摘要

A method for rotor crack fault diagnosis based on variational mode decomposition(VMD) with bat algorithm (BA) optimization parameters was proposed, aiming at overcoming the difficulty in identifying rotor crack fault features. The global optimization of parameter K and penalty factor α in variational mode decomposition was carried out by applying the bat algorithm. The optimal (α, K) combination of VMD was searched by using the BA and the local minimum envelope entropy was used as a fitness function in the iteration process.The simulation results show that the BA-VMD method can achieve the adaptive acquisition of VMD parameters (α, K), and has obvious advantages in anti-modal aliasing and anti-noise interference. Finally, the displacement signal of a cracked rotor was analyzed by the BA-VMD method. The results show that the frequency spectrum processed by the BA-VMD method can fully describe the frequency characteristics of the signal, and the fault characteristics of the cracked rotor can be easily identified by the frequency structure characteristics.