Researches On The Key Problem Of Operation Optimization For Smart Micro-grid

Smart micro-grid is an important research project,which reflects the development of new energy technologies.And it plays an important role in solving the problem of flexible power supply,improving the utilization efficiency of renewable energy,and addressing the problem of energy shortages and environmental issues.Moreover,the economic operation and energy management of smart micro-grid is an important guarantee to realize the economic,safe and reliable power supply.Meanwhile,the main task is to establish an accurate economic operation optimization model based on the fundamental forecast date of renewable energy,load demand and market price.By selecting appropriate operation policy and optimization algorithms,a solution method is developed to solve the problem.And then,under the condition of safe and reliable operation of smart micro-grid,the minimum cost,efficient use of energy and reducing pollutant gas emissions can be realized.However,the multiple types of micro-sources' characteristics,higher energy penetration rate of renewable energy,energy of bidirectional flow,power exchange between smart micro-grid and external distribution network,which bring big challenges to the economic operation of smart micro-grid.In order to solve the above problems,a smart micro-grid is considered as the research project.The complicated issue of operation optimization is researched under the uncertainty associated to renewable energy and load demand,muti-objective of economic and environment,and strong coupling of the adjacent time sections.Moreover,the theoretical basis of operation optimization under complex operating conditions is established,where system engineering optimization is employed to develop smart micro-grid operation optimization method in this research.The main works and contributions are summarized as follows.1.In this paper,a centralized energy management system for smart micro-grid is considered.Firstly,the steady-state and dynamic models of micro-sources are established.Thereafter,the cost model of micro-sources and the economic operation optimization model of smart micro-grid are proposed.And then,the HSS is used to solve the problem.Finally,the study on case proves the validity of this optimization methodology.2.Aiming at the inherent intermittency and randomness of renewable energy,a methodology based on scenarios and policy aggregation is associated.Sub-problems are derived from the optimization problems considering the uncertainty.Meanwhile,an information structure by scenario bundling is introduced.At the same time,the policies are divided into admissible policies,implementable policies,and contingent policies.And then,iterative adjustments according to available information evolved mechanism are made to the decision policy to adapt to this information structure.At last,the overall results of investigated problem considering uncertainty are obtained by identified trends and essential features on the solutions of the sub-problems.3.Aiming at dynamic adjustment of energy storage system and controllable micro sources because of renewable energy changing rapidly and frequently,dynamic operation optimization problem with complex constraints is proposed.Firstly,Lagrange multipliers and interior point method are incorporated to solve the complex constraints.Thereafter,the dynamic programming is proposed to solve the dynamic operation optimization problem and obtain the optimal solution.4.Aiming at the optimal output of micro-grid changing with electrical price and load demand,and the necessary of reformulating the economic operation problem of smart micro-grid and computing the problem repetitively.Firstly,the GA is used to solve operation optimization of micro-grid.And then,a learning algorithm such as neural network is used to realize online optimization of smart micro-grid.5.Aiming at the muti-objective operation optimization problem of smart micro-grid with minimizing operational cost,pollution gas emissions and cost of depreciation,decomposition based muti-objective evolutionary algorithm is extended.Aiming at the complex constraints of smart micro-grid economic operation optimization problem,the constraint violation(CV)and performance metric such the PBI or Tchebycheff metrics can be used to check the solutions for replacing the members.Aiming at the danger of being trapped in local optimal,differential evolution(DE)and niche guided mating selection strategy are incorporated to improve the optimization process.