Method and device for determining a level of noise and electromagnetic vibrations

A method for determining a noise and vibration level of electromagnetic origin of an electric motor machine (1) having a mechanical structure, said machine (1) comprising a rotor (11) and a stator (12), said rotor (11) and said stator (12) being separated by an air gap, said method being implemented by at least one processor, said method comprising the following steps:

• obtaining (31) first data representative of a set of loading cases associated with said machine (1), each said loading case corresponding to a component of a magnetic loading according to a decomposition on a mathematical basis;
• obtaining (32) second data representative of a set of eigenmodes of said mechanical structure;
• determining (33), from said set of loading cases and said set of eigenmodes, a subset of loading cases and significant eigenmodes;
• obtaining (34) third data representative of a set of relevant nodes associated with said mechanical structure;
• computing (35) a set of frequency response functions, by modal expansion restricted to said set of relevant nodes and to said subset of loading cases and significant eigenmodes;
• obtaining (36) fourth data representative of a first set of operating points of said machine (1), each said operating point being associated with a torque and a speed of said machine (1);
• obtaining (37) fifth data representative of a set of magnetic states of said machine (1), each said magnetic state of said set of magnetic states being associated with an operating point;
• determining (38) a set of operational loadings from said set of magnetic states;
• and
• determining (39) information representative of a noise and vibration level of electromagnetic origin of said machine (1) from said set of operational loadings and said set of frequency response functions.