Commissioning of ITER heat rejection system for low load

Abstract: This project has commissioned the control logic of the Heat Rejection System (HRS) at ITER, the international fusion project. The HRS is a large system, including 10 cooling towers, 13 pumps, and pipes large enough for a water flow of several thousand kg/s. All of this will becontrolled with automatic control logic. The thesis project took place during the commissioningof the HRS for early operation of the ITER fusion reactor. The design documentation of the HRS was complemented with a set of Instrumentation and Control (I&C) documentation that provide information on the control logic and the signals processed by the Programmable Logic Controller. The control logic was presented in Control Logic Diagrams (CLD), which were tested and verified on the ITER site with dry component tests and functional tests with fluid in thesystem. New control logic was implemented for the low heat load scenarios of the ITER plasma operation. The commissioning team at ITER, and later the operations team, will continue testing and updating the HRS control logic with the CLD as input document. The group that worked on the project involved commissioning engineers, I&C engineers, and operators. A conclusion of this project is that for the CLD to be useful they will have to be continuously updated, and thisprocess should, just as the process of creating them, include engineers of all the concerned disciplines of the HRS.