A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> This paper presents an approach for combined optimization of coupled power flows of different energy infrastructures such as electricity, gas, and district heating systems. A steady state power flow model is presented that includes conversion and transmission of an arbitrary number of energy carriers. The couplings between the different infrastructures are explicitly taken into account based on the new concept of energy hubs. With this model, combined economic dispatch and optimal power flow problems are stated covering transmission and conversion of energy. A general optimality condition for optimal dispatch of multiple energy carriers is derived, and the approach is compared with the standard method used for electrical power systems. Finally, the developed tools are demonstrated in examples <s> BIB001 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> Presence of energy hubs in the future vision of energy networks creates a great opportunity for system planners and operators to move towards more efficient systems. The role of energy hubs as the intermediate in multi-carrier energy (MCE) systems calls for a generic framework to study the new upcoming technical as well as economical effects on the system performance. In response, this paper attempts to develop a general optimization and modeling framework for coupled power flow studies on different energy infrastructures. This, as a large-scale nonlinear problem, is approached through a robust optimization technique, i.e., multi-agent genetic algorithm (MAGA). The proposed procedure decomposes the multi-carrier optimal power flow (MCOPF) problem into its traditional separate OPF problem in such a way that the major advantages of simultaneous analysis of MCE systems would not be sacrificed. The presented scheme is then applied to an 11-hubs test system and introduces its expected applicability and robustness in the MCE systems analysis. <s> BIB002 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> This paper presents an optimal expansion planning model for an energy hub with multiple energy systems. Energy hub represents a coupling among various energy infrastructures for supplying electricity, natural gas, and heating loads. Combined heat and power (CHP) and natural gas furnaces are considered within the energy hub to convert energy into other forms. The multiple energy system planning problem would optimally determine appropriate investment candidates for generating units, transmission lines, natural gas furnaces, and CHPs that satisfy electricity and heating load forecasts and hub system constraints. The system performances associated with reliability, energy efficiency, and emission matrices is evaluated for the identified planning schedules. Numerical simulations demonstrate the effectiveness of the proposed multiple energy system expansion planning approach based on energy hub. <s> BIB003 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> Domestic households account for a significant portion of energy consumption and carbon emissions in the United Kingdom. Gains in energy and resource efficiency are undermined by the continuing rise in consumption. A multiutility service company (MUSCo) could enable households to make efficiency improvements through energy technologies and demand management, thus reducing overall consumption. We present a system dynamics model for the domestic energy demand and supply system in the United Kingdom, in which MUSCos compete with traditional utility providers. The market transition toward a leasing contracted service is examined and various potential business models explored. © 2015 Wiley Periodicals, Inc. Complexity, 2015 <s> BIB004 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> Integrated energy systems (IESs) are under development for a variety of benefits. District electricity and heating systems (DEHSs) deliver electricity and heat, the most common energy demands, to end-users. This paper studies the interactions in a DEHS considering the time-scale characteristics. Interaction mechanisms of a DEHS are analyzed. A disturbance in one system influences another system through coupling components, depending on the disturbance, operating characteristics, and control strategies. A model of the main components in DEHSs is presented. The time scale characteristics are studied based on a dynamic comparison of the different components. Then the interaction process is divided into four stages; each is a quasi-steady state. A quasi-steady multi-energy flow model is proposed and calculated, with a heating network node type transformation technique developed. A case study with detailed results and discussion of 3 types of disturbance is presented to verify the methods. The results present the interactions between the electricity and the system. It is suggested that attention should be paid both on the fast hydraulic process and slow thermal process for system security and economic operation. <s> BIB005 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> The widespread use of decentralised multi-energy supply solutions such as gas-fired Combined Heat and Power (CHP), heat pumps, gas boilers, and so forth is more and more increasing the linkages between electricity, heat and gas distribution networks. However, there is currently no model able to model the three networks in an integrated manner and with a suitable level of detail for operational purposes. A multi-temporal simulation model, which has been implemented in a relevant MATLAB-Excel VBA tool, is presented in this paper to carry out integrated analysis of electricity, heat and gas distribution networks, with specific applications to multi-vector district energy systems. The network linkages have been modelled through a multi-vector efficiency matrix specifically developed to map the transformation of final demands into network energy flows while taking into account the inter-network locations of the individual supply technologies. The relevant coupled electrical, heat and gas flow equations have been solved simultaneously using a Newton–Raphson approach. A real case study of a district multi-energy system in the Campus of the University of Manchester illustrates the quantitative use of the model in different scenarios for technical, economic and environmental studies. Sankey diagrams of the energy flows across the networks are also presented to give a visual picture of the multi-energy interactions and losses in the district in different scenarios. The model can be flexibly adapted to generic network topologies and multi-energy supply technologies, and can thus be used for practical operational implementations as well as to inform planning of low carbon multi-vector energy systems. <s> BIB006 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> In the smart grid and future energy internet environment, a regional energy service provider (RESP) may be able to integrate multiple energy resources such as generator units, demand response, electrical vehicle charging/swapping stations, and carbon emission trading to participate in the market. By imploring a well-known portfolio optimization theory conditional value-at-risk to tackle electricity price uncertainty, this paper formulates the risk-averse day-ahead operational planning for such a RESP as a mixed-integer quadratically constrained programming (MIQCP), named as RA-RESP. A global optimization method, named as multiple perspective-cuts outer approximation method (MPC-OAM) is proposed to solve this model efficiently. A remarkable stronger and tighter mixed integer linear programing master problem is designed to accelerate the convergence of the proposed method. Comprehensive simulation results show that, compared with existing day-ahead planning models, the RA-RESP is a good compromise between profit-based models and cost-based ones. The proposed MPC-OAM can solve complicated RA-RESP problem efficiently, and compared with state-of-the-art solution techniques, the MPC-OAM outperforms in both computing speed and solution quality, especially for scenario which includes more nonlinear factors. <s> BIB007 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> The extensive installation of gas-fired power plants in many parts of the world has led electric systems to depend heavily on reliable gas supplies. The use of gas-fired generators for peak load and reserve provision causes high intra-day variability in withdrawals from high pressure gas transmission systems. Such variability can lead to gas price fluctuations and supply disruptions that affect electric generator dispatch, electricity prices, and threaten the security of power systems and gas pipelines. These infrastructures function on vastly different spatiotemporal scales, which prevents current practices for separate operations and market clearing from being coordinated. In this paper, we apply new techniques for control of dynamic gas flows on pipeline networks to examine day-ahead scheduling of electric generator dispatch and gas compressor operation for different levels of integration, spanning from separate forecasting and simulation to combined optimal control. We formulate multiple coordination scenarios and develop tractable, physically accurate computational implementations. These scenarios are compared using an integrated model of test networks for power and gas systems with 24 nodes and 24 pipes, respectively, which are coupled through gas-fired generators. The analysis quantifies the economic efficiency and security benefits of gas-electric coordination and dynamic gas system operation. <s> BIB008 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> Under the background of global energy conservation, the energy hub (EH)-based integrated energy system is becoming the transition direction of future energy structure. In this paper, we study the cooperative economic scheduling problem for multiple neighboring integrated energy systems on the basis of EH. Different with the traditional non-cooperative mode where each EH operates individually, these EHs constitute a cooperative community and can share energy among them. Considering the autonomy and self-interest of different EHs, the coordinated management problem is modeled as a bargaining cooperative game, where involved EHs will bargain with each other about the exchanged energy and the associated payments. The bargaining solution can achieve a fair and Pareto-optimal balance among the objective functions of different EHs. A distributed optimization is applied to find the bargaining solution of the cooperative system, to guarantee the autonomous scheduling and information privacy of EHs. Numerical studies demonstrate the effectiveness of the bargaining-based cooperative economic scheduling framework, and also show the improvement of benefits of the community system. <s> BIB009 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> In this paper, a new decomposing strategy is proposed to solve the power flow problem in the large-scale multienergy carrier (MEC) systems, including gas, electrical, and heating subnetworks. This strategy has been equipped with a novel noniterative method named holomorphic embedding (HE) to solve the energy flow of the electrical subnetwork. Moreover, it benefits from the less-computational graph method for solving the energy flows of the heating subnetwork. The HE method unlike initial-guess iterative methods guarantees to find the power flow solution, if there is a solution. In addition, it finds only the operational power flow solution without concern about the convergence of the solution. In the proposed strategy, the decomposing method decouples various energy flows of subnetworks without losing the major benefits of the simultaneous analysis of the subnetworks and losing accuracy. Moreover, the proposed decomposing strategy has more reliability and faster computation time than the Newton–Raphson technique. In order to demonstrate the efficiency and superiority of the proposed decomposing strategy on solving large-scale MEC systems, the strategy is tested on three large-scale case studies. <s> BIB010 </s> A Survey on Optimal Control and Operation of Integrated Energy Systems <s> Modeling of Equipment with Other Coupling. <s> There is increasing interest in multi-energy communities, which could become important sources of demand response flexibility, especially when equipped with storage. Their location on distribution networks mean their exploitation to solve local capacity congestions may be particularly valuable, whilst their ability to partake in energy/reserve markets can improve their business cases. However, maximizing this flexibility potential by providing multiple services that are subject to uncertain calls is a challenging modeling task. To address this, we present a stochastic energy/reserve mixed integer linear program for a community energy system with consideration of local network constraints. By covering all the relevant energy vectors, the multi-energy formulation allows comprehensive modeling of different flexibility options, namely, multi-energy storage, energy vector substitution, end-service curtailment, and power factor manipulation. A key feature of the approach is its robustness against any reserve call, ensuring that occupant thermal comfort cannot be degraded beyond agreed limits in the event of a call. The approach is demonstrated through a case study that illustrates how the different flexibility options can be used to integrate more electric heat pumps into a capacity constrained smart district that is managed as a community energy system, while maximizing its revenues from multiple markets/services. <s> BIB011
Electric refrigerator is a typical electro-cooling coupling device; electric heating boiler is a typical electro-thermal coupling device; gas boiler is a typical gas-thermal coupling device; and adsorption refrigerator is a typical thermal-cold coupling device. When the heating of gas turbine is insu cient, the gas boiler supplements the heating. e mathematical model of a gas boiler is expressed as BIB004 : where gb and gb are the output heat power and consumption of natural gas of gas boiler in t period, respectively; gb is the operating e ciency of gas boiler. e main coupler of the thermal-cooling system is the adsorption refrigerator, the main coupler of the electriccooling system is the electric refrigerator, and the main coupler (9) , , = ,ℎ 2 , gas * 4 , transmission network, and thermal transmission network. e overall optimal dispatch of IES is mainly a problem of optimal hybrid power ow of multienergy. Appropriate interconnection can reduce consumption and reserve capacity of generation, and make full use of power generation equipment, which is a method that can make the energy equipment the most e ective in any region. ere will be various forms of energy exchange between IES BIB011 BIB009 BIB007 BIB010 and the concept of energy hub is constructed. Each energy hub is regarded as a generalized node in the network, and the energy ow on the transmission line is similar to the optimal power ow of the power system, which is called the optimal power ow of multienergy system BIB005 . Figure  4 shows a typical cross-regional IES schematic. On the basis of the optimal hybrid power ow, the problem of IES at the regional and cross-regional levels is to calculate the optimal hybrid power ow of the system, thus revealing the operation mechanism of multiple IES, and providing theoretical guidance for the optimal operation and energy dispatch of IES at regional and cross-regional levels. Moreover, the optimal hybrid power ow calculation generally chooses the system operation economy as the optimization objective, and its constraints are energy ow equation constraints of IES, energy production and consumption constraints, conversion and energy storage equipment constraints, while considering the energy constraints of multienergy coupling equipment of IES BIB006 BIB002 BIB008 BIB001 BIB003 . e basic optimization model is shown as follows: where , the function related to energy input and power ow of energy network; the rst and second constraints are energy ow equation constraints in energy networks and upper and lower limits in networks.