Measurement of the reactor dynamic characteristics utilizing the pseudorandom oscillation technique

This paper describes the measurement of frequency response in HFETR at power. It is performed by using Pseudo-Random Binary Sequence (PRBS) as excitation signal to drive reactor control rod and then introducing small reactivity perturbation. The test data have been analysed using the cross-correlation technique on samll digital computer. The dynamic reactor parameters have been obtained by means of a simplified theortical model fitting measurement curves, such as temperature coefficient of reactivity for fuel and moderator and their time constants