The invention discloses a multi-fault-feature identification method based on a sparse multiperiod-
group lasso. The multi-fault-feature identification method comprises the following steps that an to-be-identified
signal is analyzed so as to construct a binary periodic sequence b, based on a fault feature
signal, the between-group sparse characteristic in period groups are presented to obtain a regularization term P (x;b) for promoting between-group sparseness in the period groups, and a sparse multiperiod-
group lasso model is established based on discrimination of different fault feature frequencies; controlled optimization operators of a data fidelity term (please see the specifications for the formula) and the regularization term (please see the specifications for the formula) in the sparse multiperiod-
group lasso model are constructed correspondingly, through decoupling of the controlled optimization operators, variables are separated, aiming at each controlled optimization operator,the closed-
form solution optimized by the controlled optimization operator is established, through iteration, the closed-
form solution corresponding to the controlled optimization operator of each fault is solved, and thus model solving is achieved; regularization parameters are set adaptively through
simulation signal counting and analyzing, the adaptive solution of the
algorithm is obtained through the parameters, and thus each fault is obtained through separation; and aiming at each fault obtained through separation, the fault type is identified through envelope analysis.