Measurement of Unbalance Vibration Phase for Active Magnetic Bearing in High Temperature Gas-Cooled Reactor

Abstract In high temperature gas-cooled reactor (HTGR), the primary helium circulator (PHC) is the key component of the reactor. The active magnetic bearing (AMB) has some outstanding advantages such as micro-friction, no need of lubrication, high temperature resistance, extended life and so on. It is the ideal support device for the rotor of the PHC because it can ensure a clean helium environment. Generally, due to the existence of mass imbalance of the rotor, the AMB system will generate unbalance vibrations during operation. Accurate measurement of the unbalance vibration phase is of great significance to the analyses of dynamic balance and speed up and down of the AMB system. In this work, the principle of the unbalance vibrations and the incidental problems are analyzed in great detail. And a simple and practical unbalance vibration phase measurement algorithm is proposed by combining hardware structure with software programing. This algorithm consists of real-time peak detection and phase calculation, which can realize real-time and accurate measurement of the unbalance vibration phase. In addition, the proposed method can reduce the effect of the noises of the AMB system. The experiment results demonstrate that the proposed algorithm effectively revises the conventional phase measurement methods, improves the accuracy and reduces the inherent error of the system.