Page - 199 - in Short-Term Load Forecasting by Artificial Intelligent Technologies

Energies2018,11, 1948 productionof1L/min[24]. Theelectrolyzerhas fouroperationmodes:warmup,production, standby, andshutdown.WedevelopedahydrogenelectrolysismodelusingtheMatlab/SimPowerSystemTM andappliedthe followingmanagementstrategies (seeFigure4b): 1. Warmup:Theextra-renewableenergy is regardedasredundantenergywhenthebatterySOCis greater thananupper limitof95%. 2. Production: The electrolyzer is switched on after 10 min, when the integrated redundant renewableenergy ∫10 0 (Prenew−Pload)dt increases. Prenew andPload represent thepowersources fromtherenewableenergyandpowerconsumptionof the loads, respectively. 3. Standby:Theelectrolyzerisswitchedoffwhenthehydrogentankisfull(reachesthehigh-pressurelimit). 4. Shutdown:Thehydrogenelectrolyzer isswitchedoffwhenthebatterySOCfalls to the lower limitof85%. Toavoidfrequentswitching, theelectrolyzer isallowedtoproducehydrogenwhenthebattery SOCisbetween85%and95%. (a) System layout. (b) Management strategy. 3UHVVXUH+ ġ 0DVV+ ġ $& 3RZHUġ +\GURJHQ VWRUDJH +\GURJHQ SURGXFWLRQ : +\GURJHQġ (OHFWULFLW\ġ ,JHQHUDWRUġ Figure4.Thehydrogenelectrolyzationsystem. A3Lhydrogencylinderwasusedtoconducttheelectrolyzationexperiments.Theresultsareshownin Figure5,wheretheinitialandfinalpressuresofthecylinderare8.6barand10bar,respectively.Asacheck 199