Research On The Operation Control And Energy Management Strategy Of DC Microgrid

With the large consumption of fossil fuels,renewable energy has received widespread attention and development.Distributed energy is an important form of renewable energy,whose development can effectively solve problems such as environmental pollution and energy shortages.Although the output of distributed power generation is unstable,a DC microgrid consisting of distributed power sources,energy storage units,and loads can ensure the stability and reliability of the microgrid through coordinated control,effectively addressing the problem of unstable output of distributed power generation.Therefore,this article will study the operation control and energy management strategy of the DC microgrid.The main research contents are as follows:(1)Introduce the concept and main structure of the DC microgrid,analyze their principles and models,build photovoltaic systems,energy storage units,and DC/AC converters in MATLAB and conduct simulations.(2)Introduce the principle of photovoltaic Boost circuit,analyze and compare the advantages and disadvantages of three Maximum Power Point Tracking(MPPT)algorithms for photovoltaic systems,and simulate and compare the effects of the three MPPT algorithms.Introduce the Active Disturbance Rejection Control(ADRC)algorithm into the MPPT algorithm to verify its superiority through simulation experiments.(3)Aiming at the problems caused by traditional droop control in energy storage unit,propose an improved droop control strategy by introducing the capacity and state of charge(SOC)of the energy storage unit into the droop coefficient to achieve rapid stability of the microgrid,Compensate for bus voltage deviation through fuzzy control,Introducing the consensus algorithm into the droop control can reduce the impact of communication interruption on droop control.Through MATLAB simulation,it is verified that the improved droop control strategy can realize reasonable allocation of power and stable operation of the system.(4)Design an energy management strategy based on the DC microgrid system,which considers the source-load difference and the state of charge of the energy storage unit.Set different working modes for photovoltaic power,load power,and the state of charge of each energy storage unit,build the DC microgrid model in MATLAB,and switch the modes.The effectiveness of the proposed strategy is verified through simulation.