Interior magnet machine design with low core losses

An apparatus for estimating core loss in an electric motor using a finite element analysis (FEA) simulation, the apparatus comprising:

• means for creating, modifying, or receiving a FEA model to represent at least one portion of an electric motor in a computer system, the computer system comprising a user interface and a processing circuit configured for FEA simulations, the electric motor comprising at least one rotor capable of rotation about a rotational axis and a stator having at least one pole pair disposed radially about the rotational axis of the rotor;
• means for placing at least one coil at a first location within the rotor iron or stator iron of the motor in the FEA model, the coil comprising a wire loop;
• means for calculating a time-domain flux density B of the at least one coil as a function of time;
• means for converting the calculated flux density function to a frequency-domain spectrum;
• means for receiving material core loss parameters for at least some frequencies indicated by the frequency-domain spectrum;
• and
• means for determining a core loss of the at least one portion of an electric motor by a weighted combination of the received material core loss parameters according to the relative magnitudes of the peaks in the discrete frequency-domain spectrum.

A computer program product for processing data for a program configured to estimate core loss in an electric motor using a finite element analysis (FEA) simulation, the computer program product comprising:

• a non-transitory computer-readable medium having stored thereon code for causing processing circuitry to:
• enable a user to create, modify, or receive a FEA model to represent at least one portion of an electric motor in a computer system, the computer system comprising a user interface and a processing circuit configured for FEA simulations, the electric motor comprising at least one rotor capable of rotation about a rotational axis and a stator having at least one pole pair disposed radially about the rotational axis of the rotor;
• enable placement, with the user interface, of at least one coil at a first location within the rotor iron or stator iron of the motor in the FEA model, the coil comprising a wire loop;
• calculate a time-domain flux density B of the at least one coil as a function of time;
• convert the calculated flux density function to a frequency-domain spectrum;
• receive material core loss parameters for at least some frequencies indicated by the frequency-domain spectrum;
• and
• determine a core loss of the at least one portion of an electric motor by a weighted combination of the received material core loss parameters according to the relative magnitudes of the peaks in the discrete frequency-domain spectrum.