Performance Analysis of Field Oriented Control Under Parametric Variations of a PMSM

Permanent magnet synchronous motors (PMSM) are widely used in traction applications due to their high torque-to-mass ratio. In this context, field-oriented control (FOC) is the typically applied control algorithm and its use has been extensively researched. According to several authors, variations in motor parameters due to thermal or mechanical stress can lead to a degradation of the dynamic response of the speed and torque of PMSMs controlled by FOC. However, previous studies on variations of motor parameters were limited, focusing on a narrow range of operating points and using atypical variation percentages that did not reflect the intended applications. With the objective of identifying the parameters that more drastically affect controller performance, this study provides a simulationbased evaluation of torque response time, overshoot, and settling time at predefined operating points on the torque-speed curve, including near zero speed, base speed, and speed in the fieldweakening region, based on the maximum torque per ampere approach and considering parameter variations of up to $30 \%$ in d and q inductances, phase resistance, and permanent magnet flux. The results indicated that variations in the d and q axis inductances, flux linkage, and phase resistance collectively account for $49 \%$ of the observed variability greatly degrading dynamic performance. Inductances were identified as the parameters that have the greatest impact on the variability of dynamic response.