in order to protect the control system, the control system and measurement system in the high power device should be fully i-solated. The AD650 V/F (voltage-to-frequency converter) provides a combination of high frequency operation and low nonlinearity previously unavailable in monolithic form. The analog signal can be transformed in frequency mode and the signal loss is very low. So it is widely used in the remote signal transmission. The principle, the system composition and hardware design of the whole transmission system are described in this paper. The experiment results show that the system has many advantage, such as low signal loss ( less than 0. 1%) , high transfer data ratei far transmission distance, high linearity and resolution. Meanwhile, it can be not influenced by the electromagnetic field interference in the transmission proceeding. The circuit is simple and the performance is reliable.%在高电压、强磁场的强功率工况下,为了保护控制系统,须将测量系统和控制系统进行高低电位的隔离；采用电压频率(V/F)转换器AD650以频率形式通过数字光纤传输模拟信号,是高低电位隔离、远距离传输模拟信号而又不损失精度的最好解决方法;文中论述了其工作原理、系统组成,详细分析了硬件设计,并进行计算,确定其参数；实验结果表明,基于AD650芯片的传输系统,采用光纤传输,模拟信号传输精度小于0.1％,数据传输速率高,传输距离远,而且传输过程不受外界电磁场干扰,具有良好的线性度和分辨率；电路结构简单,对外界电容要求也简单,仅要求保持良好的稳定性,在实际工程应用中得到了优良的结果.
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