Development of experimental control system for regenerative heating process of high-speed cryo-adsorption pump

Abstract

The vacuum system of the Negative-ion-based Neutral Beam Injector (NNBI) verification prototype of the China Fusion Engineering Test Reactor (CFETR) employs a built-in ultra-high-speed cryo-adsorption pump utilizing forced-flow cooling as the main pump, which functions through four major processes: cooling, stable operation, regeneration, and temperature rise. The research analyzes the key technical problems of engineering that must be solved,such as natural regeneration takes a longer time with temperature uncontrollable, lead to low experiment efficiency. An efficient and safe controllable technical method for the regeneration heating process was proposed,and regeneration heating experimental control system, including an equipment layer, control layer, data acquisition and monitoring layer, was designed to control the regeneration heating process of the cryo-adsorption pump. The signals collected by temperature sensors are processed and transmitted through signal isolators to the host computer for display and storage.The target temperature is manually set on the host computer. An improved generalized predictive control (GPC) algorithm and a fuzzy proportional integral derivative (PID) control algorithm are used in the control layer to control the heating process.The designed activation regeneration heating control experimental system was embedded in the comprehensive experimental test bench of cryo-adsorption pump for experimental verification, and the test experiment was carried out.The results show that the system can control the regenerative heating process in an efficient, safe and stable way. This lays the foundation for further development of control functions in the regeneration process of the cryo-adsorption pump equipped in the NNBI verification prototype, and provides a design basis for the vacuum system of fusion engineering experimental reactors.