[en] The problem of closed orbit corrections in synchrotrons is consdidered. An algorithm of the closed orbit correction during the cycle of acceleration is proposed. In this algorithm the form of the functional, that has to be minimized, is analytically deduced, and differs from those accepted by other authors. On the basis of the spectral analysis of chance functions an expression for the quality of correction is drawn. These results are used for the heavy ion synchrotron (HIS) in accelerating complex project. The deviation of the HIS closed orbit is calculated. The position and the necessary strength of the correcting dipoles and pickup electrodes are chosen