Electrical and thermal designs and analyses of joints for the ITER PF coils
ABSTRACT The Poloidal Field (PF) coils of the International Thermonuclear Experimental Reactor (ITER) are designed with NbTi cable-in-conduit conductors wound in double pancakes which are connected in series by joints. The electrical analysis of these joints includes estimation of the dc resistance, calculation of ac loss power, of loop currents and local Joule heating during the whole plasma scenario. The effect of a plasma disruption is also considered. The thermal analysis is performed using a transient thermohydraulic two-fluid code, modeling the two-channel structure of the cable as well as the counter-flow heat exchanger created in the joint. We show that the CEA twin-box concept using compressed cables inside independent copper-steel boxes is quite usable in all the ITER PF coils. A discussion about possible options (copper RRR) is also presented.
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ABSTRACT: The Poloidal Field Conductor Insert (PFCI) of the International Thermonuclear Experimental Reactor (ITER) has been designed in the EU and is being manufactured at Tesla Engineering, UK, in the frame of a Task Agreement with the ITER International Team. Completion of the PFCI is expected at the beginning of 2005. Then, the coil shall be shipped to JAERI Naka, Japan, and inserted into the bore of the ITER Central Solenoid Model Coil, where it should be tested in 2005 to 2006. The PFCI consists of a NbTi dual-channel conductor, almost identical to the ITER PF1 and PF6 design, ∼45 m long, with a 50 mm thick square stainless steel jacket, wound in a single-layer solenoid. It should carry up to 50 kA in a field of ∼6 T, and it will be cooled by supercritical He at ∼4.5 K and ∼0.6 MPa. An intermediate joint, representative of the ITER PF joints and located at relatively high field, will be an important new item in the test configuration with respect to the previous ITER Insert Coils. The PFCI will be fully instrumented with inductive and resistive heaters, as well as with voltage taps, Hall probes, pick-up coils, temperature sensors, pressure gauges, strain and displacement sensors. The test program will be aimed at DC and pulsed performance assessment of conductor and intermediate joint, AC loss measurement, stability and quench propagation, thermal-hydraulic characterization. Here we give an overview of the preparatory work toward the test, including a review of the coil manufacturing and of the available instrumentation, a discussion of the most likely test program items, and a presentation of the supporting modeling and characterization work performed so far.IEEE Transactions on Appiled Superconductivity 07/2005; · 1.04 Impact Factor
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ABSTRACT: In this paper, we discuss the predictive analysis performed in support of the test program of the International Thermonuclear Experimental Reactor (ITER) poloidal field conductor insert (PFCI). A subset of the test program items was considered, with particular emphasis on DC performance and AC losses. The results and implications of the comparison of selected predictions from different laboratories will be presented.IEEE Transactions on Appiled Superconductivity 07/2007; · 1.04 Impact Factor