Abstract:
To overcome the limitation of the traditional beam stacking method and accumulate the heavy ion beam to higher intensity, Heavy Ion Research Facility in Lanzhou (HIRFL) will adopt Moving Barrier Bucket (BB) stacking scheme in Cooling Storage Experimental Ring (CSRe). The amplitude, phase and periodic adjustable BB voltage produced by the Radio Frequency (RF) control system is the core of this accumulation mode. However, due to the wide-band characteristics of BB voltage and the nonlinearity of RF system, there will be serious distortion of BB voltage in RF cavity. Based on the analysis of the characteristics of BB voltage and RF system, the predistortion feedforward control is introduced to eliminate the distortion. This paper describes the mathematical model, simulation, hardware and software design and test results of this method in detail. The results will be helpful to the BB stacking experiment of HIRFL-CSRe and BB stacking mode of High Intensity heavy-ion Accelerator Facility (HIAF).