An SOGI-Based Cross-Coupled Filtering Method for Speed and Position Estimation in Low-Cost PMSM Drives Using Hall-Effect Sensors

The extraction of high-resolution rotor position and speed from the Hall signals of permanent magnet synchronous motors (PMSMs) can be achieved through a filtering process based on second-order generalized integrators (SOGIs) and a phase-locked loop (PLL). This article proposes a novel SOGI-based cross-coupled PLL (CCSOGI-PLL) method that incorporates a notch coefficient, d, to enable arbitrary tuning of the notch filter for negative sequence components. The article also presents an investigation of the corresponding parameter design. Furthermore, the combined effect of permanent magnet and Hall device installation errors is analyzed, demonstrating that the proposed filtering approach is a viable alternative to complex compensation schemes. To facilitate implementation in low-cost drivers, the article develops an implicit Tustin discretization method for stable filtering across a wide frequency range and introduces a state presetting technique to enhance stability during startup and bidirectional operations. The effectiveness of the proposed strategy is experimentally verified on a 0.75 kW treadmill motor.