ESTIMATION OF UNKNOWN STATES FOR AN ELECTRIC WATER HEATER WITH THERMAL STRATIFICATION AND USE OF SAME IN DEMAND RESPONSE AND CONDITION-BASED MAINTENANCE

摘要

A water heater that includes a cylindrical storage tank, at least one heatingelement,and at least one temperature sensor is modeled using a one-dimensional modelthatincludes: a vertical stack of disks representing the water volume in thecylindricalstorage tank, and a stack of annular segments surrounding the vertical stackofdisks. The stack of annular segments represents the cylindrical wall of thecylindricalstorage tank. The one-dimensional model may be used by a condition-basedmaintenance system comprising an electronic data processing device configuredtodetect a failure mode present in the water heater based on an output of thewaterheating model component. Some illustrative failure modes include insulationdisturbance, heating element failure, excessive sediment buildup, or a driptuberupture.