amounts of variable wind power. In this paper, transmission-constrained unit commitment (UC) with combined electricity and district heating networks (UC-CEHN) is formulated with a linear DHN model to coordinate short-term operation of electric power and district heating systems. The heat storage capacity of the DHN is modeled by capturing the quasi-dynamics of pipeline temperature. Both deterministic and robust models are developed to incorporate UC with the linear DHN model. Case studies are carried out for two test systems to show the potential benefits of the proposed method in terms of wind power integration and efficient operation.

Transmission-Constrained Unit Commitment Considering Combined Electricity and District Heating Networks

This paper presents a fully distributed reactive power optimization algorithm that can obtain the global optimum solution of nonconvex problems for distribution networks (DNs) without requiring a central coordinator. Second-order conic relaxation is used to achieve exact convexification. A fully distributed second-order cone programming solver (D-SOCP) is formulated corresponding to the given division of areas based on the alternating direction method of multipliers (ADMM) algorithm, which is greatly simplified by exploiting the structure of active DNs. The problem is solved for each area with very little interchange of boundary information between neighboring areas. D-SOCP is extended by using a varying penalty parameter to improve convergence. A proof of its convergence is also given. The effectiveness of the method is demonstrated via numerical simulations using the IEEE 69-bus, 123-bus DNs, and a real 1066-bus distribution system.

A Fully Distributed Reactive Power Optimization and Control Method for Active Distribution Networks

With the recent rapid development of smart grid technology, the distribution grids become more active, and the interaction between transmission and distribution grids becomes more significant. However, in traditional power flow calculations, transmission and distribution grids are separated, which is not suitable for such future smart grids. To achieve a global unified power flow solution to support an integrated analysis for both transmission and distribution grids, we propose a global power flow (GPF) method that considers transmission and distribution grids as a whole in this paper. We construct GPF equations, and develop a master-slave-splitting (MSS) iterative method with convergence guarantee to alleviate boundary mismatches between the transmission and distribution grids. In our method, the GPF problem is split into a transmission power flow and a number of distribution power flow sub-problems, which supports on-line geographically distributed computation. Each sub-problem can be solved using a different power flow algorithm to capture the different features of transmission and distribution grids. An equivalent method is proposed to improve the convergence of the MSS-based GPF calculation for distribution grids that include loops. Numerical simulations validate the effectiveness of the proposed method, in particular when the distribution grid has loops or distributed generators.

Master–Slave-Splitting Based Distributed Global Power Flow Method for Integrated Transmission and Distribution Analysis

Distributed generations (DGs) introduce significant uncertainties to restoration of active distribution networks, in addition to roughly estimated load demands. An adjustable robust restoration optimization model with a two-stage objective is proposed in this paper, involving the uncertain DG outputs and load demands. The first stage generates optimal strategies for recovery of outage power and the second stage seeks the worst-case fluctuation scenarios. The model is formulated as a mixed-integer linear programming problem and solved using the column-and-constraint generation method. The feasibility and reliability of the strategies obtained via this robust optimization model can be guaranteed for all cases in the predefined uncertainty sets with good performance. A technique known as the uncertainty budget is used to adjust the conservativeness of this model, providing a tradeoff between conservativeness and robustness. Numerical tests are carried out on the modified PG&E 69-bus system and a modified 246-bus system to compare the robust optimization model against a deterministic restoration model, which verifies the superiority of this proposed model.

Boming Zhang

Papers

Combined Heat and Power Dispatch Considering Pipeline Energy Storage of District Heating Network

Transmission-Constrained Unit Commitment Considering Combined Electricity and District Heating Networks

A Fully Distributed Reactive Power Optimization and Control Method for Active Distribution Networks

Master–Slave-Splitting Based Distributed Global Power Flow Method for Integrated Transmission and Distribution Analysis

Robust Restoration Method for Active Distribution Networks