为了克服横向耦合束团不稳定性对合肥光源的不利影响, 在合肥光源(HLS)研制了一套数字横向逐束团反馈系统。该系统使用直接采样前端, 同时针对合肥光源水平方向工作点和垂直方向工作点太过接近的情况, 修改了数字处理器的FPGA程序, 使得单个处理器能够实现独立的双通道反馈。束流试验验证了反馈系统能有效抑制横向不稳定性, 并可以提高注入流强。

The design and primary experiment of the digital transverse bunch-by-bunch feedback system in Hefei light source are introduced. This transverse feedback system was developed to conquer the transverse coupled-bunch instabilities. It employed direct sampling front-end to simplify the electric circuits and tuning work. Because of the close tunes of horizontal and vertical directions. The FPGA code of the digital feedback processor was reprogramed to fulfill two-independent-feedback in one-processor. Through the beam test, the digital feedback system could suppress the transverse instabilities, and increase the injection beam current.