Preparation of the ITER Poloidal Field Conductor Insert (PFCI) Test

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 0.6MPa. 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.

Test Results From the PF Conductor Insert Coil and Implications for the ITER PF System

“…The similarity between the CICC of the PFI and the one designed for the PF1 and PF6 is evident, comparing the data reported in Tables I, IV, [20], with the necessary adaptations to the different operating conditions and PF conductor characteristics [15]. Besides the obvious characterization of the DC and AC conductor performance once wound in a coil of relevant length and size, the main test focus was on the following items:…”

“…Further details on the coil design [6], strand and cable manufacturing [7]- [11], coil manufacturing [12], short sample test results [5], [13], and supporting analyses to the insert test [14]- [17] can be found in the extensive list of references quoted. [19], [20], with the necessary adaptations to the different operating conditions and PF conductor characteristics [15]. Besides the obvious characterization of the DC and AC conductor performance once wound in a coil of relevant length and size, the main test focus was on the following items:…”

“…A large part of the PFI test was hence dedicated to the measurement of the cable AC loss vs. cyclic loading. More details on the genesis and finalization of the test program can be found in [15]- [17].…”

“…This coil section is placed in the equatorial plane of the test facility to experience the peak field of the CSMC. The intermediate joint, further away from the midplane of the CSMC, experiences a field which is approximately 25% lower, with both vertical and radial components, as will be the case for the ITER PF coils.The similarity between the CICC of the PFI and the one designed for the PF1 and PF6 is evident, comparing the data reported in Tables I, IV, [20], with the necessary adaptations to the different operating conditions and PF conductor characteristics [15]. Besides the obvious characterization of the DC and AC conductor performance once wound in a coil of relevant length and size, the main test focus was on the following items:…”

The Effect of Inter-bundle Resistive Barriers on Coupling Loss, Current Distribution and DC Performance in ITER Conductors

“…The state of the art, common status of perception is that the application of sub-stage wraps is unfavorable for the DC performance [10], [15]. Here we show that this is not unconditionally valid for all cases and in particular for the Poloidal Field Coil Insert (PFCI) geometry [16].…”