基于锁相环跟踪算法的高精度轴角-数字变换系统研究

针对传统高精度集成轴角-数字变换系统外围电路复杂、成本高的特点，提出一种基于锁相环跟踪算法的全数字式轴角-数字变换系统方案。利用TMS320F2812的PWM模块产生旋转变压器激磁信号，根据该激磁信号，旋转变压器输出差分正、余弦信号，采用高精度的外围独立采样模块AD7606采样该差分正、余弦信号，依据采样的差分正、余弦信号，基于TMS320F2812设计的锁相环跟踪算法计算电机磁极位置。将该轴角-数字变换系统应用于一台安装有电气误差为±10′的单极对旋转变压器的伺服同步电机，对其进行了实验研究。研究结果表明，该轴角-数字变换系统外围硬件电路简单、成本低，角度测量误差小于10.66′，实现了高精度的轴角-数字变换。

Research on High-Accuracy Resolver-to-Digital Conversion System Based on PLL Tracking Algorithm

This paper proposes an all-digital resolver-to-digital conversion(RDC)system using phase-locked loop (PLL)tracking algorithm to solve the problems of complex peripheral circuit and high cost for conventional high-pre?cision integrated RDC system. Firstly,excitation signal is obtained from PWM module of TMS320F2812. Secondly, the resolver outputs differential sine and cosine signals according to the excitation signal,the differential sine and cosine signals are sampled by a high-precision peripheral AD7606 independent module. Then the rotor angle is esti?mated with the PLL tracking algorithm based on TMS320F2812. The proposed RDC system is applied to a servo syn?chronous motor installing the resolver with one pair of poles,the electrical error of the resolver is ± 10′,and experi?ments are carried out. The research results show that the RDC system has the features with simple hardware struc?ture and low cost,the angle error is less than 10.66′,and high-precision resolver-to-digital conversion is achieved.