### Principle

For variable speed applications, especially for automotive applications such as Hybrid Electric Vehicles and Full Electric Vehicles, it is convenient to calculate the **NVH behaviour of the electric powertrain in the torque/speed plane**.
This way, the acoustic noise / vibration / harmonic forces at any operating point can be obtained and the noise can even be synthesized along a driving cycle. Besides the NVH difference between braking and traction can also be observed.

Building acoustic noise maps requires to specify the current angle as a function of speed for each torque level, which depends on the chosen control strategy (e.g. MTPA). Two definitions are possible:

- define the matrices T(N,I) and T(N,Phi0) (torque level T function of phase current level I, speed N and current angle Phi0) , Id & Iq currents function of torque level and speed - see the templace of Excel sheet in
*Test/Validation_data/InputNoiseMapTemplate.xlsx* - define the matrices Id(T,N) and Iq(T,N) (Id & Iq currents function of torque level T and speed N) - see the templace of Excel sheet in
*Test/Validation_data/InputNoiseMapTemplate2.xlsx*

In these matrices unknown values can be left empty.

### Scripting implementation

To activate the calculation of the acoustic noise map one must choose respectively for input type 1 and 2

`Input.Simu.type_noise_map=1;`

`Input.Simu.type_noise_map=2;`

The noise map is automatically run at the end of the fixed speed simulation. To display the acoustic noise map one can type the following plot commands:

`plot_VS_ASWL_map`

It gives the following type of graph:

For further details see the dedicated page on plot_VS_ASWL_map plot command.

### GUI implementation

TBC

### See also

NVH maps are carried in validation cases ALG_038 and ALG_39.