基于单片机的旋转变压器—数字转换器的研究

【作者】 王晓露；

【导师】 刘诗斌；

【作者基本信息】 西北工业大学 ， 电路与系统， 2006， 硕士

【摘要】 旋转变压器---数字转换器作为现代伺服系统中被广泛使用的角位置测量系统,大量应用于高精度及大中型数控系统、机器人控制、工业控制、武器火力控制及惯性导航领域中。 传统的角测量系统面临的问题有:体积、重量、功耗偏大,调试、误差补偿试验复杂,费用较高。本文从微型化、智能化的方向进行研究,是解决传统角测量系统所面临问题的好途径。 本文所研究的旋转变压器---数字转换器是由信号调理模块、系统芯片C8051F064和输出控制模块组成的。整个系统的三路输入信号为X=Asinθcosωt、Y=Acosθcosωt和Z=U cosωt(基准信号),输出信号为偏转角θ,输出形式为16位数字量。信号调理模块是由模拟电路组成的,包括信号输入电路、相敏整流电路、滤波电路和直流稳压电源电路,其难点在于相敏整流电路的设计。信号调理模块的主要功能是把输入的交流信号X=Asinθcosωt、Y=Acosθcosωt转变成直流信号Bsinθ和Bcosθ,并使输出的直流信号在0～2.4V之间;系统芯片C8051F064是CYGNAL公司近年来推出的一款功能齐全的完全集成的混合信号片上系统型单片机。在本文所设计的系统中,系统芯片的输入信号为直流信号Bsinθ和Bcosθ,通过片内自带的2个16位A/D转换器对输入信号的数据进行采样和转换,并对转换完的数据进行滤波处理,以减小由于外界干扰而产生的误差,再用除法和反正切函数解算出偏转角θ的16位数字量;输出控制模块主要完成的功能是通过UARTO向计算机实时发送由单片机计算出来的偏转角度θ的16位数字量,而串口的RS-232电平与单片机系统采用的是TTL电平之间的转换所采用的转换芯片是MC1488和MC1489。 本文还分析了该系统误差产生的原因和误差形成的过程,并将该过程描述为几何上从圆到椭圆的变化过程。在最佳椭圆拟合的基础上提出了一种误差补偿方法,该方法可以不需要基准设备对系统中存在的各种误差进行自动校正。 实验结果表明,本文所设计的旋转变压器---数字转换器的硬件组成和软件实现基本能够较精确的完成上述的信号转换和数据运算。更多还原

【Abstract】 Revolver-to-Digital Converter is the angle-measured system that is extensively applied in servo systems. It is large quantitatively used in high-accuracy as well as large and medium-sized digital control systems, robot control systems, industrial control systems, weapon control systems and inertial navigation domain.But the larger size and higher power consumption of existing angle-measured systems influences the performance of measured systems, especially used in digital systems. The higher cost of the deviation compensation and error correction is another problem of existing angle-measured systems. This thesis studies micro-intelligent angle-measured systems to solve these problems.This paper introduces a kind of Revolver-to-Digital Converter, which is composed of analog circuit, microprocessor and serial interface. The three-path input signal is X = A sin θ cos ωt , Y = A cos θ cos ωt and Z = U cos ωt . The output signal is deflective angle θ by 16 bit digital quantities. Analog circuit is principally made up of phase rectifier circuit, square-ware generator and filtering circuit. It can transform the input alternating current signal into the direct current signal. Analog-to-digital converter which is in the microcomputer changes input analog signal into digital signal, which is convenient for handle and operate data in microprocessor. In microprocessor, the converted digital signals B sin 9 and B cos 9 convert to the digital signal 9 through the function of division and arc tangent.The reason about the measured error of Revolver-to-Digital Converter is found out, a fast and effective method about compensation is brought forward. It has gained the satisfactory effect in application.At last, the experimental data shows, the hardware and the software of Revolver-to-Digital Converter can relatively accurately complete above-mentioned signal conversion and data operation.更多还原