Performance Evaluation of a PI-Based PMSM Electric Vehicle Drive Under Dynamic Passenger Loading and Road Grade Variations

Growing concerns about climate change and greenhouse gas emissions have accelerated the development of electric vehicles (EVs) as a sustainable transportation solution. It has intensified interest in high-performance and energy-efficient traction systems. Among the available motor technologies, Permanent Magnet Synchronous Motors (PMSMs) are widely employed due to their high efficiency, power density, and dynamic characteristics. Although the performance of PMSM drives have been widely studied, research often uses simplified load torque disturbances, which may not accurately reflect actual vehicle operating conditions. The combined effects of dynamic passenger loading and road grade variations remains insufficiently investigated. In practice, traction systems are continuously affected by variations in vehicle load and road grade. This study assesses mainly the performance of a Proportional-Integrator (PI) controlled PMSM based electric vehicle under simultaneous dynamic passenger loading and road-grade variations, representing realistic loading conditions. A vehicle model integrated with a Field Oriented Control (FOC) strategy is developed, in which dynamic passenger loading, road grade variations, and combined operating scenarios are considered. The comparative analysis suggests higher torque demand, current and energy consumption under combined scenario, with highlighting a potential trade-off between speed-tracking and energy efficiency. The proposed approach aims to provide a more realistic assessment of PMSM-based electric vehicle drives by considering operating conditions that are closer to those encountered in everyday use. The obtained results establish a performance basis for future comparison with advanced control strategies.