Interconnected Disturbance Observer-Based Tracking Control for Permanent Magnet Synchronous Motors
Zhengguo Huang, Mou Chen, Mihai Lungu
Abstract
The novel interconnected disturbance observer (IDO) is proposed in this brief to tackle the mismatched and matched disturbances which may affect the speed control of the permanent magnet synchronous motor (PMSM). The designed IDO is composed of multiple disturbance observer (DO) pairs (DOPs), where each disturbance observer pair is constructed by two single DOs (SDOs) and is dependent on the same interconnected variable. For the IDO of PMSM, the positive definiteness of the observer gain in the DOP is not essential due to the designed structure of the IDO. In addition, weighting the DO gains in the DOP improves the disturbance estimation performance of the above IDO. Through analytical solutions of differential equations, the stable region and the decay rate of the disturbance estimation error (DEE) of the IDO for PMSMs are compared with that of the SDO. Besides, boundedness conditions of the DEE and tracking errors are also discussed. Finally, the effectiveness of the IDO-based controller (IDOBC) is verified by the experiment with TMS320F28335 DSP.