Speaker
Description
Modern superconducting radio frequency (SRF) cavities possess extremely high Q factors often exceeding ten billion, which allows increased efficiency but presents an operational challenge due to detuning effects such as Lorentz force detuning and microphonics. Uncompensated detuning will dramatically increase radio frequency (RF) power consumption. To be operable, SRF cavities must lower the Q factor i.e. increase the bandwidth by external loading. The quarter wave resonators and half wave resonators in the FRIB linac use stepper tuners and pneumatic tuners respectively. Both tuner types only compensate for slow detuning (less than 1 Hz) and the microphonics effect (tens of Hertz) is handled by RF control with additional power. The FRIB upgrade cavity is a 644 MHz elliptical cavity equipped with a piezo tuner which makes the compensation for microphonics possible. In this study the feasibility of using active disturbance rejection control (ADRC) to handle the nonlinear behavior the piezo tuner introduces is explored. It is also compared to other existing control methods such as proportional, integral and derivative (PID) control and narrowband active noise control (NANC).
Funding Agency
Work supported by the U.S. Department of Energy, Office of Science under Cooperative Agreement DE-SC0023633, the State of Michigan, and Michigan State University.
| I have read and accept the Privacy Policy Statement | Yes |
|---|