【目的】在永磁同步电机无传感器控制系统中，传统全阶滑模观测器(FOSMO)采用固定滑模增益，无法同时兼顾系统在宽速域内的动态响应速度与稳态性能，导致电机在低速运行时产生严重的系统抖振，从而降低了转子位置及转速的观测精度。【方法】为了解决上述矛盾，本文提出一种基于电流误差与估计转速的自适应FOSMO，根据系统实时运行状态动态调节滑模增益，实现不同工况下增益的平滑调节，从而增强系统动态性能与稳态精度。此外，为进一步抑制高频开关带来的抖振现象，引入连续平滑的tanh函数替代传统的sign函数。同时，利用李雅普诺夫稳定性理论对改进后的观测器进行数学推导，证明了观测器的收敛性。【结果】通过仿真和试验对所提自适应FOSMO的观测性能进行验证。结果表明，与传统FOSMO相比，本文所提自适应FOSMO在低速域的扩展反电动势波形与转速波形的抖振得到明显抑制，转子位置估计误差显著降低，观测精度更高。【结论】在所提自适应FOSMO下，系统抖振得到显著抑制，系统整体稳定性得到提升，且自适应FOSMO的适用速域更宽。

[Objective] In the sensorless control system of permanent magnet synchronous motors, the traditional full-order sliding mode observer (FOSMO) adopts a fixed sliding mode gain, which fails to simultaneously balance the dynamic response speed and steady state performance of the system over a wide speed range. This leads to severe system chattering during the low speed operation of the motor, thereby reducing the observation accuracy of the rotor position and speed. [Methods] To address the aforementioned contradictions, this paper proposed an adaptive FOSMO based on current error and estimated speed. The sliding mode gain was dynamically adjusted according to the real-time operating state of the system, achieving smooth regulation under different operating conditions, thereby enhancing the dynamic performance and steady state accuracy of the system. Furthermore, to further suppress the chattering caused by high-frequency switching, a continuous and smooth hyperbolic tanh function was introduced to replace the traditional sign function. Meanwhile, the Lyapunov stability theory was employed to conduct mathematical derivation of the improved observer, which verified the convergence of the observer. [Results] The observation performance of the proposed adaptive FOSMO was verified through simulations and experiments. The results showed that, compared with the traditional FOSMO, the proposed adaptive FOSMO significantly suppressed the chattering of the extended back electromotive force waveforms and speed waveforms in the low speed region, remarkably reduced the rotor position estimation error, and achieved higher observation accuracy. [Conclusion] Under the proposed adaptive FOSMO, the system chattering is significantly suppressed, the overall stability of the system is improved, and the adaptive FOSMO has a wider applicable speed range.

国家自然科学基金(62573010)