Microphonic Noise Cancellation in Super-Conducting Cavity

In particle accelerators it's important to have a stable accelerating system for the beams of particles. The accelerator cavity should be controlled under it's resonance frequency with no disturbance to get the best performance. The particles would be accelerated to the highest desired speed. The Detuning of superconducting radio frequency (SRF) cavities is mainly caused by the Lorentz force, which is the radiation pressure induced by a high radio frequency (RF) field, and environmental mechanical vibrations that induce undesirable interference signals referred to as microphonics. The above factors can be described by a second order differential equation of the mechanical vibration modes of the cavity. In this paper three dominant mechanical vibration modes for the system has been considered and a control scheme has been designed based on input-output linearization. The stability analysis system has been considered by defining a Lyapunov function. It is shown through simulation studies that the proposed control technique can successfully the suppress microphonic noise due to the SRF cavity's dynamics.

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