Distributed Power Optimization Of Off-Grid Wind-Storage-Hybrid Power Generation System Based On ADMM

With the proposal of the "dual carbon" goal,people pay more and more attention to improving the utilization rate of wind energy and solar energy resources,so the off-grid hybrid power generation system composed of wind and solar storage came into being.From the perspective of reliable operation of the system,electric energy can not be stored on a large scale,and its supply and demand must be balanced in real time,but wind power and photovoltaic power generation have the characteristics of intermittency and uncertainty,which will bring great challenges to the stability and reliability of the power grid,so it is urgent to solve the power optimization problem of off-grid wind-solar storage hybrid power generation system.The power optimization of off-grid wind-solar-storage hybrid power generation system is a multi-subsystem optimization problem,and it is difficult to obtain its convergent solution by traditional distributed optimization methods,and this thesis will improve the Alternating Direction Method of Multipliers-Gaussian penalty function-Gaussian back substitution procedure,ADMM-GPF-GBS,ADMGG)is applied to its optimization problem.Firstly,the mathematical model is established according to the structure of the off-grid wind-solarstorage hybrid power generation system.Secondly,the objective function and constraints of system optimization are designed,and the objective functions and constraints are processed and transformed into the form required for optimization.Finally,ADMM and ADMGG optimization algorithms are used to optimize the power reference values of each subsystem.When ADMM optimization is used,based on the historical data of numerical weather prediction(NWP)and load power,ADMM is used to alternately optimize the power reference values of wind power and photovoltaic power generation in the system,and exchange information through the contact line to obtain the optimal solution of the power reference value of the wind and photovoltaic electronic system.On the basis of ADMM,the correction link is first added to the generalized form of ADMM three operators to form the ADMM-GBS algorithm,and then the Gaussian penalty function is added to form the ADMM-GPF-GBS(ADMGG)algorithm.ADMGG is used to solve the power reference value of wind,photovoltaic and battery subsystems by double-layer distributed iterative,ADMM-GPF prediction layer solves the predicted value of the power reference value of each subsystem,and the GBS correction layer performs the prediction value of Gaussian retrograde correction power reference value,and exchanges information through the contact line to obtain the optimal solution of the power reference value of wind,photovoltaic and battery subsystems.With the help of the simulation platform,the NWP data of Tongxin County of Ningxia and Wujiang District of Jiangsu Province,the state of charge(SOC)and load power of the battery are selected,and the ADMM and ADMGG optimization algorithms are used to simulate and verify the distributed power optimization of the off-grid wind-solar-storage hybrid power generation system,and the optimal power reference values of the optimized wind,photovoltaic and battery are sent to the local controller,and the controller controls the duty cycle of the DC/DC converter in each subsystem.Enables systems to operate optimally.Finally,the simulation results are analyzed,the influence of power value,battery charge and discharge current and discharge depth on the battery life is analyzed,and the convergence characteristics of ADMM and ADMGG and ADMM-GBS under the centralized framework are compared.