Active control of planetary gearbox vibration using phase-exact and narrowband simultaneous equations adaptation without explicitly identified secondary path models

Abstract

Abstract So far only model-based approaches have been proposed for active control of planetary gearbox vibration. However their performance depends strongly on the quality of the used models. To overcome this problem a novel algorithm which is based upon the narrowband simultaneous equations adaptation is proposed. It requires no offline identified secondary path model and belongs to the class of direct adaptive feedforward control algorithms. The investigation reveals that a phase-exact implementation in which an incremental encoder is used to generate synthetical reference signals is required. No feedback between algorithm output and reference measurement occurs. Performance and robustness of the proposed algorithm is compared to the common model-based FxLMS algorithm in simulation and experiment. It achieves comparable convergence speeds and vibration reductions. However in contrast to FxLMS it is able to compensate for changes in the secondary path. A test rig for small planetary gearboxes is presented. Internal forces caused by gear meshing can be measured. In one of the experiments 112 vibration orders are controlled with a mean reduction of 72%. The proposed active vibration control setup consumes 22\u202fW of electric power and thereby degrades the planetary gearbox efficiency by only 0.2% for the experimentally examined operating point.