Simulation Research On Energy Management Strategy Of AC/DC Hybrid Micro-grid

AC/DC hybrid micro-grid has high reliability,economical and control flexibility,etc.Energy management has always been the research hotspot in the field of micro-grid.This dissertation takes deep and careful researches into energy management of hybrid AC/DC micro-grid.The main work as followings:(1)Coordinate control frameworks and the corresponding control strategies for micro-grid system in grid operation are thoroughly researched.Coordinate and integrate constant power control and DC bus zero-error tracking control so that the control strategies could ensure the micro-grid system supply specified active and reactive power to the grid and at the same time to maintain stable operation of system.On the basis of the coordinated control strategy,a coordinated control strategy of grid-connected power for the micro-grid system with dump load and energy storage is proposed.It ensures the micro-grid system provide specified active power /reactive power to grid,at the same time avoid damage to the energy storage due it's overlarge charging and discharging power.(2)Based on the parallel operation mode,coordinated control strategy of load demand response and storage unit is studied.Aim at the parallel operation mode of hybrid AC/DC micro-grid,this paper establishes coordinated control strategy of storage unit and controlled load in switch array and realizes the optimizing match of the micro source and load.(3)The paper analyzes smooth switch control strategy of system operation mode.Aimed at simplified constant power control and constant voltage and frequency control,switch control algorithm is set up.The control algorithm can reduce transient impulse caused by switch effectively and realize operation mode smooth switch through phase locking,phase synchronization and outer compensation control strategy before switch of operating mode.