Experimental comparison of the performance of PI and IP controllers for a field-oriented controlled permanent magnet synchronous motor drive

Permanent magnet synchronous motors are used in various high-performance applications with many control algorithms, each of which has its advantages and disadvantages. One of the most widely used control methods for this motor type is the Field-Oriented Control. Associated with a space vector modulation-controlled inverter, this approach has numerous advantages, including its rapid current and torque response and fixed switching frequency. The most used regulator for this control method is the PI regulator. However, this regulator exhibits an overshoot that may negatively affect the whole control loop. The IP structure can theoretically solve this problem without any further computation. This study presents an experimental comparison between the PI and the IP structures of linear controllers in a vector-controlled permanent magnet synchronous motor (PMSM) drive with space vector modulation. The results show that the IP regulator significantly reduces the overshoot compared to the PI regulator while effectively dampening load disturbances. The experimental results also show that the IP regulator exerts minimal current demand during motor start-up, minimising perturbations. Additionally, the direct current remains close to the reference value with both regulators, despite the greater initial perturbations in the PI regulator. These findings highlight the IP structure's superiority in mitigating overshoot and enhancing the overall performance of the vector-controlled PMSM drive. This study provides new insights into the advantages and limitations of the PI and IP. The observed reduction in overshoot and the disturbance rejection capabilities of the IP regulator demonstrate its potential to enhance the control loop stability and overall system performance.