An adaptive PBC strategy for SM with a time-varying load torque to track fluxand speed trajectories was proposed.The key point of this method was the identificationof terms,known as workless forces,which appeared in the dynamic equations of SM buthad no effect on the energy balance equation of the closed loop.PBC,combined withadaptive control schemes,not only preserved the advantages of PBC such as nonexistenceof singularity,but also rejected the flux and speed tracking error caused by statorand rotor resistance variation.The rotor currents of SM were estimated via a state observer.This algorithm simplified the control structure and enhanced the robustness of thecontrol system.The feasibility and effectiveness were confirmed by experimental resultsbased on dSPACE. An adaptive PBC strategy for SM with a time-varying load torque to track flux and speed trajectories was proposed. The key point of this method was the identificationof terms, known as workless forces, which were in the dynamic equations of SM buthad no effect on the energy balance equation of the closed loop. PBC, combined withadaptive control schemes, not only preserved the advantages of PBC such as nonexistence of singularity, but also rejected the flux and speed tracking error caused by statorand rotor resistance variation. The rotor currents of SM were estimated via a state observer. This algorithm simplified the control structure and enhanced the robustness of thecontrol system. The feasibility and effectiveness were confirmed by experimental results based on dSPACE.