Power Saving and Sensorless Vector Control Method in IPMSM Drive

Abstract

An enhanced sensorless vector control method for an Interior Permanent Magnet Synchronous Motor (IPMSM) drive, with a primary focus on improving power efficiency, rotor position estimation without mechanical sensors, and ensuring operational robustness under voltage disturbances like sag and swell. The system employs Field Oriented Control (FOC) integrated with a closed-loop observer in MATLAB/Simulink to estimate the rotor speed and position using stator current and voltage feedback. This eliminates the need for traditional back-EMF-based estimation or mechanical sensors. A power-saving mechanism is introduced to reduce unnecessary energy consumption by dynamically adjusting inverter switching based on load demand. Furthermore, the system includes a voltage sag/swell detection strategy to maintain stable motor performance under grid disturbances. Simulation results demonstrate effective sensorless operation, efficient energy consumption, and robustness under dynamic load and input conditions.

Introduction

Interior Permanent Magnet Synchronous Motors (IPMSMs) are favored in electric drives for their high efficiency, power density, and precise control. Traditional vector control depends on mechanical sensors for rotor position feedback, which increase cost and reduce reliability. To address this, the study proposes a sensorless vector control strategy implemented in MATLAB/Simulink, aiming to save power, eliminate mechanical sensors, and enhance robustness against voltage sags and swells.

The simulation integrates two systems: sensorless vector control of the IPMSM using Field-Oriented Control (FOC), and a Dynamic Voltage Restorer (DVR) to compensate for voltage fluctuations. The system converts three-phase voltages through Clarke and Park transformations to independently control torque and flux. Proportional-Integral controllers regulate current components, and Space Vector PWM generates inverter signals to drive the motor. The DVR injects compensating voltages during power quality disturbances.

Simulation results demonstrate stable speed and torque under varying loads, accurate rotor position estimation without sensors, and effective voltage sag and swell compensation, confirming the system’s robust performance and enhanced reliability in dynamic conditions.

Conclusion

This paper demonstrates a sensorless vector control system for IPMSM drives with power-saving features and voltage disturbance handling. The model-based estimator provides accurate rotor information without mechanical sensors. The power optimization strategy and sag/swell compensation increase system efficiency and robustness, making it suitable for industrial applications requiring high reliability and compact design.

References

[1] Zhang, G.; Wang, G.; Xu, D.; Yu, Y. Discrete-time low-frequency-ratio synchronous-frame full-order observer for position sensorless IPMSM drives. IEEE J. Emerg. Sel. Top. Power Electron. 2017, 5, 870–879. [2] Liang, D.; Li, J.; Qu, R.; Kong, W. Adaptive second-order sliding-mode observer for PMSM sensor-less control considering VSI nonlinearity. IEEE Trans. Power Electron. 2018, 33, 8994–9004. [3] Quan Yin1, Haichun Li, Hui Luo, Qingyi Wang and Chendong Xu. An Improved Sensorless Vector Control Method for IPMSM Drive with Small DC-Link Capacitors. School of Automation, Huazhong University of Science and Technology, Wuhan 430000, China. 2 January 2020; Accepted: 22 January 2020; Published: 26 January 2020.

Copyright

Copyright © 2025 K Uma Rani, Shruthi Kotha, Punarvi Rochisha Ketha, Naveena Uppari. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.