JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
@inproceedings{lyles:napac2022-tupa59, author = {J.T.M. Lyles and R.E. Bratton and T.W. Hall and M. Sanchez Barrueta}, title = {{RF System Upgrade for Low Energy DTL Cavity at LANSCE}}, & booktitle = {Proc. NAPAC'22}, booktitle = {Proc. 5th Int. Particle Accel. Conf. (NAPAC'22)}, pages = {478--481}, eid = {TUPA59}, language = {english}, keywords = {controls, DTL, LLRF, cavity, MMI}, venue = {Albuquerque, NM, USA}, series = {International Particle Accelerator Conference}, number = {5}, publisher = {JACoW Publishing, Geneva, Switzerland}, month = {10}, year = {2022}, issn = {2673-7000}, isbn = {978-3-95450-232-5}, doi = {10.18429/JACoW-NAPAC2022-TUPA59}, url = {https://jacow.org/napac2022/papers/tupa59.pdf}, abstract = {{The Los Alamos Neutron Science Center (LANSCE) 100-MeV Drift Tube Linac (DTL) uses four accelerating cavities. In May of 2021, a new RF amplifier system was commissioned to drive the first 4-MeV cavity. It had been powered for 30 years with a triode vacuum tube RF amplifier driven by a tetrode, along with four more vacuum tubes for anode high-voltage modulation. The new amplifier system uses one tetrode amplifier driven by a 20-kW solid state amplifier (SSA) to generate 400 kWp at 201.25 MHz. The tetrode amplifier is protected for reflected power from the DTL by a coaxial circulator. The new installation includes cRio controls and a fast protection and monitoring system capable of reacting to faults within 10 µs. A new digital low-level RF (LLRF) system has been installed that integrates I/Q signal processing, PI feedback, and feedforward controls for beam loading compensation. Issues with LLRF stability were initially encountered due to interaction from thermal-related RF phase changes. After these issues were solved, the final outcome has been a reliable new RF system to complete the overall upgrade of the LANSCE DTL RF power plant.}}, }