Research On Load-source Coordinated Optimization Strategy Of Energy Internet Based On Energy Hub

With the gradual depletion of fossil fuels,the contradiction between energy crisis and environmental issues gets more acute,and the installed capacity of wind power,solar and other clean energy sources continues to increase,traditional energy systems urgently need a set of real-time information delivery and control systems to ensure reliable,stable and efficient operation of energy networks under conditions of diversified and high load requirements.For this purpose,the industry has proposed the concept of Energy Internet that deeply integrates the energy system and the Internet.In the framework of Energy Internet,the multi-energy system consisting of electricity,heat and gas is coordinated and optimized in the production,transmission and consumption to realize the advantage complementation and ensure real-time balance of energy supply and consumption.The load-source coordinated optimization strategy of Energy Internet further reduces the gap of day before dispatching plan and the actual needs of energy load gets.In the framework of Energy Internet,energy hub is the conversion center of various forms of energy and plays an important role in analyzing the interaction of load-source between multi-energy systems.Energy hub can break the barrier existing in energy production,transmission,storage and consumption,and promote efficient,safe and diversified patterns of energy production and consumption.This thesis takes the renewable energy accommodation and the coordination of multi-energy systems as the breakthrough point.Based on energy hub and its network model,the load-source coordinated optimization strategy of Energy Internet is studied systematically.The main content and innovation achievement are summarized as follows:(1)In the energy consumption side,the uncertain load curves of cold,heat and power increase the difficulty in load-source coordination.In this connection,a scenario method is adopted to describe the randomness and volatility of multiple energy loads,and the Latin hypercube sampling is introduced to generate the original scenario by sampling the empirical distribution of random variables.To reduce the computational burden,a method of scenario reduction based on Euclidean distance is proposed.The method improves the efficiency of scenario reduction and the load characteristics of multi-energy systems can be described quickly and accurately.(2)For in-depth analysis of the load-source coordinated optimization strategy of Energy Internet,a load-source coordinated optimization method of independent energy hub is proposed considering the energy production and consumption process in residential users.Considering the relevant constraints,the third-order efficiency model of the micro-gas turbine,the high-precision model of the fuel cell,the model of battery and main power grid are established.The neighborhood re-dispatch particle swarm optimization algorithm is used to solve the nonlinear multi-objective optimization problem with the objects of minimizing the total cost and total emission.The balance of load-source can be achieved by coordinating the day before dispatching plan.Finally,the simulation result shows the proposed method can effectively reduce the total cost and emission and provides a novel way for the economic and environmental operation of energy hub.(3)To further tap the potential of multi-energy complementary,a load-source coordinated optimization method of multi-energy hubs is proposed considering the rational use of surplus energy between industries and residences.Considering the relevant constraints,the residential energy hub model and industrial energy hub model are established.The formulated objective of residential energy hub is to minimize the total cost of purchasing electricity,natural gas and thermal by scheduling the operation of combined cooling heating and power(CCHP)units,and the formulated objective of industrial energy hub is to maximum the net revenue of selling steel products including waste heat throughout the whole time horizon.At the same time,a multi-objective weighted optimization algorithm is proposed,and the global optimal solution satisfying the Kuhn-Tucker condition is given.Finally,the simulation result shows the proposed method can significantly reduce the total cost of residential energy hub and improve the total profit of industrial energy hub,and provides a novel technical approach for the load-source coordinated optimization of multi-energy hub.