This article proposes an extended state observer to broaden the stability range of conventional deadbeat controller. The proposed observer is constructed through the model of permanent magnet synchronous machine (PMSM) which considers the parameters mismatch and unmodeled nonlinear elements. For the high bandwidth of current loop, the closed-loop stability is not ensured through the stability of observer. Therefore, the effect on the closed-loop performance which is caused by the observer is analyzed through the closed-loop transfer function and proved that the deadbeat performance can be kept when the parameters are precise. Furthermore, the system robustness performance is improved through adjusting the observer gain properly when parameters mismatch exists. To ensure the closed-loop stability, H∞ norm of the transfer function is chosen as an index to determine the two gain factors of observer. The effectiveness of the proposed algorithm is verified by Simulation and experimental results.

中文翻译：

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一种提高无差拍控制鲁棒性的线性扩展状态观测器的增益设计方法

本文提出了一种扩展状态观察器来拓宽传统无差拍控制器的稳定性范围。所提出的观测器是通过考虑参数失配和未建模非线性元素的永磁同步电机 (PMSM) 模型构建的。对于电流环的高带宽，不能通过观测器的稳定性来保证闭环稳定性。因此，通过闭环传递函数分析观测器对闭环性能的影响，证明在参数精确的情况下可以保持无差拍性能。此外，当存在参数不匹配时，通过适当调整观测器增益来提高系统鲁棒性性能。为保证闭环稳定性，选择传递函数的H∞范数作为确定观测器两个增益因子的指标。仿真和实验结果验证了该算法的有效性。