Study On Control And Energy Management Strategy Of Dual-Mode Optical Storage Complementary Power Generation System

With the increasing depletion of traditional fossil fuels and the increasingly severe environmental problems,clean energy,represented by solar energy,has received widespread attention,and countries around the world have vigorously developed photovoltaic power generation.However,photovoltaic power generation is greatly affected by environmental factors,the output power has a strong intermittent and fluctuating,to the promotion of photovoltaic power generation has brought adverse effects.The addition of energy storage module can make the photovoltaic power generation system have stronger initiative and controllability,not only can be better integrated into the power grid,but also can effectively achieve the demand side management,to meet the demand for load electricity diversification.In this paper,a kind of optical storage and off-grid all-in-one is designed,which can not only run on the grid,but also run off the network,and a series of research work is carried out,as follows:Firstly,the topological structure of the optical storage and off-grid system is established.The system is mainly composed of photovoltaic module power generation unit,battery energy storage unit,bidirectional DC/AC Converter,local load and so on,the topology structure adopts common DC bus type.The power converter of energy storage unit adopts isolated bidirectional DC/DC converter,which can not only realize electrical isolation,but also easy to realize soft switch,which has high reliability and safety,and can be applied to special power supply occasions such as train socket,compared with traditional non-isolated buck-boost bidirectional DC/DC converter.Secondly,the control strategy design of photovoltaic module power generation unit,battery energy storage unit and bi-directional DC/AC converter is completed.Bidirectional DC/AC converter grid inverter mode,in view of the traditional PI control and PR grid inverter for grid disturbance signal of the weak inhibition problem,put forward a control strategy based on quasi PR single-phase grid inverter control scheme,and in many ways with traditional PI controller and PR controller is compared,proved based on the superiority of quasi PR controller control.Thirdly,the energy management strategy of the system is proposed.This strategy is optical storage and off-grid system stable and safe operation of the core,through the strategy analysis of the optical storage and off-grid systems work in "off-grid run,photovoltaic panels of independent power generation" the boundary of the four patterns such as qualification,discusses the conversion conditions of each mode between grid and off-grid state is given switching control strategy.Finally,on the basis of theory and simulation,the design and development of the optical storage and off-grid integrated machine with rated power of 5kW are completed by ourselves.Taking DSP28069 as the control core,an experiment platform of optical storage and off-grid system was built,and the advantages of quasi-pr control in singlephase non-isolated grid-connected inverter control and the correctness and effectiveness of energy management strategy were verified by experiments.