Status of the development of diagnostic pressure gauges for the operation in ITER

Abstract

The ITER Diagnostic Pressure Gauges (DPG) shall provide the measurement of the neutral gas pressure, which is an important parameter for basic control of the operation of the ITER machine as well as for input to physics models of the plasma boundary. The reference sensor is a hot cathode ionization gauge, which is able to operate in an environment with strong magnetic fields (up to 8T), strong and noisy background signals and fast pressure changes. In total 52 DPG sensor heads will be installed in 4 lower ports, 4 divertor cassettes and 2 equatorial ports. The DPG system is currently being developed by IPP in collaboration with F4E and Sgenia within the Framework Partnership Agreement FPA-364. As part of the system level design activities several different architectures of the DPG system, including gauge head and supporting electronic equipment, have been evaluated in detail with the aim to fulfil technical requirements imposed by the integration in ITER. Most important steps made towards the currently defined baseline design of the DPG system, which is based on ASDEX Pressure Gauge (APG) technology, are discussed in the present paper.