Newton-Raphson based computation of id in the field weakening region of IPM motor incorporating the stator resistance to improve the performance

This paper presents a high precision calculation of d-axis stator current, i_d to improve the performance of interior permanent magnet synchronous motor (IPMSM) drive over wide speed range for high performance industrial drive applications. The Newton-Raphson method (NRM) is used for computation of flux component of stator current, i_d. Traditionally, the stator resistance is neglected to calculate i_d in the flux weakening region. The power capacities of the motor and the inverter are considered in developing the control algorithm. The efficacy of the proposed NRM based computation of i_d for IPMSM drive is evaluated in simulation at different operating conditions. The performance of the IPMSM drive with the proposed NRM method is also compared with the conventional calculation of i_d.