脉冲调制器稳定性监控中的数据采集与处理

Data acquisition and processing in stability control system of LINAC modulator

设计采用反馈控制的方法改善脉冲调制器输出高压脉冲幅度稳定性,分析了实现稳定性目标对数据采集系统软、硬件的要求,介绍了相关的实验测试和信号处理方法。数据采集系统由Stratix ii FPGA开发板、AD6645、上位PC机组成,借用差分放大器提高测量分辨率。数据处理采用脉冲采样样本均值作为表征幅度的特征量,并采用平均、插值、数字滤波、BP神经网络等方法来提高幅度监测值的分辨率能力和抗干扰能力。

In this paper, we report the design of data acquisition （DAQ） and processing （DSP） system for feedback control of a linac modulator to improve amplitude stability of its output HV pulse. Hardware and software requirements for the system are analyzed to achieve the required stability, and relevant experimental results are given. The DAQ system consists of stratix ii FPGA board, AD6645 and upper PC. The measurement resolution is improved by use of differential amplifier. DSP algorithm takes sample mean value as pulse amplitude. Methods of average, interpolation, digital filtering, BP Neural Network etc. are practiced to improve monitor resolution and anti-jamming capacity.