The Sensorless Control of CSI-Fed PMSM Drives Based on a High-Order SMO

The article verifies a sensorless control strategy for current source inverter (CSI)-driven permanent magnet synchronous motor (PMSM) using a high-order sliding mode observer (SMO), specifically applicable in the medium to high speed range. The CSI, known for its motor-friendly output waveform with low dv/dt, addresses the issue of motor terminal overvoltage under long cable conditions. PMSMs, characterized by their high power density, have garnered attention in the field of long-line operations, with expectations of replacing induction motors. However, their drive requires rotor position information for decoupling torque and excitation components. This article validates the feasibility and superiority of using a high-order SMO to improve position observation convergence speed and reduce steady-state error in the sensorless control of CSI-fed PMSM drive system. Simulation of the control system for CSI-fed PMSM drive supports the proposed methods.