This article reviews six fundamental-wave excitation sensorless techniques for synchronous machines reported in the literature. All the techniques rely on a hybrid flux observer scheme, combining the voltage and current-models of the machine, and use the flux observer error signal to track the rotor phase angle and the rotational speed. A common mathematical framework with magnetic nonlinearity is constructed for the stability analysis where each of the studied technique is represented by a unique projection vector. The dynamics of the flux and the position observer is investigated and the regions of instability are identified for each scheme under similar operating conditions. Experimental validation to support the stability analysis is reported on a 1.1-kW synchronous reluctance machine test-bench.

中文翻译：

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无传感器同步电动机驱动器：使用投影矢量框架的基于磁通观测器的位置估计方案的综述

本文回顾了文献中报道的用于同步电机的六种基波激励无传感器技术。所有技术都依赖于混合磁通观测器方案，结合了电机的电压和电流模型，并使用磁通观测器误差信号来跟踪转子相角和转速。构建具有磁非线性的通用数学框架进行稳定性分析，其中每种研究技术均由唯一的投影矢量表示。研究了通量和位置观测器的动力学特性，并在相似的工作条件下为每种方案识别了不稳定区域。在1.1 kW同步磁阻电机测试台上报告了支持稳定性分析的实验验证。