Construction of Energy Hub Model and Optimal Scheduling of Energy Internet Lei Meng 1 , Dongsheng Yang 1 , Yunhe Sun 1 , Huaguang zhang 1 1. College of Information Science and Engineering, Northeastern University, Box 134, 110819, LN Shenyang, P.R. China E-mail: yangdongsheng@mail.neu.edu.cn Abstract: This paper studies the construction and optimal scheduling issues of energy internet power flow, considering electrical, natural gas and heating integratedly. Firstly, a new data based modeling method of energy hub is proposed, which is much simpler than mechanism based methods. Then the working pattern of energy internet is proposed in this paper, and based on that, the hybrid energy optimization problems is studied. Finally, by constructing an integrated energy internet which contains the three kinds of energy and other distributed energy devices like CHP unit, compressors and renewable energy generators etc., the reasonability of method put forward in this paper is verified. Key Words: Energy internet, multi-energy, energy hub, optimal scheduling 1 Introduction The development of energy internet is of great signifi- cance to the current energy structure. With energy internet, integrated control, distribution and scheduling of diverse en- ergy can be realized. Energy internet is a kind of integrated energy network which contains energy storage, reginal con- version and transmission and global interconnection of ener- gy. Since the development of energy internet is still on the theoretical study stage, most of its theory and technology is incomplete. The conceptual architecture of energy internet which contains the energy hub and energy router was put forward in [1]. Based on the theory of static energy router that was proposed in [2] and [3], [4] and [5] constructed the dynamic energy hub model, which can describe the complex dynamical behaviors in integrated energy system. Coordination and optimization of multi-energy sources is a critical issue in the development of energy internet. So that the related technologies of integrated energy systems have been widely studied by researchers. The energy integration mainly been realized by the CCHP unit using renewable en- ergy, and behaves as interactions between electricity, natural gas, and heating. In the past, the multi energy optimization control problem was only studied by analysing the mathe- matical model of generation, distribution and transmission of single energy [6], [7]. More recently, several research- es have been addressed on the multi-energy problems [8], [9], which using multiobjective programming method, tak- ing the lowest operating cost, the least energy waste as the optimization targets, while the equality constraints and in- equality constraints of operation and power loss should be met. In particular, on the basis of the construction of energy hub model, the optimal scheduling method of muti-energy in energy internet is proposed in [10]. This paper focuses on the model building of energy hub and the operation and optimal scheduling problems of ener- gy internet. According to the structure and function require- ment of the energy hub, the general energy conversion mod- el is constructed. For the modeling of multi energy fusion This work is supported by National Natural Science Foundation (NNS- F) of China under Grant 61273029, 61433004, and the Fundamental Re- search Funds for the Central Universities under grant N160402003. and scheduling, the equilibrium relationships of electricity, natural gas and heating networks security operation are con- structed, and through the establishment of optimal control strategies, the energy internet can achieve its steadily oper- ation. Finally, a simulation example is given to verify the reasonability of proposed method. 2 The Architecture, Functions and Modeling Method of Energy Hub Energy hub is a key approach for the achievement of ener- gy internet and future energy networks. An energy hub is a unit where multiple energy carriers can be converted, condi- tioned, and stored. It’s an interface between different energy infrastructures and/or loads [3]. Energy hubs consume pow- er like electricity,natural gas, fuels and renewable energy at their input ports, and provide certain required energy such as electricity, heating, cooling and other energy products at their output ports. So that for the different The energy hub can be classified as single energy hub (SISO unit) and multi energy hub (MIMO unit) [2] according to the number of in- put and output power type; from the aspect of load demand, the energy hub can be divided into electricity-heat, natural gas-electricity, natural gas-heat as well as their combination. It would be of great difficulty to build the mathematical model of energy hub if we implement it from the aspect of its structure or working mechanism, thus we can solve this problem by research the conversion efficiency between in- put and output energy sources. The input and output ener- gy sources can be seen as two kinds of variables that have specific coupling relationship, while the coupling factors are their conversion efficiencies which can be obtained from op- erating data of electric boilers, steam turbines, gas-fired boil- ers and other conversion equipments. When the problem of energy optimization and scheduling is concerned, every cou- pling coefficient will be multiplied by a scheduling factor, and by changing these factors, the transfer quantity of differ- ent energy can be controlled. For the SISO energy hub, its structure can be simplified as Fig.1, so that the coupling relationship between output energy L and input energy P can be expressed as: L β = c αβ P α ,where c αβ is the coupling factor between output and input energy which can be defined as the steady state trans-