Load Torque Observer Based on $\mathcal{H}_{\infty}$ Filter with Eigenvalue Constraints for Permanent Magnet Synchronous Machine

This study addresses the load torque estimation problem in permanent magnet synchronous motors (PMSMs) by proposing a novel observer design methodology that integrates an $\mathcal{H}_{\infty}$ filter with eigenvalue constraints. The design framework systematically reconciles the trade-off between transient convergence rate and stochastic noise rejection through eigenvalue spectrum shaping of the observer error dynamics and frequencydomain optimization of the noise propagation channel. The simulation result approved the validity of studied method.