The least-squares method based on coupling coefficients for reactor power distribution reconstruction

Highlights: • A least squares method based on coupling coefficients for reactor power distribution reconstruction is proposed. • The power distribution reconstruction problem is regarded as an inverse problem. • The Tikhonov regularizing operator constructed by coupling coefficients is used to alleviate the ill-posedness. • Unit 3 in Qinshan No. 2 nuclear power plant and the ACP-100 small modular reactor are used to verify the new method. - Abstract: The least-squares method based on three-dimensional coupling coefficients (LS-3DCC) was tested to determine its capability for replacing the three-dimensional coupling coefficients (3DCC) method for reconstructing the power distribution of ACP-100 which is a kind of small modular reactor (SMR). In the LS-3DCC method, the power distribution reconstruction problem is regarded as an inverse problem, and the Tikhonov regularizing operator constructed by coupling coefficients is used to alleviate the ill-posedness. Some power distribution pairs are generated to compare the LS-3DCC method and the 3DCC method, and the comparison results show that the LS-3DCC method performs better than the 3DCC method.