An Active Power Control Scheme For Isolated Network Which Included Wind Turbine, Pv, Diesel And Battery Based On Stratified Control

As the electricity load has dispersion, diversification and other requirements,which increases the grid construction and maintenance costs as well as the difficulty ofcontrol. The isolated network technology is an effective way to solve the problemmentioned above. The isolated network can integrate varieties of distributed powergeneration as a system to supply power for local load, this technology has been moreand more attach attention, not only to solve supply problems in remote areas, but alsocan make full use of the advantages of renewable energy, and promote the developmentof renewable energy. In this paper, for the purpose of improving the load power supplyreliability, making full use of renewable energy and improving the quality of powersupply, it’s important to expand research isolated network which included wind turbine,PV, diesel and battery.The isolated network involves diversity of distributed power, moreover therenewable energy has characteristic of intermittent, volatility ect, system of energysupply and demand imbalance have a great influence on the isolated network securityand stability, quality of power supply, which is a key factor to limit the development ofthe isolated network. The research in this paper starting from the isolated networksystem stability control, put forward the master-slave control structure. According to thedifferent feature of the micro-power select appropriate control method, including PQcontrol and V/f control. PQ control can supply stability output power and V/f controlguarantee the stability of the voltage and frequency of the micro-power output. So byways of master-slave control structure, selecting the appropriate main power andcoordination of micro-power output can ensure the safe and stable operation of thesystem.On the basis of isolated network security and stability, considering variety ofpower relationship between the system and load demand, this paper proposed a way toreduce the energy storage battery charge and discharge times to protect the storagebatteries, introducing the renewable energy forecasting to reduce the error betweendistribution power and actual power, what’s more can make full use of renewable energy and reduce the number of start and stop times. This strategy can ensure thequality of the system power supply and maintain energy supply and demand balance.Through DIgSILENT simulation software to build isolated network simulation, theresults illustrate that the strategy can according the load demand, timely adjust theoutput of micro-power to ensure the quality of the system power supply, verify thestrategy mentioned in this paper is effective.