In surface-mounted permanent magnet synchronous motor (SPMSM) low-speed sensorless control, the high-frequency sinusoidal voltage injection method for rotor position estimation is affected by the low saturation salient rate of SPMSM and the system delay, resulting in estimation error. This article proposes a dual-demodulation method utilizing the high-frequency positive- and negative-sequence stator current of the motor. This method is based on the principle of maximizing the effect of the salient inductance component and minimizing the significant component of noise, which improves the utilization of the current containing angle information and increases the signal-to-noise ratio of the position angle error fed to the rotor position observer. The dc bias of the current caused by system delay is also eliminated so that the accuracy of position estimation is improved. The proposed method is verified by experiment, and the results show that the accuracy of the estimated rotor position and dynamic performance of the estimator is greatly improved compared to existing methods.

中文翻译：

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基于高频正负序电流双解调的SPMSM无传感器控制

在表面贴装永磁同步电机（SPMSM）低速无传感器控制中，转子位置估计的高频正弦电压注入方法受SPMSM低饱和突极率和系统延迟的影响，导致估计误差。本文提出了一种利用电机高频正负序定子电流的双解调方法。该方法基于最大化凸起电感分量的影响和最小化噪声显着分量的原则，提高了电流包含角度信息的利用率，提高了位置角度误差馈入的信噪比转子位置观测器。也消除了系统延迟引起的电流直流偏压，提高了位置估计的精度。通过实验验证了所提出的方法，结果表明，与现有方法相比，估计器的转子位置估计精度和动态性能都有很大提高。