Research On Feasibility Study Of Grid Black-start Based On Photovoltaic And Energy Storage System

Nowadays,the frequent occurrence of large blackout accidents in the world have drawn increasingly concerned about the safe and stable operation of the power grid.As the fist step of power restoration after blackout,black-start has always been an important issue in the field of power system research.For areas with rich solar energy resources,photovoltaics have the conditions as a power source of black-start because of it high energy density and long duration output characteristics.The configuration of energy storage constitutes a light storage combined power system for the black start of the grid with high feasibility.Photovoltaic and energy storage system is highly feasible for grid black-start.Utilizing a new type of power source supply for emergency response to grid accidents,not only has the black-start capability of the regional grid been greatly improved,but also the speed of recovery of the grid has been accelerated,and it has also broadened the application prospect of photovoltaic power generation at the same time.This paper first studies the general black-start process based on photovoltaic and energy storage system,and gives the structure configuration of the photovoltaic and energy storage system for black-start.Starting from the load demand of the black-start,taking into account the limitation of the start-up time on the photovoltaic output,based on the analysis of different time scales,the capacity configuration of the power source is determined.Secondly,the issue of coordinating control power of photovoltaic and energy storage system in black-start is studied.Taking into account PV output fluctuations and the frequent changes in auxiliary load during the black-start process,considring the constraints of energy storage,an energy management strategy of black-start is proposed.And then,aiming at a local grid with a high percentage of photovoltaic power,black-start simulation is performed based on MATLAB/Simulink,which verifies the proposed energy management strategy and the capacity configuration is rational.Thirdly,based on the construction of the regional grid and the configuration of the photovoltaic and energy storage capacity,as well as considering the limitation of execution time,a black-start program is designed to guide the on-site recovery after a grid blackout by determining power source,plant and path of black-start.Finally,based on PSCAD/EMTDC,the black-start simulation model of the optical storage system is built,and the energy storage and photovoltaic control systems were designed respectively.The simulation result of the self-starting process of photovoltaic and energy storage system and system combined with load operation has verified the feasibility of the black-start based on photovoltaic and energy storage system.