ABB Review Special Report - ABB - ABB Group

Reactive power [pu]Inductive Capacitive51.510.50-0.5-1-1.5reactive power from or supply reactivepower to the grid. Each of these modesis possible with the DC link voltagevarying as the battery’s charging conditionchanges.The operating range of the system interms of active and reactive power for90% and 100% of the nominal grid voltageis shown in 5 .6Operating range of BESSP/Q diagram1 pu corresponds to 40 MVA-1.5 -1 -0.5 0 0.5 1 1.5ChargeDischargeActive power [pu]= V_grid = 100% = V_grid = 90%Overview of control and protection systemThe control systemLocal system control is provided by anABB SPIDER MicroSCADA humanmachine interface (HMI) based on theMicrosoft Windows operating system 6 .The system is operated via pictures,windows and function keys using amouse and a keyboard. Sequence andclosed-loop control as well as overallprotection are provided by ABB’sprogrammable high-speed controller(PHSC), which can be programmedusing the graphic function plan programFUPLA. The PHSC is well provenand its reliability has been shown to besuitable for both system control andprotection in numerous applications.The converter control incorporates thefollowing functionality:Sequence controlControl of the main breakersSignal conditioningProcessing of measurement signalsFast current control for ride-throughin the event of external faultsPower and reactive power controlLoad managementInterlocking of local control andSCADA/RTU controlRedundant protection functionsBESS – a stabilizing factorWhile fulfilling its overall mission ofreducing power outages in the Fairbanksarea, the Alaskan BESS has specificbenefits in the areas of transmission anddistribution, generation and strategicplanning:Transmission and distribution benefitsinclude voltage regulation, first swingstability and loss reduction.In the generation area the BESS offersspinning reserve, ramp-rate constraintrelief, load following, black starts, loadleveling, and a reduction in deferredturbine starts.Strategic benefits include improvedpower quality, reduced demand peaks,and enhanced service reliability throughreduced power supply generated outages.The principal benefit, however, isthe ability of the BESS to instantly contributeto system stability following theloss of a major transmission line orgenerator. The spinning reserve it provideshas the potential to allow generationunits to be run at lower levels orbe shut down entirely, resulting in significantsavings. Almost instantaneousactive power is available. This is importantin cases where the BESS has toramp up before the impact of a generatorloss becomes noticeable at the pointof common coupling.Battery monitoringsystemLocal HMI(ABB MicroSCADA)GVEA SCADARTUProgrammable High Speed ControllerProtectionTim DeVriesGolden Valley Electric Associationtrdevries@gvea.comControlConvertercooling unitJim McDowallSAFTjim.mcdowall@saftamerica.com118Battery stringConverter Transformer 138 kVswitchgear138 kV gridNiklaus UmbrichtGerhard LinhoferABB Automation TechnologiesCH-5300 Turginiklaus.umbricht@ch.abb.comgerhard.o.linhofer@ch.abb.com46Special ReportABB Review