Primary attempt for simulation feedback system of low frequency

In order to improve the accumulation of the injected beam, it is very necessary to restrain β oscillation because of injected system error. This thesis systematically introduces the research for injection beam instability, the design principle and circuit of the feedback system for restraining the injected β oscillation of HLS using the turn by turn system［１］. Meanwhile, it also provides the result of preliminary experiments. As the proof of the theory and pre-study, we use a relatively simple analog filter and phase shifter to counteract the kicker course, which causes the β oscillation. From experiment result, it can be seen that the obvious restraining effect using the feedback system. All of these are the foundations of development for feedback system of bunch-by-bunch and lower