Terminal voltage stabilization of pelletron tandem accelerator

Abstract

An NEC terminal voltage stabiliser TPS-6.0, based on conventional corona control, has been installed and investigated on the ANU 14UD tandem accelerator. The fluctuations in the charge transport of the electrostatic pelletron generator and their correlation with mechanical oscillations of the chains and terminal voltage ripple have been analysed. Emphasis during commissioning is placed on the components of the two-loop feedback system and on the application of this system to production of high energy-resolution beams. The relationship between transfer functions for the two loops required for optimum operation is discussed. This system produces the beam position at the image slit of the 90 energy-analysing magnet with long-term stability equivalent to a 3.9 kV FWHM fluctuation of the terminal voltage. The concept of novel fast control loop utilizing the high-frequency component from the image slits to control the voltage of the last gap of high-energy acceleration tube is described. Show more