TheUKGovernmenthasadeclaredtargetthatrenewableenergyshouldprovide15%ofUKelectricitysuppliesby2015[1].CurrentlyintheUK,applicationsforconnectionhavebeenmadeforover15GWofwindonshorewindgenerationandlicenceshavebeenawardedtodevelopersforanadditional7.2GWofwindpowerlocatedoffshore[2,3].Atpresent,mostwindturbinesarebasedoninductiongenerators.However,thedynamiccharacteristicsofaninductiongeneratordiffermarkedlyfromthoseofasynchronousgenerator,andconsequentlythebulkreplacementofconventionalgenerationbywindfarmswillhaveeffectsonetworkoperationanddynamicbehaviour,whichneedtobeaddressedproperly[4,5].Infuture,manylargewindturbines(installedeitheroffshoreoronshore)willoperateatvariablespeedusingdoublyfedinductiongenerator(DFIGS)owingtotheirabilitytomaximisepowerextraction,theirflexibilityofcontrolandtheircapabilityfornetworksupport[6–8].TheDFIGsflexibilityofcontrolofferstheabilitytomanipulatethedynamiccharacteristicsoftheDFIGpresentedtothenetwork.Consequently,onewayofensuringthattheintroductionofbulkwindgenerationdoesnotchangenetworkdynamiccharacteristicsdrasticallyistoaimtoprovideawindfarmwithadynamiccharacteristicsthatissimilartothatofaconventionalsynchronous-generator-basedpowerstation.
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