Research On Distribution Network Multi-source Coordinated Control Strategy With Distributed Generation Interconnection

With the development of the distributed power generation technology,the distributed distribution has been.Distribution network characteristic has changed from radial network structure and single power scource supply system to bi-directional flow characteristics and multi-source supply system.At the same time,with distribued generation interconnection,the short circuit current,load flow,voltage distribution characteristics of distribution network have changed,which brings a series new challenges to the power system planning,operation and control.This thesis researches the influence of distribued generation interconnection,the grid-connected inverter control strategy and the microgrid integrated energy management system,and the specific research contents include:(1)Analysis the influence of safety for maintenance personnel,safety for the user and the impact on the operation safety of power distribution network with distribued generation interconnection.Considering distribued generation interconnection,the effect of the existing mathematical model for distributed system,operation and management method,distributed generation data acquisition and monitoring system,distributed generation comprehensive performance evaluation and data analysis method are studied.Focus on analysis of operation management,protection,reclosing and load flow management,power distribution network remould suggestions is put forward,in order to adapt to the mass of distributed generation grid connected.(2)Study the principle and structure of virtual synchronous generator,and verify the virtual synchronous generator through simulation example.Because of high power electric vehicle charging having a great influence to the power system safe and stable,a electric vehicle charging strategy based on virtual synchronous generator theory is put forward according to the principle of PWM rectifier four quadrant operation theory,through adding the current inner loop control links,and a simulation case is studied.(3)With the electric vehicle development and a lot of electric vehicle charging,a stochastic optimization of microgrid economy model predictive control strategy is proposed,considering renewable energy power generation stochasticity and thermal power load forecast uncertainty,combined with multi-energy balance and orderly electric vehicle charging control and demand side management,so as to realize the minimum cost and optimization energy managment.Based on model predictive control theory,the time domain rolling optimization method is applied to reduce the affect of forecast uncertainty to the system stability and robustness.Meanwhile,the scene cuts and parallel computing methods are introduced to meet the need of practical application such as solving speed and precision.At last,a simulation of microgrid economy model predictive control strategy is studied.