Study on high stable measurement techniques for campbell fission chambers

Dynamic characteristics of Campbell fission chambers will change while in operation, due to the impacts of such microscopic mechanisms as capturing of electrically negative molecules, which could potentially result in measurement outputs significantly deviating from the true reactor power. To avoid the above mentioned negative impacts on reactor safety, time-frequency impulse response models are established for fission chambers, and the mapping relationship between microscopic processes and frequency characteristics are well studied. The signal processing method of band-pass filtering is therefore introduced to improve performance of tradition measurement systems and limit the Campbell measurement within the range of electron drift zone, thus achieving highly stable measurement under complicated changing conditions. (author)