Entwicklung kapazitiver Sensormessprinzipien zur Enthalpiebestimmung in Sorptionsspeichern

Through dehumidifying sorptive materials are able to store thermal energy, the supplied energy will be stored in thermochemical heat storages until the material is humidified again. For the application of such intended heat storage systems it is indispensable to know the charge state of the storage system. Up to date there is no reliable and feasible treatment to determine the current charge state of heat storage systems based on sorptive materials. Within the research project SenSOR of the research group ASiC at the University of Applied Sciences Upper Austria such a sensor, to gather the actual charge state, will be developed. The correlation between the current charge state and the moisture content of the sorptive material is utilized, the actual moisture content is being determined by means of a capacitive measuring principle based on a resonant circuit. Within a empirical study occurring cross sensitivities are beeing analyzed. Subsequent to system identification as a Hammerstein-Wiener model detected cross sensitivities are used for correction of dynamic measurement errors. Up next, the comparison of three examined sorptive materials including a discussion of different material characteristics, e.g. the actual moisture content of the sorptive material as a function of measured capacity, is shown. The proof of correlation between the gravimetric weight measurement and the capacitive measuring principle of the moisture content of sorptive materials is provided and delivered satisfying results.