PV Micro-grid Energy Storage System Control And Energy Management Technology Research

As the global renewable energy ratio gradually increased,especially the governments preferential policy support for solar energy development,the importance of solar energy in primary energy is more and more prominent.Solar energy have some characteristics like clean,easy to install,feasibility in wide area,make solar energy get the welcome of power station investors,particularly it is suitable for a distributed installation,which make the residents build their own PV power station on their roof or idle land.But the distributed generation power is randomness,the inertia of the system and system capacity is small,especially the solar energy only can generate electricity during the day,it take many troubles to the power plant operator and grid operator,The Micro-grid energy storage system is consist of solar energy system and storage battery system,it propose a new direction for reducing the disadvantage of distributed generation.The battery is used as backup energy power station.In the daytime,the local load can't consume all the output power of PV array,so the excess solar energy will be stored in the battery to reduce the impact on the common grid system under high light intensity in daytime;the system can transfer the battery's chemical energy into AC electricity to local load at night through the DC/DC converter and DC/AC inverter,which can reduce the purchase demand of the public grid power.It also can realize the peak load shifting,and smooth the ripple of the power demand.This paper introduce the required technology of PV energy storage system.It is to describe the types and basic principle of solar modules before simulate the I-V,P-V output characteristics curve of solar module and array in Matlab/simulink tool,and the analysis of MPPT.it also introduce the general inverter and DC/DC circuit topology's operating and control method,mathematic mode of three phase on-grid system,and list the PQ,V/F,Droop control of distributed generation.the paper propose the on-grid,off-grid,battery charging,battery discharging modes,and the modes need to be operated according to system requirement or economic benefit.We build a real 6KVA three phase on/off grid storage hybrid micro grid system at the end,it can verify the different converter's operating performance,and test the different operating modes of the system.it can check that the real system in lab can fulfill the design requirement.