Objectives

During electrical machine start-up, quick variations of electrical currents may occur and vibroacoustic calculations can no longer be calculated assuming steady state. This module of MANATEE software enables e-NVH calculations in time domain with arbitrary rotor position waveform and current waveforms.

Description

The module calls MANATEE models in full transient mode, without assuming that steady state is reached at each speeds. Currents and rotor angle are therefore specified as time waveforms during whole run-up. All variable speed post processing of LAB.VS are then available, performing STFT instead of FFT. It is especially useful when coupling MANATEE to a Simulink control block.

Example of noise spectrogram obtained by MANATEE transient mode on EV HEV NVH application

Technical details

Contrary to quasi static approach of VS.QS module, all the quantities are here assumed to be always varying and a Short Time Fast Fourier Transform is used.

Graphical post-processing

The complete list of plot commands is available on MANATEE plot commands webpage. The following visualizations are more particularly related to this module:

• A-weighted sound pressure level spectrogram (plot_VS_ASPL_spectrogram)
• Order analysis (plot_VS_ASWL_order_analysis)