Study On Regulation And Control Technology Of Distributed PV-storage Microgrid System

Distributed generation (DG) has a series of advantages such as distributingpower locally, saving power transmission and transformation investment andoperation costs, reducing line loss of centralized power transmission, effectivesupplement and support to large power grid; and in many forms of distributed powersupply, distributed photovoltaic generation(DPVG) gets the attention of the countriesgrid agencies with its advantage, such as more flexible, smaller initial investment.DPVG being access to the grid in the form of micro-grid is the most effective way toplay its performance, and combining with DPVG energy-storage(ES) technologycould play the role of stabilizing fluctuations, enhancing energy efficiency and supplyreliability. So distributed PV-Storage microgrid consisting of DPVG, ES, and load notonly can overcome the stochastic volatility of DPVG output,but also improve powersupply system reliability and energy efficiency levels.To optimize energy management in the microgrid, studies on dispatch strategieswith microgrid as the research subject have become hot spot. Acooding to optimalobjects, dispatch strategies are classified as two kinds: fixed strategy and economicdispatch strategy. The object of the fixed strategy is for enhancing energy efficiencyof DG in the microgrid, and the economic dispatch strategy for enhancing economicefficiency of micro-grid operation on the basis of meeting the load demand.No matterwhich strategy adopted, once dispatch strategy is determined, it is significant thatmake sure PV-Storage Microgrid could regulate and control as the dispatch strategydetermined. So, tthis paper have a study on regulation and control technology ofPV-Storage Microgrid system, aiming at providing reference to further enhance thelevel of micro-grid energy management. The major work in this paper is as below:1. Based on a certain smart microgrid laboratory research platform, establish themodels of each part of PV-Storage Microgrid system. Thereinto, the PV arrays aremodeling by the engineering simplified models; Storages consist of storage batteriesapplying Kinetic Battery Model(KiBaM); the converter starts from its main circuit toestablish its model in the dq coordinate; the control system model consists ofMaximum Power Point Tracking (MPPT), storage batteries charge-discharge control,and power factor control of the convert.2. Taking DPVG in a certain smart microgrid laboratory for the study object,establishing a short-term forecasting model of photovoltaic generation power basedon improved BP neural network. The model applies improved BP neural network as forecasting method, uses the selected historic sequence generation of similar day,meteorological information, and the weather forecast information of the forecast dayas the network input.3. Have a simulation study on regulation and control of PV-Storage microgridsystem under different dispatch strategies. Based on the model of each part of thePV-Storage microgrid system, establish the model of the whole system, and simulateon regulation and control of PV-Storage microgrid system under two dispatchstrategies. One is strategy aiming at enhancing energy efficiency of DG in themicrogrid, and the other is economic dispatch strategy considering time-of-use priceand PV generation power forecasting.