Extraction of the Sampled High-Frequency Current Trajectory with a Novel Synchronous Minor Sampling Process in IPMSM Using PWM Carrier-Synchronized Voltage Injections

A high-frequency signal voltage injection method incorporating a newly introduced synchronous minor sampling method can enhance the resolution and time resolution of AD conversion by employing appropriate post-processing techniques. In this study, a first-order complex bandpass filter was utilized as a post-processing method for extracting the responsive high-frequency signal current. The extracted current trajectory was observed to exhibit an ellipsoidal shape, and its long-axis angle was calculated on the complex plane. This angle is employed to enhance the position estimation performance of the rotor.