基于定子磁链自适应观测的永磁同步电机直接转矩控制系统

Permanent Magnet Synchronous Machines Direct Torque Control System Based on Adaptive Stator Flux Observer

为了克服系统的时变性及在系数矩阵中的参数确切值未知的情况下也能实现对永磁同步电动机定子磁链的准确观测,提出了基于模型参考自适应的永磁同步电动机定子磁链观测方法。将电机运行过程中变化最大的参数——定子电阻作为可变参数,以定子磁链为状态变量的电机状态方程作为参考模型,将定子磁链状态观测器作为可调模型,通过对定子电阻自适应律的推导得出定子磁链自适应观测器。通过自适应观测器与全维状态观测器对永磁同步电动机定子磁链观测效果的对比发现:自适应观测器对定子磁链观测的准确度更高、对定子电阻等电机参数变化的鲁棒性更强。

The accurate observer and effective control of flux have significant sense to the performance improvement of direct torque control system. Full order observer has been used to observe stator flux with good performance achieved, but the design of stator flux full order observer is based on the assumption that the system of permanent magnet synchronous machines（PMSM） is a linear and invariable system. In practical, some parameters of motors will change during the motor running, so the system of PMSM is a variable system but not a invariable system. So the error of flux cannot be tended to zero while the design of flux full order observer based on invariable system. In order to observe stator flux accurately even when the parameters of the coefficients are not know, an adaptive stator flux observer is put forward. The simulation and experiment results obtained by using adaptive stator flux observer are compared with that got from full order state stator flux observer, which has proved that adaptive stator flux observer can observer stator flux more accurately and has better robustness to parameters variation.