Research On Tuning Method Of RF Cavity Based On Extremum Seeking Algorithm With Sliding Mode

Frequency tuning system is one of the key structure in RF system to provide accelerating field for particles.There are various methods for tuning of RF cavity which are based on phase difference and reflected signal of RF cavity.The change of environmental temperature make phase measurement be difficult and inaccurate.Besides,it is necessary to adjust empirically with application of phase measurement.The change of environmental temperature can be neglected with application of reflected signal measurement.And,tuning method based on reflected signal of RF cavity is with good accuracy and a faster start-up time.Analyse the equivalent circuit of RF cavity for designing of tuning system of RF cavity based on reflected signal.Provide the theoretical basis for further research of RF cavity tuning method based on reflected signal by solving differential equations to obtain the function of reflected signal when input signal of RF cavity is continuous.The robustness of extremum seeking algorithm with sliding mode is strong,and convergence speed of this algorithm can be adjusted in advance.Improve extremum seeking algorithm with sliding mode by Lyapunov stability analysis for designing of tuning system of RF cavity.Change the controlling gain and reference signal based on Lyapunov stability analysis and feature of tuning process of RF cavity in SSC-LINAC(Separator Sector Cyclotron).Test the algorithm by designing the hardware platform and simulation.The results indicate that the frequency stabilizing system can achieve the goal of SSC-LINAC RF cavity tuning with a faster start-up time automatically.And the system can be in operation for a long time,which prove the feasibility of extremum seeking algorithm with sliding mode in designing of RF cavity tuning.