倍角坐标系下的随机高频信号注入解调策略

Random high frequency signal injection demodulation strategy in double angle coordinate system

针对传统高频信号旋转注入法中引入较多带通与低通滤波器的问题,提出一种新的高频信号注入法信号提取策略,将旋转高频电压信号注入估计旋转坐标系来进行电机激励,并依据数学计算,取消传统方法中低通滤波器的使用,来简化信号提取过程,是永磁同步电机低速无位置控制中一种新的高频注入形式及解调策略。同时,对于定频注入带来的噪声问题,通过将注入信号频率随机化,来抑制电机运行电流频谱中造成的谐波尖峰,从而降低噪声。最后通过仿真及实验,验证了该方法不仅拥有良好的位置估算精度,能有效适应低速下转速及负载变化,提高系统可靠性;同时从电流频谱分析中可知所提方法分散了谐波处的能量峰值,有效降低了噪声,拓展了高频注入的应用领域。

Aiming at the problem of introducing more band-pass and low-pass filters in the traditional rotating injection method,a high-frequency signal injection method signal extraction strategy is proposed.The rotating high-frequency voltage signal was injected into the estimated rotating coordinate system to perform the motor Excitation.Based on mathematical calculations,the use of low-pass filters in the traditional method was eliminated.At the same time,for the noise problem caused by fixed-frequency injection,the frequency of the injected signal was randomized to suppress the harmonic spikes in the motor operating current spectrum,thereby reducing noise.Finally,it is verified through simulation and experiments that the method has good position estimation accuracy,and effectively adapt to speed and load changes at low speeds,and improve system reliability.The current spectrum analysis shows that the proposed method disperses the energy peaks at the harmonics,which reduces noise effectively and expands the application field of high frequency injection.