MANATEE software | e-NVH Algorithms |
---|---|

Sub-module |
ALG.LIA |

Function |
Load Interplation Algorithm (LIA) |

Validation |
ALG_049 |

See also |
ALG.LEA Load Extrapolation Algorithm |

### Objectives

The accurate calculation of noise and vibrations of electric motors requires to evaluate their **vibro-acoustic behaviour at variable speed, taking a high number of speed steps** to correctly catch structural resonances. This usually represents a high computational load, as operational magnetic loads must be updated at each operating point.

Especially for traction application, the knowledge of the operating cycle in advanced design stages enables to speed up the calculation of operational magnetic loads using Load Interpolation Algorithm (LIA) implemented in MANATEE software. Using LIA, operational magnetic loads can be obtained much faster by computing the loads on some key operating points chosen by the user and then interpolate on the full operating cycle.

**Illustration of Load Interpolation Algorithm used in MANATEE**

### Description

Load Interpolation Algorithm (LIA) consists in calculating air-gap Flux density Look Up Table at different excitation (Id,Iq) or as a function of speed. The flux density look up table allows to quickly calculate magnetic forces and torque ripple including saturation effects, which can be reused in SOL.SKEW for skew optimization or ALG.EVS for spectrogram synthesis or VAR.QS for variable speed NVH calculations. MANATEE built-in projection algorithm allows to reliably convert airgap Maxwell stress to stator tooth magnetic forces.

### Technical details

Load Interpolation Algorithm (LIA) is the most relevant when coupling MANATEE with FEMM using EM3 modules. All variable speed post processing are available when using LIA.

### Graphical post-processing

The complete list of plot commands is available on MANATEE plot commands webpage.