The Voltage Control Method Considering The Characteristics Of Microgrid In The Power Comprehensive Reform Area

With the continuous of the power system reform,the two major measures,the sales market and incremental grid distribution,have greatly promoted the development of distributed generation technologies and microgrid technologies.However,there are still many problems,such as the modeling of the characteristics of the microgrids,the influence of the integration of the microgrids on the distribution network and the voltage control method used to eliminate the grid-connected effect of the microgrids.So solving these problems will greatly promote the development of the microgrid-distribution network in the comprehensive rectification zone,which is of great significance for guiding the access of the microgrid and maintaining the safe and stable operation of the distribution network.In this paper,three main types of microgrids in Shanxi Electric Power Comprehensive Rehabilitation Area are established,and their external characteristics models are established respectively.The influence rules on voltage distribution are studied.Then,the voltage control method is proposed to ensure the microgrid-distribution network in safe and stable state.For different types of microgrids,due to the difference of their internal power supply,considering the relationship between the power generation cost of each power supply,the price of feed-in electricity and the price of power grid,maximizing the operating profit inside the micro-grid as the goal to determine the operation strategy of the internal power supply.Through the simulation,the microgrid external characteristic curves of the three microgrids under different seasons and weather conditions are obtained.In the case of grid-connected microgrid,based on the above curves of microgrid external characteristics,the voltage distribution of these factors is studied by changing the type of grid-connected microgrid,the access mode of microgrid and the permeability of microgrid.After understanding the influence of grid-connected microgrid on distribution network voltage distribution,a multi-time-scale voltage-coordinated closed-loop control method is proposed for the scenario of voltage over limited.The switching of OLTC and shunt capacitors have been optimized in day-ahead optimization.The reactive power output of the grid-owned PV has been optimized during the day.And the correction of day-ahead optimization is added.Simulation results show that the control method is effective and reasonable.