PMSM无位置传感器控制的系统延迟补偿方法

提出了一种基于系统延迟补偿的永磁同步电机位置观测方法,以避免在高速下滑模位置观测器精度受永磁同步电机驱动系统中的模拟延迟和数字延迟影响而产生位置估计误差。首先,建立了用于位置估计的典型滑模观测器,并分析了滑模运动的可达性。其次,研究了模拟电路对定子电流的影响,推导了采样电路中的有源滤波、无源滤波及偏置电路的传递函数,计算了采样电路对定子电流造成的总延迟相位。再次,分析了滑模观测器的数字实现过程造成的电流相位延迟。又再次,提出了基于直接信号补偿的方法,补偿了以上因素造成的电流相位误差。所提延迟补偿方法不仅提高了位置估计精度,还改善了闭环控制的电流调节性能。最后,在8 000 r/min电机驱动平台上进行了实验,结果表明所提系统延迟补偿方法提高了位置估计精度。

System delay compensation method for PMSM sensorless control

A position observation strategy considering system delay compensation is presented to avoid the position estimation error caused by analog and digital delay of the permanent magnet synchronous motor drive.First,a typical sliding-mode observer is established and the accessibility of sliding mode motion is analyzed.Second,the influence of analog circuits on the stator current is studied,and the transfer functions of analog circuits are derived.The total delay phase caused by the sampling circuit on the stator current is calculated.Third,the current error from digital implementation of the sliding-mode observer is analyzed.Fourth,a direct signal compensation method used for eliminating the influences of the current error is presented.The proposed strategy lowers the detection error of the sliding-mode observer and the transient process time in closed-loop control.Finally,the proposed strategy is experimentally verified to confirm its merits on system delay effect elimination and system control performance improvement.