Research On Integrated Optimization Of Operation And Planning For Micro Energy Grid

As the epitome of the energy internet,the micro energy grid(MEG)integrates various types of energy supply equipment and energy storage devices,which can achieve multi-energy complementary and multi-network coupling,and provides a new technical means for mitigating the energy crisis.Since the MEG supports a large amount of distributed energy access,the overall planning and operation optimization of the system is the key to more efficient and rational utilization of resources.This dissertation takes the MEG as the research object,builds the MEG system model,and studies the integrated optimization of operation and planning for MEG,according to the structure of the MEG and equipment operation characteristics.Main contents of this dissertation are shown below.Firstly,in order to explore the operation characteristics of various devices and the coupling relationship between various energy sources in the MEG,this dissertation constructs the MEG model with multi-energy flow transmission networks based on the concept of energy bus.Then,system simulation models for renewable energy equipmenrgy storage devices in the MEG are built.Three different types(power,heating,cooling)of transmission networks models are established and analyzed for more accurately reflecting the losses caused by energy transmission networks.The establishment of the MEG system model lays the model basis for subsequent research on operation optimization and planning.Secondly,the MEG day-ahead operation optimization model considering the operational characteristics of multi-energy flow transmission networks is established,with the minimum operation cost of the MEG as the objective function.The optimization model is solved by mixed integer nonlinear programming algorithm.Through the day-ahead operation optimization calculation,it is possible to obtain the operation mode and output of each energy supply device when the operation cost of the MEG is the minimum in the next 24 hours,and the system can be effectively scheduled and managed.The MEG day-ahead operation optimization is the basis for real-time operation optimization and planning.Thirdly,based on model predictive control(MPC),a real-time rolling operation optimization model for the MEG is established with the consideration of volatility of renewable energy equipment output and adjustability of user energy loads.With the goal of tracking the output plan obtained from the day-ahead operation optimizations the operation mode and output of each energy supply device in the MEG are effectively scheduled and optimized in the real-time operation phase.It can meet the real-time supply and demand balance under the premise of balancing the day-ahead operation optimization plan,and realize the real-time economic optimization operation of the MEGFourthly,Combining the operation optimization and planning,an integrated model of operation optimization and planning of the MEG based on improved Kriging model and its solving method are proposed combined with the Latin hypercube sampling method.With the minimum total annual cost as the optimization goal,an integrated model of operation optimization and planning of the MEG is established,and a dynamic Kriging model solution method is proposed.In order to improve the computational efficiency,based on the solution method,an improved Kriging model integrated solution method based on hybrid sampling correction mechanism comprised of minimum surrogate-model point(MSP)criterion,mean square error(MSE)criterion and trust region(TR)criterion is proposed.The effectiveness of the integrated method is verified by case studies.