针对目前旋变软件解码中的采样包络面存在非理想偏差问题，从理论推导了幅值偏差、直流偏差会对旋变软件解码的输出角度叠加一个2倍频波动，正交偏差会叠加一个同频波动。提出了基于离散傅里叶变换（DFT）的矫正方法，利用该方法实现了幅值偏差、直流偏差和正交偏差的提取，并对这3种偏差设计了相应的矫正环节。同时又推导了存在转速误差条件下使用DFT方法提取到的幅值偏差、直流偏差存在一个和旋变包络面初始相位相关的波动误差，并通过取一段时间内波动平均值的方法解决了该误差对提取结果的影响。最后通过仿真试验验证了推导的正确性，搭建了拖台架并进行旋变标定试验，对比标定前后数据，表明偏差矫正后的锁相环输出的角度线性度更好，转速波动更小，相应的dq轴电流的指定阶次波动也更小。

Aiming at the problem of non-ideal deviation on sampling envelope surface in current resolver software decoding, the current mainstream error correction methods are analyzed and divided into three categories: input correction, phase locked loop correction and output feedback correction. Then it is deduced theoretically that the amplitude deviation and DC deviation will superimpose a double frequency fluctuation on the output angle decoded by the software, and the orthogonal deviation will superimpose a fundamental frequency fluctuation. An input correction calibration method based on discrete Fourier transform (DFT) is proposed. The amplitude deviation, DC deviation and orthogonal deviation are extracted by this method, and the corresponding correction steps are designed for these three deviations. At the same time, it is deduced that there is a fluctuation error related to the initial phase of the envelope surface in the amplitude deviation and DC deviation extracted by DFT method when the rotational speed error occurs, and the influence of this error on the extraction results is solved by taking the average value of the fluctuation during a period of time. Finally, the correctness of the derivation is verified by simulation, and a resolver calibration experiment is set up for the towing platform. Comparing the data before and after calibration, it is shown that the output angle linearity of the phase locked loop with corrected deviation is better, the rotation speed fluctuation is smaller, and the corresponding dq axis current of the specified order is also smaller.