闭环轴角解算误差分析及精度补偿方法

高精度的光机运动控制对空间光学遥感器的成像品质具有重要意义。旋转变压器是光机运动控制系统的重要角度测量元件之一，提高旋转变压器轴角解算精度对提高光机控制性能有重要作用。文章首先分析了闭环鉴幅式轴角解算原理，其次推导了由于旋变测量信号不完全理想带来的解算误差模型，其误差呈正弦分布，频率为被测信号频率的2倍，幅值与误差系数成正比。并用实验数据证明了误差模型的正确性。最后给出了基于模拟信号的硬件补偿方法和基于数字信号的软件补偿方法。实验证明了补偿措施有效，能将解算误差降低一个数量级。

Analysis and Compensation of Position Error Based on Loop Tracking Resolver-to-digital Converter

Optic-mechanical control with high precision is an important task for high quality of image in the field of space optical remote sensor. Resolver is one of the most important angular position measuring components in optic-mechanical motion control system. The precision of resolver-to-digital converter directly influences optic-mechanical control performance. This paper analyses the principle of tracking loop re-solver-to-digital converter firstly. Furthermore a position accuracy model involving nonideal resolver signal characteristics is deduced. The model has a distribution of sine wave and has a frequency twice of the resolver signals. The amplitude of the sine wave is proportional to the error coefficient. Finally, the methods for mini-mizing nonideal resolver signal are discussed using software and hardware. The experimental results agree with the theoretical analysis well, and prove that methods of compensation measure are effective and the precision is improved by one order of magnitude.