The Study and Development of Excitation Source for Sensors of the AMB System in HTGR

Abstract

The High Temperature Gas-Cooled Reactor (HTGR) is developed widespread in the world nowadays. The helium turbine of the 10 MW high temperature gas-cooled test module reactor with the core made of spherical fuel elements is under research at the Institute of Nuclear and New Energy Technology of Tsinghua University in China. Magnetic bearings are widely applied in HTGR, where the rotating machineries are running under highly pure helium environment. Compared with conventional bearings, Active Magnetic Bearings (AMBs) possess several attractive advantages, such as contact-free, no-lubricating and active damping vibration. The sensors are the key components of the AMBs system and are responsible for measuring the position and movement of the rotor, the operating temperature and so on. In order to operate the sensors successfully, a stable and efficient excitation source is needed. The conventional excitation source, which is equivalent to the class AB power amplifier circuit, is inefficient and unstable in the previous experiment, and therefore a new source using class D power amplifier is under research and development. The paper will present the design, simulation and test of the new excitation source for the sensors of the AMBs system.