Economic And Environmental Optimization Of Integrated Energy Systemand Run-off Algorithm Solution

Integrated Energy System(IES)is a system which can use different kinds of energy sources to implement operations including producing,supplying and using.It can complete energy conversion process by using solar power,wind energy and natural gas and use energy by storing,supplying and consuming electric power and heat energy.This system is a new important research direction to increase the efficiency of energy utilization,reduce pollutant emission and exploit renewal energy resources.This paper analyzes the framework of IES and the connotation of energy conversion in energy production,flow and allocation on the basis of the current research situation of IES at home and abroad.And it explains that energy production is the integration of traditional energy,wind energy,solar power,natural gas and other energy;energy flowing is the integration of electric network,heat network and cold supply system;energy allocation is the integration of electrical load,heating load and cooling load.In order to realize the economic and environmental-friendly operation of IES,an optimal dispatching model is made whose objective is the sum of fuel cost,environmental cost and electricity purchasing cost.The cost function of combined heat and power generation,generate electricity only and heat production only is included in fuel cost.Environmental cost contains the cost of emitting carbon dioxide and the emission load of other gas like sulfur dioxide is measured through equivalent weight.Electricity purchasing cost contains wind power generation purchasing and solar power generation purchasing.New energy power generation output such as wind power and solar power is seen as the random variable and take into account its probability distribution,economic and environmental-friendly operation of IES optimal dispatching model is transferred into a stochastic optimal scheduling model.The stochastic problem is managed by Superquantile Method.The simulation result shoes that the higher confidence level,the more scheduling cost,the better environmental protection property.The scheduling result is related to the decision-maker's perspective of profit pursuit and risk aversion.In order to reduce the impact to the system produced by the decision-maker,it is necessary to take a more controlled operation plan and optimization method.We can use frequency controller or grid-connected power controller to transfer the electric power which is obtained from new energy to power supply system and heating supply system respectively so that the grid-connected power can be controlled,adjustable and definable and the electric power real-time balance and the heating power stage balance equation can be described.A new integrated energy system economic and environmental-friendly optimal dispatching model can be built to stabilize randomness of new energy.Simulation results show this method and optimal dispatching model can increase new energy resource utilization rate,reduce the waste of wind and light and make the system become more economical and environmental-friendly.In order to deal with the difficulty when use current algorithm to solve non-linear,non-convex and discontinuous optimal problem,we try a new intelligence algorithm – run-off algorithm.This algorithm's basis unit is each run-off.Each run-off moves in the area which decides by extended position,width of basin and altitude.And modify the width of basin according to the run-off flow direction to update the position of run-off.Simulation results show this algorithm is easy to realize,need fewer iterative times and its convergence rate is higher.Compared with particle swarm optimization and genetic algorithm,it is easier to get a best result.Run-off algorithm and particle swarm optimization have similar optimizing nature,however run-off algorithm has height parameter in addition which can improve the calculation precision.The run-off algorithm is applied to stabilize randomness of new energy in the integrated energy system economic and environmental-friendly optimal dispatching model.Simulation results show wind energy and solar power can be connected to cogeneration system in the form of power supply and heat supply and it can stabilize the randomness of new energy power generation and realize the electric power real-time balance and the heating power stage balance.It reduces the impact of wind energy generation predicted deviations on the system.Integrated Energy System can coordinate the operation of wind energy and solar power generation and reduce the emission of pollution gas.It makes the most of various energy resources and has high effective use of resources.